Máquina de medir por coordenadas utilizando microcontrolador e sistema supervisório

Abstract

A Coordinate Measuring Machine (CMM) consists of sophisticated equipment for three-dimensional measurement of parts that can be quite complex or require a high standard of quality. The implementation of such a machine in a quality control department allows the realization of measurements at an accuracy and speed impossible by conventional means. The design and construction of an CMM requires the integration of technologies related to programming, mechanical engineering, electronics and control. The developed project resulted in the construction of an CMM with a satisfactory measurement execution capacity, acting autonomously and with sufficient resolution for several applications in metrology. The development of the work involved mechanical design and construction of the structure and mechanisms, electronic design, manufacturing and integration of electronic components programming of the control system and programming of a supervisory system for operation interface. The supervisory system aims to integrate the control system of the CMM, performed through a microcontroller, into a microcomputer, where the supervisory system performs part of the control and monitoring of the machine, as well as its main function, which is to present the results of the measurements in execution. This integration requires the configuration of a communication protocol that is responsible for the data traffic of the machine. Through this feature the data collected by the machine can be displayed intelligibly on a computer monitor. The main control of the equipment, which concerns the displacement of the actuator, called probe, is performed manually for safety reasons. The programming of the control system requires not only the execution of the displacement mechanism of the machine but also a logic that monitors that displacement and presents it in data form to the supervisory system. The supervisory system processes this data and displays it as measurement values on the interface developed to be displayed on the computer monitor. The main objectives of the work are: to implement the integration of the control system with the supervisory system via network communication protocol; and propose the construction of a machine capable of performing reliable three-dimensional measurements having been constructed with relatively low cost. The tests and demonstration of the results are integral parts of the work, as well as the explanationof the methodologies applied. The results of measurements taken after the completionof the CMM have demonstrated the efficiency of the equipment produced. Although not as accurate as a CMM developed by specialized manufacturers, the machine is perfectly capable of being applied to a large number of applications in the industry.