基于虚拟模型和加速度规划的腿部缓冲策略

提出一种基于虚拟模型控制和加速度规划的腿部缓冲方法。通过建立机器人腿部的虚拟模型,设定落地过程中躯干加速度从而可减小地面对机器人的冲击力,保护机器人的机械结构。该方法将机器人的落地过程分为下落、缓冲、恢复3个阶段。在下落阶段,通过在足端与期望位置之间添加虚拟“弹簧—阻尼”系统来控制足端位置。在缓冲阶段和恢复阶段,通过规划躯干质心加速度,从而减小落地过程中躯干受到的冲击。该方法可避免在激烈的足地交互过程中调节系统的刚度和阻尼,控制过程更简单精确。基于Webots的仿真试验表明,该方法在机器人落地过程中的保护是有效的。

Buffering strategy for articulated legged robot based on virtual model control and acceleration planning

Based on virtual model control and acceleration planning, a buffering strategy was proposed to protect the articulated legged robot for landing. Through virtually modeling the robotic leg, the torso acceleration during landing was specified so as to reduce the impact force acting on the torso. According to this buffering strategy, the whole landing process could be divided into three phases, the falling, buffering and recovering phases. In the falling phase, the robotic foot was correctly positioned by a virtual “spring-damping” system to achieve the appropriate position according to the actual position. In the buffering and recovering phases, the acceleration of center of mass of the robotic torso was planned so that the impact acting on the torso was reduced. Adjusting stiffness and damping parameters were avoided at the moment of foot-to-ground contact in this buffering strategy, rending a simple but accurate landing control. The simulation based on Webots protocol revealed that this buffering strategy was effective in protecting the robot against damage during landing.