Research On Compliance Control And Bounce Strategy Of Single Leg For Legged Robot

With the continuous development of legged robot,the performance of single leg needed to be improved to achieve the running and leaping gait.Improving tracking effect of single leg when legged robot moved in high speed running or jumping gait,this paper studied the control methods of single joint.The impact force which is equal to numbers of robot gravity is produced between robot and ground when the legged robot moves in high speed.To reduce the impact force,this paper studied the compliance control methods of single leg and the force control methods of single joint.We studied the bounce strategy of single leg to build the foundation for legged robot bouncing.This research whose background was quadruped robot and whose object was single leg included control methods of single joint,compliance control methods and height control of single leg.The main research results of this paper are as follows:(1)To solve the problem which the tracking effect of hydraulic single joint was worse,this paper studied the control methods of it.This paper proposed the control method which based on velocity compensation and parameter estimation,and adopted the sliding mode control to solve the poor robustness of it.According to position servo of single joint,this paper adopted the double loop control method and the inner loop adopted the force control.Based on the above control methods,we obtained better results of the position servo and force tracking.(2)The impact force was produced between foot and ground when the legged robot moved in high speed running or jumping gait.To solve the effect of impact force on legged robot body,this paper studied the compliance control methods.Based on the idea of virtual spring model,the impedance control methods was proposed and applied to single leg control.(3)In the study of single leg jumping movement,the energy orbit stability criterion was proposed.Using energy orbit stability criterion return can well make up the shortcomings which motion states weren't monitored in the flight phase.This criterion was proved by experiments of single leg.(4)The complex model of single leg was simplified to the equivalent model to study the stability of bouncing movement and height control methods.According to the movement characteristics of single leg bouncing,this paper proposed the height control methods which were position control and force compensation.The height control method of single leg based on position planning was verified by experiments.