Simulation And Optimization Control Of The Scissor Space Extension Arm Deployment Process

As a kind of space deployable structure, scissor space deployable mast is widely used in various kinds of spacecraft. To decrease the research cost of space deployable mast and make it expand smoothly, simulation analysis and optimal control of the deployment process of scissor space deployable mast are studied in this paper.In the simulation of the deployment process, scissor space deployable mast is considered as composed of rigid rods, then we get the simplified physical model. By using the multi-rigid-body dynamics, the deployment process model which is called the Euler- Lagrange equation is established. The equation solving method studied in this paper is the high-order variational numerical integration method and the traditional numerical method. Through the comparative analysis of the two method, we see that the high-order variational numerical integration method is more accurate and can be used in the field of aerospace. It can ensure that the simulation of deployment process has high accuracy.In the optimal control of the deployment process, the optimal control model for the deployment process of scissor space deployable mast is established. Firstly the gradient based optimization method is studied in this paper. The calculation process of the gradient is given and the problems in this kind of method are analyzed. Then the genetic algorithm which doesn't need to calculate the gradient is studied. The premature problem of genetic algorithm and the causes of the problem are analyzed. A scheme which is based on the individual similarity and used to select crossover individuals is given in this paper. In addition, a new adjustment strategy of the probability in genetic algorithm is presented.Through the performance analysis experiment, the effectiveness of the improved scheme in this paper is verified. Finally, the improved genetic algorithm is used to seek the optimal driving force. We can see from the result that the improved algorithm can effectively find out the optimal driving force and is suitable for the complex optimal control problem in aerospace field.