Electromechanical Actuator (EMA) as an important part of the missile control systems, whose performance plays a great influence on the dynamic quality of the missile. This paper studied the present situation in this field, proposed a new four simultaneous axes Electromechanical Actuator based on ball screw and spatial linkage combined, and researched the effect of the dynamic performance of the electromechanical actuator in detail caused by the motion pairs with clearances and flexible bodies. It proved that the program is worked by simulation analysis and experimental comparison. This paper first determined the overall scheme of the electromechanical actuator, including the transmission scheme with ball screws and spatial linkage combining, and the double closed loop control scheme with speed and position. It selected a brushless DC motor as the power input, and the first reducer is ball screw, the second one is four RSSR spatial linkages combined. It researched the influence of ratio and moment of inertia to the MEA. It selected the total transmission ratio of 84. To increase the synchronization of four output shaft, kinematic research and the parameter optimization was taken out in four RSSR spatial linkage combined mechanism. The result is the angle error between the four output shaft ranges -0.143 ° to 0.210 °. Clearance and flexibility are the key issues that affect the dynamic performance of mechanical systems. This paper mainly studied the effect of these elements on the dynamic performance. First a non-linear spring-damper contact dynamic force model based on Hertz contact theory was established to describe the contact-impact force, called Lankarani and Nikravesh model. Then study the influence of clearances to the impact speed and contact force. The single and multiple clearances and flex bodies of nonlinear factors on the dynamic performance of the EMA transmission system were researched. Studies have shown that: contact force is several times than ideal force, and the speed and acceleration generated huge fluctuations; when a branch in the system containing two ball motion pairs with radius clearance 0.01-0.03mm, single output shaft position error is ±0.08o, compared with ideal motion pair. When considering the weak aspects, like circular shaft, linkages, etc. The output shaft position error to ±0.081o; through the analysis of the system frequency and experimental test, it proved that system resonant frequency above 100Hz and met the system requirements. Finally, a co-simulation was established with the flexible multi-body EMA transmission system with clearances, based on ADAMS/Control and Simulink. A simulation block diagram of double closed loop with position and speed was built, debugged controller parameters and executed simulation test, and the result was met the system target. Finally, semi-physical simulation platform of EMA transmission system was established based on Matlab/xPC environment. The result of the test showed that, the EMA output torque is 10Nm; the maximum rudder angle is ±20o; the maximum rudder angle speed is 250o/s; and bandwidth is 23.17Hz. Each of the performance were met the requirements. Through the study of the new EMA show that, the ball screw and RSSR spatial linkage combined EMA is worked well. The work of the thesis provided a guiding role in the theory and engineering applications on the new electromechanical actuator research work.
The new generation of optical remote sensing satellite shows the development trend of light and small-sized, low cost, high functional density, agile and fast maneuverability. It pays attention to the fast, flexible and efficient target imaging, and the satellite attitude control frequency is high. After agile mobile, it can quickly stabilize and perform tasks. It is foreseeable that the future "agile remote sensing satellite" will show an explosive growth. The baseband of the traditional solar panel connection is low in basic frequency and poor in stiffness. In rapid maneuver, its rigid flexible coupling vibration on the satellite, can directly affect the imaging quality of the camera and take a long time to restore stability, reduce the satellite pointing accuracy, especially for the attitude control of high frequency agile small satellite, when developed similar "fundamental windsurfing and attitude control frequency resonance coupling is serious. The high stiffness of the stretching and supporting technology is an advanced technology of agile maneuver, rapid and stable current to realize the satellite and multi mode imaging function, with panels high fundamental frequency, damping ratio and other advantages, in the agile small satellite has broad application prospects of remote sensing and other fields.Combined with the engineering practice of a certain type of agile satellite remote sensing, the optimum design method of dynamic analysis, simulation and experimental verification of combining the proposed innovative deployment and support technology based on cobalt based high elastic alloy tape springs high rigidity solar panels, effectively solve the problems of the prior art. The research of this paper mainly includes the following aspects:Firstly, the characteristics of satellite related technology at home and abroad are summarized and analyzed, and the design method of deployment and support