Trajectory‐keeping in satellite formation flying via robust periodic learning control

Abstract

SUMMARYThis paper proposes an iterative learning control (ILC) scheme to ensure trajectory-keeping in satellite formation flying. Since satellites rotate the earth periodically, position-dependent disturbances can be considered time-periodic disturbances. This observation motivates the idea of repetitively compensating for external disturbances such as solar radiation, magnetic field, air drag, and gravity forces in an iterative, orbit-to-orbit manner. It is shown that robust ILC can be effectively utilized for satellite trajectory tracking, thus enabling time-variant formation flying between the leader-and follower-satellites. The validity of the results is illustrated through computational simulations.

Bipartite coordination problems on networks of multiple mobile agents

“…where A, B, C and D are the same matrices as defined in (17), and ξ k (t) = (D ⊗ I)η k (t) as used in (12) and (13).…”

“…Through the leader or reference designed properly in [9]- [16], the coordination of networked agents can be ensured to behave certain desired performances asymptotically with respect to time. However, these control methods may not work effectively when it comes to the class of desired coordination tasks with high-precision achieving requirements for all the time, e.g., see [17] for trajectory-keeping of formation satellites, [18] for trajectory tracking of running trains and [19] for harmonic currents compensation of power networks.…”

“…To address the high-precision achieving coordination problems in [17]- [19], iterative learning control (ILC) is found as a good approach mainly due to its ability in refining "perfect tracking" system performances over any fixed time interval (see, e.g., the surveys [20]- [22] for more details). In particular, ILC is a class of data-driven methods which play a practically important role in many industrial areas (see, e.g., [23], [24] for detailed discussions).…”

Iterative learning control with input sharing for multi-agent consensus tracking

“…many industry problems require repetitive executions and coordinations among several subsystems. For instance, from the operational point of view, it is very useful for a group of satellites orbiting the earth in formation for monitoring or positioning purpose [11]. As the satellite moving around the earth is a periodic task, the formation problem can fit perfectly in the ILC framework.…”

A switching periodic adaptive control approach for time‐varying parameters with unknown periodicity

“…These variations can exist in the system parameters [1,2], as a disturbance to the system [3][4][5] or as the tracking objective [6,7]. Classical adaptive control, which mainly focuses on the constant parametric uncertainties, cannot produce satisfying performance for periodic variations, even for the slow-varying case [8].…”