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Novel micro aircraft inspired by insect flight
Abstracts / Comparative Biochemistry and Physiology, Part A 146 (2007) S129–S141
S133
A7.13 Tensile water technology — An effort to learn from trees
artificial muscles will demonstrate how man and robots can gently work together in the future.
C. Toetzke, H. Tributsch, N. Szabo, (Hahn-Meitner-Institut Berlin, Germany)
doi:10.1016/j.cbpa.2007.01.254
2 layer was used to simulate the evaporative sites of leafs. During evaporation, the structural changes of the confined water have been observed by means of ATR-infrared spectroscopy. The shifting absorption spectra have been interpreted in terms of structural transitions towards greater water cluster possessing a higher degree of cross linking. The findings point to the formation of the tensile water inside the pores resulting from the evaporation process. Another experimental set up was used to simulate the water ascent in trees. A nanoporous evaporation body was mounted on top of a long glass capillary. After thorough cleaning the system was filled with water and the lower end of the capillary submerged into mercury. While evaporation took place from the nanopores mercury was pulled up inducing a pressure drop inside the capillary. The water was stressed well into the domain of negative pressure before cavitation occurred and the water column broke. This setup can be used to identify morphologic key factors for possible technical applications.
A7.15 Optic flow based autopilot: From insects to rotorcraft and back
doi:10.1016/j.cbpa.2007.01.253
A7.14 Bionics — Innovative structural solutions in fluiddynamics and robotics R. Bannasch, (Evologics Berlin, Germany) Looking at the functional anatomy of living organisms trough the eyes of an engineer one can discover a wealth of inspiring, evolutionary optimised and practically well proven structural solutions suitable to stimulate also a new concept for the development of modern high-tech constructions. The paper will give some examples to illustrate how nature makes use of elastic materials and self-adaptive structures in order to increase functional reliability and fault tolerance dramatically as well as to reduce weight, energy consumption and neuronal control in operation. The application of similar concepts to engineering leads to an approach recently characterized by terms like “intelligent embodiment” or “morphological intelligence”. Artificial covering feathers were successfully tested in aircrafts to prevent stall in crucial flight manoeuvres by blocking the reverse flow at the suction side of the wings at high angles of attack. The unusual self-adaptive behaviour of fish fins (Fin Ray Effect ®) leads to a new concept in adaptive wing profiles and facilitated the design of an artificial manta ray with a very “organic” swimming behaviour. Other useful applications of the Fin Ray Effect ® are e.g. a backrest self-adapting to the shape of the human body and a new type of grippers able to handle fragile objects with variable shapes. Finally, a life-sized humanoid robot with
N. Franceschini, F. Ruffier, J. Serres, (CNRS and University of the Mediterranean, France) When insects are flying forwards, the image of the ground sweeps backwards across their ventral viewfield, forming an ‘optic flow’, which depends on both the groundspeed and the height of flight. To explain how these animals manage to avoid the ground using this image motion cue, we suggest that insect navigation hinges on a visual feedback loop we have called the optic flow regulator, which controls the vertical lift. To test this idea, we built a micro-helicopter equipped with a fly-inspired optic flow sensor and an optic flow regulator. We showed that this fly-by-sight microrobot can perform exacting tasks such as take-off, level flight and landing. Our control scheme accounts for many hitherto unexplained findings published during the last 70 years on insects' visually guided performances, including the facts that honeybees descend under headwind conditions, land with a constant slope and drown when travelling over mirror-smooth water. Our control scheme explains how insects manage to fly safely without any of the instruments used onboard aircraft to measure the height of flight, the airspeed, the groundspeed, and the descent speed. An optic flow regulator could be easily implemented neurally. It is just as appropriate for insects (1) as it would be for aircraft (2,3). (1) Franceschini et al., Curr. Biol. (2007, in press). (2) Ruffier, F., Franceschini, Rob. Aust. Syst. Bot. 50, 177–194 (2005). (3) Franceschini et al., CNRS International Patent: PCT Nb 28 44 607 (2002). doi:10.1016/j.cbpa.2007.01.255
A7.16 Novel micro aircraft inspired by insect flight D. Lentink, N. Bradshaw, S.R. Jongerius, (Wageningen University, The Netherlands) A team of biologist and engineers of Wageningen University, Ruijsink Dynamic Engineering and Delft university of Technology has developed “Delfly”, a flapping micro air vehicle (MAV) inspired by Insect flight. Delfly has flexible saillike wings and as a result the wings deformation depends on both wing inertia and aero-elasticity. Flapping wings are able to generate lift based on delayed stall mechanisms. Delfly has this
S134
Abstracts / Comparative Biochemistry and Physiology, Part A 146 (2007) S129–S141
capability; it can flap its wings at angles of attack well beyond stall-without loss of lift, a phenomena utilized by insects. As a result Delfly can fly both fast and hover, recently it has even flown backwards. The aerodynamic optimization of Delfly is carried with a force balance and a total power-measurement set-up in a vacuum chamber. With this set-up we can optimize the thrust and lift generation with respect to total power. The vacuum chamber allows us to determine both the inertial and aerodynamic power contribution. The chamber also allows us to study wing deformation; is the deformation of the flexible wing dominated by inertial or aerodynamic force? To quantify wing deformation time-resolved we use high speed video. Finally we will elucidate our future plans for the development of NanoFly, a flapping NAV with a wing span of less than 2”. For its wing design we analyzed dragonfly wings using 3D microCT scans, image processing and the Finite Element Method. Based on this analysis we pre-designed miniature carbon fiber wings and a micro production process to fabricate aeroelastically tailored flapping wings inspired by insect flight. doi:10.1016/j.cbpa.2007.01.256
(FE) and interferometric (IF) analyses and on atomic force microscopy (AFM) of close parallel, lyriform slit arrays. FE analysis. Even minor morphological variations of slit arrangement affect slit interaction and thus stimulus transformation. The compressive slit face displacement D, which leads to nervous excitation, is mainly influenced by slit length l and load direction F whereas a slit's aspect ratio (20–100) is hardly relevant. At lateral distances between slits typical of lyriform organs (S = 0.03 l) their lateral shift ? considerably influences slit compression. White light IF, micro force measurements. Forces needed to stimulate the metatarsal lyriform vibration detector by deflecting the tarsus rise exponentially from ca. 240 μN/° at threshold to 3 mN/° at the upper natural limit. The equivalent relation is linear (1 to 2 mN/°) for a proprioceptive lyriform organ, stimulated by lateral displacement of the metatarsus. Thus the biologically most relevant difference regarding working range and amplitude resolution has a strong mechanical basis. Similarly, the physiological high pass characteristics of the vibration detector correlates with the visco-elasticity of a cuticular pad in front of the organ which transforms the stimulus on its way to the slits. Slit compression varies between 4.4 and 136 nm/mN depending on the slit within the array. doi:10.1016/j.cbpa.2007.01.258
A7.17 Arthropod flow sensing: When MEMS design learns from physical ecology
A7.19 A biomimetic IR sensor based on a mechanosensor
J. Casas, (University Tours, France) This talk will present the approach and the latest advances in the design of an MEMS air flow sensor within a large bionics EU project using cricket hairs as inspiration. In particular, I will present the boundary layer flows we measured around the cricket cerci (hairs bearing appendages) using PIV and the implemented MEMS artificial hairs. The first results concerning flow around single hairs observed using micro-PIV will also be presented, as well as the aerodynamical stimuli produced by hunting spiders and picked up by the prey's hairs. doi:10.1016/j.cbpa.2007.01.257
A7.18 Arthropod mechanoreceptors: From biology to engineering F. Barth, C. Schaber, (University of Vienna, Austria); B. Hössl, H. Böhm, F. Rammerstorfer, (Vienna University of Technology, Austria); S. Gorb, (Max Planck Institute for Metals Research, Germany) Arachnid slit sensilla monitor minute cuticular strains in the exoskeleton which are due to muscle activity, hemolymph pressure and substrate vibrations. Their highly refined micromechanical properties are modelled to establish a basis for the design of biomimetic force sensors. We report on finite element
H. Schmitz, A. Schmitz, (University of Bonn, Germany); M. Tewes, (Center of Advanced European Studies and Research, Bonn, Germany) Buprestid beetles of the genus Melanophila approach forest fires because their larvae can only develop in the wood of freshly burnt trees. For the detection of fires beetles are equipped with 2 thoracic infrared (IR) pit organs. Each IR organ houses about 70 IR sensilla located at the bottom of each pit. From the outside, a single IR sensillum can be recognized by a hemispherical dome with a diameter of about 12–15 μm. The dome is built by a thin cuticle representing the outer boundary of a spherical internal cavity. The cavity is almost completely filled out by a tiny cuticular sphere with a diameter of about 10 μm. The sphere is connected to the vertex of the cuticular dome by a small cuticular stalk. Most likely these receptors have evolved from hair mechanoreceptors (sensilla trichodea) of the lateral body wall. Compared to a hair mechanoreceptor, an IR sensillum shows the following special features: (i) the formation of a complex cuticular sphere instead of the bristle; the sphere consists of an outer exocuticular shell as well as of an inner porous mesocuticular part. (ii) The enclosure of the dendritic tip of the mechanosensitive neuron inside the sphere in a fluid-filled inner pressure chamber which is connected with a system of microcavities in the mesocuticular part. Hence we propose that an IR sensillum most probably acts as a microfluidic converter of infrared radiation into an increase in internal
S133
A7.13 Tensile water technology — An effort to learn from trees
artificial muscles will demonstrate how man and robots can gently work together in the future.
C. Toetzke, H. Tributsch, N. Szabo, (Hahn-Meitner-Institut Berlin, Germany)
doi:10.1016/j.cbpa.2007.01.254
2 layer was used to simulate the evaporative sites of leafs. During evaporation, the structural changes of the confined water have been observed by means of ATR-infrared spectroscopy. The shifting absorption spectra have been interpreted in terms of structural transitions towards greater water cluster possessing a higher degree of cross linking. The findings point to the formation of the tensile water inside the pores resulting from the evaporation process. Another experimental set up was used to simulate the water ascent in trees. A nanoporous evaporation body was mounted on top of a long glass capillary. After thorough cleaning the system was filled with water and the lower end of the capillary submerged into mercury. While evaporation took place from the nanopores mercury was pulled up inducing a pressure drop inside the capillary. The water was stressed well into the domain of negative pressure before cavitation occurred and the water column broke. This setup can be used to identify morphologic key factors for possible technical applications.
A7.15 Optic flow based autopilot: From insects to rotorcraft and back
doi:10.1016/j.cbpa.2007.01.253
A7.14 Bionics — Innovative structural solutions in fluiddynamics and robotics R. Bannasch, (Evologics Berlin, Germany) Looking at the functional anatomy of living organisms trough the eyes of an engineer one can discover a wealth of inspiring, evolutionary optimised and practically well proven structural solutions suitable to stimulate also a new concept for the development of modern high-tech constructions. The paper will give some examples to illustrate how nature makes use of elastic materials and self-adaptive structures in order to increase functional reliability and fault tolerance dramatically as well as to reduce weight, energy consumption and neuronal control in operation. The application of similar concepts to engineering leads to an approach recently characterized by terms like “intelligent embodiment” or “morphological intelligence”. Artificial covering feathers were successfully tested in aircrafts to prevent stall in crucial flight manoeuvres by blocking the reverse flow at the suction side of the wings at high angles of attack. The unusual self-adaptive behaviour of fish fins (Fin Ray Effect ®) leads to a new concept in adaptive wing profiles and facilitated the design of an artificial manta ray with a very “organic” swimming behaviour. Other useful applications of the Fin Ray Effect ® are e.g. a backrest self-adapting to the shape of the human body and a new type of grippers able to handle fragile objects with variable shapes. Finally, a life-sized humanoid robot with
N. Franceschini, F. Ruffier, J. Serres, (CNRS and University of the Mediterranean, France) When insects are flying forwards, the image of the ground sweeps backwards across their ventral viewfield, forming an ‘optic flow’, which depends on both the groundspeed and the height of flight. To explain how these animals manage to avoid the ground using this image motion cue, we suggest that insect navigation hinges on a visual feedback loop we have called the optic flow regulator, which controls the vertical lift. To test this idea, we built a micro-helicopter equipped with a fly-inspired optic flow sensor and an optic flow regulator. We showed that this fly-by-sight microrobot can perform exacting tasks such as take-off, level flight and landing. Our control scheme accounts for many hitherto unexplained findings published during the last 70 years on insects' visually guided performances, including the facts that honeybees descend under headwind conditions, land with a constant slope and drown when travelling over mirror-smooth water. Our control scheme explains how insects manage to fly safely without any of the instruments used onboard aircraft to measure the height of flight, the airspeed, the groundspeed, and the descent speed. An optic flow regulator could be easily implemented neurally. It is just as appropriate for insects (1) as it would be for aircraft (2,3). (1) Franceschini et al., Curr. Biol. (2007, in press). (2) Ruffier, F., Franceschini, Rob. Aust. Syst. Bot. 50, 177–194 (2005). (3) Franceschini et al., CNRS International Patent: PCT Nb 28 44 607 (2002). doi:10.1016/j.cbpa.2007.01.255
A7.16 Novel micro aircraft inspired by insect flight D. Lentink, N. Bradshaw, S.R. Jongerius, (Wageningen University, The Netherlands) A team of biologist and engineers of Wageningen University, Ruijsink Dynamic Engineering and Delft university of Technology has developed “Delfly”, a flapping micro air vehicle (MAV) inspired by Insect flight. Delfly has flexible saillike wings and as a result the wings deformation depends on both wing inertia and aero-elasticity. Flapping wings are able to generate lift based on delayed stall mechanisms. Delfly has this
S134
Abstracts / Comparative Biochemistry and Physiology, Part A 146 (2007) S129–S141
capability; it can flap its wings at angles of attack well beyond stall-without loss of lift, a phenomena utilized by insects. As a result Delfly can fly both fast and hover, recently it has even flown backwards. The aerodynamic optimization of Delfly is carried with a force balance and a total power-measurement set-up in a vacuum chamber. With this set-up we can optimize the thrust and lift generation with respect to total power. The vacuum chamber allows us to determine both the inertial and aerodynamic power contribution. The chamber also allows us to study wing deformation; is the deformation of the flexible wing dominated by inertial or aerodynamic force? To quantify wing deformation time-resolved we use high speed video. Finally we will elucidate our future plans for the development of NanoFly, a flapping NAV with a wing span of less than 2”. For its wing design we analyzed dragonfly wings using 3D microCT scans, image processing and the Finite Element Method. Based on this analysis we pre-designed miniature carbon fiber wings and a micro production process to fabricate aeroelastically tailored flapping wings inspired by insect flight. doi:10.1016/j.cbpa.2007.01.256
(FE) and interferometric (IF) analyses and on atomic force microscopy (AFM) of close parallel, lyriform slit arrays. FE analysis. Even minor morphological variations of slit arrangement affect slit interaction and thus stimulus transformation. The compressive slit face displacement D, which leads to nervous excitation, is mainly influenced by slit length l and load direction F whereas a slit's aspect ratio (20–100) is hardly relevant. At lateral distances between slits typical of lyriform organs (S = 0.03 l) their lateral shift ? considerably influences slit compression. White light IF, micro force measurements. Forces needed to stimulate the metatarsal lyriform vibration detector by deflecting the tarsus rise exponentially from ca. 240 μN/° at threshold to 3 mN/° at the upper natural limit. The equivalent relation is linear (1 to 2 mN/°) for a proprioceptive lyriform organ, stimulated by lateral displacement of the metatarsus. Thus the biologically most relevant difference regarding working range and amplitude resolution has a strong mechanical basis. Similarly, the physiological high pass characteristics of the vibration detector correlates with the visco-elasticity of a cuticular pad in front of the organ which transforms the stimulus on its way to the slits. Slit compression varies between 4.4 and 136 nm/mN depending on the slit within the array. doi:10.1016/j.cbpa.2007.01.258
A7.17 Arthropod flow sensing: When MEMS design learns from physical ecology
A7.19 A biomimetic IR sensor based on a mechanosensor
J. Casas, (University Tours, France) This talk will present the approach and the latest advances in the design of an MEMS air flow sensor within a large bionics EU project using cricket hairs as inspiration. In particular, I will present the boundary layer flows we measured around the cricket cerci (hairs bearing appendages) using PIV and the implemented MEMS artificial hairs. The first results concerning flow around single hairs observed using micro-PIV will also be presented, as well as the aerodynamical stimuli produced by hunting spiders and picked up by the prey's hairs. doi:10.1016/j.cbpa.2007.01.257
A7.18 Arthropod mechanoreceptors: From biology to engineering F. Barth, C. Schaber, (University of Vienna, Austria); B. Hössl, H. Böhm, F. Rammerstorfer, (Vienna University of Technology, Austria); S. Gorb, (Max Planck Institute for Metals Research, Germany) Arachnid slit sensilla monitor minute cuticular strains in the exoskeleton which are due to muscle activity, hemolymph pressure and substrate vibrations. Their highly refined micromechanical properties are modelled to establish a basis for the design of biomimetic force sensors. We report on finite element
H. Schmitz, A. Schmitz, (University of Bonn, Germany); M. Tewes, (Center of Advanced European Studies and Research, Bonn, Germany) Buprestid beetles of the genus Melanophila approach forest fires because their larvae can only develop in the wood of freshly burnt trees. For the detection of fires beetles are equipped with 2 thoracic infrared (IR) pit organs. Each IR organ houses about 70 IR sensilla located at the bottom of each pit. From the outside, a single IR sensillum can be recognized by a hemispherical dome with a diameter of about 12–15 μm. The dome is built by a thin cuticle representing the outer boundary of a spherical internal cavity. The cavity is almost completely filled out by a tiny cuticular sphere with a diameter of about 10 μm. The sphere is connected to the vertex of the cuticular dome by a small cuticular stalk. Most likely these receptors have evolved from hair mechanoreceptors (sensilla trichodea) of the lateral body wall. Compared to a hair mechanoreceptor, an IR sensillum shows the following special features: (i) the formation of a complex cuticular sphere instead of the bristle; the sphere consists of an outer exocuticular shell as well as of an inner porous mesocuticular part. (ii) The enclosure of the dendritic tip of the mechanosensitive neuron inside the sphere in a fluid-filled inner pressure chamber which is connected with a system of microcavities in the mesocuticular part. Hence we propose that an IR sensillum most probably acts as a microfluidic converter of infrared radiation into an increase in internal