Lag of flexible multi-body system of mini-radar

The multi-body dynamics simulation is done on the reflector servo system of a mini-radar system by using MSC Adams and MSC Nastran,in which the key part that affects the mini-radar's precision is treated as flexible body,and into which the proper constraints and movements are added according to actual case.The purpose is studying how the lag angle between electronic shaft and encoder shaft is affected under the effect of sine angular displacement motion function and trapezoid angular velocity motion function.The study shows:there is lag between the first electronic shaft and the first encoder shaft due to vibration of flexible bodies;the maximum lag angle is related to the periods and amplitude of motion function and presents nonlinear rule;the lag angle generated by trapezoid angular velocity motion function is distinctly less than that of sine angular displacement motion function when the periods and amplitude of them are same;trapezoid angular velocity motion function can raise harmonic disturbance,vibration of multi-mode and so on,because its frequency of accelerated,uniform and decelerated motion are not same.