Control reconfiguration

About: Control reconfiguration is a research topic. Over the lifetime, 22423 publications have been published within this topic receiving 334217 citations.

Nonlinear Reconfiguring Flight Control Based on Online Physical Model Identification

Abstract: This paper presents a study on fault tolerant flight control of a benchmark aircraft model. Reconfiguring control is implemented by making use of adaptive nonlinear dynamic inversion for manual and autopilot control. The weakness of classical nonlinear dynamic inversion, its sensitivity to modeling errors, is circumvented here by making use of a real-time identified physical model of the damaged aircraft. With help of the Boeing 747 benchmark simulation model, including the realistic component as well as the structural failure modes, it is possible to analyze the damage accommodation capabilities of the considered approach. In failure conditions, the damaged aircraft model is identified by the so-called two-step method in real time and this model is applied subsequently to the model-based adaptive nonlinear dynamic inversion routine in a modular structure, which allows flight control reconfigurations online. After discussing the modular adaptive controller setup, reconfiguration test results are shown for damaged aircraft models using a desktop computer as well as the moving base Simulation, Motion, and Navigation Research Flight Simulator of Delft University. These results indicate satisfactory failure handling capabilities of this fault tolerant control setup, for component as well as structural failures.

Fault Detection and Fault Tolerant Operation of a Five Phase PM Motor Drive Using Adaptive Model Identification Approach

Abstract: Nowadays, the use of multiphase fault tolerant permanent magnet (PM) machines is a suitable solution for increasing the reliability of high-performance motion control applications. This solution requires fault detection, isolation, and control adaptation. For this reason, a new open switch fault detection scheme in voltage-source inverter supplying a PM motor is presented in this paper. The detection method is based on model identification of the motor phase currents. The detection scheme is fast, robust, general, and capable of detecting multiple faults. The control algorithm, detection method, isolation, and reconfiguration strategies are discussed. After that, the proposed method is implemented in the fault tolerant control of a five-phase brushless direct current (BLDC) motor drive. Simulation results in MATLAB/Simulink are shown to demonstrate the effectiveness of the proposed detection technique. Experimental results on a five-phase fault tolerant BLDC motor validate the theoretical developments.

Run-time reconfiguration method for programmable units

Abstract: A method of run-time reconfiguration of a programmable unit is provided, the programmable unit including a plurality of reconfigurable function cells in a multidimensional arrangement. An event is detected. The source of the detected event is determined, and an address of an entry in a jump table is calculated as a function of the source of the event, the entry storing a memory address of a configuration for a reconfigurable function cell. The entry is retrieved and a state of a corresponding reconfigurable cell is determined. If the reconfigurable cell is in a reconfiguration state, the reconfigurable cell is reconfigured as a function of the configuration data. If the reconfigurable cell is not in a reconfiguration state, the configuration data is stored in a FIFO.

Performance and fault-tolerance of neural networks for optimization

Abstract: The fault-tolerance characteristics of time-continuous, recurrent artificial neural networks (ANNs) that can be used to solve optimization problems are investigated. The performance of these networks is illustrated by using well-known model problems like the traveling salesman problem and the assignment problem. The ANNs are then subjected to up to 13 simultaneous stuck-at-1 or stuck-at-0 faults for network sizes of up to 900 neurons. The effect of these faults on the performance is demonstrated, and the cause for the observed fault-tolerance is discussed. An application is presented in which a network performs a critical task for a real-time distributed processing system by generating new task allocations during the reconfiguration of the system. The performance degradation of the ANN under the presence of faults is investigated by large-scale simulations and the potential benefits of delegating a critical task to a fault-tolerant network are discussed. >

Planning quasi-static fingertip manipulations for reconfiguring objects

Abstract: We address the global motion planning aspects of dexterous manipulation by a multifingered robotic hand. The specific task we address is: starting from a given initial grasp of a three-dimensional (3-D) object O, find feasible quasistatic trajectories (rolling/sliding motions and forces) for the fingertips to move O to a desired final configuration. We call this the reconfiguration problem. Our planner is based on a two-level algorithm combining a graph search on the configuration space of the object and a local planner that solves for instantaneous quasistatic motions of the entire manipulation system. The planner is used for simulating several complex reconfiguration tasks for smooth objects demonstrating the promise of our approach.