Research On Grasping Performance Of Pneumatic Soft Gripper

The robotic gripper as an end effector is an important part of the robot's grasping operation.With the increasing application of industrial automation arnd the increasing variety of handling objects,traditional robotic grippers are difficult to meet the requirements for soft grasping of soft and fragile items.The soft grasping device has good flexibility and has broad application prospects.Since the research on the soft gripper is mostly limited to the device structure,in order to better integrate the soft gripper into the automatic production,this paper designs and fabricates a pneumatic soft gripper with soft fingers according to the working principle and manufacturing process.Combining the characteristics of soft fingers with the grasping theory,the fingertip grasping and envelope grasping performance of pneumatic soft gripper are studied,and the theoretical model is verified by experiments.The main research contents are as follows:The mechanical properties of single finger were studied,and a mapping model of finger mechanical properties based on artificial neural network is proposed.Based on the Yeoh model,a mathematical model of the relationship between soft finger bending angle and inner pressure was established.The relationship between inflation pressure,finger bending angle and fingertip force was studied by finite element analysis.The mechanical properties of soft fingers were tested.The accuracy of the theoretical model and the finite element model is verified.The artificial neural network is used to fit the experimental results,and the nonlinear relationship between inner pressure,finger bending angle and fingertip force is obtained.A fingertip grasping model of a general robot for a general object was established,and stable grabbing and non-destructive grip analysis were performed.With the grasping stability as the optimization goal,the optimal grasping contact position is calculated by genetic algorithm,and the contact force is taken as the optimization target.The minimum contact force is calculated by genetic algorithm,combined with the optimization result and the neural network model.The relationship between inner pressure and grasping performance was designed.The soft grasping test bench was designed to test the grasping ability of the soft manipulator to grasp the fingertip at different pressures.Verified the correctness of the stable grasping model and non-destructive grasping model.An analysis method based on the simplified model of the discrete-link finger is prop osed.The envelope grasping model of the soft gripper is established and the envelope grasping analy sis is carried out.Based on the results of finite element analy sis,the mechanical prop erties of the discrete finger simplified model are fitted by quadratic polynomial.The influence of inflation pressure on the entrapment p erformance of the envelop e is c alculated.The correctness of the envelope capture model is verified by the envelope grasping exp eriment.The grasping experiments on common obj ects in life show that the soft gripper designed in this paper has good adaptability to soft,fragile and p oorly shap ed items.