Derek M. Surka

Multiple agent-based autonomy for satellite constellations

Multiple, highly autonomous, satellite systems are envisioned in the near future because they are capable of higher performance, lower cost, better fault tolerance, reconfigurability and upgradability. This paper presents an architecture and multi-agent design and simulation environment that will enable agent-based multi-satellite systems to fulfill their complex mission objectives, termed ObjectAgentTM. Its application is shown for a distributed aperture radar mission, although its applicability spans many types of missions. Required spacecraft functions, software agents, and multi-agent organisations are described for the radar mission, as well as their implementation. Agent-based simulations of mission case studies show the autonomous operation of the multi-agent architecture, which can then be used to build, evaluate and compare autonomous software architectures for multiple satellite systems.

The real-time ObjectAgent software architecture for distributed satellite systems

The ObjectAgent system is being developed to create an agent-based software architecture for autonomous distributed systems. Agents are used to implement all of the software functionality and communicate through simplified natural language messages. Decision-making and fault detection and recovery capabilities are built-in at all levels. During the first phase of development, ObjectAgent was prototyped in Matlab. A complete, GUI-based environment was developed for the creation, simulation, and analysis of multiagent multisatellite systems. Collision avoidance and reconfiguration simulations were performed for a cluster of four satellites. ObjectAgent is now being ported to C++ for demonstration on a real-time, distributed testbed and deployment on TechSat 21 in 2003. The present architecture runs on a PowerPC 750 running Eneas OSE operating system. A preliminary demonstration of using ObjectAgent to perform a cluster reconfiguration of three satellites was performed in November 2000.

Commanding and controlling satellite clusters

Many organizations, including the National Aeronautics and Space Administration (NASA) and the US Department of Defense, want to use constellations or fleets of autonomous spacecraft working together to accomplish complex mission objectives. At the Air Force Research Laboratorys Space Vehicles Directorate, we are developing architectures for commanding and controlling a cluster of cooperating satellites through autonomous software development for the TechSat 21 program. Large clusters of satellites flying in formation must have some level of onboard autonomy in order to: fly within specified tolerance levels; avoid collisions; address fault detection, isolation, and resolution (FDIR); share knowledge; and plan and schedule activities. Commanding and controlling a large cluster of satellites can be very burdensome for ground operators as well. The article describes efforts to address these issues through the technology development for TechSat 21.

Controlling Multiple Satellite Constellations Using the TEAMAgent System

There is an increasing desire in many organizations, including NASA, to use constellations or fleets of autonomous spacecraft working together to accomplish complex mission objectives. Coordinating the activities of all the satellites in a constellation is not a trivial task, however.

Intelligent Planning Systems for Space Resiliency

The Air Force Research Laboratory is leading research to improve the resiliency of space systems through the design of autonomous planning systems to avoid, work through, recover quickly, and minimize the effects of on-orbit events. This has involved the application of planning systems research from the Artificial Intelligence field to the unique requirements of remote systems with limited sensing and communication capabilities. Multiple planning agents and approaches are being integrated into a coherent threat response planner. This resiliency planner is being designed to interface directly with traditional flight software so that on-orbit demonstrations can be performed in the future.