Performance Analysis And Optimization Of Radar Lifting Mechanism

This paper is devoted to a folding radar antenna lifting mechanism based on the coordinated driving of multi-cylinder of space connecting rod.In practice,the antenna lifting process not only requires fast and stability,but also requires strong adaptability and easy control.However,the lifting mechanism based on the series-parallel mechanism has a complicated configuration and a high degree of coupling.It's a multi-degree-of-freedom,multi-variable,nonlinear,multi-parameter coupling system.The law of the lifting mechanism's motion is very complicated.It's impossible to determine the position and posture of the radar antenna seat or the force of the rod during the movement by experience,intuition or simple calculation.At the same time,its motion control is also a difficult point.If each branch is treated as a completely independent subsystem and controlled by some conventional methods,it will be difficult to obtain satisfactory control effects in actual operation.Because the degree of coupling between subsystems is high and mutual influence is large,both of which often lead to contradictory requirements.Therefore,it is urgent to systematically solve the problems of the kinematics,dynamics and control strategies of the lifting mechanism,and provide design basis for the engineering realization of the lifting mechanism.Based on the above situations,this paper conducts research on kinematics,dynamics and control strategies for this mechanism,and proposes research programs and technical routes for kinematics and dynamics analysis and control strategy design.First,the antenna lifting mechanism's degree freedom of motion is demonstrated according to the method of spatial organization analysis.The spiral theory is used to calculate the freedom of motion of the mechanism in the four processes.The result shows that the mechanism can achieve the design motion pattern and the movement ability can meet the requirements by selecting the appropriate motion connection pair.Second,the kinematics model of the lifting mechanism is established by the space vector method.the stroke of each drive cylinder is calculate according to the kinematics model and the important motion pairs are verify to prove the correctness of the lift mechanism in the theory of kinematics.Then,the dynamics simulation and rigid-flexible coupling calculation of the lifting mechanism are completed in the ADAMS.The force condition of the cylinder is improved according to the calculation results.At the same time,the rigid-flexible coupling dynamics model of the lifting mechanism is also established and the flexible body is optimized by scale according to the calculated stress condition.Finally,the control law of the radar antenna lifting mechanism is designed and simulated,and the open loop control and closed loop control results in the four motion steps are compared.Due to the inaccuracy of the model measurement,the orientation angle of the platform on the radar antenna cannot meet the expected requirements in the open loop control.Through the closed-loop control,the platform orientation angle on the radar antenna meets the design requirements.