Gait Planning And Control Of Underactuated Planar Biped Robot Based On Flexible Joint

Biped walking is one of the most important movement modes of legged robots.Fast and stable walking ability is of great significance to the application of robots.The online planning method based on the ZMP criterion has been widely used in the motion control of biped robots.Underactuated biped walking is one of the important research directions of biped walking.It is different from the biped walking methods based on ZMP.It has no stable support region.And the walking motion has better dynamic features.In this thesis,the motion control thesis of underactuated biped robots is studied based on a planar biped robot platform.Based on the simplified model of planar-five-link,a walking control strategy is proposed for underactuated walking and a motion controller is designed.The main contributions of this thesis are:1.A design method of feedback and feed forward controller is proposed to solve the problem of body balance in the process of underactuated walking.2.A motion planning method based on the system states is presented to solve the problem of the motion planning of the swing leg in the process of underactuated walking.To realize the motion track:ing of the swing leg,a motion controller based on the dynamics of flexible joint actuator is designed.3.An estimation method of walking velocity is presented.The method fuses the information from different sensors on the platform.Based on the analysis of the simplied model of the underactuated state,a walking velocity control method that modifies the walking parameter online based on the walking velocity feedback is presented.It ensures the walking velocity stability.