Research On Leg Configuration Design And Cushion Locomotion Control Of Quadruped Robots

With the development of robotics,more and more applications of robot are required,and the working environment is getting more complicated.Because of its excellent ability to adapt to the environment,legged robot become a major hot spot of present research.As the research of legged robot promoted,people are gradually dissatisfied with the situation that robot can only walks on a flat ground at a low speed.It is hoped that the robot can move at a high load and high speed and be able to adapt to complex and complicated environments such as forests and caves.However,when a robot moves in a complicated environment at a high speed,how to reduce the impact caused by the interaction of the foot and the ground is an important and imminent problem.In response to this problem,in this paper,we plan to do some research on the leg construction design of the quadruped robot,stable locomotion control and cushion motion control.And mainly breakthrough the cushion motion control problem.We plan to propose a complete set of cushion motion control methods based on force control,equipped the robot leg the ability of cushion.So the robot can move at a high speed while reducing the negative influence of impact on the robot.On the part of bionic configuration design,a bionic quadruped robot driven by motors will be designed.Different from the traditional leg construction with all joint motors placed in each joints,this paper intends to mount all three motors on the hip joint,so as to greatly reduce the overall moment of inertia of the robot leg.The stable locomotion control of quadruped robot is to design a control scheme that can make the robot move stable,which is the basic ability that every robot must have.In this paper,we plan to use static stability margin as the stability criterion to designs a set of gait pattern and foot-end trajectory based on position control mode.Which enable the robot walking steadily in the position control mode.The position control mode can make the robot walk to the planned position,but it cannot control the force that the robot interacts with the environment directly during walking.Therefore,when the position control mode is adopted,in order to reduce the negative influence of robot impact on the stability of the robot,it is necessary to slow down the robot during the foot-raising and the foot-falling stage,and the robot cannot perform jumping and other actions,which severely restricts the robot's working environment.In response to the shortcomings of the position control mode,in this paper we plans to design a force control method named compliance control to make up for the lack of position control mode.The central idea of the control method is that each leg of the robot is equivalent to two sets of spring damping models,so the impact force will not directly impact the robot hardware with the virtual spring damping characteristic.With this feature,the robot leg have the ability of self-balancing and cushion.So as to reduce the negative influence of foot-end impact on the robot without deceleration.