Thermal analysis of the “internal force-static friction” capsule robot

Currently, various active capsule endoscopes have been developed to overcome the disadvantages of passive locomotion. Most of them are driven by electric motor or other actuators that need more energy, which will raise temperature and result in potential dangers. The high temperature will not only hurt the intestinal wall and tissue, but also affect the performance of electronic device embedded. In this paper, we focus on the thermal analysis of a novel active capsule endoscope called “internal force-static friction capsule robot (capsubot)”. The thermal distribution of the capsubot is calculated with the Finite Element Analysis (FEA) tools and the results are verified by experiments. Medical data on allowable temperature is referred and 43°C is selected as the thermal threshold of biological safety for the small intestine. The results show that the temperature of the whole capsubot is below 41°C, thus the capsubot is safe for human and the components embedded can work normally.

[1]  E. Yoon,et al.  Active locomotion of a paddling-based capsule endoscope in an in vitro and in vivo experiment (with videos). , 2010, Gastrointestinal endoscopy.

[2]  Hongyi Li,et al.  A linear driving mechanism applied to capsule robots , 2009, 2009 International Conference on Networking, Sensing and Control.

[3]  Bo Zhang,et al.  Thermal Safety Analysis of Capsule Endoscope , 2006, 2006 7th International Conference on Electronic Packaging Technology.

[4]  Yongshun Zhang,et al.  A Variable-Diameter Capsule Robot Based on Multiple Wedge Effects , 2011, IEEE/ASME Transactions on Mechatronics.

[5]  Hongyi Li,et al.  A design of the electromagnetic driver for the “internal force-static friction” capsubot , 2009, 2009 IEEE/RSJ International Conference on Intelligent Robots and Systems.

[6]  Byungkyu Kim,et al.  An earthworm-like micro robot using shape memory alloy actuator , 2006 .

[7]  P. Dario,et al.  Design and Fabrication of a Motor Legged Capsule for the Active Exploration of the Gastrointestinal Tract , 2008, IEEE/ASME Transactions on Mechatronics.

[8]  Dieter Haemmerich,et al.  In vitro measurements of temperature-dependent specific heat of liver tissue. , 2006, Medical engineering & physics.