Adjustable Autonomy Testbed

The Adjustable Autonomy Testbed (AAT) is a simulation-based testbed located in the Intelligent Systems Laboratory in the Automation, Robotics and Simulation Division at NASA Johnson Space Center. The purpose of the testbed is to support evaluation and validation of prototypes of adjustable autonomous agent software for control and fault management for complex systems. The AA T project has developed prototype adjustable autonomous agent software and human interfaces for cooperative fault management. This software builds on current autonomous agent technology by altering the architecture, components and interfaces for effective teamwork between autonomous systems and human experts. Autonomous agents include a planner, flexible executive, low level control and deductive model-based fault isolation. Adjustable autonomy is intended to increase the flexibility and effectiveness of fault management with an autonomous system. The test domain for this work is control of advanced life support systems for habitats for planetary exploration. The CONFIG hybrid discrete event simulation environment provides flexible and dynamically reconfigurable models of the behavior of components and fluids in the life support systems. Both discrete event and continuous (discrete time) simulation are supported, and flows and pressures are computed globally. This provides fast dynamic simulations of interacting hardware systems in closed loops that can be reconfigured during operations scenarios, producing complex cascading effects of operations and failures. Current object-oriented model libraries support modeling of fluid systems, and models have been developed of physico-chemical and biological subsystems for processing advanced life support gases. In FY01, water recovery system models will be developed

Advanced transport operating system software upgrade: Flight management/flight controls software description

The Flight Management/Flight Controls (FM/FC) software for the Norden 2 (PDP-11/70M) computer installed on the NASA 737 aircraft is described. The software computes the navigation position estimates, guidance commands, those commands to be issued to the control surfaces to direct the aircraft in flight based on the modes selected on the Advanced Guidance Control System (AGSC) mode panel, and the flight path selected via the Navigation Control/Display Unit (NCDU)

Human-robot Interaction For Multi-robot Systems

Designing an effective human-robot interaction paradigm is particularly important for complex tasks such as multi-robot manipulation that require the human and robot to work together in a tightly coupled fashion. Although increasing the number of robots can expand the area that the robots can cover within a bounded period of time, a poor human-robot interface will ultimately compromise the performance of the team of robots. However, introducing a human operator to the team of robots, does not automatically improve performance due to the difficulty of teleoperating mobile robots with manipulators. The human operator’s concentration is divided not only among multiple robots but also between controlling each robot’s base and arm. This complexity substantially increases the potential neglect time, since the operator’s inability to effectively attend to each robot during a critical phase of the task leads to a significant degradation in task performance. There are several proven paradigms for increasing the efficacy of human-robot interaction: 1) multimodal interfaces in which the user controls the robots using voice and gesture; 2) configurable interfaces which allow the user to create new commands by demonstrating them; 3) adaptive interfaces which reduce the operator’s workload as necessary through increasing robot autonomy. This dissertation presents an evaluation of the relative benefits of different types of user interfaces for multi-robot systems composed of robots with wheeled bases and three degree of freedom arms. It describes a design for constructing low-cost multi-robot manipulation systems from off the shelf parts. User expertise was measured along three axes (navigation, manipulation, and coordination), and participants who performed above threshold on two out of three dimensions on a calibration task were rated as expert. Our experiments reveal that the relative expertise of the user was the key determinant of the best performing interface paradigm for that user, indicating that good user modiii eling is essential for designing a human-robot interaction system that will be used for an extended period of time. The contributions of the dissertation include: 1) a model for detecting operator distraction from robot motion trajectories; 2) adjustable autonomy paradigms for reducing operator workload; 3) a method for creating coordinated multi-robot behaviors from demonstrations with a single robot; 4) a user modeling approach for identifying expert-novice differences from short teleoperation traces

Authority management in human-robot systems

In the context of missions accomplished jointly by an artifical agent and a human agent, we focus on a controller of the authority dynamics based on a dependence graph of resources that can be controlled by both agents. The controller is designed to adapt the behaviours of the artificial agent or of the human agent in case of an authority conflict occurring on these resources. The relative authority of two agents regarding the control of a resource is defined so as the authority conflict, which appears relevant to trigger authority reallocation between agents as shown by a first experiment. Finally a second experiment shows that beyond the modification of the artificial agent's behaviour, it is also possible to adapt the human operator's behaviour in order to solve such a conflict

Authority sharing in human-robot systems

In the context of missions accomplished jointly by an artifi cal agent and a human agent, we focus on a controller of the authority dynamics based on a dependence graph of resources that can be controlled by both agents. The controller is designed to adapt the behaviours of the artifi cial agent or of the human agent in case of an authority conflict occurring on these resources. The relative authority of two agents regarding the control of a resource is de fined so as the authority conflict, which appears relevant to trigger authority reallocation between agents as shown by a fi rst experiment. Finally a second experiment shows that beyond the modifi cation of the arti ficial agent's behaviour, it is also possible to adapt the human operator's behaviour in order to solve such a conflict

Authority Management and Conflict Solving in Human-Machine Systems

This paper focuses on vehicle-embedded decision autonomy and the human operator’s role in so-called autonomous systems. Autonomy control and authority sharing are discussed, and the possible effects of authority conflicts on the human operator’s cognition and situation awareness are highlighted. As an illustration, an experiment conducted at ISAE (the French Aeronautical and Space Institute) shows that the occurrence of a conflict leads to a perseveration behavior and attentional tunneling of the operator. Formal methods are discussed to infer such attentional impairment from the monitoring of physiological and behavioral measures and some results are given