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Force Measurement of Blood Vessel Gripping by Hydraulic-driven Forceps
Available online at www.sciencedirect.com
ScienceDirect Procedia CIRP 65 (2017) 84 – 87
3rd CIRP Conference on BioManufacturing
Force measurement of blood vessel gripping by hydraulic-driven forceps Tohru Sasakia, Masao Hebisawaa, Yasuyuki Mitoa, Kuniaki Dohdab and Satoshi Kurodac * a
Department of Mechanical and Intellectual Sys tems Engineering, University of Toyama, Gofuku 3190, Toyama-shi, Toyama 930-8555, Japan b Department of Mechanical Engineering, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208, USA c Department of Neurosurgery, University of Toyama, Sugitani 2630, Toyama-shi, Toyama 930-0194, Japan
* Corresponding author. Tel.: +81-76-445-6801; fax: +81-76-445-6801. E-mail address: [email protected]
Abstract Surgical manipulators are widely used for laparoscopic surgery. They have mainly been chosen for use in supporting human operations and in robot systems like the da Vinci surgical system. These manipulator systems are suitable for careful work, but they have a few problems. One is that the manipulators are not equipped with haptic sensing functions. Therefore, the operator must know advanced techniques for visually detecting the physical contact state during surgical operation. Such haptic sensing functions thus need to be incorporated into surgical manipulators. We have developed hydraulic-driven forceps with a micro bearing and a bellows tube that can convey haptic sense to the operator. For accurate surgicaloperation, the operator of the surgical manipulator must be able to feel the characteristics of the blood vessel and the organ. For example, it is necessary to feel the pulsation of the blood. In addition, the operator must be able to notice any potential rupture of a blood vessel to prevent a medical accident. We tested our system to determine if it could detect characteristic differences and changes of the blood vessel. This report describes the results and discusses the effectiveness of our system. © Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license ©2016 2017The The Authors. Published by Elsevier B.V. (http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer-review under responsibility of the scientific committee of the 3rd CIRP Conference on BioManufacturing 2017. Peer-review under responsibility of the scientific committee of the 3rd CIRP Conference on BioManufacturing 2017 Keywords: Hydraulic-driven, forceps, force feedback, surgical manipulator
1. Introduction Surgical manipulators have recently been in widespread use in supporting human operations [1-5]. When the manipulator is not equipped with haptic sensing functions, the operator must possess advanced techniques for visually detecting the physical contact state during surgical operations. Recently, many researchers study about the solution to this problem. For instance, a force sensing probe to be used with the da Vinci tools [6,7] and bilateral control system for force feedback [810] was developed. Hydraulic-driven mechanisms have recently been used in the medical field [11] and the masterslave system using the air was proposed [12-13]. We have developed a hydraulic-driven forceps that can measure the holding force. In this study, we checked whether our system could detect characteristic differences and changes of the blood vessel. A forceps holds the blood vessel model, moves around a little while holding it, and then releases it. Models of the held blood vessel were made up of silicon rubber 0.3 mm, 1 mm, and
2 mm in diameter. The forceps was able to detect differences in size and was also able to detect the difference between a filled blood vessel model and a hollow one. The forceps was also able to measure pulsation of the blood vessel clearly. All results of experiments demonstrate the effectiveness of our system. 2. Mechanism of forceps The drive system for the forceps is shown in Fig. 1(a). The system consist of micro forceps and water supply machine. The principle of the hydraulic driven forceps is shown in Fig. 1(b). Forceps consists of a bellows tube moving with water. Because a syringe is used to both supply and extract water, the bellows tube has to be able to both expand and contract. This is what enables the forceps to hold something [14]. The amount of liquid to supply to the bellows tube by moving the linear actuator is controlled and the operator is able to open and close the forceps precisely. The force sensor is fixed between the plunger and the actuator rod of the linear actuator. Since the
2212-8271 © 2016 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer-review under responsibility of the scientific committee of the 3rd CIRP Conference on BioManufacturing 2017 doi:10.1016/j.procir.2017.04.002
85
Tohru Sasaki et al. / Procedia CIRP 65 (2017) 84 – 87
force sensor measures the amount of force acting on the plunger, the internal pressure inside the syringe can be obtained [15]. Measured internal pressure is compared with the displacement-fluid pressure model of the forceps, and the difference in quantity is measured as the holding force. This system can measure the small forces acting on the tips of the forceps by using Pascal’s principle [16], [17].
3. Experiment of blood vessel gripping 3.1. Sizes of object The experimentally produced forceps were also used in a force measurement experiment. Figure 2 shows a photograph of a blood vessel model made up of silicon rubber 0.3 mm, 1 mm, and 2 mm in diameter. Figure 3 shows the enlarged forceps to hold the blood vessel model. The linear actuator moved the syringe in accordance with a position command issued from a personal computer and supplied water to the bellows tube of the forceps to 0.05 ml by
Forceps
(a)
Hydraulic driven forceps mechanism.
1mm
Blood vessel model
Fig. 3. Forceps holding the blood vessel model.
1.0 0.9 0.8
㻌䃥1.0mm 㻌䃥2.0mm 㻌䃥0.3mm
Holding force [N]
Principle of hydraulic driven forceps. Fig. 1. Forceps mechanics.
1.01mm
2.04mm
0.7
(b)
0.22mm
0.6 0.5 0.4 0.3
1mm㻌
0.2 0.1 0.0
φ2mm㻌 φ1mm㻌
φ0.3mm㻌
0.0
0.5
1.0 1.5 2.0 Closing amount [mm]
2.5
Fig. 4. Measurement force holding object of different sizes. Fig. 2. Blood vessel models of different size.
2.8
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Tohru Sasaki et al. / Procedia CIRP 65 (2017) 84 – 87
0.2μⅼ. The forceps holds the blood vessel model, moves around a little while holding it, and then releases it. Figure 4 shows the change in the holding force, which was calculated from internal pressure on the basis of the rotary angle of the forceps. Closing amount measured with an image processing is linear displacement between the tip of the rotational part of the forceps and the tip of the stationary part of the forceps. It is considered to be the deformation of the blood vessel model. The holding force increased as the diameter of the blood vessel model increased. The estimated diameter were 2.04 mm, 1.01 mm and 0.22 mm. Because holding force is small with the blood vessel model that a diameter is the smallest, detected pressure is small. It is thought that the error of estimate occurred by the electric noise. This result shows that we can determine the size of the blood vessel from the difference of the measured holding force.
3.3. Change in characteristic of object For accurate work on a blood vessel, the operator of a surgical manipulator should be able to feel the pulsation of the blood and notice if the blood vessel ruptures so as to prevent a medical accident. Figure 6 shows a photograph of the experimental device that lets a blood vessel pulsate. Blood vessel models were made up of silicon rubber 1 mm in diameter. One side of the blood vessel leads to a pump and water drains from the other. A pulsation is given at 5-second intervals for a total of four in 20 seconds. The blood vessel is given continuous pulsation for the next 15 seconds. The blood vessel is then given long pulsation for the next five seconds. The linear actuator supplied water to the bellows tube of the forceps from 0.015 ml to up to 0.15 ml a forceps held the blood vessel model.
3.2. Filled vessel and hollow vessel The force holding the hollow blood vessel should be different from the force holding the filled blood vessel. 20 μL of water was injected with a syringe into one blood vessel model, 20 μL of washing paste was injected into another blood vessel model, and a final blood vessel model was injected with nothing. All blood vessel models were made up of 1 mm diameter silicon rubber. Both ends of the blood vessel models were closed. The linear actuator supplied water to the bellows tube of the forceps to 0.05 ml by 0.2μⅼ. Figure 5 shows the change in the holding force. Because all the blood vessel models were 1 mm diameter, all the measured holding forces became largest at around 0.026 ml. The holding force of the filled blood vessel model was clearly different from that of the hollow one. There was no difference between the model filled with water and that with washing paste.
Injection syringe
0.8
Holding force [N]
0.6
㻌air 㻌water 㻌paste
0.4
Forceps
0.2
0.0 Blood vessel model
0.00
0.01
0.02
0.03
0.04
0.05
Quantity of flowing medium [ml]
5 mm Fig. 5. Measurement force holding empty, filled with water, and filled with washing paste object.
Tohru Sasaki et al. / Procedia CIRP 65 (2017) 84 – 87 Fig. 6. Experimental method.
References [1]
0.25 5 sec.
0.20
Long pulsation
[2]
Sensing force㻌㻌[N]
0.15 0.10
[3]
0.05 [4]
0.00 -0.05
[5]
-0.10 A pulasation is given at 5-second.
-0.15 -0.20 -0.25
0
5
10
15
[6]
Continuous pulsation 20
25
30
35
40
45
50
[7]
Time [s] [8] Fig. 7. Measurement force with various pulsations. [9]
The internal pressure was measured every 0.015 seconds. Figure 7 shows the change in the holding force. The measurement value expresses the pulsation of the blood vessel clearly.
[10]
[11]
4. Conclusion [12]
The hydraulic-driven forceps we proposed for use with surgical manipulators was able to detect characteristic differences and changes of a blood vessel. The proposed forceps was able to detect blood vessel models of three different sizes (0.3 mm, 1 mm, and 2 mm). In addition, the forceps was able to detect the difference between a filled blood vessel model and a hollow one. The forceps was not able to detect difference in viscosity, although it was able to measure the pulsation of the blood vessel clearly.
[13]
[14]
[15] [16]
Acknowledgements This work was supported by JSPS KAKENHI Grant Number 15K05891.
[17]
Gettman TM, Blute LM, Chow KG, Neururer R, Bartsch G, Peschel R. Robotic-assisted laparoscopic partial nephrectomy : Technique and initial clinical experience with DaVinci robotic system. Urology 2004;64(5):914-8. Yamashita H, Kim D, Hata N, Dohi T. Multi-slider linkage mechanism for endscopic forceps manipulator. Conference on intelligent robots and system 2003;2577-82 . Hongo K, Goto T, Kakizawa Y, Koyama J. Microsurgery-assisting robotics (NeuRobot) : Current status and future perspective. Japanese journal of neurosurgery 2011;20(4):270-4. Kobatashi E, Miyamoto S, Ohyama K. Development of naviot for minimally invasive surgery. Journal of robotics society of Japan 2005;23(2):168-71. Fujie M, Umezu M, Iseki H. Development of a multi-DOF brain retract manipulator for minimally invasive surgery : Third report -Development of a total model for clinical application. Journal of Japan society of computer aided surgery 2002;4(3):255-6. McKinley S, Garg A, Kapadia R, Sen S, Murali A, Nichols K, Lim S, Patil S, Abbeel P, Okamura AM, Goldberg K. A Disposable haptic palpation probe for locating subcutaneous blood vessels in robotassisted minimally invasive surgery. IEEE international conference on automation science and engineering 2015;1151-8. Garg A, Sen S, Kapadia R, Jen Y, McKinley S, Miller L, Goldberg K. Tumor localization using automated palpation with gaussian process adaptive sampling. IEEE international conference on automation science and engineering (CASE) 2016;194-200. Hannaford B. A design framework for teleoperators with kinesthetic feedback. IEEE transactions on robotics and automation 1989;5(4):42634. Lawrence DA. Stability and transparency in bilateral teleoperation. IEEE transactions on robotics and automation 1993;9(5):624-37. Iida W, Ohnishi K. Reproducibility and operationality in bilateral teleoperation. Proceedings of 8th IEEE international workshop on advanced motion control 2004;217-22. Ikuta K, Ichikawa H, Suzuki K, Matsuda Y, Yajima D. Study on hydraulically driven active catheter for safe operation. Transactions of the Japan society of mechanical engineers series C 2010;76(766): 1553– 9. Noritsugu T, Takaiwa M. Robust positioning control of pneumatic servo system with pressure control loop. Proceedings of IEEE ICRA 1995; 2613-8. Tadano K, Kawashima K. Development of a master–slave system with force-sensing abilities using pneumatic actuators for laparoscopic surgery. Advanced robotics 2012; 24(12):1763-83. Sasaki T, Mito Y, Kyosei Y, Jindai M. Improving accuracy of hydraulicdriven forceps. Proceedings of the 16th international conference of the European society for precision engineering and nanotechnology 2016; p. 2.07. Sasaki T, Kokubo K, Sakai H. Hydraulically driven joint for a force feedback manipulator, Precision engineering 2017;47:445–51. Hebisawa M, Mito Y, Sasaki T, Dohada K. Development of force sensor using micro hydraulic-drive mechanism. Proceedings of the Japan society for precision engineering semestrial meeting spring conference 2016;873–4. Hebisawa M, Sasaki T, Dohda K, Mito Y, Jindai M, Ota S. Development of hydraulic-drive force sensor using micro cylinder. Proceedings of world congress on micro and nano manufacturing 2017;165–8.
87
ScienceDirect Procedia CIRP 65 (2017) 84 – 87
3rd CIRP Conference on BioManufacturing
Force measurement of blood vessel gripping by hydraulic-driven forceps Tohru Sasakia, Masao Hebisawaa, Yasuyuki Mitoa, Kuniaki Dohdab and Satoshi Kurodac * a
Department of Mechanical and Intellectual Sys tems Engineering, University of Toyama, Gofuku 3190, Toyama-shi, Toyama 930-8555, Japan b Department of Mechanical Engineering, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208, USA c Department of Neurosurgery, University of Toyama, Sugitani 2630, Toyama-shi, Toyama 930-0194, Japan
* Corresponding author. Tel.: +81-76-445-6801; fax: +81-76-445-6801. E-mail address: [email protected]
Abstract Surgical manipulators are widely used for laparoscopic surgery. They have mainly been chosen for use in supporting human operations and in robot systems like the da Vinci surgical system. These manipulator systems are suitable for careful work, but they have a few problems. One is that the manipulators are not equipped with haptic sensing functions. Therefore, the operator must know advanced techniques for visually detecting the physical contact state during surgical operation. Such haptic sensing functions thus need to be incorporated into surgical manipulators. We have developed hydraulic-driven forceps with a micro bearing and a bellows tube that can convey haptic sense to the operator. For accurate surgicaloperation, the operator of the surgical manipulator must be able to feel the characteristics of the blood vessel and the organ. For example, it is necessary to feel the pulsation of the blood. In addition, the operator must be able to notice any potential rupture of a blood vessel to prevent a medical accident. We tested our system to determine if it could detect characteristic differences and changes of the blood vessel. This report describes the results and discusses the effectiveness of our system. © Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license ©2016 2017The The Authors. Published by Elsevier B.V. (http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer-review under responsibility of the scientific committee of the 3rd CIRP Conference on BioManufacturing 2017. Peer-review under responsibility of the scientific committee of the 3rd CIRP Conference on BioManufacturing 2017 Keywords: Hydraulic-driven, forceps, force feedback, surgical manipulator
1. Introduction Surgical manipulators have recently been in widespread use in supporting human operations [1-5]. When the manipulator is not equipped with haptic sensing functions, the operator must possess advanced techniques for visually detecting the physical contact state during surgical operations. Recently, many researchers study about the solution to this problem. For instance, a force sensing probe to be used with the da Vinci tools [6,7] and bilateral control system for force feedback [810] was developed. Hydraulic-driven mechanisms have recently been used in the medical field [11] and the masterslave system using the air was proposed [12-13]. We have developed a hydraulic-driven forceps that can measure the holding force. In this study, we checked whether our system could detect characteristic differences and changes of the blood vessel. A forceps holds the blood vessel model, moves around a little while holding it, and then releases it. Models of the held blood vessel were made up of silicon rubber 0.3 mm, 1 mm, and
2 mm in diameter. The forceps was able to detect differences in size and was also able to detect the difference between a filled blood vessel model and a hollow one. The forceps was also able to measure pulsation of the blood vessel clearly. All results of experiments demonstrate the effectiveness of our system. 2. Mechanism of forceps The drive system for the forceps is shown in Fig. 1(a). The system consist of micro forceps and water supply machine. The principle of the hydraulic driven forceps is shown in Fig. 1(b). Forceps consists of a bellows tube moving with water. Because a syringe is used to both supply and extract water, the bellows tube has to be able to both expand and contract. This is what enables the forceps to hold something [14]. The amount of liquid to supply to the bellows tube by moving the linear actuator is controlled and the operator is able to open and close the forceps precisely. The force sensor is fixed between the plunger and the actuator rod of the linear actuator. Since the
2212-8271 © 2016 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer-review under responsibility of the scientific committee of the 3rd CIRP Conference on BioManufacturing 2017 doi:10.1016/j.procir.2017.04.002
85
Tohru Sasaki et al. / Procedia CIRP 65 (2017) 84 – 87
force sensor measures the amount of force acting on the plunger, the internal pressure inside the syringe can be obtained [15]. Measured internal pressure is compared with the displacement-fluid pressure model of the forceps, and the difference in quantity is measured as the holding force. This system can measure the small forces acting on the tips of the forceps by using Pascal’s principle [16], [17].
3. Experiment of blood vessel gripping 3.1. Sizes of object The experimentally produced forceps were also used in a force measurement experiment. Figure 2 shows a photograph of a blood vessel model made up of silicon rubber 0.3 mm, 1 mm, and 2 mm in diameter. Figure 3 shows the enlarged forceps to hold the blood vessel model. The linear actuator moved the syringe in accordance with a position command issued from a personal computer and supplied water to the bellows tube of the forceps to 0.05 ml by
Forceps
(a)
Hydraulic driven forceps mechanism.
1mm
Blood vessel model
Fig. 3. Forceps holding the blood vessel model.
1.0 0.9 0.8
㻌䃥1.0mm 㻌䃥2.0mm 㻌䃥0.3mm
Holding force [N]
Principle of hydraulic driven forceps. Fig. 1. Forceps mechanics.
1.01mm
2.04mm
0.7
(b)
0.22mm
0.6 0.5 0.4 0.3
1mm㻌
0.2 0.1 0.0
φ2mm㻌 φ1mm㻌
φ0.3mm㻌
0.0
0.5
1.0 1.5 2.0 Closing amount [mm]
2.5
Fig. 4. Measurement force holding object of different sizes. Fig. 2. Blood vessel models of different size.
2.8
86
Tohru Sasaki et al. / Procedia CIRP 65 (2017) 84 – 87
0.2μⅼ. The forceps holds the blood vessel model, moves around a little while holding it, and then releases it. Figure 4 shows the change in the holding force, which was calculated from internal pressure on the basis of the rotary angle of the forceps. Closing amount measured with an image processing is linear displacement between the tip of the rotational part of the forceps and the tip of the stationary part of the forceps. It is considered to be the deformation of the blood vessel model. The holding force increased as the diameter of the blood vessel model increased. The estimated diameter were 2.04 mm, 1.01 mm and 0.22 mm. Because holding force is small with the blood vessel model that a diameter is the smallest, detected pressure is small. It is thought that the error of estimate occurred by the electric noise. This result shows that we can determine the size of the blood vessel from the difference of the measured holding force.
3.3. Change in characteristic of object For accurate work on a blood vessel, the operator of a surgical manipulator should be able to feel the pulsation of the blood and notice if the blood vessel ruptures so as to prevent a medical accident. Figure 6 shows a photograph of the experimental device that lets a blood vessel pulsate. Blood vessel models were made up of silicon rubber 1 mm in diameter. One side of the blood vessel leads to a pump and water drains from the other. A pulsation is given at 5-second intervals for a total of four in 20 seconds. The blood vessel is given continuous pulsation for the next 15 seconds. The blood vessel is then given long pulsation for the next five seconds. The linear actuator supplied water to the bellows tube of the forceps from 0.015 ml to up to 0.15 ml a forceps held the blood vessel model.
3.2. Filled vessel and hollow vessel The force holding the hollow blood vessel should be different from the force holding the filled blood vessel. 20 μL of water was injected with a syringe into one blood vessel model, 20 μL of washing paste was injected into another blood vessel model, and a final blood vessel model was injected with nothing. All blood vessel models were made up of 1 mm diameter silicon rubber. Both ends of the blood vessel models were closed. The linear actuator supplied water to the bellows tube of the forceps to 0.05 ml by 0.2μⅼ. Figure 5 shows the change in the holding force. Because all the blood vessel models were 1 mm diameter, all the measured holding forces became largest at around 0.026 ml. The holding force of the filled blood vessel model was clearly different from that of the hollow one. There was no difference between the model filled with water and that with washing paste.
Injection syringe
0.8
Holding force [N]
0.6
㻌air 㻌water 㻌paste
0.4
Forceps
0.2
0.0 Blood vessel model
0.00
0.01
0.02
0.03
0.04
0.05
Quantity of flowing medium [ml]
5 mm Fig. 5. Measurement force holding empty, filled with water, and filled with washing paste object.
Tohru Sasaki et al. / Procedia CIRP 65 (2017) 84 – 87 Fig. 6. Experimental method.
References [1]
0.25 5 sec.
0.20
Long pulsation
[2]
Sensing force㻌㻌[N]
0.15 0.10
[3]
0.05 [4]
0.00 -0.05
[5]
-0.10 A pulasation is given at 5-second.
-0.15 -0.20 -0.25
0
5
10
15
[6]
Continuous pulsation 20
25
30
35
40
45
50
[7]
Time [s] [8] Fig. 7. Measurement force with various pulsations. [9]
The internal pressure was measured every 0.015 seconds. Figure 7 shows the change in the holding force. The measurement value expresses the pulsation of the blood vessel clearly.
[10]
[11]
4. Conclusion [12]
The hydraulic-driven forceps we proposed for use with surgical manipulators was able to detect characteristic differences and changes of a blood vessel. The proposed forceps was able to detect blood vessel models of three different sizes (0.3 mm, 1 mm, and 2 mm). In addition, the forceps was able to detect the difference between a filled blood vessel model and a hollow one. The forceps was not able to detect difference in viscosity, although it was able to measure the pulsation of the blood vessel clearly.
[13]
[14]
[15] [16]
Acknowledgements This work was supported by JSPS KAKENHI Grant Number 15K05891.
[17]
Gettman TM, Blute LM, Chow KG, Neururer R, Bartsch G, Peschel R. Robotic-assisted laparoscopic partial nephrectomy : Technique and initial clinical experience with DaVinci robotic system. Urology 2004;64(5):914-8. Yamashita H, Kim D, Hata N, Dohi T. Multi-slider linkage mechanism for endscopic forceps manipulator. Conference on intelligent robots and system 2003;2577-82 . Hongo K, Goto T, Kakizawa Y, Koyama J. Microsurgery-assisting robotics (NeuRobot) : Current status and future perspective. Japanese journal of neurosurgery 2011;20(4):270-4. Kobatashi E, Miyamoto S, Ohyama K. Development of naviot for minimally invasive surgery. Journal of robotics society of Japan 2005;23(2):168-71. Fujie M, Umezu M, Iseki H. Development of a multi-DOF brain retract manipulator for minimally invasive surgery : Third report -Development of a total model for clinical application. Journal of Japan society of computer aided surgery 2002;4(3):255-6. McKinley S, Garg A, Kapadia R, Sen S, Murali A, Nichols K, Lim S, Patil S, Abbeel P, Okamura AM, Goldberg K. A Disposable haptic palpation probe for locating subcutaneous blood vessels in robotassisted minimally invasive surgery. IEEE international conference on automation science and engineering 2015;1151-8. Garg A, Sen S, Kapadia R, Jen Y, McKinley S, Miller L, Goldberg K. Tumor localization using automated palpation with gaussian process adaptive sampling. IEEE international conference on automation science and engineering (CASE) 2016;194-200. Hannaford B. A design framework for teleoperators with kinesthetic feedback. IEEE transactions on robotics and automation 1989;5(4):42634. Lawrence DA. Stability and transparency in bilateral teleoperation. IEEE transactions on robotics and automation 1993;9(5):624-37. Iida W, Ohnishi K. Reproducibility and operationality in bilateral teleoperation. Proceedings of 8th IEEE international workshop on advanced motion control 2004;217-22. Ikuta K, Ichikawa H, Suzuki K, Matsuda Y, Yajima D. Study on hydraulically driven active catheter for safe operation. Transactions of the Japan society of mechanical engineers series C 2010;76(766): 1553– 9. Noritsugu T, Takaiwa M. Robust positioning control of pneumatic servo system with pressure control loop. Proceedings of IEEE ICRA 1995; 2613-8. Tadano K, Kawashima K. Development of a master–slave system with force-sensing abilities using pneumatic actuators for laparoscopic surgery. Advanced robotics 2012; 24(12):1763-83. Sasaki T, Mito Y, Kyosei Y, Jindai M. Improving accuracy of hydraulicdriven forceps. Proceedings of the 16th international conference of the European society for precision engineering and nanotechnology 2016; p. 2.07. Sasaki T, Kokubo K, Sakai H. Hydraulically driven joint for a force feedback manipulator, Precision engineering 2017;47:445–51. Hebisawa M, Mito Y, Sasaki T, Dohada K. Development of force sensor using micro hydraulic-drive mechanism. Proceedings of the Japan society for precision engineering semestrial meeting spring conference 2016;873–4. Hebisawa M, Sasaki T, Dohda K, Mito Y, Jindai M, Ota S. Development of hydraulic-drive force sensor using micro cylinder. Proceedings of world congress on micro and nano manufacturing 2017;165–8.
87