Automatic Driven Design And Achievement Of Manually Lens On High-Speed Photography

In the design phase of spacecraft,for checking design or obtaining the key data which is required,the ground tests and the simulation of the important processes of the spacecraft during the flight are needed.Currently,the high-speed cameras we used are produced by American company VRI,and these cameras use NIKKOR photography lenses.Since the cameras do not have the ability to drive the lenses,the manually focus is the only way to make them work.To solve the above problems,it is necessary to install an electric drive unit for manually adjustment lens,so it can work in the special environment by autofocus drive,which will simplify the work session when the conditions permit,and improve the work efficiency.In this paper,installing the motor-focusing-driving means for the manually focus lens of high-speed camera is the study.Firstly,studied the autofocus technology,motor control technology,angular displacement measurement techniques,PID Control and Fuzzy PID Algorithms,PID control system based on BP neural network and so on.And adopt variable step size rough sweep,minimum step sweeping strategy,optimizing traditional mountain climbing algorithms.Then,proposed the hardware design of the control system based on the FPGA microcontroller controller.On the basis of these,make detailed designs of mechanical design module,temperature acquisition module,ultrasonic ranging module,motor control and angle measurement sub-module,and introduced the core workflow and software of the modules in details.Finally,debug the entire system by three operating modes of single,continuous autofocus and manual electric focus adjustment,and it achieves the key steps from the distance measure to the focus drive.And implement the feedback by measuring the angle,forming a complete closed-loop control system design.Experiments show that it is controllable and operability to install an electric drive control on the high-speed camera manual lens to achieve autofocus of lens.Control system conform the requirements of the actual test environments,and achieve the desired effect.