Thermal Safety Analysis of Capsule Endoscope

Capsule endoscope is a micro medical device used to examine and treat gastrointestinal diseases. The development of multiple-functions such as imaging, signal sensing and movement control may require higher power consumption. The heat generated by high power consumption may cause damage to the cells of gastrointestinal canal. As there is little information on thermal safety analysis of capsule endoscope, this paper offers a beneficial try on analyzing the upper safe power limit of capsule endoscope. A model is established to simulate a capsule endoscope in small intestinal canal. The modeling considers the extreme situation which would cause the largest rise of temperature so as to ensure the safety in most other normal situations. The highest temperature point at the surface of capsule endoscope is referred to as the reference temperature Tm. With FEA tools, the temperature distribution around the capsule endoscope and Tm in the intestinal canal are calculated with different power levels, different emergency time and different outer boundary conditions. With Tm< 43 degC, the safe power limit is decided. This result provides references in the expansion of functions to ensure thermal safety. In addition, the heat flux distribution on the surface of capsule endoscope is analyzed. It demonstrates that when heat is evenly emitted from the entire surface, Tm is the lowest, and thus decreases the thermal danger