Cooperative control of multiple magnetically controlled soft robots

Abstract

Multiple magnetically controlled soft robots are more efficient in terms of task execution. However, how to realize such multiple robots moving along the respective different paths is still a challenge since they are in one driving magnetic field. In order to deal with this problem, this paper proposes a cooperative control method by fusing their parallel cooperative motion (multiple robots moving simultaneously) and their independent cooperative motion (single robot moving). Yet, there are two strong couplings in the fusion of such two cooperative motions, which makes the control more difficult. Thus, an enumeration-based decoupling algorithm is developed for the first combined mode coupling, and the speed of each robot is planned for the second motion speed coupling. Then, a neural network-based controller is developed to achieve the respective speed control simultaneously of multiple robots, and the deviation limiting controller is constructed to compensate the deviation angle. Finally, through the actual experiments, it is verified that the proposed method realizes effectively the motion of two robots along different paths and the mean absolute error of speed is about 0.1091 mm/s and 0.2118 mm/s, while the mean absolute error of tracking is about 0.3369 mm and 0.4454 mm, respectively.