Research On The Mechanism Design Of Manipulator And Figure Kinematic Model Of Machine Tool Control Panel

At present,under the macro background of increasing labor cost and accelerating transformation and upgrading of the manufacturing industry,mechanical arm is applied in all walks of life.According to the use environment,the end-effector used by mechanical arm varies greatly.This paper designs a multi-finger manipulator which can operate CNC(Computer numerical control)machine tool panel by automatic control technology.Through the research on the mechanical structure,kinematics model,dynamics model,the minimum grasping force of fingertips,the minimum contact force of keys and the control system of the manipulator,the main results of this paper are as follows:First,according to the operating object of the control panel of the CNC machine tool,determine the size parameters and load parameters of the manipulator,according to bionics and actual operation,determine the finger index and degree of freedom of the manipulator.This paper summarizes the main driving and driving modes of the multi-finger manipulator at the present stage,from which the optimal scheme of the manipulator suitable for the design of this paper is chosen.Meanwhile,the rotation Angle sensor and pressure sensor suitable for the manipulator are selected,and a virtual prototype is created through NX software.Secondly,the forward kinematics and inverse kinematics of the single finger of the manipulator are analyzed by the theory of robotics,and the workspace of the manipulator is obtained.The error transformation formula of finger structure was established by MD-H method,the tolerance of each part was determined according to the size and precision of the manipulator,and the offset between the actual and theoretical gestures was calculated by monte carlo simulation method.Then,according to the manipulator operation of the machine tool panel to perform the operation task,combined with the human hand in the grasp of the target object analysis grasp mode.Through the kinetic analysis of the finger by the Lagrange method,the mapping relation between joint torque and rotation Angle is obtained,and then the mapping relation between the contact force of the finger and joint rotation Angle is obtained by static analysis.According to the closing condition of the fingertip grasping force,the grasping constraint condition of the finger in three contact models is obtained,and the minimum contact force of the finger when the manipulator grasps the target object under the condition of the contact point model is calculated by the hybrid penalty function method.Based on the contact theory,the minimum contact force of the fingertip during keystroke operation is calculated.Finally,the curve of angular displacement,angular velocity and angular acceleration of the manipulator in the joint space with time was obtained through MATLAB analysis of the trajectory planning of the finger of the manipulator in joint space using cubic polynomial interpolation and cubic polynomial interpolation respectively.Through the method of MATLAB and ADAMS co-simulation,the manipulator control system of PD controller was successfully built in Simulink,and the influence of the above two trajectory planning methods of finger button operation was compared and analyzed.