Self-deployable booms are designed to fold elastically and to spontaneously deploy using structurally stored energy. Dealing with redundant vibration and oscillation produced after complete deployment is the main problem about using these structures. Also, the booms stiffness decreases after deployment so as it may returns due to a moment that applied on it. Therefore, it is necessary to design a mechanism by which the boom joint's redundant oscillations are decreased and the boom's stiffness, as well as stability, is increased. In this study, a composite deployable boom is first simulated via multibody dynamic analysis software, and then a mechanism is designed for decreasing the boom's redundant oscillations and vibrations, as well as increasing the boom's stability and stiffness. The results show that, by use of the designed mechanism for decreasing oscillation of the joints of the boom, the extra vibration of the deployed boom has been damped in much less time. Also, using this mechanism balances and decreases the applied influence and vibration on the satellite due to the boom's deployment, and consequently facilitates the quick stability of the satellite.

The performance function of many engineering structures and mechanisms is usually complex, highly nonlinear, and described in the implicit form. The reliability analysis of these structures using common methods requires high cost and time. In this paper, a new approach for reliability analysis of engineering structures and mechanisms by using the particle swarm optimization algorithm is presented. The advantages of this method in comparison with the conventional methods are its simplicity and accuracy. In addition, the limitations of the common previously presented methods are eliminated by the proposed method. This approach is based on a new redefinition of most probable point in the reliability analysis. To evaluate the performance and validity of the proposed method, some examples in the reliability analysis of various functions are employed. Finally, the superiority of the proposed method in performance and accuracy is demonstrated and compared to the conventional methods and it can be used for reliability analysis of complicated engineering structures.