Feed-rate Scheduling Optimization Method Based On Mapping Of Lateral Feature Lines

In CNC machining process,feed-rate scheduling is of great significance in terms of machining efficiency and precision.FRI(Feed-rate interval)based method is a common feed-rate scheduling method which partitions the cutter path into several intervals and a uniform feed-rate is specified in each of them with the goal of reducing degree of fluctuation of feed-rate on the cutter path and improving the continuity of schedule feed-rate profile.Traditional feed-rate scheduling methods generate FRIs by setting feature points identified on the cutter path as their boundaries.Due to the incorrectness of identified feature points and the position of boundaries of FRIs are strictly limited on that of cutter points,problems like misplacement and loss of boundaries of FRI on several paths can easily occur,thus causing inconformity of scheduled feed-rate among several cutter paths,eventually undermining the machining precision.To solve problems mentioned above,the method of lateral uniformization of feed-rate based on lateral feature lines is proposed in which lateral feature lines are mapped onto cutter paths and generated mapping points are set as boundaries of FRI.The goal of lateral feature lines which come from identified feature points is to overcome problems related with identified feature points,in the meanwhile,the position of boundaries of FRI is no longer limited on that of cutter points and can be located anywhere on the cutter path.Due to character of mapping,boundaries of FRI will be distributed along the lateral feature lines,the degree of lateral uniformization of boundaries of FRI is greatly improved,thus improving degree of uniformization of scheduled feed-rate on several cutter paths.The algorithm has been evaluated on Huazhong CNC system through multiple simulation and experimentation processes,the result shows that the degree of scheduled feed-rate on various cutter paths are greatly refined,thus proving validity of this algorithm.Meanwhile the algorithm is robust,highly time-efficient and has good application for various kinds of parts.