基于模板CAD模型的任意位姿注塑件抛光轨迹生成与重用方法研究OA北大核心CSTPCD

With the development of intelligent manufacturing technology,the application of robots in the field of processing has been widely concerned,especially in labor-intensive product processing applications,such as shower parts polishing in the bathroom industry,laser cutting of stamping parts in the automotive field and raw edge polishing of injection parts in the field of shoes and clothing.However,the development trend of small batch and multi variety products has put forward higher requirements for the processing efficiency and flexibility of robots.To this end,the work aims propose a CAD model-based method for generating and reusing polishing trajectory of parts with arbitrary position and posture. Based on the known template CAD model information,the local coordinate system was established,the polishing feature lines and polishing regions were extracted,and a series of machining trajectory points were generated by equidistant section method.Further,in order to improve the generation efficiency of polishing trajectory,a method was proposed to directly calculate the processing trajectory of similar products according to the characteristics of the model,so as to realize the reuse of polishing trajectory of similar models.Then,multi-line structured light technology was used to quickly measure the 3D information of the part under the current posture,and the transformation relationship between the part model and the template CAD model was calculated by the 3D point cloud matching method.Finally,combined with the hand-eye calibration results,the robot polishing trajectory of parts with arbitrary position and posture could be calculated. The raw edge polishing of injection molding products was taken as the object of simulation and experimental verification.First of all,the simulation results showed that the robot could move to the correct polishing position by the arbitrary posture polishing trajectory generated by this method.In addition,the experimental results of the built hardware system showed that the proposed method could effectively transform the trajectory of the ideal robot posture to any part posture,which provided a good basis for further processing.The advantages of the proposed method lie in the following three points.First,usually a complete model reconstruction needs to be measured from at least 3-4 different views and data from different views need to be unified in coordinate system,which cannot be applied to online real-time measurement.However,the method proposed only needs to be measured from one view,enables significant improvements in the efficiency of object measurements and trajectory calculations.Further,it is very difficult and time-consuming to calculate polishing trajectory directly based on measuring point cloud.To tackle this issue,the CAD model is adopted to generate the machining trajectory in advance and then only a single view measurement data are need to align with the CAD model,which can complete the transformation of the trajectory effectively.In addition,combined with the hand-eye calibration results of the robot,the polishing trajectory of the parts with arbitrary position and posture can be quickly calculated. The proposed method can realize the efficient generation of robot polishing trajectory based on CAD model,and can realize the trajectory calculation of arbitrary position and posture through trajectory transformation,which improves the efficiency and flexibility of robot polishing trajectory generation.