Development Of The Precise Dimension Measuring Instrument Based On Linear Array CCD

An instrument that measuring precisely one-dimensional size of objects applying lineararray CCD was developed. The paper described working principle, circuit theory, programdesign of the instrument. The main features of the instrument as follows:(1) Selected microcontroller STM32that has32bits Cortex-M3kernel of ARMv7architecture as the core of the instrument; improved integration, reliability andperformance-price ratio of circuits of the instrument applying huge control, computing, storagecapacity of STM32;(2) Designed the characteristic driving circuit of linear array CCD and the acquisitionmodule of video signal; realized the driving timing of linear array CCD applying high-speedIO port of microcontroller STM32and the method of software programming; designed the ADconverting module and acquired reliably the measuring data of linear array CCD based onresearching the features of planar array CCD video acquisition dedicated chip AD9826;(3) Researched the edge detection sub-pixel algorithm of improving the resolution ratio ofCCD, and transplanted to software system of the instrument, thus improving the accuracy ofdimension measuring;(4) Completed the design of control interface of the instrument, mainly including maininterface, measuring interface, data recording interface and setting interface, and made theinstrument have simple operation and convenient data transmission.Completed the making and debugging of prototype of the instrument, and analyzed thetolerance of the instrument.