机器人多指手的多目标优化抓取规划

针对有摩擦点接触条件下的多指抓取模型,借鉴人手抓取经验,提出了接触安全裕度概念.通过修正摩擦锥约束条件,建立了具有一定接触安全裕度的非线性内力优化模型,用于求解合适的接触力.为获取最优的抓取位形,将物体位姿参数作为变量,确定接触力与多指手关节力矩的关系,基于多指手关节空间内的转角位置度和相对承载能力性能指标,建立了多指抓取的多目标优化模型.最后,以三指手抓取系统为例进行了分析求解,并利用多目标粒子群优化算法进行物体位姿规划,获取了规划模型的非劣解前沿.结果表明,该方法能在保证安全抓取条件下,有效改善多指抓取的综合性能.

Multi-objective optimization grasping planning for multifingered robot hand

Aiming at the multifingered grasping model under the condition of point contact with friction,the concept of contact safety margin is proposed according to the experience of human grasp.The nonlinear optimization model of internal force with contact safety margin is built by modifying the constraint condition of friction cone,and the corresponding contact force can therefore be obtained.In order to obtain the optimal grasping pose,the relationship between joint torque and contact force is established by taking object pose parameters as variables,and the multi-objective optimization model of grasp is built based on the performance indices including position-grade and relative loading capability in the joint space of robot hand.Finally,a three-fingered robot hand grasping object is calculated and analyzed,and multi-objective particle swarm optimization algorithm is applied to plan the object pose and a set of non-dominated solutions is also obtained.The results demonstrate that the proposed method can efficiently improve grasping performance under the condition of safe grasping.