In this paper, a fusion of the improved particle swarm algorithm and proportional–integral–derivative control algorithm in path tracking is investigated to improve the accuracy and robustness of path tracking of automated guided trolleys in complex environments. A robot operating system is introduced to provide a modular solution for the automated guided trolley system, which simplifies the integration of system components and provides a framework for system upgrading and expansion.

This paper presents a ring four-array rolling mechanism consisting of four anti-parallelogram mechanisms with revolute joints. The mechanism is connected by four anti-parallelograms in a looped configuration and has a not-totally-closed ring shape. The mechanism has planar and spherical patterns of locomotion: the planar pattern locomotion includes the parallelogram rolling gait and the anti-parallelogram tumbling gait and the spherical pattern locomotion includes the spherical rolling gait.