基于虚拟模型的四足机器人控制策略

Control Strategy of Quadruped Robot Based on Virtual Model

为提高四足机器人在对角小跑(Trot)步态下的行走稳定性,并减小控制策略的复杂程度,提出了一种基于虚拟模型的四足机器人控制策略;将四足机器人控制策略分为支撑相及机身运动控制、摆动腿相运动控制及足端轨迹规划三部分;在Trot步态下行走时支撑相中存在的前后对角支撑足,在分析四足机器人支撑足受力情况后,并添加相关的约束条件,实现了四足机器人足端力及力矩可控;并通过在四足机器人机身的质心位置添加相应的虚拟弹簧阻尼组件,实现了四足机器人姿态和高度控制;通过在摆动腿足端实际位置与环境之间添加虚拟的弹簧阻尼组件并结合足端轨迹规划实现了四足机器人柔顺行走以及足端轨迹跟踪精确性;通过Matlab和CoppeliaSim建立联合对比仿真验证了控制策略的有效性和优越性。

In order to improve the stability of the quadruped robot in Trot gait and reduce the complexity of control strategy,a control strategy of quadruped robot based on virtual model was proposed.The control strategy of quadruped robot is divided into three parts:support phase and body locomotion control,swing leg phase locomotion control and foot trajectory planning.The forward and backward diagonal supporting feet existed in the supporting phase of Trot gait.After analyzing the stress situation of the supporting feet of the quadruped robot,related constraints were added to achieve the controllable force and torque of the quadruped foot.The attitude and height control of the quadruped robot were realized by adding corresponding virtual spring damping components in the centroid position of the robot body.By adding a virtual spring damping component between the actual position of the swinging leg and the environment and combining with the foot trajectory planning,the flexible walking and foot trajectory tracking accuracy of the quadruped robot were realized.The effectiveness and superiority of the control strategy are verified by establishing a joint comparison simulation through Matlab and CoppeliaSim.