In order to reduce the damage of the robot to fruits and vegetables in the process of picking, a robot flexible grasping test platform is designed, and a gripping force tracking impedance control algorithm suitable for end effectors to grasp fruits and vegetables with two fingers is proposed. The fruit and vegetable gripping system is equivalent to the impedance-admittance model, making the finger force/position control equivalent to the desired inertia-damping-stiffness model, and its parameters can be adjusted as needed to realize the dynamic relationship between the gripping force and the position. It is expected that the deviation between the gripping force and the actual contact force of the collected fruits and vegetables is used as the input of the outer loop force impedance controller, and the controller generates the correction amount for the reference trajectory of the inner position loop. This algorithm only considers the direction of holding fruits and vegetables with two fingers along the end effector, avoiding the complexity of using multi-degree-of-freedom manipulator impedance control algorithm, improving the real-time performance of the control, and at the same time, it has the effect of the uncertainty and force disturbance of the grasping system model. Strong robustness. The robot grasping experiment proved the effectiveness of the two-finger grasping force feedback impedance compliance control algorithm, which can realize the robot's flexible grasping, reduce the damage of grasping fruits and vegetables and ensure the quality. This research can provide key technologies for non-destructive grasping and picking by agricultural robots.

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