Diagnosis for Control and Decision Support for Autonomous Vehicles

Abstract

Abstract. Diagnosis and, when possible, prognosis of faults are essential for safe and reliable operation. The area of fault diagnosis has emerged over three decades. The majority of studies are related to linear systems but real-life systems are complex and nonlinear. The development of methodologies coping with complex and nonlinear systems have matured and even though there are many unsolved problems, methodology and associated tools have become available in the form of theory and software for design. Genuine industrial cases have also become available. Analysis of system topology, referred to as structural analysis, has proven to be unique and simple in use and a recent extension to active structural techniques have made fault isolation possible in a wide range of systems. Following residual generation using these topology-based methods, deterministic and statistical change detection has proven very useful for online prognosis and diagnosis. For complex systems, results from nonGaussian detection theory have been employed with convincing results. The chapter presents the theoretical foundation for design methodologies that now appear as enabling technology for a new area of design of systems that are reliable in practise. Yet they are also affordable due to the use of fault-tolerant philosophies and tools that make engineering efforts minimal for their implementation. The chapter includes examples for an autonomous aircraft and a baling system for agriculture to illustrate the generic design procedures and real life results.

On Cost‐effective Reuse of Components in the Design of Complex Reconfigurable Systems

“…While many works have concentrated on analysing the influence of homogeneous redundancies, approaches focusing on the evaluation of heterogeneous redundancies are scarce . Heterogeneous redundancies can take many forms: design diversity, analytical redundancies or redundancies arising from overlapped system functions …”

“…In our approach, we focus on identifying and exploiting implicit redundancy that may exist in an application. Detailed knowledge and mathematical formulation of the system is typically needed to obtain analytical redundancy relations . However, the complexity of the mathematical formulation increases with the system size, and this has led us to adopt a function‐based viewpoint that uses qualitative attributes (see also Subsection 5.2).…”

“…There are several approaches in the diagnostics and fault‐tolerant control community focused on identifying analytic redundancies systematically . A number of approaches in this area evaluate if it is possible to provide the same service with a combination of remaining sensors, that is, if there exists an alternative analytic equation, which uses a different set of variables (resources) to provide the same service.…”

Application of the D3H2 Methodology for the Cost-Effective Design of Dependable Systems

“…Heterogeneous redundancies can take many forms: design diversity [10], analytical redundancies [11], or redundancies arising from overlapped system functions [3]. All these approaches share a common design goal: the reuse of system components to provide a compatible functionality.…”

“…In our approach, we identify and exploit implicit diversity which may exist in an application to provide improved fault tolerance and reduce costs. Detailed knowledge and mathematical formulation of the system is needed to get analytical redundancy relations [11]. However, the complexity of the mathematical formulation increases with the system size, and this has led us us to adopt a function-based viewpoint with qualitative attributes, instead of a formal mathematical specification approach (see also Subsection 3.2).…”