Active vibration control of underactuated free-floating spacecraft via a performance enhanced way

This paper investigates an enhanced prescribed performance control approach for the postcapture active vibration suppression of the underactuated free-floating spacecraft via only using the output information. First, an enhanced performance function is developed to quantitatively characterize the transient and steady-state vibration responses. Then, based on the performance function, an output-feedback prescribed performance controller along with an adaptive nonlinear filter is devised to eliminate the vibration within arbitrarily specified time. Compared with the existing works, the primary advantage is that the convergence time of the vibration system can be offline preassigned arbitrarily by the users. In the meanwhile, the proposed control scheme can be directly extended to a class of nonstrict feedback systems. Finally, applications to the underactuated free-floating spacecraft are employed to validate the effectiveness of the proposed enhanced prescribed performance control approach.