Research And Design Of Robot Modular Gripper

Robot end effectors is a key part of a robot,which directly contacts to the target operating object.Its working performance is an important direction in the field of robot research.The end effector includes a humanoid robot hand which is mainly used in humanoid robot and industrial robot end effector which is often used in automatic manufacturing line of industry.Due to the diverse needs of the market,it is difficult to meet the manufacturing requirements of cooperation for a single productor.Modular thinking meet the market requirements by repeating the products with different performance or different specifications.In this dissertation,we designed an underactuated end holder,which is designed to hold a variety of different clamping characteristics by using modular design.This dissertation takes the three finger end holder as an example,carrying out the kinematic analysis,mechanical analysis,Adams simulation and subsequent experimental verification.Firstly,the principle of the operation is analyzed,and the four bar mechanism is chosen as the function mechanism to realize the movement of the finger.After the design of four bar mechanism is completed,the movement trajectory of the finger is calculated according to the joint movement characteristics of the human finger,and the desired function is obtained by using Lagrange interpolation.The four bar mechanism is optimized by using the complex method with the interpolation function as the expected function.Then,the relation formula of space displacement transformation is obtained by using the method of complex vector.The movement track of the finger is obtained by using matlab.The static analysis of the holder is carried out based on the principle of virtual work,and then simulation is done using Automatic Dynamic Analysis of Mechanical Systems.According to the torque's influence of torsion spring to the contact force curve of the end holder,we picked out appropriate torsion spring,and then simulated the final curve of contact force.Again,the end gripper is 3D printed to reduce the quality of the mechanism.In order to ensuring the accuracy and stability of the transmission,standard part is selected as end gripper's transmission part.The driving part of the end clamping device is combined by STC51 single chip microcomputer and stepping motor.The motor's movement is controlled by MCU,and then the power is transmitted to the clamp finger through the screw nut.The contact force data acquisition program is designed using Lab VIEW,the collected data is first displayed on the chart and then stored in a spreadsheet.Lastly,experiments are made to select objects that are similar in shape and mass with simulation and the actual contact forces change curve are measured.The trend of the curve is consistent with the change of the change of adams simulation,which shows that the simulation results are reasonable,and the end gripper designed can complete the task perfectly.