Structural Design And Optimization Of Self-Propelled Arm Coordinate Measuring Machine

With the advancement of the China Manufacturing 2025 strategy,the manufacturing industry is gradually turning to automation and intelligence.The demand for online measurement of irregularly shaped artifacts in the production process is increasing.The traditional articulated arm coordinate measuring machine can effectively solve the measurement problem of complex curved surfaces due to its flexible operation.However,due to the manual traction measurement method,the measurement efficiency is low and the human interference is large,which cannot meet the needs of intelligent manufacturing online automatic measurement.In order to realize the online automatic measurement function of the articulated arm coordinate measuring machine,this paper designs a self-driven articulated arm coordinate measuring machine(hereinafter referred to as the measuring machine)body structure,with the corresponding host computer software,can achieve irregular artifacts complex curved surface Online automatic measurement.Analyze the overall configuration of the measuring machine's self-driving scheme,fully fit the structure of the human arm,reasonably allocate the degrees of freedom of the measuring machine,and allocate six degrees of freedom to the three joints of the shoulder,elbow,and wrist to realize the measuring machine probe Flexible adjustment of position and attitude.Taking the maximum measurement space as the optimization objective,the ant colony algorithm was used to solve the optimal combination of the measurement arm size.After analyzing and comparing several common driving methods,the integrated joint module is used as the optimal self-driving scheme of the measuring machine,and the error source of the measuring machine is comprehensively analyzed,and the accuracy guarantee guidance for the overall structure design is proposed.After determining the overall design of the measuring machine,select the probe at the end of the measuring machine,design the probe mounting base,and use the mass attribute measurement function of the SolidWorks software to assist in solving the gravity moment and inertia moment of each joint load in sequence.Select the model of the joint module according to the joint torque,and design the corresponding joint structure according to the size and layout of the joint module.Guided by the analysis result of the error source of the measuring machine,the size and shape tolerance constraints are added to the key dimensions and the mating surface to improve the processing and assembly accuracy of the measuring machine.Based on the structural design,the rigidity of the measuring machine is further analyzed.The static structure of the measuring machine is analyzed for the limit and typical measuring postures.The critical deformation area is found according to its strain distribution,and further stress is applied to the key components.Analysis and targeted structural optimization to improve local deformation of weak links.Finally,the optimization results are evaluated.Under the typical measurement posture,the overall deformation of the measuring machine after optimization is reduced to about 0.1 mm,which meets the design requirements.The first six natural frequencies of the measuring machine are obtained through modal analysis,and guidance suggestions are given for the speed range of the joint module motor.On the basis of structural optimization,according to the MDH modeling method based on homogeneous coordinate transformation theory,combined with the structural characteristics of the measuring machine,the motion transmission coordinate system of the measuring machine is established,and the kinematics of the measuring machine is derived according to the structural parameters of the measuring machine The equation,and finally by comparing and analyzing the calculated value and actual value of the end probe position under different measurement postures,verifies the correctness of the kinematics equation,and provides a theoretical basis and basis for the subsequent development of the host computer control software.Figure[67]table[15]reference[89]...