Steve Schaffer

Peer-to-peer planning for space mission control

Planning and scheduling for space operations entails the development of applications that embed intimate domain knowledge of distinct areas of mission control, while allowing for significant collaboration among them. The separation is useful because of differences in the planning problem, solution methods, and frequencies of replanning that arise in the different disciplines. For example, planning the activities of human spaceflight crews requires some reasoning about all spacecraft resources at timescales of minutes or seconds, and is subject to considerable volatility. Detailed power planning requires managing the complex interplay of power consumption and production, involves very different classes of constraints and preferences, but once plans are generated they are relatively stable. A prototype application has been developed that separately supports Crew planning and Power planning for the International Space Station (ISS). Domain requirements have been modeled in a significant level of detail, and loosely-coupled integration has been demonstrated in a realistic scenario. The integration is enabled by implementing a generic collaboration architecture that can be used to coordinate the work of any number of planning domains. The architecture is used to integrate two different planners employing different underlying algorithms and data structures, by means of mapping the overlapping facets of the plans.

An approach to autonomous operations for remote mobile robotic exploration

This paper presents arguments for a balanced approach to modeling and reasoning in an autonomous robotic system. The framework discussed uses both declarative and procedural modeling to define the domain, rules, and constraints of the system and also balances the use of deliberative and reactive reasoning during execution. This paper also details the implementations of such an approach on two research rovers and a simulated rover all in a Mars-like environment. Intelligent decision-making capabilities are shown in the context of several unforeseen events, which require action. These events test the systems framework by requiring the system to handle uncertainty in state and resource estimations and in real-world execution. Future work, which further enhances the idea of balanced reasoning, is also discussed.

Onboard classification of hyperspectral data on the Earth Observing One mission

Remote-sensed hyperspectral data represents significant challenges in downlink due to its large data volumes. This paper describes a research program designed to process hyperspectral data products onboard spacecraft to (a) reduce data downlink volumes and (b) decrease latency to provide key data products (often by enabling use of lower data rate communications systems). We describe efforts to develop onboard processing to study volcanoes, floods, and cryosphere, using the Hyperion hyperspectral imager and onboard processing for the Earth Observing One (EO-1) mission as well as preliminary work targeting the Hyperspectral Infrared Imager (HyspIRI) mission.

Autonomous Planning and Execution for a Future Titan Aerobot

We are developing onboard planning and execution technologies to provide robust and opportunistic mission operations for a future Titan aerobot. Aerobot have the potential for collecting a vast amount of high priority science data. However, to be effective, an aerobot must address several challenges including communication constraints, extended periods without contact with Earth, uncerttain and changing environmental conditions, maneuvarability constraints and potentially short-lived science opportunities. We are developing the AerOASIS system to develop and test technology to support autonomous science operations for a future Titan Aerobot. The planning and execution component of AerOASIS is able to generate mission operations plans that achieve science and engineering objectives while respecting mission and resource constraints as well as adapt the plan to respond to new science opportunities. Our technology leverages prior work on the OASIS system for autonomous rover exploration. In this paper we describe how the OASIS planning component was adapted to address the unique challenges of a Titan Aerobot and we describe a field demonstration of the system with the JPL prototype aerobot.