The Imaging System And Application Based On TOF

Compared with 2D imagining,3D imagining contains more information and has irreplaceable effect in many fields.3D imagining is indisputably important for artificial intelligence,monitor,biomedical engineering.Therefore,a range camera with high accuracy is necessary.This thesis analyse the way that the range camera worked and compared some popular range cameras that work with different principle.Then we selected time of flight(TOF)and designed a range camera based on this principle.A 3D imaging camera working with TOF principle is introduced.At first,the four Phase shift algorithm is introduced,then index of camera is set.The main research of this thesis is as follows:1.The influence of the distance between square LED arrays and the radius of circular LED arrays on the illumination intensity of a given illumination surface is discussed.By analyzing the illumination intensity of the LED,the illumination intensity of the tow arrays is deduced.The optimal parameters are calculated by Sparrow's rule.The fitting functions of the optimal parameters of the two arrays are obtained and verified by simulation.Finally,select a circular LED array combining the selected LED parameters.2.Selection of components and hardware design of the whole system are completed.The circuit of each hardware module is designed,The hardware part includes power management part,main controller part,level conversion module and data acquisition hardware module.The design of PCB board is carried out.Finally,the normal function of the hardware board is verified by testing.3.The program is designed.The program mainly includes upper computer program,lower computer program and real-time operating system based on Cortex-M4 core.The upper computer program is designed with MATLAB GUI.The communication protocol between upper computer and lower computer is defined.The lower computer software is designed based on the real-time operating system designed in this paper,The communication protocol between tasks is defined.The system is calibrated and the parameter matrix is obtained.4.The correctness of the calibration results is verified by testing.The feasibility of adjusting integration time according to the size of raw data to improve measurement accuracy is illustrated by discussing the working principle of the sensor and the algorithm of four-part phase shift.The correctness of this method is proved by test.The B-spline Curves is used to improve the accuracy and the stability of system.The test result showed that the accuracy of this range data acquisition is 1 cm,The frame rate of data acquisition is over 20 fps,It meets the design target.