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A novel trajectory design methodology is proposed in the current work to minimize the state uncertainty in the crucial mission of spacecraft rendezvous. The trajectory is shaped under constraints utilizing a multiple-impulse approach. State uncertainty is characterized in terms of covariance, and the impulse time as the only effective parameter in uncertainty propagation is selected to minimize the trace of the covariance matrix. Furthermore, the impulse location is also adopted as the other design parameter to satisfy various translational constraints of the space mission. Efficiency and viability of the proposed idea have been investigated through some scenarios that include constraints on final time, control effort, and maximum thruster limit addition to considering safe corridors. The obtained results show that proper selection of the impulse time and impulse position fulfills a successful feasible rendezvous mission with minimum uncertainty. [ABSTRACT FROM AUTHOR]

Strain gauge balances (SGBs) are efficient and accurate means of static force measurement. However, due to their inherent elastic characteristics, they lack desired performance when used in dynamic loading conditions. In this paper, a novel technique is presented that remedies their inherent weakness in measuring dynamic periodic forces. The proposed method produces a correction factor to compensate the measured loading in dynamic situations. For this purpose, first an analytical investigation is performed to determine the structural dynamic behavior of a typical SGB system via the modal approach. This analytical investigation leads to identification of the structural interference effects that occurs on the SGB output in dynamic scenarios and renders the desired validated dynamic correction factor for periodic loading correction. The proposed methodology allows for extraction of the true SGB signal and/or loading out of the complex erroneous SGB output. As a case study, a periodic loading is measured via two different balances and the results are compared with and without taking into account the correction factor. The result of this investigation demonstrates that the introduced correction factor plays a crucial role in dynamic force estimation, especially when the loading frequency approaches the natural frequencies of the balancing system structure. [ABSTRACT FROM PUBLISHER]