A Time-Optimal Velocity Planning Algorithm with Machining Precision Constraints for CNC System

In order to realize the high-speed and high-precision machining, a time-optimal velocity planning algorithm with precision constraints for CNC system is proposed. The algorithm takes the total machining time of the given trajectory as optimization target. On the basis of kinematic constraints, in order to ensure the machining accuracy, the precision constraints are introduced for the two-dimensional trajectory and three-dimensional trajectory respectively, including chord error, tracking error and contour error constraints. In order to solve the above nonlinear optimization model, the two-step optimization strategy is adopted to transform the nonlinear optimization problem into two convex optimization problems. A smooth time-optimal velocity planning algorithm with precision constraints are realized. Performance of the presented algorithm is evaluated both by simulations and experiments.