The Research On Trajectory Interpolation Algorithm Of6-DOF Industrial Robot

The industrial robot technology is a newborn technology that developed in the middle of thelast century, which has precision, intelligent, flexible and other advantages. It is the highestexpression of the level of modern industrial automation technical, and it’s development level hasbecome the standard to measure the level of the industrial automation of a country.Six-Dof Industrial Robot which has six degree of freedom is a special industrial robot, it canreach anywhere to complete corresponding tasks according to the specific trajectory line in thespace. In this paper the trajectory interpolation algorithm of six-dof has been studied and theinterpolation control algorithm with variable step size of scribble track in real time has beenproposed. The main work and results can be shown as follows:Firstly, the coordinate system is established by D-H method on the model of Yaskawa SK66-dof robot, the homogeneous transformation matrix is putted on the base of studying the robotkinematics equation theory deeply to get the forward kinematics formula of robot, the problem ofinverse Kinematics in robot’s kinematics is solved by using separation of variables, and thedeviation is verified by simulation.Secondly, study the theory of Non-Uniform Rational B_Spline (short for NURBS) deeply,the points and derivative vector on the curve is calculated quickly by using the de-Booralgorithm. On the base of study and analysis of the current NURBS curve interpolation algorithm,the interpolation algorithm with variable step size in real time of NURBS curves is proposed tosolve the problem that accuracy and speed of free curve interpolation algorithm of real-time inthe recent motion control system can not get at the same time. In this algorithm, the size of stepwill adjust automatically with the change of deviation and curvature, the step size will reduce atthe curve with big curvature to raise the accuracy, increase at the curve with small curvature toenhance the speed, this algorithm will meet the requirement that the interpolation speed andaccuracy can be got at the same time.At last, the hardware platform is builded to verify the system. The results and data ofsimulation experiment proved that the algorithm improves the interpolation efficiency, enhancesthe system’s real-time, improves the accuracy and speed of interpolation, and it has a highfeasibility in actual production.