Wang Zhen, Kou Lei, Ke Wende, Chen Yuhan, Bai Yan, Li Qingfeng, Lu Dongxin
Department of Mechanical and Energy Engineering, Southern University of Science and Technology, Shenzhen 518055, China.
Institute of Oceanographic Instrumentation, Qilu University of Technology (Shandong Academy of Sciences), Qingdao 266075, China.
Biomimetics (Basel). 2023 Mar 21;8(1):126. doi: 10.3390/biomimetics8010126.
At present, the research and application of biped robots is more and more popular. The popularity of biped robots can be better promoted by improving the motion performance of low-cost biped robots. In this paper, the method of the Linear Quadratic Regulator (LQR) is used to track a robot's center of mass (COM). At the same time, the whole-body-control method and value function generated in the process of tracking COM are used to construct the quadratic programming (QP) model of a biped robot. Through the above method, the torque feedforward of the robot is obtained in the Drake simulation platform. The torque feedforward information of the robot is transformed into position feedforward information by spring compensation. In this paper, open loop control and spring compensation are used, respectively, to make the robot perform simple actions. Generally, after the compensation method of spring compensation is adopted, the roll angle and pitch angle of the upper body of the robot are closer to 0 after the robot performs an action. However, as the selected motion can introduce more forward and lateral motions, the robot needs more spring clearance compensation to improve performance. For improving the motion performance of a low-cost biped robot, the experimental results show that the spring compensation method is both reasonable and effective.
目前，双足机器人的研究与应用越来越受到关注。通过提高低成本双足机器人的运动性能，可以更好地推动双足机器人的普及。本文采用线性二次型调节器（LQR）方法来跟踪机器人的质心（COM）。同时，利用跟踪COM过程中生成的全身控制方法和价值函数，构建双足机器人的二次规划（QP）模型。通过上述方法，在Drake仿真平台上获得机器人的转矩前馈。通过弹簧补偿将机器人的转矩前馈信息转换为位置前馈信息。本文分别采用开环控制和弹簧补偿，使机器人执行简单动作。一般来说，采用弹簧补偿的补偿方法后，机器人执行动作后上半身的滚转角和俯仰角更接近0。然而，由于所选运动可能会引入更多的向前和横向运动，机器人需要更多的弹簧间隙补偿来提高性能。为了提高低成本双足机器人的运动性能，实验结果表明弹簧补偿方法是合理有效的。
