| Motion trail is an important issue in the field of robotic applications.For the four-axis palletizing robot,it will directly affect the palletizing efficiency if the running time is not optimal or trajectory is not smooth.Aimed at the efficiency requirements of palletizing robot,this paper proposes an optimal trajectory planning scheme based on optimal time.The position of joint space corresponding to space sequence task is calculated by kinematics inverse solution,and then using cubic spline interpolation method to make the angular displacement,angular velocity and angular acceleration continuous.Under the constraints of angular velocity,angular acceleration and angle acceleration,the pattern search algorithm is used for the optimal time of robot trajectory planning.The results of simulation and test show that trajectory planning can provide an ideal trajectory and can also improve the work efficiency of palletizing robot.At the same time,based on D-H parameters to establish the kinematics model of the robot palletizing,but due to various factors such as manufacturing,assembly,friction,inevitably will cause absolute positioning error of the robot body,using Leica AT901-B laser tracker to get real coordinates,and through the encoder to obtain the axis angle values.All the D-H parameters are calibrated,and the levelness of the robot is considered.At the same time,the basal plane is calibrated,the calibration equation is built,using the method of least squares to identify the error parameter,and calculating the modified D-H kinematics model to improve absolute positioning accuracy. |
PDF Full Text Request