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Recent design and utilization trends of small satellites in developing countries
Acta Astronautica 71 (2012) 119–128
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Recent design and utilization trends of small satellites in developing countries$ Mohamed B. Argoun Cairo University, Department Aerospace Engineering, Egyptian Space Program, Egyptsat-1, Giza, Egypt
a r t i c l e i n f o
abstract
Article history: Received 24 April 2011 Received in revised form 24 July 2011 Accepted 30 July 2011 Available online 23 September 2011
Several small remote sensing satellites have been developed and launched during the last decade by several developing countries in Africa, the Middle East and East Asia. These satellites share among them several features; chief among them is that they were developed for use in developmental planning and to gain access to space technology. The first generation of those satellites had a relatively course resolution of about 30 m, but the second generation reaches a resolution of 2.5 m. This group of satellites also have ‘‘similar’’ designs, which stems from the fact that they were developed to achieve a similar purpose: introducing developing countries to space technology and application through small remote sensing satellites. The other side of building national space programs in developing nations is building the technological base for satellite manufacturing, building the infrastructure for operation and utilization of these satellites and most importantly building the user community and the user applications, which uses these results for sustainable development. This paper attempts to assess the degree to which these objectives were achieved for various satellites. In addition to these more ‘‘programmatic’’ aspects, the paper attempts to shed light, from published information, on some aspects of the recent trends in designs of small remote sensing satellites. & 2011 Published by Elsevier Ltd.
Keywords: Satellite Space technology Space programs Developing countries
1. Introduction Small satellites, mainly for remote sensing have emerged during the last two decades as an effective tool for enabling developing countries to enter the space field and benefit from space technology [1]. The concept of building indigenous small satellites in developing countries as a means of transferring space technology to these countries and expanding the base of satellite product use has emerged in the 1990’s. Several satellite manufacturing companies started offering this technology in the form of satellite technology transfer packages including training and know-how to developing countries. Several developing countries adopted this concept of transfer of space technology through building of small
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This paper was presented during the 61st IAC in Prague. E-mail address: [email protected]
0094-5765/$ - see front matter & 2011 Published by Elsevier Ltd. doi:10.1016/j.actaastro.2011.07.024
satellites and acquiring the technology and training in the process. A number of studies have appeared, which report and examine the emergence and evolution of space programs in developing countries on a regional basis. For example, Romero [2] examines and discusses the space programs in five Latin American developing countries. However, as the development of these space programs progressed, it became clear that the sustainability of the process depends more on the stimulation of demand of space products than on the technical specifications and the initial success of building the first satellite. The first satellites were usually built by the satellite manufacturing company, which is transferring the technology. The second satellite and the following space products (smaller satellites, satellite components, etc.) are the ones typically built by the developing country. To gage the success of a developing country space program we have to examine the extent to which its satellites and components are built by local and indigenous entities.
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We argue here that the building of the second generation satellites will not be attractive unless there is significant utilization of the first satellite products. Therefore, there is a need to concentrate on spreading the use of remote sensing satellite products, expand the satellite imagery user community and create new value added products in order to show the economic benefits and sustain the momentum for developing countries to enter into the space field. Moreover, the government interest in building the second generation satellites frequently wanes and sometimes stops after the immediate return from launching the first satellite is obtained. In this case the scientific space community must resort to other means to maintain the momentum of acquiring and building the space technology base in the developing country. Such means include building smaller satellites (Cubesats) [3], building satellites in universities, building subsystems rather than complete satellites and finally encouraging research oriented at design of satellite components and payloads. In this paper we examine the routes taken by five developing countries in Africa and Middle East in achieving the transition from building their first satellites through international space companies under a technology transfer and training programs to producing the second generation satellites indigenously. The countries considered are Algeria, Egypt, Nigeria, South Africa and Turkey. We examine some of the paths followed for enhancing the technical capability of these countries to build small satellites and discuss the factors and measures needed to maintain the initial momentum, which accompanied the entry of several developing nations into the space field. The second section of the paper considers the common objectives of space programs in developing countries. In the third section we briefly examine some technology transfer aspects in the space programs under consideration. This is also extended into the fourth section. In the fourth section we present the first generation satellites in more detail. The fifth section deals with the second generation satellites and discusses the paths taken by different countries to implement this phase of their space programs. We also discuss various design changes and take a look at the technical changes and programmatic ways of entering into this second phase. In Section 6, we present an important initiative for cooperation in building
a joint small remote sensing satellite (AFRICASAT) based on the experience and know how those developing countries gained in the first phase of developing their national space programs. The last section deals with the utilization of satellite products, which we stress is an essential element in ensuring the sustainability of space programs in developing countries.
2. Common features and objectives of space programs in developing countries When space programs started in the developing countries in Africa and the middle east they had the following common objectives. 2.1. Build and launch first national satellite. 2.2. Acquire knowledge and know-how by building indigenous satellites. 2.3. Transfer knowledge and know-how to local industry. 2.4. Engage national universities and research centers in space research and technology. 2.5. Increase the utilization of space applications and products. 2.6. Establish a National Space Agency. Table 1 shows general features of space programs in the five developing nations considered in this study. The agencies within which these programs were developed are: i) Algerian Space Agency. ii) National Space Research and Development Agency—Nigeria. iii) National Authority for Remote Sensing and Space Sciences, NARSS, Egypt. iv) Stellenbosch Univ., South Africa. v) Space Technologies Research Institute, Turkey. Approximately a decade has passed since the various countries launched their respective space programs. These space programs have evolved generally along similar paths with some variations due to varying conditions in each country. In the following we discuss briefly the status and achievement of each of the space programs under study.
Table 1 General features of Space Programs in five developing nations. Item
Algeria
Nigeria
Egypt
South Africa
Turkey [4]
Year space program started First satellite name Launch date Ground resolution Company/agency/ country cooperated with Agency supervising Status of second generation satellite
2002
1999
1999
1991
2001
Alsat-1 November 2002 32 m Surrey, UK
NigeriaSat-1 September 2003 32 m Surrey, UK
Egyptsat-1 17/4/2007 7.8 m Yuzhnoye/Ukraine
SunSat February 1999 15 m Indigenous
BilSat 2003 27.6 m SSTL,UL
ASA (i) Alsat-2A Launched July 2010
NASRDA (ii) Nigeriasat-2 planned for launch in 2011
NARSS (iii) Not yet started
SU (iv) SumbandilaSatlaunched 17 September 2009
UZAY (v) Manufactured and shipped for launch 7/2011
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3. Technology transfer within the space programs The first satellites were generally very successful. Their success however was more a testament to the capabilities of the companies that manufactured them than a testament to the strength of the space programs in the developing nations. That last aspect can be measured by the number of engineers and specialists who were trained, the level they achieved in technology transfer and the share they contributed in the next generation satellites. In the case of Egyptsat-1 the number of engineers and specialists trained was 64 covering virtually all areas of design, manufacturing and testing of small satellites. The experience transferred to them is recorded in a large number of documents written for that purpose. The structural and engineering models of the satellite were transferred to Egypt and are used for training. Test equipment used for testing the satellite components and subsystems was transferred to Egypt and erected in an Engineering Model Lab where a functioning model of the satellite is operating and used for training and troubleshooting. A team of satellite operators comprising about 30 engineers was trained for operating the satellite both on the control and the receiving ends and are currently operating the satellite independently. Each of the regional developing countries, which started a space program in the late nineties of the last century, has launched a functional first satellite. In Table 2 we provide a brief list of the salient technical features of the first remote sensing satellites in the five nations considered. The technology transfer aspect of the remaining space programs is discussed in the following section.
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The satellite included a GPS receiver, laser reflectors, magnetometers, star camera, Amateur Radio communications and a 15 m resolution, 3456 pixel, 3-band push broom imager. The satellite structure adopted a modular tray structure where each tray included some elements of the various subsystems (Fig. 2). The optical system has a diameter of 10 cm and a focal length of 570 mm. The pixel size of 10.7 mm translates into 15.01 m from 800 km. The swath width is 3456 pixels 15.01 m ¼51.9 km. An 8 bit image data handling system is used including a 64 Mbyte RAM disk for onboard image storing. The attitude control system employed reaction wheels during imaging and magnetorquers for course attitude control. An extendable tip mass is used for attitude stabilization. Several images were successfully taken and transmitted to the ground from SUNSAT satellite. Some of these results as well as more details on the technical aspects of the satellite are reported in [6]. SunSat failed in orbit a short period after launch in 1999 but South Africa benefited from the developed technology, which reflected in the first indigenous second generation satellite in Africa: Sumbandilasat [7]. 4.2. AlSat-1 The first phase of the Algerian Space Program depended on training and know-how transfer to a core group of Algerian engineers who participated in design and building of AlSat-1. The satellite Al-Sat-1 is the first generation Algerian satellite and is designed and built by
4. Overview of first generation satellites in the region 4.1. SUNSAT—the first satellite in Africa In the early days of the development of small satellite technology transfer activity South Africa developed and launched the first satellite in all developing countries namely SunSat satellite, developed by Stallenbush University. SUNSAT was launched on a NASA sponsored Delta II launch on February 23, 1999 (Fig. 1).
Fig. 1. SUNSAT in-orbit configuration.
Table 2 Developing countries’ first satellites. Country
Algeria
Nigeria
Egypt
South Africa
Turkey
Satellite Name Weight (kg) Orbit-sun synchronous Multispectral/Panchromatic Ground resolution (RBG) (m) Swath width Near Infra Red (NIR) Operational Status
Algeria Sat-1 100 680 km 32
NigeriaSat-1 100 686 km 32
Egyptsat-1 165 668 km 7.8
SUNSAT 64 – 15
BilSAT 129 686 km 26.7/12.6
10 m multi-spectral, 2.5 m panchromatic
52 km – Problems in orbit reported July 1999 6.5 m
– 26.7 m –
Specifications of next generation satellite payload
45 km 39 m Lifetime expired after 39 months in orbit 2.5 m multispectral
640 km 600 km – – Operational as of 2009 Lifetime expired 5 m multi-spectral, 2.5 m panchromatic
–
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Fig. 3. Alsat-1 structure.
country’s national Earth observation needs. The technical features of NigeriaSat-1 are similar to those of AlSat-1 and BiLSat-1. The NigeriaSat-1 satellite was launched on the 27th of September, 2003 [18]. 4.4. Turkey’s space program first phase Fig. 2. SUNSAT Tray structure.
SSTL Ltd. The satellite carries a 32 m ground resolution with a swath width of 600 km. The satellite has dimensions of 60 60 60 cm3 and weighs 98 kg. The satellite attitude control system has 2 ADCS modules each comprises one magnetometer, two sun-sensors and three coiled magnetorquers. The satellite has two booms, which help in stability. The satellite is equipped with a propulsion system with 50 mN thrust and two tanks with a 2.5 litre capacity for each. The optical payload is supported by a total storage capacity of two 0.5 Gbytes of data, which could be downloaded at 8 Mbps (Fig. 3). 4.3. NigeriaSat-1 The first phase of the Nigerian Space Program included building of the NigeriaSAT-1 satellite by SSTL Ltd., and training of 15 Nigerian engineers in a Know-How Technology Training (KHTT), which extended over a fifteen month period of training in the design and building of all subsystems of the NigeriaSat-1 spacecraft. The NigeriaSat-1 spacecraft is similar to AlSat-1 and BiLSAT, which were built for Algeria and Turkey by the same company. The satellite, as the other two satellites, is part of the Disaster Monitoring Constellation, DMC, a collaborative effort for monitoring of natural and man made disasters all over the globe as well as satisfying the
The Turkish space technology transfer team comprised a core of 8 engineers in different disciplines alongside four M.Sc. students and a number of academic staff and technicians at TUBITAK UZAY, TUBITAK Space Technologies Research Institute. The core team gained their experience through working on the development of the engineering model and testing of the BILSAT flight model. Turkish involvement in BILSAT development included two payloads designed and built by Turkish team. The first, named COBAN, is a nine-band low resolution multispectral imager. The second, named GEZGIN, is a DSP based image processing module, which is used to compress images taken by BILSAT-1’s on board cameras [5]. The BILSAT satellite itself on which the Turkish team received their first phase training and know-how is a 130 kg satellite built by SSTL Ltd. and carries a 32-meter resolution imager in 3 spectral bands, in addition to the experimental payloads COBAN, GEZIN built by the Turkish team. The satellite was launched on 27th September, 2003 (Fig. 4). 4.5. First Egyptian satellite: Egyptsat-1 EgyptSat-1 is the first Egyptian remote sensing satellite. It is designed and built by the Ukrainian firm Yuzhnoye SDO. The satellite was successfully launched on 17th April, 2007. The satellite was part of a program to transfer satellite technology to Egypt through partnership with an advanced space faring nation. There was a strong element of training
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Fig. 4. Bilsat 1 [SSTL].
and learning by participation from the Egyptian side. Sixty four Egyptian engineers and specialists received their experience this way through participation in all phases of the satellite design, building, testing, launch and operation. Here are some of the salient technical features of the satellite. The Egyptsat-1 satellite is a three axes controlled satellite with resolution of 7.8 m on the main multispectral scanner. The satellite payload consists of two cameras and a store and forward communication payload. Egypt-Sat-1 main architecture was the star topology architecture based on a central command data handling subsystem, which organizes the data handling between all satellite subsystems, and between satellite and ground (Figs. 5 and 6). The EgyptSat-1 satellite comprises the following Subsystems and components:
Fig. 5. EgyptSat-1 subsytems.
Satellite structure Power subsystem (PSS) Platform command and data handling subsystem (PCDHS)
Attitude determination and control subsystem (ADCS) processing unit four reaction wheels (RW) J star sensor (SS) J magnetometer (MM) J 3 magnetorquers (MT) J angular velocity meter (Gyro) Communcation subsystem (CSS) J S-Band J X-Band Global positioning system (GPS) Telemetry module (TM) Seperation transducers J J
Fig. 6. General view of EgyptSat-1.
Payload J J J
Payload Command and Data Handling Subsystem (PLCDHS) Multi-band Earth Imager (MBEI) Middle-IR Earth Imager (MIER)
Table 3 above summarizes the salient technical features of Egyptsat-1.
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Table 3 EgyptSat-1 main characteristcs and features. Feature
Value
Feature
Satellite total mass (kg) Payload subsystem mass (kg) Scanner type Resolution: multispectral scanner Swath width Orbit type Altitude (km) Inclination (deg) Ascending node local time Attitude control Subsystem Type Accuracy at imaging Angular rate of stabilization at imaging (deg/s) Tilting- pitch and roll Attitude determination
165
Lifetime full performance 3 years reduced performance 2 years Middle Infra-Red Earth Imager (MIREI) Resolution- NIR Scanner 39 m Swath width – Power subsystem Maximum 270 Daily average 53 Solar cells deploayable Communication system S-band control frequency 2089 Mhz S-band telemetry 2268.6 Mhz X-band downlink 8192 Mhz Launch vehicle Dneper-1
49 Push Broom 7.8 m 46 km Sun synchronous 668 km 98 22:30 Active – 3 axes 0.21 0.005 7 351 Star sensor based
5. Second phase of space programs in developing countries All of the five developing countries studied in this paper have successfully launched and operated their first satellites and have entered the second phase of their respective space programs. Those first satellites were built within satellite technology transfer programs conducted by partners from advanced space faring countries with the exception of South Africa, which had a first generation indigenously built satellite, SunSat. In the following we discuss the various approaches taken by these countries to build their second generation satellites. Six directions in satellite and subsystems design and development can be identified among developing nations in the region after the launch of their first satellite. A seventh track is proposed through regional cooperation between the developing countries with the support of an international element represented by the UN office for outer space. The current approaches for building second generation satellites in developing countries are as follows: 5.1 Building larger and more powerful satellites in close cooperation with more advanced space faring countries. 5.2 Development of indigenous satellites based on the experience gained in first satellites. 5.3 Building similar versions of the first satellite to preserve the technology base, replace the existing or expired satellites or as training and technology transfer models. 5.4 Building scaled down versions of the first satellite (e.g. University satellites). 5.5 Building smaller types of satellites as a building stone of experience and acquisition of know-how (CubeSats and Nano Satellites). 5.6 Building subsystems and components. In addition to building satellites some developing countries have taken the path of building satellite
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components and subsystems either to enhance the technological and industrial base or simply because it is a lower funding sub-track. Finally the approach of building a joint African satellite among developing space faring countries in Africa is proposed as a feasible and useful option for sustaining and supporting the space programs in developing countries. In the following we discuss the different approaches taken by developing countries in the Africa and Middle East region in the design and development of second generation satellites. 5.1. Larger and more powerful satellites: Nigeria and Algeria were among the developing nations in Africa, which followed the direction of building larger and more powerful satellites. These two countries adopted the approach of building the second satellite in close cooperation with partners from well developed space faring nations. Nigeria chose to build NigeriaSat-2 with SSTL of UK. The satellite is planned to be launched in the first quarter of 2011. NigeriaSat-2 is a powerful remote sensing satellite, which weighs 285 kg with ground resolution of 2.5 m panchromatic and 5 m multispectral [5]. The satellite is equipped with a 32 m imaging mode to be compatible with the Disaster Monitoring Constellation (DMC), an initiative, which has five countries and five satellites participating for joint monitoring of disaster areas. The spacecraft is based on the SSTL advanced SSTL-300i satellite platform. The second generation high resolution Algerian satellite was launched on July 12, 2010. The satellite named AlSat-2A is designed and built by EDAS/Astrium Corporation and is based on its AstroSat-100 platform. The satellite has a ground resolution of 2.5 m. 5.2. Development of indigenous satellites 5.2.1. South Africa The second track in satellite technology development in African and Middle Eastern countries is to build the country’s
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indigenous follow up satellite based on the country’s own experience and capabilities. This approach is taken by South Africa, which has a much stronger industrial base than the other four countries that have satellite technology transfer programs in the form of the SumbandilaSat [7].
5.2.2. Turkey The other indigenous satellite being built in the region is the Turkish satellite RASAT [4,5], an experimental satellite, which is built within the scope of the second phase of the Turkish Space Program. The satellite is part of a development project for a LEO satellite with 7 m ground resolution. ‘‘RASAT’’ was designed and manufactured in Turkey by the space division of the Scientific and Technological Research Council of Turkey (TUBITAK).
5.2.3. Algeria Algeria is planning to build Alsat-2B satellite in collaboration with Astrium using its 30 engineers and specialists who received training during the process of building AlSat2A. The agreement signed in 2006 by CNTS (Algerian National Space Technology Center) with EADS/Astrium calls for 2 satellites. The second of those satellites Algeriasat-2B will be integrated in Algeria within the small satellite development center (UPDS) in Oran, Algiers [5].
5.2.4. Egypt In the case of Egypt the original strategy of the space program called for building EgyptSat-2, which is a developed version of Egyptsat-1 with enhanced resolution and increased component of local design and manufacturing. Egyptsat-2 was planned to have 60% local component of design and manufacturing. The most technically feasible satellite design is a modified and more evolved version of Egyptsat-1 with a resolution of about 5.4 m. This is the resolution thought to preserve, absorb and deepen most of the technology used in Egyptsat-1. In this satellite the payload will be different from that of Egyptsat-1 but most of the satellite subsystems will be an extended version of Egyptsat-1 subsystems. In this future satellite the Store and Forward payload is expected to be removed. The satellite is likely to be built by NARSS with limited foreign cooperation. Currently, work has not started in Egyptsat-2 beyond the initial phases of mission analysis and preliminary design and it is doubtful that the satellite will be launched in the next year i.e. 2012 as was originally planned. Other ideas of a satellite with 2.5 m resolution are being discussed, but in this case the indigenous content will be very limited. In the absence or delay of a decision to build a second generation satellite in a developing country the technology base of a space industry might erode. To avoid such erosion and to preserve the momentum and know-how several alternative approaches are available to a developing country. The alternatives are in the form of similar satellites, university satellites, Cubesats and building of satellite subsystems. These alternatives are proposed for the Egyptian space program and some are actually implemented.
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5.3. Building similar versions of the first satellite to preserve the technology and replace expired satellites This approach applies in the cases of Egypt and Nigeria. Egypt has recently lost contact with its first generation satellite EgyptSat-1 and needs a replacement satellite. A replacement satellite can be built indigenously in Egypt within the current technical and infrastructure capability of the country. No major changes in this case are expected to be introduced to the design of Egyptsat-1 except for the removal of the Middle Infra Red scanner and the Store and Forward payload and associated changes. The rationale for this alternative is that the cycle of technology transfer is not complete without building an indigenous satellite based on the heritage and technology of the first satellite EgyptSat-1. Building a similar satellite preserves the heritage of EgyptSat-1, builds on it and enhances the process of technology transfer. The heritage of Egyptsat-1, which supports this approach, is presented in the following: a) A proven satellite design, which shortens the cycle of development. b) Proven satellite building and testing technology and methods acquired through the first experience. c) Documentation of all design drawings, calculations, software, testing methods and results, which are provided with the original Egyptsat-1 satellite. d) Test equipment of all satellite subsystems. e) Engineering model laboratory, which includes a full functioning version of the satellite Egyptsat-1 together with test equipment and connections for operation and troubleshooting of all subsystems. f) A large pool of trained engineers in satellite design, testing and operation. Building a similar satellite to EgyptSat-1 has the following advantages: a) It falls within the capability of the trained team and can be built completely indigenously, possibly with some minor assistance from abroad. b) It deepens and enhances the technology base by full utilization and absorption of the transferred technology. c) Some designs can be used as are in the original satellite thus reducing cost, time and effort. d) Low cost, being built and tested in the country. e) It provides a replacement to the first operational satellite EgyptSat-1. In the case of Nigeria the rationale for building a similar satellite is different. It is built alongside NigeriaSat-2. Built as a technology transfer and training model, this mode of enhancing the technology transfer process depends on building a similar model to the satellite built by the technology transferring company for hands on training. The training model is named NigeriaSat-X and is developed with the participation of twelve Nigerian engineers and scientists at the premises of SSTL [9,10].
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The satellite, which will be launched alongside NigeriaSat-2, has a 22 m resolution and is compatible with the specifications of the DMC satellites. 5.4. Build a scaled down version of first satellites (university satellites) Both SunSat [6] and Sumbandilasat [7,8] satellites of South Africa are university built satellites. Schoonwinkel and Milne [8] give some useful experiences on building satellites in a university environment. Building a scaled down version of the first satellite to preserve and enhance the transferred technology is the basis of Egypt’s UNIVERSAT, which is discussed in the following section. This satellite is proposed to be built cooperatively by several Egyptian Universities with Cairo University taking the lead. The objectives of the satellite project are several folds: 1. Preserve the design and technological heritage of Egyptsat-1. It is well known that technology transfer is not complete without the hands-on practical experience obtained through building and testing of a complete indigenous satellite. 2. Expand the technological base of space industry by transferring the technology to the universities, which are the largest pool of scientific personnel in a country like Egypt. 3. Gaining any detailed hands-on experience of building satellite subsystems and assemblies, which was not fully obtained during the first phase of the space program i.e. the phase of technology transfer by direct contact with the transferring agent. The UNIVERSAT satellite is planned to carry a single payload consisting of a 10 m ground resolution optical scanner. The satellite weight is required to be in the 80 kg range (EgyptSat-1 is 165 kg). UNIVERSAT is hoped to provide an indigenously built basic platform for future Egyptian satellites and missions. The funding for the project is sought from Cairo University, NARSS and STDF (Science and Technology Development Fund in Egypt). 5.5. Build CubeSats and other smaller satellites Cubesats are a useful educational and technology transfer tool for satellite technology. This type of small satellites is gaining wide acceptance in universities and in space programs of developed and developing nations alike. In Egypt there is a project for building Cubesats with joint funding from STDF of Egypt and the European Union [17]. 5.6. Build critical satellite subsystems In order to have a serious indigenous satellite building capability a developing country or an agency in that country must be able to build and test satellite subsystems successfully. Among the usual satellite subsystems two subsystems present engineering and technological challenges, namely the payload and the ADCS. As a step toward building indigenous satellites, whether it is a replacement satellite
to Egyptsat-1 or UNIVERSAT there is a joint project between NARSS and Cairo University to design, build and test the two critical subsystems: the payload and ADCS. Once this project proceeds toward implementation other subsystems will be built and tested in a second phase of the project. The third phase will be assembly and integration of the engineering model. In Turkey a similar approach is taken where an R&D sub-program is established alongside the main BiLSAT program to propose, design and build two of the BilSAT research and development payloads: a nine channel medium resolution imager named COBAN and a high performance digital signal processing card named GEZIN, both of which were manufactured in Turkey [4].
6. International and regional cooperation International space projects is an effective way of sharing the technology and lowering cost. In case of developing nations we also add the motivation of sustaining the momentum of budding space programs. As mentioned in [2], Rao [11] has suggested that developing countries should establish ‘‘their own regional and multilateral programs’’ for promoting space technology. In [12] a small satellite project was proposed to be developed by Eastern and South-Eastern European countries. The objectives, designs and main features of a regional satellite project suitable for developing countries of a certain region depends on certain features and factors specific to that particular region. Among these features and factors is the number of countries participating, average or overall level of industry in those countries and the degree of political maturity, which allows regional cooperation rather than unnecessary competition in certain fields. Also, former or existing cooperation programs play a role in promoting wider scope projects. In case of satellite projects the common features of first generation satellites is an asset. For the region of Africa there are common features in the development of their space programs that motivate proposing a joint satellite project. The motivation and objectives for the proposed initiative are as follows: 1. To guarantee the continuation and momentum of developing space industry in African nations by adding an international element to their space programs. 2. To provide a basic platform for various African countries satellite missions. 3. To provide a pool of data for use of space technology in development of Africa. 4. To enhance the process of technology building by providing a feasible technical challenge of building and testing a subsystem and integrating the overall satellite. 5. A step toward regional and international collaboration, which helps establish the norms of such cooperation in the future between developing countries. 6. To provide a low cost alternative for continuation of the space programs for countries, which lack the funding.
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7. To gain experience and fine tune current capabilities in scientific international projects management. 7. AfricaSat: a joint satellite proposal among all space faring developing countries in Africa AfricaSat is a proposed initiative, which was first presented at the 61st International Astronautical Congress IAC in Prague, 27 September–1 October, 2010 [16] to enhance effective satellite technology transfer to African Nations and support space programs currently ongoing at those countries. The countries expected to benefit and participate in this initiative are South Africa, Nigeria, Algeria and Egypt. A representation by the United Nations Office of Outer Space is thought to provide coherence and adds to the success of the initiative. This proposed satellite development is thought to enhance the existing African Resource Management Constellation ARMC initiative already in progress. The AfricaSat platform once developed could be the base for future satellites within the ARMC. 7.1. Technical features of the proposed satellite Technical features of the satellite are selected to suit the current level of know-how and technology acquired by the intended developing countries. 1. The proposed satellite is a small (80 Kg) satellite, which carries a 10 m resolution multispectral imager. This is an intermediate resolution between the high resolution of 2.5 m and 6.5 m carried by the second generation advanced satellites and the 32 m resolution of some of the first generation satellites. 2. The technical features of the various subsystems should reflect the evolved features and designs of the four satellites leading to this joint satellite, namely: Sumbandilasat, NigeriaSat-2, AlgeriaSat-2 and Egyptsat-1. The process and steps of realizing this project are envisaged as follows: 1. The initiative will be presented and discussed in various small satellite conferences and meetings where fine tuning and consensus will be reached. 2. The overall satellite design will be made by a system engineering and overall design group formed from representatives of all nations. 3. Each country will build a subsystem of the satellite in its own territory. Project management: 1. A management and system engineering group will be formed with representatives from all countries. 2. Management meetings will be held in different countries successively once every four months. The progress reports will be presented and the necessary decisions will be made. 3. A review and quality control process will be instated.
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Funding: Each country will fund its own activity and will build the necessary capacity to conduct this activity. The role of UNOOSA: The success of such an initiative requires the role of the United Nations Office of Outer Space Affairs as a binding and monitoring agent. The United Nations Office of Outer Space Affairs UNOOSA is implementing the United Nations Program on Space Applications. Under that program a new initiative dedicated to support capacity building in basic space technology development was recently launched. The initiative is called Basic Space Technology Initiative BSTI [19]1. 8. Utilization of indigenous small satellites in developing countries As mentioned earlier, the utilization of satellite images in national development plans in any developing country is the strongest factor in supporting the cause of sustainable space programs’ development. For this reason the space authorities in developing countries must direct a portion of its efforts to spread the use of space products and introduction of new value added means of creating the market for space technology and hardware products. The level of utilization of space products, namely images and data is generally low in all of the developing nations. There is no available metric for measuring the level of utilization of images. One suggested measure is the number and topics of publication in the various conferences and publication journals in the field, and specifically the regional conferences. In Egypt a joint US-Egypt workshop was held under the title ‘‘Joint US-Egypt workshop for Space Technology and Geoinformation for Sustainable Development’’ Cairo, June 14–17, 2010 to present and encourage the results of using Egyptsat-1 and similar satellites for development. More than forty papers were presented mostly displaying results of using Egyptsat-1 images in various applications such as crop measurement, water resource management and archeology among others. We list 2 papers [13,14] presented in this workshop as examples of work that started to build up using Egyptsat-1 images. Many other examples are found in that workshop and on the website. Along the same line some 24 proposals for projects utilizing the space products of Egyptsat-1 and similar satellites were suggested during the workshop. The funding of these proposals and others will be on a competitive basis from the joint US-Egypt funding for science and technology. The workshop and the proposals are examples of the work needed to encourage the utilization of space products in developing countries. It is suggested that this could be the strongest motivation for developing next generation small remote sensing satellites in developing countries. The results of the use of indigenous satellite images in other countries are reported in various space technology 1 The author is thankful to the anonymous reviewer for suggesting the BSTI initiative as a possible framework for discussing the proposed AfricaSat project.
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and remote sensing conferences. One example of the uses of AlSat-1 satellite is given in Ref. [15]. 9. Conclusion In this paper we followed the progress and current status of the second phase of space programs in five developing countries in Africa and the Middle East. We traced the trends and directions of development of second generation satellites in these countries. The paths to development of second generation satellites ranged from moving along the same lines of the first satellites, i.e. as a means of transfer of satellite technology with higher specifications, to the development of a various mix of scaled down satellites, training model satellites and smaller Cubesats and Nano satellites. In several countries there is movement to develop subsystems and some components of small satellites. Effective efforts to develop a truly indigenous satellite have succeeded in the case of South Africa. Finally, the merits and advantages of a proposal to develop a regional joint satellite (AfricaSat) among African space faring countries are presented. References [1] R. Sandau, Status and trends of small satellite missions for Earth Observation, Acta Astronaut. 66 (2010) 1–12. [2] J.M.C. Romero, Technology, limitations and applications of space technology in developing countries, Adv. Space Res. 34 (2004) 2203–2208. [3] Woellert K., et al., Cubesats: cost effective science and technology platforms for emerging and developing nations. Adv. Space Res., 201010.1016/j.asr.2010.10.009. [4] U.M. Leloglu, E. Kocaoglan, Establishing space industry in developing countries: opportunities and difficulties, Adv. Space Res. 42 (2008) 1879–1886. [5] J. Susan, et al., Capacity building in emerging space nations: experiences, challenges and benefits, Adv. Space Res. 46 (2010) 571–581.
[6] G. Milne, et al., SUNSAT, Launch and first Six Month’s Orbital Performance, in: Proceedings of the Thirteenth Annual AIAA/USU Conference on Small satellites, SSC99-1-4, 1999. [7] S. Mostert, et al., Sumbandilasat—an operational technology demonstrator, Acta Astronaut. (63, 2008) 1273–1282. [8] A. Schoonwinkel, G. Milne, Managing a microsatellite development programme within a university environment, Technovation 17 (1) (1997) I-9. [9] R.A. Boroffice, The Nigerian Space Program: an Update, African Skies, No.12, October 2008. [10] L. Adetoro, and O. Aro, Nigeria Space Programs, IFAC Workshop on Aerospace Guidance, Navigation and Flight Control Systems, AGNFCS 2009, June 30–July 2, 2009, Samara, Russia. [11] U.R. Rao, Space technology in developing nations: an assessment, Space Policy 9 (2) (1993) 166–170. [12] M. Piso, Space sciences and technology research and education network for Central, Eastern, and Southern-Eastern Europe (invited lecture), ESA, Colloquium on Legal Aspects of Cooperation with Central and Eastern European Countries, Prague, 11–12 September, 1997. [13] Mohammed Shokr, Environment Canada, Toronto, Canada, Applications of Satellite Earth Observation Data to Environmental and Resource Monitoring in Egypt, Joint workshop for Space Technology and Geoinformation for Sustainable Development, Cairo, June 14–17, 2010. [14] El-Sayed Hermas and Islam Abou El-Magd, The National Authority for Remote Sensing and Space Sciences, land use mapping for path selection of strategic road using Egyptsat-1 imagery, Joint workshop for Space Technology and Geoinformation for Sustainable Development, Cairo, June 14–17, 2010. [15] S. Loumi, et al., Suspended matter model on Alsat-1 image by MLP network and mathematical morphology: prototypes by K-means, Int. J. Info. Commun. Eng. 3 (2007) 1. [16] M.B. Argoun, Recent Design and Utilization Trends of Small Satellites in Developing Countries, 61st IAC-2010, Prague, 27 September–1 October, 2010. [17] A. Abd-Elaziz, et al., EgyCubeSat-1 First Egyptian Remote Sensing Pico-Satellite, Minimizing Cost and Enhancing Resolution, in: Proceedings of the Thirteenth International Conference on Aerospace Sciences and Aviation Technology, ASAT-13, May 26–28, 2009. [18] J.O. Akinyede, F.D. Chizeu and Tsehaie Woldai, NIGERIASAT-1, in: Proceedings of the Fourth AARSE Conference On Geoinformation for Sustainable Development in Africa, October 14–18, 2002, Abuja, Nigeria. [19] /http://www.unoosa.org/oosa/en/SAP/bsti/index.htmlS.
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Acta Astronautica journal homepage: www.elsevier.com/locate/actaastro
Recent design and utilization trends of small satellites in developing countries$ Mohamed B. Argoun Cairo University, Department Aerospace Engineering, Egyptian Space Program, Egyptsat-1, Giza, Egypt
a r t i c l e i n f o
abstract
Article history: Received 24 April 2011 Received in revised form 24 July 2011 Accepted 30 July 2011 Available online 23 September 2011
Several small remote sensing satellites have been developed and launched during the last decade by several developing countries in Africa, the Middle East and East Asia. These satellites share among them several features; chief among them is that they were developed for use in developmental planning and to gain access to space technology. The first generation of those satellites had a relatively course resolution of about 30 m, but the second generation reaches a resolution of 2.5 m. This group of satellites also have ‘‘similar’’ designs, which stems from the fact that they were developed to achieve a similar purpose: introducing developing countries to space technology and application through small remote sensing satellites. The other side of building national space programs in developing nations is building the technological base for satellite manufacturing, building the infrastructure for operation and utilization of these satellites and most importantly building the user community and the user applications, which uses these results for sustainable development. This paper attempts to assess the degree to which these objectives were achieved for various satellites. In addition to these more ‘‘programmatic’’ aspects, the paper attempts to shed light, from published information, on some aspects of the recent trends in designs of small remote sensing satellites. & 2011 Published by Elsevier Ltd.
Keywords: Satellite Space technology Space programs Developing countries
1. Introduction Small satellites, mainly for remote sensing have emerged during the last two decades as an effective tool for enabling developing countries to enter the space field and benefit from space technology [1]. The concept of building indigenous small satellites in developing countries as a means of transferring space technology to these countries and expanding the base of satellite product use has emerged in the 1990’s. Several satellite manufacturing companies started offering this technology in the form of satellite technology transfer packages including training and know-how to developing countries. Several developing countries adopted this concept of transfer of space technology through building of small
$
This paper was presented during the 61st IAC in Prague. E-mail address: [email protected]
0094-5765/$ - see front matter & 2011 Published by Elsevier Ltd. doi:10.1016/j.actaastro.2011.07.024
satellites and acquiring the technology and training in the process. A number of studies have appeared, which report and examine the emergence and evolution of space programs in developing countries on a regional basis. For example, Romero [2] examines and discusses the space programs in five Latin American developing countries. However, as the development of these space programs progressed, it became clear that the sustainability of the process depends more on the stimulation of demand of space products than on the technical specifications and the initial success of building the first satellite. The first satellites were usually built by the satellite manufacturing company, which is transferring the technology. The second satellite and the following space products (smaller satellites, satellite components, etc.) are the ones typically built by the developing country. To gage the success of a developing country space program we have to examine the extent to which its satellites and components are built by local and indigenous entities.
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We argue here that the building of the second generation satellites will not be attractive unless there is significant utilization of the first satellite products. Therefore, there is a need to concentrate on spreading the use of remote sensing satellite products, expand the satellite imagery user community and create new value added products in order to show the economic benefits and sustain the momentum for developing countries to enter into the space field. Moreover, the government interest in building the second generation satellites frequently wanes and sometimes stops after the immediate return from launching the first satellite is obtained. In this case the scientific space community must resort to other means to maintain the momentum of acquiring and building the space technology base in the developing country. Such means include building smaller satellites (Cubesats) [3], building satellites in universities, building subsystems rather than complete satellites and finally encouraging research oriented at design of satellite components and payloads. In this paper we examine the routes taken by five developing countries in Africa and Middle East in achieving the transition from building their first satellites through international space companies under a technology transfer and training programs to producing the second generation satellites indigenously. The countries considered are Algeria, Egypt, Nigeria, South Africa and Turkey. We examine some of the paths followed for enhancing the technical capability of these countries to build small satellites and discuss the factors and measures needed to maintain the initial momentum, which accompanied the entry of several developing nations into the space field. The second section of the paper considers the common objectives of space programs in developing countries. In the third section we briefly examine some technology transfer aspects in the space programs under consideration. This is also extended into the fourth section. In the fourth section we present the first generation satellites in more detail. The fifth section deals with the second generation satellites and discusses the paths taken by different countries to implement this phase of their space programs. We also discuss various design changes and take a look at the technical changes and programmatic ways of entering into this second phase. In Section 6, we present an important initiative for cooperation in building
a joint small remote sensing satellite (AFRICASAT) based on the experience and know how those developing countries gained in the first phase of developing their national space programs. The last section deals with the utilization of satellite products, which we stress is an essential element in ensuring the sustainability of space programs in developing countries.
2. Common features and objectives of space programs in developing countries When space programs started in the developing countries in Africa and the middle east they had the following common objectives. 2.1. Build and launch first national satellite. 2.2. Acquire knowledge and know-how by building indigenous satellites. 2.3. Transfer knowledge and know-how to local industry. 2.4. Engage national universities and research centers in space research and technology. 2.5. Increase the utilization of space applications and products. 2.6. Establish a National Space Agency. Table 1 shows general features of space programs in the five developing nations considered in this study. The agencies within which these programs were developed are: i) Algerian Space Agency. ii) National Space Research and Development Agency—Nigeria. iii) National Authority for Remote Sensing and Space Sciences, NARSS, Egypt. iv) Stellenbosch Univ., South Africa. v) Space Technologies Research Institute, Turkey. Approximately a decade has passed since the various countries launched their respective space programs. These space programs have evolved generally along similar paths with some variations due to varying conditions in each country. In the following we discuss briefly the status and achievement of each of the space programs under study.
Table 1 General features of Space Programs in five developing nations. Item
Algeria
Nigeria
Egypt
South Africa
Turkey [4]
Year space program started First satellite name Launch date Ground resolution Company/agency/ country cooperated with Agency supervising Status of second generation satellite
2002
1999
1999
1991
2001
Alsat-1 November 2002 32 m Surrey, UK
NigeriaSat-1 September 2003 32 m Surrey, UK
Egyptsat-1 17/4/2007 7.8 m Yuzhnoye/Ukraine
SunSat February 1999 15 m Indigenous
BilSat 2003 27.6 m SSTL,UL
ASA (i) Alsat-2A Launched July 2010
NASRDA (ii) Nigeriasat-2 planned for launch in 2011
NARSS (iii) Not yet started
SU (iv) SumbandilaSatlaunched 17 September 2009
UZAY (v) Manufactured and shipped for launch 7/2011
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3. Technology transfer within the space programs The first satellites were generally very successful. Their success however was more a testament to the capabilities of the companies that manufactured them than a testament to the strength of the space programs in the developing nations. That last aspect can be measured by the number of engineers and specialists who were trained, the level they achieved in technology transfer and the share they contributed in the next generation satellites. In the case of Egyptsat-1 the number of engineers and specialists trained was 64 covering virtually all areas of design, manufacturing and testing of small satellites. The experience transferred to them is recorded in a large number of documents written for that purpose. The structural and engineering models of the satellite were transferred to Egypt and are used for training. Test equipment used for testing the satellite components and subsystems was transferred to Egypt and erected in an Engineering Model Lab where a functioning model of the satellite is operating and used for training and troubleshooting. A team of satellite operators comprising about 30 engineers was trained for operating the satellite both on the control and the receiving ends and are currently operating the satellite independently. Each of the regional developing countries, which started a space program in the late nineties of the last century, has launched a functional first satellite. In Table 2 we provide a brief list of the salient technical features of the first remote sensing satellites in the five nations considered. The technology transfer aspect of the remaining space programs is discussed in the following section.
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The satellite included a GPS receiver, laser reflectors, magnetometers, star camera, Amateur Radio communications and a 15 m resolution, 3456 pixel, 3-band push broom imager. The satellite structure adopted a modular tray structure where each tray included some elements of the various subsystems (Fig. 2). The optical system has a diameter of 10 cm and a focal length of 570 mm. The pixel size of 10.7 mm translates into 15.01 m from 800 km. The swath width is 3456 pixels 15.01 m ¼51.9 km. An 8 bit image data handling system is used including a 64 Mbyte RAM disk for onboard image storing. The attitude control system employed reaction wheels during imaging and magnetorquers for course attitude control. An extendable tip mass is used for attitude stabilization. Several images were successfully taken and transmitted to the ground from SUNSAT satellite. Some of these results as well as more details on the technical aspects of the satellite are reported in [6]. SunSat failed in orbit a short period after launch in 1999 but South Africa benefited from the developed technology, which reflected in the first indigenous second generation satellite in Africa: Sumbandilasat [7]. 4.2. AlSat-1 The first phase of the Algerian Space Program depended on training and know-how transfer to a core group of Algerian engineers who participated in design and building of AlSat-1. The satellite Al-Sat-1 is the first generation Algerian satellite and is designed and built by
4. Overview of first generation satellites in the region 4.1. SUNSAT—the first satellite in Africa In the early days of the development of small satellite technology transfer activity South Africa developed and launched the first satellite in all developing countries namely SunSat satellite, developed by Stallenbush University. SUNSAT was launched on a NASA sponsored Delta II launch on February 23, 1999 (Fig. 1).
Fig. 1. SUNSAT in-orbit configuration.
Table 2 Developing countries’ first satellites. Country
Algeria
Nigeria
Egypt
South Africa
Turkey
Satellite Name Weight (kg) Orbit-sun synchronous Multispectral/Panchromatic Ground resolution (RBG) (m) Swath width Near Infra Red (NIR) Operational Status
Algeria Sat-1 100 680 km 32
NigeriaSat-1 100 686 km 32
Egyptsat-1 165 668 km 7.8
SUNSAT 64 – 15
BilSAT 129 686 km 26.7/12.6
10 m multi-spectral, 2.5 m panchromatic
52 km – Problems in orbit reported July 1999 6.5 m
– 26.7 m –
Specifications of next generation satellite payload
45 km 39 m Lifetime expired after 39 months in orbit 2.5 m multispectral
640 km 600 km – – Operational as of 2009 Lifetime expired 5 m multi-spectral, 2.5 m panchromatic
–
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Fig. 3. Alsat-1 structure.
country’s national Earth observation needs. The technical features of NigeriaSat-1 are similar to those of AlSat-1 and BiLSat-1. The NigeriaSat-1 satellite was launched on the 27th of September, 2003 [18]. 4.4. Turkey’s space program first phase Fig. 2. SUNSAT Tray structure.
SSTL Ltd. The satellite carries a 32 m ground resolution with a swath width of 600 km. The satellite has dimensions of 60 60 60 cm3 and weighs 98 kg. The satellite attitude control system has 2 ADCS modules each comprises one magnetometer, two sun-sensors and three coiled magnetorquers. The satellite has two booms, which help in stability. The satellite is equipped with a propulsion system with 50 mN thrust and two tanks with a 2.5 litre capacity for each. The optical payload is supported by a total storage capacity of two 0.5 Gbytes of data, which could be downloaded at 8 Mbps (Fig. 3). 4.3. NigeriaSat-1 The first phase of the Nigerian Space Program included building of the NigeriaSAT-1 satellite by SSTL Ltd., and training of 15 Nigerian engineers in a Know-How Technology Training (KHTT), which extended over a fifteen month period of training in the design and building of all subsystems of the NigeriaSat-1 spacecraft. The NigeriaSat-1 spacecraft is similar to AlSat-1 and BiLSAT, which were built for Algeria and Turkey by the same company. The satellite, as the other two satellites, is part of the Disaster Monitoring Constellation, DMC, a collaborative effort for monitoring of natural and man made disasters all over the globe as well as satisfying the
The Turkish space technology transfer team comprised a core of 8 engineers in different disciplines alongside four M.Sc. students and a number of academic staff and technicians at TUBITAK UZAY, TUBITAK Space Technologies Research Institute. The core team gained their experience through working on the development of the engineering model and testing of the BILSAT flight model. Turkish involvement in BILSAT development included two payloads designed and built by Turkish team. The first, named COBAN, is a nine-band low resolution multispectral imager. The second, named GEZGIN, is a DSP based image processing module, which is used to compress images taken by BILSAT-1’s on board cameras [5]. The BILSAT satellite itself on which the Turkish team received their first phase training and know-how is a 130 kg satellite built by SSTL Ltd. and carries a 32-meter resolution imager in 3 spectral bands, in addition to the experimental payloads COBAN, GEZIN built by the Turkish team. The satellite was launched on 27th September, 2003 (Fig. 4). 4.5. First Egyptian satellite: Egyptsat-1 EgyptSat-1 is the first Egyptian remote sensing satellite. It is designed and built by the Ukrainian firm Yuzhnoye SDO. The satellite was successfully launched on 17th April, 2007. The satellite was part of a program to transfer satellite technology to Egypt through partnership with an advanced space faring nation. There was a strong element of training
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Fig. 4. Bilsat 1 [SSTL].
and learning by participation from the Egyptian side. Sixty four Egyptian engineers and specialists received their experience this way through participation in all phases of the satellite design, building, testing, launch and operation. Here are some of the salient technical features of the satellite. The Egyptsat-1 satellite is a three axes controlled satellite with resolution of 7.8 m on the main multispectral scanner. The satellite payload consists of two cameras and a store and forward communication payload. Egypt-Sat-1 main architecture was the star topology architecture based on a central command data handling subsystem, which organizes the data handling between all satellite subsystems, and between satellite and ground (Figs. 5 and 6). The EgyptSat-1 satellite comprises the following Subsystems and components:
Fig. 5. EgyptSat-1 subsytems.
Satellite structure Power subsystem (PSS) Platform command and data handling subsystem (PCDHS)
Attitude determination and control subsystem (ADCS) processing unit four reaction wheels (RW) J star sensor (SS) J magnetometer (MM) J 3 magnetorquers (MT) J angular velocity meter (Gyro) Communcation subsystem (CSS) J S-Band J X-Band Global positioning system (GPS) Telemetry module (TM) Seperation transducers J J
Fig. 6. General view of EgyptSat-1.
Payload J J J
Payload Command and Data Handling Subsystem (PLCDHS) Multi-band Earth Imager (MBEI) Middle-IR Earth Imager (MIER)
Table 3 above summarizes the salient technical features of Egyptsat-1.
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Table 3 EgyptSat-1 main characteristcs and features. Feature
Value
Feature
Satellite total mass (kg) Payload subsystem mass (kg) Scanner type Resolution: multispectral scanner Swath width Orbit type Altitude (km) Inclination (deg) Ascending node local time Attitude control Subsystem Type Accuracy at imaging Angular rate of stabilization at imaging (deg/s) Tilting- pitch and roll Attitude determination
165
Lifetime full performance 3 years reduced performance 2 years Middle Infra-Red Earth Imager (MIREI) Resolution- NIR Scanner 39 m Swath width – Power subsystem Maximum 270 Daily average 53 Solar cells deploayable Communication system S-band control frequency 2089 Mhz S-band telemetry 2268.6 Mhz X-band downlink 8192 Mhz Launch vehicle Dneper-1
49 Push Broom 7.8 m 46 km Sun synchronous 668 km 98 22:30 Active – 3 axes 0.21 0.005 7 351 Star sensor based
5. Second phase of space programs in developing countries All of the five developing countries studied in this paper have successfully launched and operated their first satellites and have entered the second phase of their respective space programs. Those first satellites were built within satellite technology transfer programs conducted by partners from advanced space faring countries with the exception of South Africa, which had a first generation indigenously built satellite, SunSat. In the following we discuss the various approaches taken by these countries to build their second generation satellites. Six directions in satellite and subsystems design and development can be identified among developing nations in the region after the launch of their first satellite. A seventh track is proposed through regional cooperation between the developing countries with the support of an international element represented by the UN office for outer space. The current approaches for building second generation satellites in developing countries are as follows: 5.1 Building larger and more powerful satellites in close cooperation with more advanced space faring countries. 5.2 Development of indigenous satellites based on the experience gained in first satellites. 5.3 Building similar versions of the first satellite to preserve the technology base, replace the existing or expired satellites or as training and technology transfer models. 5.4 Building scaled down versions of the first satellite (e.g. University satellites). 5.5 Building smaller types of satellites as a building stone of experience and acquisition of know-how (CubeSats and Nano Satellites). 5.6 Building subsystems and components. In addition to building satellites some developing countries have taken the path of building satellite
Value
components and subsystems either to enhance the technological and industrial base or simply because it is a lower funding sub-track. Finally the approach of building a joint African satellite among developing space faring countries in Africa is proposed as a feasible and useful option for sustaining and supporting the space programs in developing countries. In the following we discuss the different approaches taken by developing countries in the Africa and Middle East region in the design and development of second generation satellites. 5.1. Larger and more powerful satellites: Nigeria and Algeria were among the developing nations in Africa, which followed the direction of building larger and more powerful satellites. These two countries adopted the approach of building the second satellite in close cooperation with partners from well developed space faring nations. Nigeria chose to build NigeriaSat-2 with SSTL of UK. The satellite is planned to be launched in the first quarter of 2011. NigeriaSat-2 is a powerful remote sensing satellite, which weighs 285 kg with ground resolution of 2.5 m panchromatic and 5 m multispectral [5]. The satellite is equipped with a 32 m imaging mode to be compatible with the Disaster Monitoring Constellation (DMC), an initiative, which has five countries and five satellites participating for joint monitoring of disaster areas. The spacecraft is based on the SSTL advanced SSTL-300i satellite platform. The second generation high resolution Algerian satellite was launched on July 12, 2010. The satellite named AlSat-2A is designed and built by EDAS/Astrium Corporation and is based on its AstroSat-100 platform. The satellite has a ground resolution of 2.5 m. 5.2. Development of indigenous satellites 5.2.1. South Africa The second track in satellite technology development in African and Middle Eastern countries is to build the country’s
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indigenous follow up satellite based on the country’s own experience and capabilities. This approach is taken by South Africa, which has a much stronger industrial base than the other four countries that have satellite technology transfer programs in the form of the SumbandilaSat [7].
5.2.2. Turkey The other indigenous satellite being built in the region is the Turkish satellite RASAT [4,5], an experimental satellite, which is built within the scope of the second phase of the Turkish Space Program. The satellite is part of a development project for a LEO satellite with 7 m ground resolution. ‘‘RASAT’’ was designed and manufactured in Turkey by the space division of the Scientific and Technological Research Council of Turkey (TUBITAK).
5.2.3. Algeria Algeria is planning to build Alsat-2B satellite in collaboration with Astrium using its 30 engineers and specialists who received training during the process of building AlSat2A. The agreement signed in 2006 by CNTS (Algerian National Space Technology Center) with EADS/Astrium calls for 2 satellites. The second of those satellites Algeriasat-2B will be integrated in Algeria within the small satellite development center (UPDS) in Oran, Algiers [5].
5.2.4. Egypt In the case of Egypt the original strategy of the space program called for building EgyptSat-2, which is a developed version of Egyptsat-1 with enhanced resolution and increased component of local design and manufacturing. Egyptsat-2 was planned to have 60% local component of design and manufacturing. The most technically feasible satellite design is a modified and more evolved version of Egyptsat-1 with a resolution of about 5.4 m. This is the resolution thought to preserve, absorb and deepen most of the technology used in Egyptsat-1. In this satellite the payload will be different from that of Egyptsat-1 but most of the satellite subsystems will be an extended version of Egyptsat-1 subsystems. In this future satellite the Store and Forward payload is expected to be removed. The satellite is likely to be built by NARSS with limited foreign cooperation. Currently, work has not started in Egyptsat-2 beyond the initial phases of mission analysis and preliminary design and it is doubtful that the satellite will be launched in the next year i.e. 2012 as was originally planned. Other ideas of a satellite with 2.5 m resolution are being discussed, but in this case the indigenous content will be very limited. In the absence or delay of a decision to build a second generation satellite in a developing country the technology base of a space industry might erode. To avoid such erosion and to preserve the momentum and know-how several alternative approaches are available to a developing country. The alternatives are in the form of similar satellites, university satellites, Cubesats and building of satellite subsystems. These alternatives are proposed for the Egyptian space program and some are actually implemented.
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5.3. Building similar versions of the first satellite to preserve the technology and replace expired satellites This approach applies in the cases of Egypt and Nigeria. Egypt has recently lost contact with its first generation satellite EgyptSat-1 and needs a replacement satellite. A replacement satellite can be built indigenously in Egypt within the current technical and infrastructure capability of the country. No major changes in this case are expected to be introduced to the design of Egyptsat-1 except for the removal of the Middle Infra Red scanner and the Store and Forward payload and associated changes. The rationale for this alternative is that the cycle of technology transfer is not complete without building an indigenous satellite based on the heritage and technology of the first satellite EgyptSat-1. Building a similar satellite preserves the heritage of EgyptSat-1, builds on it and enhances the process of technology transfer. The heritage of Egyptsat-1, which supports this approach, is presented in the following: a) A proven satellite design, which shortens the cycle of development. b) Proven satellite building and testing technology and methods acquired through the first experience. c) Documentation of all design drawings, calculations, software, testing methods and results, which are provided with the original Egyptsat-1 satellite. d) Test equipment of all satellite subsystems. e) Engineering model laboratory, which includes a full functioning version of the satellite Egyptsat-1 together with test equipment and connections for operation and troubleshooting of all subsystems. f) A large pool of trained engineers in satellite design, testing and operation. Building a similar satellite to EgyptSat-1 has the following advantages: a) It falls within the capability of the trained team and can be built completely indigenously, possibly with some minor assistance from abroad. b) It deepens and enhances the technology base by full utilization and absorption of the transferred technology. c) Some designs can be used as are in the original satellite thus reducing cost, time and effort. d) Low cost, being built and tested in the country. e) It provides a replacement to the first operational satellite EgyptSat-1. In the case of Nigeria the rationale for building a similar satellite is different. It is built alongside NigeriaSat-2. Built as a technology transfer and training model, this mode of enhancing the technology transfer process depends on building a similar model to the satellite built by the technology transferring company for hands on training. The training model is named NigeriaSat-X and is developed with the participation of twelve Nigerian engineers and scientists at the premises of SSTL [9,10].
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The satellite, which will be launched alongside NigeriaSat-2, has a 22 m resolution and is compatible with the specifications of the DMC satellites. 5.4. Build a scaled down version of first satellites (university satellites) Both SunSat [6] and Sumbandilasat [7,8] satellites of South Africa are university built satellites. Schoonwinkel and Milne [8] give some useful experiences on building satellites in a university environment. Building a scaled down version of the first satellite to preserve and enhance the transferred technology is the basis of Egypt’s UNIVERSAT, which is discussed in the following section. This satellite is proposed to be built cooperatively by several Egyptian Universities with Cairo University taking the lead. The objectives of the satellite project are several folds: 1. Preserve the design and technological heritage of Egyptsat-1. It is well known that technology transfer is not complete without the hands-on practical experience obtained through building and testing of a complete indigenous satellite. 2. Expand the technological base of space industry by transferring the technology to the universities, which are the largest pool of scientific personnel in a country like Egypt. 3. Gaining any detailed hands-on experience of building satellite subsystems and assemblies, which was not fully obtained during the first phase of the space program i.e. the phase of technology transfer by direct contact with the transferring agent. The UNIVERSAT satellite is planned to carry a single payload consisting of a 10 m ground resolution optical scanner. The satellite weight is required to be in the 80 kg range (EgyptSat-1 is 165 kg). UNIVERSAT is hoped to provide an indigenously built basic platform for future Egyptian satellites and missions. The funding for the project is sought from Cairo University, NARSS and STDF (Science and Technology Development Fund in Egypt). 5.5. Build CubeSats and other smaller satellites Cubesats are a useful educational and technology transfer tool for satellite technology. This type of small satellites is gaining wide acceptance in universities and in space programs of developed and developing nations alike. In Egypt there is a project for building Cubesats with joint funding from STDF of Egypt and the European Union [17]. 5.6. Build critical satellite subsystems In order to have a serious indigenous satellite building capability a developing country or an agency in that country must be able to build and test satellite subsystems successfully. Among the usual satellite subsystems two subsystems present engineering and technological challenges, namely the payload and the ADCS. As a step toward building indigenous satellites, whether it is a replacement satellite
to Egyptsat-1 or UNIVERSAT there is a joint project between NARSS and Cairo University to design, build and test the two critical subsystems: the payload and ADCS. Once this project proceeds toward implementation other subsystems will be built and tested in a second phase of the project. The third phase will be assembly and integration of the engineering model. In Turkey a similar approach is taken where an R&D sub-program is established alongside the main BiLSAT program to propose, design and build two of the BilSAT research and development payloads: a nine channel medium resolution imager named COBAN and a high performance digital signal processing card named GEZIN, both of which were manufactured in Turkey [4].
6. International and regional cooperation International space projects is an effective way of sharing the technology and lowering cost. In case of developing nations we also add the motivation of sustaining the momentum of budding space programs. As mentioned in [2], Rao [11] has suggested that developing countries should establish ‘‘their own regional and multilateral programs’’ for promoting space technology. In [12] a small satellite project was proposed to be developed by Eastern and South-Eastern European countries. The objectives, designs and main features of a regional satellite project suitable for developing countries of a certain region depends on certain features and factors specific to that particular region. Among these features and factors is the number of countries participating, average or overall level of industry in those countries and the degree of political maturity, which allows regional cooperation rather than unnecessary competition in certain fields. Also, former or existing cooperation programs play a role in promoting wider scope projects. In case of satellite projects the common features of first generation satellites is an asset. For the region of Africa there are common features in the development of their space programs that motivate proposing a joint satellite project. The motivation and objectives for the proposed initiative are as follows: 1. To guarantee the continuation and momentum of developing space industry in African nations by adding an international element to their space programs. 2. To provide a basic platform for various African countries satellite missions. 3. To provide a pool of data for use of space technology in development of Africa. 4. To enhance the process of technology building by providing a feasible technical challenge of building and testing a subsystem and integrating the overall satellite. 5. A step toward regional and international collaboration, which helps establish the norms of such cooperation in the future between developing countries. 6. To provide a low cost alternative for continuation of the space programs for countries, which lack the funding.
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7. To gain experience and fine tune current capabilities in scientific international projects management. 7. AfricaSat: a joint satellite proposal among all space faring developing countries in Africa AfricaSat is a proposed initiative, which was first presented at the 61st International Astronautical Congress IAC in Prague, 27 September–1 October, 2010 [16] to enhance effective satellite technology transfer to African Nations and support space programs currently ongoing at those countries. The countries expected to benefit and participate in this initiative are South Africa, Nigeria, Algeria and Egypt. A representation by the United Nations Office of Outer Space is thought to provide coherence and adds to the success of the initiative. This proposed satellite development is thought to enhance the existing African Resource Management Constellation ARMC initiative already in progress. The AfricaSat platform once developed could be the base for future satellites within the ARMC. 7.1. Technical features of the proposed satellite Technical features of the satellite are selected to suit the current level of know-how and technology acquired by the intended developing countries. 1. The proposed satellite is a small (80 Kg) satellite, which carries a 10 m resolution multispectral imager. This is an intermediate resolution between the high resolution of 2.5 m and 6.5 m carried by the second generation advanced satellites and the 32 m resolution of some of the first generation satellites. 2. The technical features of the various subsystems should reflect the evolved features and designs of the four satellites leading to this joint satellite, namely: Sumbandilasat, NigeriaSat-2, AlgeriaSat-2 and Egyptsat-1. The process and steps of realizing this project are envisaged as follows: 1. The initiative will be presented and discussed in various small satellite conferences and meetings where fine tuning and consensus will be reached. 2. The overall satellite design will be made by a system engineering and overall design group formed from representatives of all nations. 3. Each country will build a subsystem of the satellite in its own territory. Project management: 1. A management and system engineering group will be formed with representatives from all countries. 2. Management meetings will be held in different countries successively once every four months. The progress reports will be presented and the necessary decisions will be made. 3. A review and quality control process will be instated.
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Funding: Each country will fund its own activity and will build the necessary capacity to conduct this activity. The role of UNOOSA: The success of such an initiative requires the role of the United Nations Office of Outer Space Affairs as a binding and monitoring agent. The United Nations Office of Outer Space Affairs UNOOSA is implementing the United Nations Program on Space Applications. Under that program a new initiative dedicated to support capacity building in basic space technology development was recently launched. The initiative is called Basic Space Technology Initiative BSTI [19]1. 8. Utilization of indigenous small satellites in developing countries As mentioned earlier, the utilization of satellite images in national development plans in any developing country is the strongest factor in supporting the cause of sustainable space programs’ development. For this reason the space authorities in developing countries must direct a portion of its efforts to spread the use of space products and introduction of new value added means of creating the market for space technology and hardware products. The level of utilization of space products, namely images and data is generally low in all of the developing nations. There is no available metric for measuring the level of utilization of images. One suggested measure is the number and topics of publication in the various conferences and publication journals in the field, and specifically the regional conferences. In Egypt a joint US-Egypt workshop was held under the title ‘‘Joint US-Egypt workshop for Space Technology and Geoinformation for Sustainable Development’’ Cairo, June 14–17, 2010 to present and encourage the results of using Egyptsat-1 and similar satellites for development. More than forty papers were presented mostly displaying results of using Egyptsat-1 images in various applications such as crop measurement, water resource management and archeology among others. We list 2 papers [13,14] presented in this workshop as examples of work that started to build up using Egyptsat-1 images. Many other examples are found in that workshop and on the website. Along the same line some 24 proposals for projects utilizing the space products of Egyptsat-1 and similar satellites were suggested during the workshop. The funding of these proposals and others will be on a competitive basis from the joint US-Egypt funding for science and technology. The workshop and the proposals are examples of the work needed to encourage the utilization of space products in developing countries. It is suggested that this could be the strongest motivation for developing next generation small remote sensing satellites in developing countries. The results of the use of indigenous satellite images in other countries are reported in various space technology 1 The author is thankful to the anonymous reviewer for suggesting the BSTI initiative as a possible framework for discussing the proposed AfricaSat project.
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and remote sensing conferences. One example of the uses of AlSat-1 satellite is given in Ref. [15]. 9. Conclusion In this paper we followed the progress and current status of the second phase of space programs in five developing countries in Africa and the Middle East. We traced the trends and directions of development of second generation satellites in these countries. The paths to development of second generation satellites ranged from moving along the same lines of the first satellites, i.e. as a means of transfer of satellite technology with higher specifications, to the development of a various mix of scaled down satellites, training model satellites and smaller Cubesats and Nano satellites. In several countries there is movement to develop subsystems and some components of small satellites. Effective efforts to develop a truly indigenous satellite have succeeded in the case of South Africa. Finally, the merits and advantages of a proposal to develop a regional joint satellite (AfricaSat) among African space faring countries are presented. References [1] R. Sandau, Status and trends of small satellite missions for Earth Observation, Acta Astronaut. 66 (2010) 1–12. [2] J.M.C. Romero, Technology, limitations and applications of space technology in developing countries, Adv. Space Res. 34 (2004) 2203–2208. [3] Woellert K., et al., Cubesats: cost effective science and technology platforms for emerging and developing nations. Adv. Space Res., 201010.1016/j.asr.2010.10.009. [4] U.M. Leloglu, E. Kocaoglan, Establishing space industry in developing countries: opportunities and difficulties, Adv. Space Res. 42 (2008) 1879–1886. [5] J. Susan, et al., Capacity building in emerging space nations: experiences, challenges and benefits, Adv. Space Res. 46 (2010) 571–581.
[6] G. Milne, et al., SUNSAT, Launch and first Six Month’s Orbital Performance, in: Proceedings of the Thirteenth Annual AIAA/USU Conference on Small satellites, SSC99-1-4, 1999. [7] S. Mostert, et al., Sumbandilasat—an operational technology demonstrator, Acta Astronaut. (63, 2008) 1273–1282. [8] A. Schoonwinkel, G. Milne, Managing a microsatellite development programme within a university environment, Technovation 17 (1) (1997) I-9. [9] R.A. Boroffice, The Nigerian Space Program: an Update, African Skies, No.12, October 2008. [10] L. Adetoro, and O. Aro, Nigeria Space Programs, IFAC Workshop on Aerospace Guidance, Navigation and Flight Control Systems, AGNFCS 2009, June 30–July 2, 2009, Samara, Russia. [11] U.R. Rao, Space technology in developing nations: an assessment, Space Policy 9 (2) (1993) 166–170. [12] M. Piso, Space sciences and technology research and education network for Central, Eastern, and Southern-Eastern Europe (invited lecture), ESA, Colloquium on Legal Aspects of Cooperation with Central and Eastern European Countries, Prague, 11–12 September, 1997. [13] Mohammed Shokr, Environment Canada, Toronto, Canada, Applications of Satellite Earth Observation Data to Environmental and Resource Monitoring in Egypt, Joint workshop for Space Technology and Geoinformation for Sustainable Development, Cairo, June 14–17, 2010. [14] El-Sayed Hermas and Islam Abou El-Magd, The National Authority for Remote Sensing and Space Sciences, land use mapping for path selection of strategic road using Egyptsat-1 imagery, Joint workshop for Space Technology and Geoinformation for Sustainable Development, Cairo, June 14–17, 2010. [15] S. Loumi, et al., Suspended matter model on Alsat-1 image by MLP network and mathematical morphology: prototypes by K-means, Int. J. Info. Commun. Eng. 3 (2007) 1. [16] M.B. Argoun, Recent Design and Utilization Trends of Small Satellites in Developing Countries, 61st IAC-2010, Prague, 27 September–1 October, 2010. [17] A. Abd-Elaziz, et al., EgyCubeSat-1 First Egyptian Remote Sensing Pico-Satellite, Minimizing Cost and Enhancing Resolution, in: Proceedings of the Thirteenth International Conference on Aerospace Sciences and Aviation Technology, ASAT-13, May 26–28, 2009. [18] J.O. Akinyede, F.D. Chizeu and Tsehaie Woldai, NIGERIASAT-1, in: Proceedings of the Fourth AARSE Conference On Geoinformation for Sustainable Development in Africa, October 14–18, 2002, Abuja, Nigeria. [19] /http://www.unoosa.org/oosa/en/SAP/bsti/index.htmlS.