Design Of Two Finger Gripper Control System Based On CAN Bus

6DoF manipulators was the tendency of industrial robots.However,the development of end effectors was lagging.The two-finger and multi-finger grippers were general tools which could complete several operations such as handling,palletizing,feeding.The CAN bus is one of the most widely used field buses in the world.In the field of robotics,the CAN bus is gradually replacing RS485 and will become the mainstream communication bus in the robot field.In this paper,with the mechanical characteristics of the two-finger gripper,a controller and general communication interface based on CAN bus was designed.The main tasks are as follows:First,by analyzing the kinematics of the gripper,we obtained the mathematical model of it,in addition two common open-loop control algorithms: trapezoidal acceleration and deceleration algorithms and S-type acceleration and deceleration algorithms,have been analyzed in the article.The gripper has higher requirements for repeatability and should be closed-loop controlled.Combining the advantages of S-acceleration and PID controller,this paper proposed a control algorithm of s-type acceleration and deceleration combined with fuzzy PID for stepping motor.In the second place,we selected subdivision drive as the driving mode according to the driving circuit of several stepping motor,thus a chip named TB6560 was suitably selected as the driver chip for the drive circuit,which highly simplifies the design of the drive circuit,and alleviated the problem of low-frequency oscillation of the motor.Thirdly,considering that the CAN bus ID has a limited number of digits,and the deadline cannot be directly used as a priority to be quantified.In this paper,the logarithm of the cut-off period is used to quantify the average value according to the logarithm of the deadline,so as to obtain the priority.And then,combined with the improved scheduling algorithm,the CAN communication protocol is designed.Finally,the comprehensive experiments demonstrated that the proposed algorithms have obtained a notable achievement on the platform.