关键词: 给药胶囊, 倾角传感式磁检测, 磁场逆问题求解, 人工蜂群算法

Abstract: To realize an accurate releasing by a drug-delivery capsule in the gastrointestinal tract, a method of magnetic vector detection with angle sensing has been presented to track the capsule in real time; and a prototype of the tracking system has been developed. Based on the fundamentals of spatial distribution of magnetic vector fields, a nonlinear model of tracking is established. An improved artificial bee colony algorithm is studied to solve the magnetic inverse problem. In the improved algorithm, a chaos operator is used to generate an initial population and a sort selection is used to prevent premature convergence. To accelerate the convergence speed in the later stage, the Levenberg-Marquardt algorithm is combined with the artificial bee colony algorithm. The algorithm simulation experiment shows that the average number of iterations is 215. The average position error and standard deviation of x, y and z are 0.002 2 m±0.000 12 m, 0.001 9 m±0.000 084 m, and 0.002 0 m±0.000 078 m, respectively. The nonlinear optimization problem of tracking can be rapidly and accurately solved.

Key words: drug delivery capsules, magnetic vector detection with angle sensing, solving of a magnetic inverse problem, an artificial bee colony algorithm