Fault Detection Solution Research Articles

Automatic Detection of Previously-Unseen Application States for Deployment Environment Testing and Analysis.

For large, complex software systems, it is typically impossible in terms of time and cost to reliably test the application in all possible execution states and configurations before releasing it into production. One proposed way of addressing this problem has been to continue testing and analysis of the application in the field, after it has been deployed. A practical limitation of many such automated approaches is the potentially high performance overhead incurred by the necessary instrumentation. However, it may be possible to reduce this overhead by selecting test cases and performing analysis only in previously-unseen application states, thus reducing the number of redundant tests and analyses that are run. Solutions for fault detection, model checking, security testing, and fault localization in deployed software may all benefit from a technique that ignores application states that have already been tested or explored.In this paper, we present a solution that ensures that deployment environment tests are only executed in states that the application has not previously encountered. In addition to discussing our implementation, we present the results of an empirical study that demonstrates its effectiveness, and explain how the new approach can be generalized to assist other automated testing and analysis techniques intended for the deployment environment.

A representation for coordination fault detection in large-scale multi-agent systems

Teamwork requires that team members coordinate their actions. The representation of the coordination is a key requirement since it influences the complexity and flexibility of reasoning team-members. One aspect of this requirement is detecting coordination faults as a result of intermittent failures of sensors, communication failures, etc. Detection of such faults, based on observations of the behavior of agents, is of prime importance. Though different solutions have been presented thus far, none has presented a comprehensive and efficient resolution for large-scale teams. This paper presents a formal approach to representing multi-agent coordination, and multi-agent observations, using matrix structures. This representation facilitates easy representation of coordination requirements, modularity, flexibility and reuse of existing systems. Based on this representation, we present a novel solution for fault-detection that is both generic and efficient for large-scale teams. We demonstrate the modularity of the representation by presenting a reuse of existing systems and by importing other models (e.g. hierarchical systems) into the new representation. Finally, we extend the representation to support dynamical aspects of complex systems.

Development of a Test Facility for Brushless-DC Thrusters

Remotely operated vehicles [ROVs] are complex mechatronic systems used in a number of submarine applications. The high cost associated with deep-water operation, and potential environmental sensitivity of the tasks on which ROVs may be employed are such that failures must be minimised. When problems do occur these must be handled, allowing the ROV to continue to operate, such that the operator can complete, or make safe his task, and recover the vehicle. To achieve this the presence of a fault must be noted, and appropriate action taken. It is proposed that a combination of global and distributed detection techniques provides the most satisfactory fault detection solution.

Development of a Fault Handling System for Remotely Operated Vehicles

Remotely operated vehicles [ROVs] are complex mechatronic systems used in a number of submarine applications. The high cost associated with deep-water operation, and potential environmental sensitivity of the tasks on which ROVs may be employed are such that failures must be minimised. When problems do occur these must be handled, allowing the ROV to continue to operate, such that the operator can complete, or make safe his task, and recover the vehicle. To achieve this the presence of a fault must be noted, and appropriate action taken. It is proposed that a combination of global and distributed detection techniques provides the most satisfactory fault detection solution.