Space nets is one of most promising conceptions that designed for the space debris removal. A critical issue in the design and analysis of space net system is the deployment modeling technology. The dynamic behavior of space net system in different ejection modes is investigated based on finite segment approach. The simulation results show that the model and the evaluation index developed in this paper provide a valid method to evaluate the deployment property of different ejection modes.

A multiobjective optimization based vibration isolator design for space application is described. It is common to use passive isolator and isolate the platform noise in space applications. The design of a passive isolator involves a trade-off between the resonant peak reduction and the high frequency attenuation. The equation of motion and transfer function model for single-stage and two-stage connector model is derived by using basic principle. The multiobjective optimization model is proposed, where the design variables are the damping coefficients and stiffness coefficients, the objective functions are the resonant peak reduction and the high frequency attenuation, and the constraints are the natural frequency of the connector. The multiobjective optimization problems for the design of the passive isolator are solved by using the multiobjective evolutionary algorithm based on decomposition (MOEA/D). The Pareto front obtained can provide multiple candidate solutions for the designer. The method is effective for the design process of the passive isolator.

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The machine-part cell formation is a NP- complete combinational optimization problem. Past research has shown that although the genetic algorithm (GA) can get high quality solutions, special selection strategy, crossover and mutation operators as well as the parameters must be defined previously to solve the problem efficiently and flexibly. In this paper, an improved permutation code PBIL is adopted to solve the machine-part cell formation problem. Simulation results on five well known problems show that the PBIL can get satisfied solutions more simply and efficiently.

A framework has been developed to identify control-structure interaction design of flexible space structures that are Pareto optimal with respect to multiple conflicting objectives. The objectives and constraints of multiobjective optimization problem are derived from structure and control performances. The equation of motion of the flexible space structure are based on Lagrange’s equation. Multiobjective evolutionary algorithm based on decomposition (MOEA/D) is employed for optimization. This framework has been applied to a controlled idealized rotating structure to quantify tradeoffs in control-strcutrue design. The control-strcutrue design is optimized based on two conflicting objectives with minimize total mass and minimize control cost using MOEA/D. To solve the equality constraint of the above problem, an improvement is proposed in the implementation of MOEA/D. The improvement is based on the modification of new solution on each step of evolution. The numerical results obtained suggest that the MOEA/D and its improvement have the potential of practical applicability.