Passively-Safe and Robust Multi-Agent Optimal Control with Application to Distributed Space Systems

TL;DR

This paper introduces a passive safety methodology for multi-agent optimal control that ensures safety even during control failures, with applications to distributed space systems and demonstrated through experimental results.

Contribution

It presents a novel passive safety approach that simplifies safety constraints in multi-agent control, enhancing fault tolerance and computational efficiency for space applications.

Findings

Ensures safety during control failures in multi-agent systems.

Reduces computational complexity of safety constraints.

Demonstrates effectiveness in space system simulations.

Abstract

This paper presents a novel methodology to enforce motion safety guarantees even in the event of a sudden loss of control capabilities by any agent within a multi-agent system. This passive safety methodology permits the replacement of point-evaluated constraints on the trajectory following a contingency with a single function of the integration constants of the equations of motion at contingency instants. The effects of uncertainties on the trajectory are compensated for through the method of variation of parameters. This permits a reduction in the number of required constraints by one polynomial degree in the number of discrete time samples, and allows computationally efficient enforcement of passive safety within a multi-agent optimal control problem, solvable using direct methods. The main application is distributed space systems employing miniaturized low size-weight-and-power and commercial-off-the-shelf technology, which reduce mission financial costs at the expense of reliability. Experimental results for the upcoming Virtual Super-resolution Optics with Reconfigurable Swarms (VISORS) mission, as well as complementary formation-flying test cases in eccentric orbits, demonstrate the advantages of the proposed methodology in achieving fault-tolerant safety guarantees, as well as computational efficiency.