Design And Implementation Of A Ground Measurement And Control System For The Huge Deployable Mechanism Of The Satellite

A high resolution optical satellite uses space-deployable optical imaging system which can fold the primary mirror at the launching time and deploy the primary mirror on the orbit by deployable mechanisms,make it possible to realize high resolution optical imaging satellite with large caliber and light quality.As an important part of the space deployable optical imaging system,the performance level of the deployable mechanism,such as the stability of the deployment process,the accuracy of the deployment position and the reliability of the whole organization,determines the successful realization of this new space deployable optical imaging system.Therefore,it is necessary to carry out a large number of ground tests on the deployable mechanism to verify the rationality of its mechanism design and the reliability of the performance,so as to eliminate the uncertainty and design risk of the technical scheme in the initial design stage of the large scale deployable mechanisms and provide effective test data? technical preparation and design basis for the final design and development.In order to solve the above requirements,the paper carefully analyzes the deployable motion process of the primary and truss mechanisms on the optical satellite and the measuring and controlling function of the ground deployment test,and fully understands the control technology of the spatial structure deploying process at home and abroad,analyzes the advantages and disadvantages of the ground deployment test equipment.On the basis of this,the overall design scheme of the ground test and control system is put forward to carry out the process control,the multi-motor cooperative control,the motion control of the stepping motor under various expansion modes,and the monitoring of the condition of the deployable device.The hardware platform of the ground measurement and control system which is used for the large deployable mechanisms of the satellite is composed of PC/104 industrial computer,bottom measurement and control system,signal processing circuit and power control system.The bottom measurement and control system uses STM32 + MCX514 architecture,through using photoelectric encoder,micro switch,Hall sensor,AD acquisition board to design measurement and control circuit to achieve precise control and real-time state monitoring of 27 stepper motor in the optical satellite primary mirror and truss;at the same time,through the design of multi-motor collaborative control algorithm to meet the system real-time?error control?different modes of motion under multiple motor work requirements.The ground measurement and control system uses Visual Studio as the software development platform,adopts the high efficiency C ++ to carry on the development of the host computer software,and applies the modular and the extensible development method to design and complete the software overall frame ?the user interaction interface and each function module.Through the host computer software and with the underlying hardware system can realize the deployable mode,the motor running parameter setting and the real-time monitoring of the state parameters of the motor,so as to realize the automatic test and control of the satellite ground test.Finally,after many times system joint debugging and deployment test,the analysis of the experimental results shows that the ground measurement and control system satisfies the functional requirements of the task and the hardware and software interface matches.The accuracy of the end control in the truss group is less than 1.5 degrees each 360 degrees,the odd group and even group of the primary mirror mechanism satisfies the dynamic following requirements.The system can complete the ground deployment test of the large scale deployment mechanism of the satellite,the running state is stable,the system performance is complete,and finally passed the acceptance of the institute,and the project delivery is completed.