基于带反馈Hopf振荡器的六足机器人斜坡步态发生器设计

Gait Generator of Hexapod Robot on Slope Terrain Based on Hopf Oscillator with Feedback

为了提高六足机器人斜坡运动的稳定性,基于三支撑足步态,分析六足机器人的斜坡运动,得到斜坡运动静态稳定裕度与躯体俯仰角的定性关系;研究带反馈Hopf振荡器的输出特性与收敛系数、反馈量之间的关系,并设计基于带反馈Hopf振荡器的单腿三关节信号和斜坡步态发生器模型;确定收敛系数的组合,并引入躯体俯仰角构造反馈信号,实现在只改变膝关节摆角而不影响步态其他特性的情况下提高六足机器人斜坡运动的稳定性;搭建Matlab-ADAMS联合仿真平台与实物样机进行验证。仿真表明:与Hopf模型相比,基于带反馈Hopf模型六足机器人上12°斜坡稳定裕度提高6.3%,下12°斜坡稳定裕度提高7.2%;试验表明:在12°斜坡上前进1 m时,基于Hopf模型的六足机器人向左偏移0.3 m,基于带反馈Hopf模型的六足机器人向左偏移0.05 m,稳定裕度显著提高。

To improve the walking stability of the hexapod robot on slope, based on the tripod gait the walking stability of hexapod robot on slope terrain is analyzed, and the relationship between static stability margin and pitch angle of body is acquired. The relationship between the output characters of Hopf oscillator and the convergence coefficient, variable feedback are studied, joint signals generater of the single leg and the coupling model between legs are designed based on feedback hopf model. Choosing the group of convergence coefficient, and bringing in the pitch angle to construct feedback value, in order to improve the stability of hexapod robot’s walking on slope terrain just by changing the knee angle. Union simulation platform of Matlab-ADAMS and physical prototype for testing are constructed. The simulation result is that the stability margin of walking up 12° slope terrain is increased by 6.3 percent and the SM of walking down 12° slope terrain is increased by 7.2 percent compared with the Hopf oscillator. The experiment result is that at the same condition of walking 1 meter, the offset to the left is 0.3 meter under Hopf model, the offset to the left is 0.05 meter under feedback Hopf model. The stability margin improves observably.