Construction Of Three Coordinate Measuring System Based On PPCNC Platform

Three coordinate measuring machine is one of the most direct and effective equipment to measure and obtain the size date of the measured object.With the continuous development of machine tools to intelligence and automation, the coodinate measuring machine are increasingly prominent position in all works of life. Traditional three coordinate measuring machine is expensive and maintenance costs high.So it is practical engineering significance to explore the three coordinate measuring system based on personal portable CNC machine tools. The three coordinate measurement system established in this paper is a simple and easy measurement system, which is to measure simple and regular geometric elements, so as to help college students understand the three coordinate measuring machine and the course of the measurement.This paper discusses the function, the external structure and the parameters of PPCNC, and introduces the three coordinate measuring machine. Using PPCNC to build the platform of three coordinate measuring system, and introducing the measurement software based on Mach3VB scripting language.In the process, the measurement of French amount direction measurement principle and measurement point distribution and select the number of measurement principle should be followed.By comparing interpolation and data quasi legitimate, this paper determines the selection of least squares (a data fitting method) for the data processing of coordinate data. The data fitting of basic geometric elements (straight line, plane, circle, cylinder and sphere) is mainly introduced, which lays the foundation for the calculation of the angle and distance between the points, lines and surfaces. In the measurement of geometric shape and position error, the mathematical formula of straightness error, flatness error, roundness error, roundness error, roundness error and coaxial error are derived.VB software has the characteristic of convenient, simple and visual. This paper uses Visual Basic 6.0 to compile the data processing interface, describes the environment of VB6.0 programming window layout and programming ideas, and realizes the data fitting with least square method in VB environment.Circular and cylindrical was selected as the measuring object.Using least square method+VB experiment, LSABC algorithm vb experiment and three coordinate measurement system experiments is to verify the feasibility of the data processing method and the feasibility of measurement system. Taking some points in the circular and cylindrical in SolidWorks to Vertify the feasibility of the least squares method in the VB environment. The reliability of the three coordinate measuring system is verified by measuring the radius of the steel ball.