Design And Implementation Of A Shearing Robot

Shearing works with scissors is a common operation in industrial and agricultural production and daily life.The shearing robots can replace a part of the manual shearing operation,and perform the shearing operation in places where workers are hard to reach or in a narrow space where workers are hard to work.Power-enhanced shearing robots can complete shearing operations that can't be cut by workers.Thus shearing robots are very useful in practical works.Shearing robots are rare in the market,few information about the robots can be found in mass media.This master thesis represents the design and the sample product of a small shearing robot,which is mainly used to research the automatic control problems of the shearing robots,and lays a foundation for the design of large and medium-sized shearing robots in the future.This article describes in detail the principles of this shearing robot,the design of its hardware and software,and the experiments that confirm its usability.The main contents of my thesis are as follows:(1)The overall design of the shearing robot.The robot is organically composed of drive mobile vehicle,base of mechanical arm,waist joint,shoulder joint,elbow joints,wrist joints,end effectors with scissors,the drive motors and controllers of the joints and the end effector,video modules and image processing software,human-machine interaction system,etc.It can quickly and accurately complete the shearing mission.(2)Innovatively design the end effector of the shearing robot.two different types of end effectors were designed.I have completed the production and experimental verification of the two types of end effectors.It is simple in structure,flexible in works,and very cheap.I have realized the control of the angle and angular velocity of the actuatorservo by use of STM32 single-chip microcomputers,so that we have obtained better results in the motion control,including motion control of the joint and the end effector control.(3)Simulation researches on the MATLAB platform about the motion analysis and trajectory planning of the shearing robot.The DH matrix method was used to establish the positive kinematics model of its manipulator;the analytical method was used to solve the inverse kinematic equation;the simplified dynamic model was established according to the Lagrangian method;and the kinematics,dynamics,and workspace were simulated and analyzed.The design has better feasibility and all parameters are reasonable.The trajectory planning of each joint was studied on the MATLAB platform and the trajectory planning was performed by the fifth-order polynomial interpolation method.The simulation results verified that the shearing manipulator can move quickly and smoothly.(4)Proposed a trajectory tracking control method with sliding mode variable structure,the method is based on radial basis function neural network.The simulation results show that this method has a good tracking effect and greatly reduces the oscillation of the robot arm.(5)Designed the hardware and software of upper computer for remotely controlling the shearing robot.In order to solve the problem of multi-task management,I designed the upper computer on the Labview platform,including the interface of serial communication,interface of motion trajectory control,interface of arm control,interface of end-effector control,interface of image display,etc.The operation process of the robot can be controlled through the communication between Zigbee equipment and robot.(6)Verified the functions of the shearing robot by experiments.I completed control tests,motion tests,and shear tests in our laboratory.The tests results show that the shearing robot can effectively achieve the movement of the wheel and the robot arm,and the end effector can cut off some thin wires,etc.,which shows that my shearing robot can meet the task requirements.The principles and techniques of the shearing robots described in this paper can be used to develop large and medium-sized shearing robots,which will be very effective,such as robots that shear off steel bars in disaster relief,robots that cut off cables in the industrial production,robots that shear off tree branches or pick fruits in agriculture.The results of this project will make some contribution to the development of intelligent robots.