Research On The Synchronous Drive Control Techniques Of Quad-Nocular Stereo Measurement

Stereo measurement technology is widely used in aerospace, machinery, automobile,shipbuilding and other industrial sectors.In this paper, some research has been done on thesynchronous control techniques of quad-nocular stereo measurement, and FPGA has been used asmaster controller to make four cameras acquire image data synchronously,to store these image datawhich have been acquired,to communicate with computer and transmit acquired image data to thecomputer for further processing. Main contents of this paper are as follows:1. The module of stepper motor driver circuit has been designed; stepper motor is used to drivegrating mobile device to make the grating move parallelly on the guide rall, by this action gratingstripe images with different phase have been acquired to cooperate with cameras to acquire imagedata. Stepper motor driver circuit is made of chip THB7128which has the characteristic of highpower and high-subdivision and its peripheral circuit, and through the control program of FPGAstepper motor is positioned accurately.2. The module of Camera Link interface circuit has been designed to connect four cameras withsynchronous control driver.In the interface circuit, chip DS90CR288A has been chosed to receiveimage data and convert the level format of image data; chip DS90LV047A has been chosed to convertthe level format of trigger control signal from FPGA to cameras; chip DS90LV019has been chosed toconvert the level format of serial communication signal.3. The module of image storage circuit has been designed; image storage circuit is made of chipK4S561632A which is a kind of SDRAM and its peripheral circuit. The image data is transmitted tothe inner FIFO of FPGA firstly and then transmitted from the FIFO to computer.4. The module of image data communication circuit has been designed; USB2.0interface hasbeen chosed as the interface between synchronous control driver and computer to teansmit image data.Image data communication circuit is made up of chip CY7C68013which is a kind of communicationinterface chip and its peripheral circuit, in the term of software design, communication interfacecontroller program and firmware program of chip have been designed to make sure image datatransmitted accurately.In this paper, the hardware circuit design and Verilog HDL software development ofquad-nocular stereo measurement system has been completed. Main modules of synchronous controlsystem have been simulated through software Modelsim. In the experimental platform, function testhas been done to verify the feasibility and validity of synchronous control system of quad-nocularstereo measurement.