Now showing items 1-20 of 37

    • Adaptive Fault Detection and Tolerance for Robots 

      Visinsky, Monica L.; Cavallaro, Joseph R.; Walker, Ian D. (1994-08-01)
      In existing robot fault detection schemes, sensed values of the joint status (position, velocity, etc.) are typically compared against expected or desired values, and if a given threshold is exceeded, a fault is inferred. ...
    • Analysis of Robots for Hazardous Environments 

      Harpel, Barbara McLaughlin; Dugan, Joanne Bechta; Walker, Ian D.; Cavallaro, Joseph R. (1997-01-01)
      Reliability analysis of fault tolerant systems often ignores the small probability that a failure might not be detected or, if detected, may not be properly handled. The probability that the failure is detected and properly ...
    • Dynamic Fault Reconfigurable Intelligent Control Architectures for Robotics 

      Cavallaro, Joseph R.; Walker, Ian D. (1993-04-01)
      In this paper we describe new progress in our development of an Intelligent Control Framework for robots which dynamically reconfigures itself to cope with faults in either sensors or joint hardware. The Framework is ...
    • A Dynamic Fault Tolerance Framework for Remote Robots 

      Visinsky, Monica L.; Cavallaro, Joseph R.; Walker, Ian D. (1995-08-01)
      Fault tolerance is increasingly important for robots, especially those in remote or hazardous environments. Robots need the ability to effectively detect and tolerate internal failures in order to continue performing their ...
    • Dynamic Senor-Based Fault Detection for Robots 

      Visinsky, Monica L.; Cavallaro, Joseph R.; Walker, Ian D. (1993-09-01)
      Fault detection and fault tolerance are increasingly important for robots in space or hazardous environments due to the dangerous and often inaccessible nature of these environs. We have previously developed algorithms to ...
    • Evaluating the reliability of prototype degradable systems 

      Leuschen, Martin L.; Walker, Ian D.; Cavallaro, Joseph R. (2001-04-01)
      The technique introduced in this paper is a new technique for analyzing fault tolerant designs under considerable uncertainty, such as seen in unique or few-of-a-kind devices in poorly known environments or pre-prototype ...
    • Experimental AR Fault Detection Methods for a Hydraulic Robot 

      Leuschen, Martin L.; Walker, Ian D.; Cavallaro, Joseph R.; Gamache, Ronald; Martin, Mike (2000-09-01)
      This paper focuses on practical use and theoretical elaboration of the analytical redundancy technique which is used to efficiently detect faults that have been determined to be mission-hazardous by previous FMECA and fault ...
    • Expert System Framework for Fault Detection and Fault Tolerance in Robotics 

      Visinsky, Monica L.; Cavallaro, Joseph R.; Walker, Ian D. (1994-01-01)
      Fault tolerance is of increasing importance for modern robots. The ability to detect and tolerate failures enables robots to effectively cope with internal failures and continue performing assigned tasks without the need ...
    • Expert System Framework for Fault Detection and Fault Tolerance in Robotics 

      Visinsky, Monica L.; Cavallaro, Joseph R.; Walker, Ian D. (1992-11-01)
      Fault tolerance is of increasing importance for modern autonomous industrial robots. The ability to detect and tolerate failures will enable robots to effectively cope with internal failures and continue performing assigned ...
    • Failure Mode Analysis for a Hazardous Waste Clean-up Manipulator 

      Walker, Ian D.; Cavallaro, Joseph R. (1996-05-01)
      This paper describes the application of Fault Tree Analysis to the design phase of a robot manipulator for hazardous waste retrieval. The robot is to be deployed in single-shell under-ground storage tanks at the US Department ...
    • Failure Mode Analysis of a Proposed Manipulator-based Hazardous Material Retrieval System 

      Cavallaro, Joseph R.; Walker, Ian D. (1997-04-01)
      Failure mode and reliability analysis is particularly important for robot manipulators to be deployed in remote environments, where inspection and repair are diffcult, and reliability is of prime importance. This is ...
    • Fault Detection and Fault Tolerance in Robotics 

      Visinsky, Monica L.; Walker, Ian D.; Cavallaro, Joseph R. (1991-07-01)
      Robots are used in inaccessible or hazardous environments in order to alleviate some of the time, cost and risk involved in preparing men to endure these conditions. In order to perform their expected tasks, the robots ...
    • Fault Residual Generation via Nonlinear Analytical Redundancy 

      Leuschen, Martin L.; Walker, Ian D.; Cavallaro, Joseph R. (2005-05-01)
      Fault detection is critical in many applications, and analytical redundancy (AR) has been the key underlying tool for many approaches to fault detection. However, the conventional AR approach is formally limited to linear ...
    • Fault Tolerant Algorithms and Architectures for Robotics 

      Hamilton, D. L.; Visinsky, Monica L.; Bennett, J. K.; Cavallaro, Joseph R.; Walker, Ian D. (1994-04-01)
      As robot tasks in space, nuclear, and medical environments become more widespread, the issues of reliability and safety for robots are becoming more critical. Attempts to address these issues have resulted in a a recent ...
    • Investigation of Reliability of Hydraulic Robots for Hazardous Environments Using Analytic Redundancy 

      Leuschen, Martin L.; Walker, Ian D.; Cavallaro, Joseph R. (1999-01-01)
      The Rosie mobile worksystem is a robot that is on the cutting edge of hazardous environment robotics. It is a heavy-duty hydraulic robot designed for nuclear reactor decontamination and dismantlement. The robot consists ...
    • Keeping the Analog Genie in the Bottle: A Case for Digital Robots 

      Walker, Ian D.; Cavallaro, Joseph R.; Leuschen, Martin L. (1999-05-01)
      In this paper, we consider the case for adopting a truly 'digital' type of robot, which would evolve between a discrete and finite set of states. We adopt the point of view that the advantages of traditional robotic evolution ...
    • Layered Dynamic Fault Detection and Tolerance for Robots 

      Visinsky, Monica L.; Walker, Ian D.; Cavallaro, Joseph R. (1993-05-01)
      Fault tolerance is increasingly important for space and hazardous environment robotics. Robots need to quickly detect and tolerate internal failures in order to continue performing their tasks without the need for immediate ...
    • Monitoring and Diagnostics for a Hydraulic Robot in Hazardous Environments 

      Leuschen, Martin L.; Cavallaro, Joseph R.; Walker, Ian D. (1999-04-01)
      Hazardous environments are an important application of modern robotic techniques. However, failures can be quite serious in such environments, especially if they trap the robot within or damage containment efforts. Thus ...
    • New Dynamic Model-Based Fault Detection Thresholds for Robot Manipulators 

      Visinsky, Monica L.; Walker, Ian D.; Cavallaro, Joseph R. (1994-05-01)
      Autonomous robotic fault detection is becoming increasingly important as robots are used in more inaccessible and hazardous environments. Detection algorithms, however, are adversely effected by the model simplification, ...
    • New Real-Time Robot Motion Algorithms Using Parallel VLSI Architectures 

      Deo, Arati S.; Cavallaro, Joseph R.; Walker, Ian D. (1991-03-01)
      Real time robot control presents a major numerical challenge. The inverse kinematics problem of determining joint motion for a specified end effector trajectory is formulated as a damped least-squares problem which balances ...