Research On Signal Processing System Of Two-dimensional Laser Displacement Sensor Based On FPGA+DSP

As a kind of Non-Contact Measurement,Two-Dimensional(2D)Laser Displacement Measurement has the characteristics of simple measurement principle,moderate measurement accuracy and fast measurement speed.It plays an increasingly important role in Industrial Production,Reverse Simulation and Aeronautical Manufacture.With the rapid development of Software Technology,in order to further improve the measurement accuracy and applicability of 2D Laser Displacement Sensor,people put forward many solution algorithms for various problems encountered in the measurement process.As the increase of algorithm complexity,the processing speed of its Signal Processing System should also be improved accordingly to meet the real-time requirements of the measurement system.In this paper,a Signal Processing System based on FPGA(Field Programmable Gate Array)and DSP(Digital Signal Processing)architecture is proposed.Based on the powerful parallel computing capability of FPGA,Light Bar Image Preprocessing and Light Bar Center Coordinate Extraction are carried out on FPGA processor.The DSP processor is responsible for converting the Light Bar Center Coordinates into the object’s displacement,and finally the Object Outline is displayed through the LCD(Liquid Crystal Display)screen.In this paper,introduce the Triangulation Measurement Principle firstly,describe the2 D Laser Displacement Sensor system model and give the mathematical formula for this system model.Based on this,designed the System Overall Structure and explained the main device models.Then introduce the System Hardware Design in detail and complete the circuit design of the Image Acquisition Card 、 Control and Processing System.The software design is divided into two parts: Image Preprocessing and Image Feature Processing.Image Preprocessing includes Light Bar Image Acquisition,Image Filtering,and Ping-Pong cache operations,before which the IIC protocol needs to be implemented to complete the image sensor initialization.Image Feature Processing includes Image Segmentation,Light Bar Center Coordinate Extraction,Data Transmission,Displacement Calculation and Object Outline Display,and the purpose of Image Feature Processing is to complete the calculation for the Light Bar Center Coordinate to the object Y and Z axis displacement.Finally,in order to verify the feasibility of the Signal Processing System,a2 D Laser Displacement Sensor debugging platform is built to measure the triangular prism,cylinder and cube respectively.The LCD screen can correctly display the object outline,which shows the correctness of the Signal Processing System.