Finding an optimal trajectory from an initial point to a final point through closely packed obstacles, and controlling a Hilare robot through this trajectory, are challenging tasks. To serve this purpose, path planner...Finding an optimal trajectory from an initial point to a final point through closely packed obstacles, and controlling a Hilare robot through this trajectory, are challenging tasks. To serve this purpose, path planners and trajectory-tracking controllers are usually included in a control loop. This paper highlights the implementation of a trajectory-tracking controller on a stepper motor-driven Hilare robot, with a trajectory that is described as a set of waypoints. The controller was designed to handle discrete waypoints with directional discontinuity and to consider different constraints on the actuator velocity. The control parameters were tuned with the help of multi-objective particle swarm optimization to minimize the average cross-track error and average linear velocity error of the mobile robot when tracking a predefined trajectory. Experiments were conducted to control the mobile robot from a start position to a destination position along a trajectory described by the waypoints. Experimental results for tracking the trajectory generated by a path planner and the trajectory specified by a user are also demonstrated. Experiments conducted on the mobile robot validate the effectiveness of the proposed strategy for tracking different types of trajectories.展开更多
According to the principle of bionics, a prototype of the earthworm-like micro robot was developed and manufactured for entering the small tube. Based on the process of the action and mechanics analysis, the controlle...According to the principle of bionics, a prototype of the earthworm-like micro robot was developed and manufactured for entering the small tube. Based on the process of the action and mechanics analysis, the controller was designed. This micro robot with 6mm diameter was driven directly by three electromagnetic linear drivers. Mobile cells were joined with two degree-of-freedom joint and the whole body was flexible and soft. The driving force reached 10.8g in normal working condition. The direction of movement and the angle of imaging can be controlled by the shape memory alloy （SMA）. The driving force, velocity and movement of micro robot in flexural tube were tested through experiments, which indicated that the driving force was in proportion to the range of frequency, and the micro robot could current, and the velocity reached a maximum in certain move in the thin tube flexibly.展开更多
文摘Finding an optimal trajectory from an initial point to a final point through closely packed obstacles, and controlling a Hilare robot through this trajectory, are challenging tasks. To serve this purpose, path planners and trajectory-tracking controllers are usually included in a control loop. This paper highlights the implementation of a trajectory-tracking controller on a stepper motor-driven Hilare robot, with a trajectory that is described as a set of waypoints. The controller was designed to handle discrete waypoints with directional discontinuity and to consider different constraints on the actuator velocity. The control parameters were tuned with the help of multi-objective particle swarm optimization to minimize the average cross-track error and average linear velocity error of the mobile robot when tracking a predefined trajectory. Experiments were conducted to control the mobile robot from a start position to a destination position along a trajectory described by the waypoints. Experimental results for tracking the trajectory generated by a path planner and the trajectory specified by a user are also demonstrated. Experiments conducted on the mobile robot validate the effectiveness of the proposed strategy for tracking different types of trajectories.
文摘According to the principle of bionics, a prototype of the earthworm-like micro robot was developed and manufactured for entering the small tube. Based on the process of the action and mechanics analysis, the controller was designed. This micro robot with 6mm diameter was driven directly by three electromagnetic linear drivers. Mobile cells were joined with two degree-of-freedom joint and the whole body was flexible and soft. The driving force reached 10.8g in normal working condition. The direction of movement and the angle of imaging can be controlled by the shape memory alloy （SMA）. The driving force, velocity and movement of micro robot in flexural tube were tested through experiments, which indicated that the driving force was in proportion to the range of frequency, and the micro robot could current, and the velocity reached a maximum in certain move in the thin tube flexibly.
