为防止机器人在运动过程中与人相撞,提高机器人运动的安全性,提出一种基于危险指数最小化的机器人安全运动规划方法。该运动规划方法把机器人的运动分为全局安全路径规划、在线实时安全轨迹规划、实时避碰控制和目标再搜索等四个阶段。基于人机之间的距离、机器人惯量、人机之间相对运动速度等因素,对每一阶段进行危险程度的评估,得到危险指数,以危险指数最小化为目标规划各阶段机器人的运动。建立三自由度机器人与人共处数学模型,并在 Matlab 下对不同阶段的运动规划进行仿真。为了进一步验证算法有效性,搭建了工业机器人安全运动规划试验平台,实现了基于危险指数最小化的安全避碰。仿真与试验结果表明,基于危险指数最小化的机器人安全运动规划,可以有效确保人在机器人工作环境中的安全性。
In order to prevent robot colliding to human, and improve robot safety during motion, a method of robot safe motion planning based on minimized danger index is proposed. The motion planning of robot is divided into four steps which include global path safe planner, real-time safe trajectory planner, real-time anti-collision controller and goal re-searching. The danger degree can be estimated based on the robot inertia, the distance and relative speed between robot and human during every planning step, and it described as danger index. The motion of robot can be planned by minimizing the danger index. A mathematic model including a 3 degree of freedom robot and human is established. Every motion planning step is simulated in Matlab. To further verify the validity of the planning algorithm, a safe motion planning experiment platform of industrial robot is established, and safe avoiding collision is realized based on minimized danger index. The simulation and experiment results show that this robot safe motion planning method based on minimized danger index is capable of ensuring human safety in coexistence environment of robot and human.