| This thesis takes SCARA robots as research object, builds robot Kinematicsequations and solves the Jacobi matrix, gets singular positions. The author usesparameter identification method to obtain the accurate Kinetics model and designs arobot robust controller. The main researches are listed as following:Firstly, this thesis introduces the structure and application of SCARA robot.Using the modified D-H method to build the kinematics model of robot, In order toverify the equations, the robot motion is observed through MATLAB toolbox.Analytic method is utilized to solve robot inverse kinematics equations. The optimalinverse solution is selected from the four groups of solution. Moreover, the Jacobimatrix of SCARA robot is got, so as to get singular positions in the movementprocess of robot.Then, SCARA robot dynamics equation is built up using Lagrange method. Inorder to simplify the process of parameter identification, the four-joint robot issimplified to two links. By comparing torques in ADAMS, the feasibility ofsimplifying is validated. The kinetic equation is transformed into a linear form toget the observation matrix and the parameters to be identified. Using geneticoptimization method, an incentive trajectory and estimates is designed. And usingleast squares method, the value of the identified parameters was calculated. A jointsimulation is set up using Matlab and Adams, which brought out the kinetic modelof parameter identification. In order to validate such kinetic model, the joint torquesin the same trajectory is compared. The results shows that the identified parametersare closer to theoretical ones, which confirms that the result of kinetic equation iscorrect.Finally, a robust controller is designed according to external disturbances ofthe SCARA robot in the actual circumstances. The purpose of the controller and thetesting standard are given. On the basis of dynamic compensation, the trajectoryerror signal is introduced to as an auxiliary signal in this thesis, based on which thecontroller is designed. The stability of the auxiliary signal and the controller areboth proved theoretically. Two types of trajectory tracking, which are in the absenceof disturbance errors and in some disturbance errors, are observed and compared in the joint simulation. Simulation results show that the error is reduced by50%afterusing the controller, which illustrates the designed robust controller meets thedesign requirements. |
