Abstract:A multidegreeoffreedom fruit and vegetable picking manipulator with a flexible arm was developed according to the bending flexible pneumatic actuators which had large bending capabilities. The static characteristic and deformation of the bending actuators were studied, and then the kinematics model of picking manipulator was established with multiple tandem joints by using homogeneous coordinate transformation and piecewise constant curvature model. At the same time, the grasp force of the picking manipulator when grasp the different objects was analyzed. In order to adapt to different grasp objectives, the grab modes were set when the robot picked the objects, and then the relationship between finger output force and air pressure was studied. Also, the picking manipulator movement track and work space were got by markers position change with air pressure. Through the simulation of the manipulator by Matlab software, it can be seen that the picking robot can complete fivefinger grasping, fourfinger grasping and twofinger grasping gestures by cooperation of flexible fingers. Subsequently, the relevant experiments were carried out to verify the theoretical model. A prototype of the picking manipulator was made and a variety of fruit and vegetable simulation picking experiments were carried out in the experimental environment. The results of harvesting experiments showed that the picking manipulator had flexible movements and high adaptability to the shape of object. It had multiple grasping modes and was easy to control, which can grasp objects of different shapes and weights stably, especially suitable for automatic picking of spherical and cylindrical fruits and vegetables.