Optimal Design Of The Palletizing Robot Mechanism For Pick-and-place Applications In 3C Industry

With the development of science and technology and the improvement of the living standard,the demand of consumer electronics is becoming bigger,which promotes the development of 3C industry's automation.Taking the mobile phone manufacturing industry as an example,the SCARA robots are used widely.But the SCARA robots cost too much for the pick-and-place applications.On 3C production line,production cost is lower and better.Palletizing robot is similar to SCARA robot in kinematics performance which cost lower.However,the pick-and-place applications in 3C industry need higher accuracy and better kinematics performance.It is different with traditional palletizing tasks.In this dissertation,the optimal design of the palletizing robot for the 3C industry has been studied with above consideration.The geometric analysis and coordinate transformation methods are used for calculating the kinematics of the palletizing robot in this dissertation.And a new method for palletizing robot's kinematics has been proposed by simplifying the mechanical structure.The pose error model of palletizing robot is established with joint clearance based on the product of exponential formulation.The error distribution in the given workspace is obtained by numerical calculation and simulation in MATLAB.And the error model is proved rational for the comparison of the error distribution in two cases,the calculations with axial clearance and without axial clearance.The indexes of pick-and-place applications in 3C industry are proposed by analyzing the workspace and the inverse conditional number of SCARA robot and palletizing robot.An optimal design method of the palletizing robot is obtained with the error we have proposed.That includes the joint clearance's constraints and other constraints.After numerical calculation,the pose errors before and after optimization has been compared.It is proved that the optimal design method is useful for reducing the pose error.The structure parameters of the palletizing robot are optimal designed.The maximal joint torque has been estimated throughout the simulation of dynamics in Solidworks based on straight line trajectory planning.It can lead to the selection of motors.