Abstract：When increasing the spacecraft agility by optimal control, risk and benefits coexist. A method was developed to assess spacecraft agility and estimate the agility enhancement. The model analyzes the conventional eigenaxis rotation and the time-optimal rotation. Then, the reorientation time was used to define an angular acceleration envelope and an equivalent agility envelope with an agility factor and an agility curve introduced to quantitatively assess the spacecraft agility. Numerical simulations validate the reliabilities of the estimates. The results are consistent with previous research and the average reorientation time is well predicted. Thus, this method is suitable for assessing spacecraft agility.
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2019, Vol. 59 
