In order to reduce the mechanical damage caused by apple harvesting robot to apples and realize the non-destructive grasping during the grasping process, an adaptive impedance control strategy for apple harvesting robot compliant grasping is proposed based on the analysis of grasping modes in this paper. Firstly, burgers viscoelastic model is established to describe the rheological characteristics of apples. Then taking the plastic deformation of apples as the damage standard, three types of grasping modes of the gripper for picking apples are compared and analyzed. Finally, in view of the fact that the traditional impedance controller cannot satisfy the grasping force control under the condition of uncertain environmental stiffness and uncertain environmental position, an adaptive controller is designed to adjust the desired position online based on the error between desired force and actual grasping force so that it can track the desired force. Simulation and experiment results show that the adaptive impedance control strategy is more compliant with the actual grasping force, the overshoot and the adjustment time has been significantly improved, which provides a reference for actual apple picking.

为了减少苹果收割机器人对苹果的机械损伤，实现抓取过程中的无损抓取，在分析抓取方式的基础上，提出了一种适合苹果收割机器人顺应性抓取的自适应阻抗控制策略。首先，建立了汉堡的粘弹性模型来描述苹果的流变特性。然后以苹果的塑性变形为破坏标准，对苹果采摘夹具的三种抓握方式进行了比较分析。最后，鉴于传统的阻抗控制器在不确定的环境刚度和不确定的环境位置的情况下不能满足抓力控制的事实，自适应控制器被设计为基于期望力和实际抓握力之间的误差在线调整期望位置，以便它可以跟踪期望力。仿真和实验结果表明，自适应阻抗控制策略更符合实际抓握力，显着改善了过冲和调节时间，为实际采摘苹果提供了参考。