Control strategy for multiple capsule robots in intestine

Abstract

Based on the critical gap phenomenon of the intestinal capsule robot, a variable-diameter capsule robot with radial gap self-compensation is developed in this paper. With the functional variation principle, a fluid dynamic pressure model satisfying the boundary conditions of the outer surface of capsule robot with screw blades is derived. The critical gap phenomenon is studied theoretically and experimentally based on the end effect and the dynamic balance characteristics of the fluid on the surface of capsule robot. The concept of start-up rotation speed is defined, the relationship between the start-up rotation speed and the spiral parameters of capsule robot is investigated. The strategy for implementing drive and control on several capsule robots under the same rotational magnetic field is proposed, and by defining the start-up curves of several capsule robots with the similar motion regulation as the objective functions, genetic algorithm is employed to optimize the spiral parameters of several capsule robots. Experiments have shown that the proposed drive and control strategy for several capsule robots can be implemented effectively. It has a good prospect of application inside intestine to realize the drive and control on several capsule robots for different medical purposes.