In this article,in order to enhance the omnidirectional maneuverability of outdoor wheeled mobile robots,a mo-bile robot driven by a common wheel is proposed,which realizes the modes of four-wheel steering(4WS),oblique motion and spot turn,according to different power distribution and angle of leg rotation.A dual-mode hybrid controller is designed based on the oblique motion and 4WS modes.The oblique motion mode adopts multi-point pre-scanning fuzzy-compensation trajectory tracking control;the 4WS mode uses the incremental linear time-varying model predictive control(ILTV-MPC).The constraints required for the dual-mode hybrid controller are identified by experimenting the prototype's transverse and longitudinal tracking performance.The joint Simulink/CarSim simulation platform is used to verify that the controller is effective.The chassis of the mobile robot equipped with the hybrid controller has 0.18％difference in the root mean square error compared to the 4WS mode in terms of low curvature tracking,and the transverse swing angle and the transverse swing angular velocity remain constant.The re-sults show that the hybrid controller ensures the all-wheel steering robot's high accuracy in terms of low-curvature tracking while improving its transverse pendulum stability.
关键词
斜行模式/四轮转向模式/轨迹跟踪/多点预瞄/双模式混合控制
Key words
oblique motion mode/four-wheel steering mode/trajectory tracking/multi-point pre-scanning/dual-mode hy-brid control
维普
万方数据