Research And Development Of Embedded Intelligent Active Measuring Device

Active measuring instrument is widely used in grinding machine, but domestic active measuring instrument has the limitations, for instance, low intelligence, few measuring function, low precision and etc. With the development of machine processing, it can't the requirement of practice. After the theory and application of active measuring instrument having been studied, intelligent active measuring instrument based on embedded system is proposed in this paper to improve this situation, and its overall design of intelligent functions, hardware and software are also described in detail.The design of hardware is started from the frame of hardware and hardware requirement analyze, the serving circuit of inductive sensor is improved, and a new sine wave generator with low cost and high stability is proposed. LPC2214 of ARM7 is used as the control core and intelligent information handling. Peripheral circuit is designed, including data sampling circuit, human-machine interface, RS-232 and nonvolatile memory circuit. In the process of hardware design, product upgrading is considered.Based on the platform of embedded system which is built on LPC2214 controller, ADS1.2 andμC/OS-ⅡRTOS, intelligent software is designed. First, software is divided into tasks, and the tasks are analyzed, such as priority distribution, the inter-relation. Task program flow charts are presented, and upgrading is considered. After the realization of basic function of active measuring instrument, programming for roundness error measurement is emphasized. Moreover, some intelligent features, such as chopping surface measurement, measuring range auto change, auto to zero, nonlinear compensation and fault diagnosis, have been put into practice, which makes the active measuring instrument higher lever of intelligence. The code is optimized to reduce the runtime of program.Anti-disturbance is well designed, a kind of two way response Watchdog is presented, which not only monitors the main routine, but also the timer interruption. Digital filtering algorithm with better filtering and faster response is realized.In this paper, the design of intelligent active measuring instrument is based on embedded system, in the meantime, acquiring the advantage of easy upgrading and maintain, high precision, multi-measuring function, good human-machine interface and higher lever of intelligence. After test, the result shows good performance and extensive application.