| With the development of selective laser melting technology,the development of multi-laser SLM equipment is becoming faster and faster,but the research on multi-laser scanning algorithm is still relatively small.Most studies use single laser repeated scanning to simulate multi-laser lap.However,the overlap of multi-laser is determined by the multi-laser filling allocation algorithm,so it is limited to judge the overlap by the number of scanning lines.In order to better improve the printing efficiency,the distribution of multiple lasers is also a key point.If the distribution of multiple lasers is uneven,it will lead to the fact that when the device prints a certain layer of the workpiece,the printing operation of a certain laser needs to be completed first,and it needs to stop the action and wait for other laser printing to complete before entering the next layer of printing,which will result in waste of resources.Based on the design of multi-laser scanning algorithm,a single and multi-laser scanning algorithm is proposed to reduce the filling time of the workpiece and improve the processing efficiency.The main research contents of this paper are as follows :(1)A block scanning strategy with fill-follow block is proposed.In this method,when the workpiece is divided into blocks,the filling inside the block is preset.As the block is completed,the filling inside the workpiece is also completed.Among them,the process of partitioning simulates the algorithm of ordered edge table method,which reduces a large number of intersection operations between every two line segments and improves the efficiency of partitioning.The filling process also focuses on the uniformity of the filling line distribution.After determining the size of the block and the internal filling spacing,the filling inside each block is kept uniform by intelligent adjustment of the algorithm.(2)An algorithm of internal filling line upwind printing is proposed.According to the circulation wind direction of the SLM printer,if the block internal filling selects the bidirectional scanning,the algorithm will automatically adjust the order between each scanning line;if one-way scanning is selected for intra-block padding,the algorithm adjusts the direction of each scan line in addition to automatically adjusting the order between each scan line,ensuring that no matter which strategy is chosen,the algorithm can maintain overall upwind printing.(3)Several multi-laser allocation algorithms based on partition algorithm are proposed.This method can reasonably allocate the filling line to different lasers,so as to improve the machining efficiency of the workpiece.Among them,direct multi-laser allocation based on block is an application of partition scanning algorithm.Using the existing partition to allocate laser,it can be directly applied to single laser and multi-laser scanning,and can be evenly distributed in multi-laser allocation.In the algorithm of cutting and distributing laser by dividing line,a method of using dynamic dividing line is proposed to ensure that the dividing line will not overlap with the change of filling layers,but the distribution of each layer is uniform.(4)A time prediction algorithm based on partition algorithm is proposed.This method can estimate the processing time of different laser and distribute laser evenly.The time prediction algorithm is also an application of the partition scanning algorithm.The time the block as the unit to predict and accumulate the time,and quickly obtains the prediction time of laser processing. |
