| With the development of intelligent manufacturing in our country,industrial robots with visual functions have become more and more important.The Delta Robot-a kind of parallel robot-has the advantages like high speed and high precision,and received widespread attention from various industries since its invention.In this paper,many theories have been studied,such as the forward and inverse solutions of robot kinematics,trajectory planning,coordinates extracted from the camera,system integration and so on.Finally,a Delta Robot with visual pickup function is designed by using the general industrial controller.The analytic method to solving forward kinematics problem of Delta Robot is complicated,so a numerical optimization method-Nelder-Mead simplex method – is used to solve it in this thesis.This method simplifies the complexity of solving the model and reduces the computational complexity,therefore,the forward and reverse kinematics solution of Delta Robot can be completed in a short time.In the process of picking up,the Delta Robot needs to meet several requirements.Such as smooth end-effector trajectory,steady changes of motor speed and acceleration in Cartesian coordinate system.The Delta Robot usually uses gate trajectories in the picking process,so a time-optimal trajectory optimization method is proposed,which uses Pythagorean-Hodograph curve for curve path planning locally and polynomial trajectory planning globally.Delta Robot’s hand-eye calibration and target coordinate point extraction are two main problem in realizing visual pickup function.Based on camera calibration,image processing method is used to obtain the coordinates of the target’s center point.Then,these coordinates are accurately converted to the robot coordinate system.This provides the basis for solving the kinematics of Delta Robot.Through the research on the key technologies of the design and implementation of the Delta Robot,by using the system integration technology,a Delta Robot experiment platform with visual pickup function is engineered based on a general industrial controller.The function of each part of this study is verified in practice,which further proves the validity and engineering value of the research results. |
