Collision-free Five-axis Continuous Scanning Path Generation And Verification For Free-form Surface Inspection

Different from the traditional point-by-point inspection method,recently a new five-axis continuous inspection technology has been developed,which can scan a surface continuously by sweeping the stylus tip along a predefined sweeping curve on the surface.Therefore,its inspection efficiency is leaped to a new level.Also,it is becoming a popular and dominant way for accurate and efficient inspection of free-form surface.However,current research in inspection path generation has mainly focused on traditional three-axis and three + two-axis CMM inspection,without adapting to the case of five-axis continuous inspection CMM.At the same time,regarding the issues of collision avoidance,to the best knowledge of the author,there is no academic research done for the five-axis continuous inspection.Because the kinematic configuration of five-axis inspection machine is exactly the same as the double spindle-tilt five-axis machine tool,and some of the methods and ideas for the collision avoidance in five-axis machining,can be borrowed here.In this paper,firstly,beginning with the definition of the five-axis continuous scanning path,the mathematical theory of five-axis continuous scanning path generation for free-form surface inspection is introduced,and then a collision-free five-axis continuous scanning path generation method is proposed.Firstly,the guiding curve for defining the sweeping path is generated based on the parameter domain of the freeform surface.Then,an efficient geometric-based method is proposed to calculate the V-map of points on guiding curve with considering the inspection requirements of the five-axis inspection machine;Based on the V-map,a new idea called Composited Visibility map(CV-map)was proposed specifically for representing the real accessibility condition for the five-axis sweeping path.After that,based on the guiding curve and the calculated CV-map,stylus axis direction of each sample point is determined,which could guarantee collision-free and good inspection efficiency at the same time,could be defined and the final inspection path could be generated in this way.Finally,the collision-free five-axis continuous scanning path generation method are validated through an application case.Design a CMM application software which based on I++ DME,import the inspection path into the application software to complete the scanning process and obtain the measurement results.And use the existing solution in industry as a control,compared with the experimental results and the measurement efficiency to draw a conclusion.