SHAO Qi1,2, LIU Hao1, YANG Zhenda1, WANG Hengzhi1, LI Hongyi1
1. State Key Laboratory of Robotics, Shenyang Institute of Automation, Chinese Academy of Sciences, Shenyang 110016, China;
2. University of Chinese Academy of Sciences, Beijing 100049, China
Facing the safety and feasibility problems of the existing active capsule robots, a legged capsule robot is proposed based on telescopic and translational mechanisms. The telescopic mechanism adopts the micro link structure, while the translational mechanism adopts the screw-nut structure. With the constraints of spatial location, speed and driving force, these two mechanisms are modeled and analyzed to optimize the dimensional parameters and motor operating parameters. After the optimization, the range of the telescopic speed is 16.8 mm/s~34.2 mm/s, the range of the telescopic force is 2.45N~0.44 N, and the range of the telescopic efficiency is 92.8%~34.0%. Meanwhile, the translational speed, the force and the efficiency remain constant basically, which are 50 mm/min, 4.20 N and 50% respectively. The length and the outer diameter of the driving unit in the capsule robot are 33mm and 16mm respectively. Finally, the performance of the legged capsule robot is tested in the porcine colon, and the result shows that it can realize the telescopic and translational locomotion efficiently and safely with the mean speed of 25 mm/min.
[1] Siegel R, DeSantis C, Jemal A. Colorectal cancer statistics[J]. CA: A Cancer Journal for Clinicians, 2014, 64(2): 104-117. [2] Iddan G, Meron G, Glukhovsky A, et al. Wireless capsule endoscopy[ J]. Nature, 2000, 405(6785): 417.[3] Carpi F, Kastelein N, Talcott M, et al. Magnetically controllable gastrointestinal steering of video capsules[J]. IEEE Transactions on Biomedical Engineering, 2011, 58(2): 231-234. [4] Swain P, Toor A, Volke F, et al. Remote magnetic manipulation of a wireless capsule endoscope in the esophagus and stomach of humans[J]. Gastrointestinal endoscopy, 2010, 71(7): 1290- 1293. [5] Rey J F, Ogata H, Hosoe N, et al. Blinded nonrandomized comparative study of gastric examination with a magnetically guided capsule endoscope and standard videoendoscope[J]. Gastrointestinal Endoscopy, 2012, 75(2): 373-381. [6] 张永顺,于宏海,阮晓燕,等.新型肠道胶囊式微型机器人的运动特性[J].机械工程学报,2009,45(8):18-23. Zhang Y S, Yu H H, Ruan X Y, et al. Kinematics characteristic of a new capsule-type micro robot in intestine[J]. Journal of Mechanical Engineering, 2009, 45(8): 18-23.[7] Yim S, Sitti M. Design and rolling locomotion of a magnetically actuated soft capsule endoscope[J]. IEEE Transactions on Robotics, 2012, 28(1): 183-194. [8] Simi M, Valdastri P, Quaglia C, et al. Design, fabrication, and testing of a capsule with hybrid locomotion for gastrointestinal tract exploration[J]. IEEE/ASME Transactions on Mechatronics, 2010, 15(2): 170-180. [9] Kim B, LeeMG, Lee Y P, et al. An earthworm-like micro robot using shape memory alloy actuator[J]. Sensors and Actuators A: Physical, 2006, 125(2): 429-437. [10] Lin W, Shi Y T, Jia Z W, et al. Design of a wireless anchoring and extending micro robot system for gastrointestinal tract[J]. The International Journal of Medical Robotics and Computer Assisted Surgery, 2013, 9(2): 167-179. [11] Kim Y T, Kim D E. Novel propelling mechanisms based on frictional interaction for endoscope robot[J]. Tribology Transactions, 2010, 53(2): 203-211. [12] Menciassi A, Stefanini C, Gorini S, et al. Legged locomotion in the gastrointestinal tract[C]//IEEE/RSJ International Conference on Intelligent Robots and Systems. Piscataway, USA: IEEE, 2004: 937-942.[13] Sliker L J, Kern M D, Schoen J A, et al. Surgical evaluation of a novel tethered robotic capsule endoscope using micro-patterned treads[J]. Surgical Endoscopy and Other Interventional Techniques, 2012, 26(10): 2862-2869. [14] Woo S, Kim T, Cho J. Stopping mechanism for capsule endoscope using electrical stimulus[J]. Medical and Biological Engineering and Computing, 2010, 48(1): 97-102. [15] Kim H M, Yang S, Kim J, et al. Active locomotion of a paddling-based capsule endoscope in an in vitro and in vivo experiment[J]. Gastrointestinal Endoscopy, 2010, 72(2): 381-387. [16] 林蔚,颜国正.驻留-伸缩式微型胃肠道机器人的力学模型[J].机器人,2012,34(5):553-558. Lin W, Yan G Z. Mechanical modeling of an anchoringextending gastrointestinal micro robot[J]. Robot, 2012, 34(5): 553-558.[17] Gorini S, Quirini M, Menciassi A, et al. A novel SMAbased actuator for a legged endoscopic capsule[C]//IEEE/RASEMBS International Conference on Biomedical Robotics and Biomechatronics. Piscataway, USA: IEEE, 2006: 443-449.[18] Quirini M, Menciassi A, Scapellato S, et al. Feasibility proof of a legged locomotion capsule for the GI tract[J]. Gastrointestinal Endoscopy, 2008, 67(7): 1153-1158. [19] Quirini M, Menciassi A, Scapellato S, et al. Design and fabrication of a motor legged capsule for the active exploration of the gastrointestinal tract[J]. IEEE/ASME Transactions on Mechatronics, 2008, 13(2): 169-179. [20] Valdastri P, Webster R J, Quaglia C, et al. A new mechanism for mesoscale legged locomotion in compliant tubular environments[J]. IEEE Transactions on Robotics, 2009, 25(5): 1047- 1057. [21] Dario P, Ciarletta P, Menciassi A, et al. Modeling and experimental validation of the locomotion of endoscopic robots in the colon[J]. International Journal of Robotics Research, 2004, 23(4/5): 549-556.[22] Zhang C, Liu H, Tan R, et al. Modeling of velocity-dependent frictional resistance of a capsule robot inside an intestine[J]. Tribology Letters, 2012, 47(2): 295-301. [23] Ciarletta P, Dario P, Tendick F, et al. Hyperelastic model of anisotropicber reinforcements within intestinal walls for applications in medical robotics[J]. International Journal of Robotics Research, 2009, 28(10): 1279-1288. [24] Carta R, Thone J, Puers R. A wireless power supply system for robotic capsular endoscopes[J]. Sensors and Actuators A: Physical, 2010, 162(2): 177-183.