A composite sliding mode controller with extended disturbance observer for 4WSS agricultural robots in unstructured farmlands

Yafei Zhang, Yue Shen, Hui Liu, Siwei He, Zohaib Khan

Abstract: Highlights•The offset model from the improved kinematic model of the 4WSS is employed in design.•A higher-order disturbance observer is developed to handle disturbances.•A modified sliding mode surface with disturbance estimation ensures controller stability.•The path offset and heading offset in the paddy field tests are 0.0560 m, 1.2057°.