Erik Frisk

Sensor placement for maximum fault isolability (2009)

Erik Frisk, Mattias Krys

An algorithm is developed for computing which sensors to add to obtain maximum fault detectability and fault isolability. The method is based on only the structural information in a model which means...

Contents (2009)

Erik Frisk, Mattias Nyberg

This document is a demonstration document, prepared for PolyX Ltd., demonstrating the use of the Polynomial Toolbox for Matlab when designing residual generators for fault diagnosis. A brief...

FORMULATION (2009)

Erik Frisk, Mattias Krys

Abstract: On-Board Diagnostics (OBD) regulations require that the fuel system in personal vehicles must be supervised for leakages. Legislative requirement on the smallest leakage size that has to be...

On Threshold Optimization in Fault Tolerant Systems ⋆ (2009)

Fredrik Gustafsson, Erik Frisk, Mattias Krys, Lars Nielsen

Abstract: Fault tolerant systems are considered, where a nominal system is monitored by a fault detection algorithm, and the nominal system is switched to a backup system in case of a detected fault....

DIAGNOSIS OF EVAPORATIVE LEAKS AND SENSOR FAULTS IN A VEHICLE FUEL SYSTEM (2009)

Ingemar Andersson, Erik Frisk

Abstract: This paper describes a vacuum-decay based evaporative leak detection procedure for vehicle fuel systems. A physical model for an evaporative system is proposed containing parts for fuel...

Observer Design and Model Augmentation for Bias Compensation Applied to an Engine (2009)

Erik Höckerdal, Erik Frisk, Lars Eriksson

Abstract: A systematic design method for reducing bias in observers is developed. The method utilizes an observable default model of the system together with measurement data from the real system and...

LOWERING ORDERS OF DERIVATIVES IN NON-LINEAR CONSISTENCY RELATIONS- THEORY AND SIMULATION EXAMPLES (2009)

Erik Frisk

Abstract. Consistency relations are often used to design residual generators based on non-linear process models. A main difficulty is that they generally include time differentiated versions of known...

FORMULATION (2009)

Erik Frisk

Abstract: In this paper we consider design of observers for non-linear models containing both dynamic and algebraic equations, so called differential-algebraic equations (DAE) or descriptor models....

Observers for non-linear differential-algebraic systems (2009)

Erik Frisk

In this paper we consider design of observers for non-linear models containing both dynamic and algebraic equations, so called differential-algebraic equations (DAE) or descriptor models. The...

SENSOR SELECTION FOR OBSERVER FEEDBACK IN TURBOCHARGED SPARK IGNITED ENGINES (2009)

Per Andersson, Erik Frisk, Lars Eriksson

Abstract: Precise air/fuel control is necessary for low emissions in turbocharged (TC) SI-engines. Observers are often proposed for accurate cylinder air charge estimation in air/fuel controllers....

Dynamic Test Selection for Reconfigurable Diagnosis (2009)

Mattias Krys, Fredrik Heintz, Jacob Roll, Erik Frisk

Abstract — Detecting and isolating multiple faults is a computationally intense task which typically consists of computing a set of tests, and then computing the diagnoses based on the test...

Sensor Placement for Fault Isolation in Linear Differential-Algebraic Systems (2009)

Mattias Krys, Erik Frisk

Abstract: An algorithm is proposed for computing which sensor additions that make a diagnosis requirement specification regarding fault detectability and isolability attainable for a given linear...

FlexDx: A Reconfigurable Diagnosis Framework (2009)

Fredrik Heintz, Mattias Krys, Jacob Roll, Erik Frisk

Detecting and isolating multiple faults is a computationally intense task which typically consists of computing a set of tests, and then computing the diagnoses based on the test results. This paper...

DETERMINING A COMPONENT’S FAULT STATUS AND THE STATUS ’ READINESS (2009)

Jonas Biteus, Mattias Nyberg, Erik Frisk

Abstract: A diagnosis points at a set of components whose abnormal behavior could explain why a system does not function as intended, and a set of diagnoses points at different such sets of...

DETECTING KNOCK IN SPARK IGNITED ENGINES (2009)

Ylva Nilsson, Erik Frisk

Abstract: In this paper we consider signal processing algorithms for detecting knock, i.e. auto-ignition of unburned fuel, in spark-ignited engines. To operate an engine with optimal efficiency,...

A SYSTEMATIC INCLUSION OF DIAGNOSIS PERFORMANCE IN FAULT TREE ANALYSIS (2009)

Jonas Biteus, Erik Frisk, Mattias Krys, Lars Nielsen

Abstract: Safety is of major concern in many applications such as in automotive systems and aerospace. In these applications it is standard to use fault trees, and a natural question in many modern...

automotive (2009)

Esteban R. Gelso, Erik Frisk, Joaquim Armengol

Robust fault detection using consistency

IMPROVING DIAGNOSIS PERFORMANCES ON A TRUCK ENGINE MAKING USE OF STATISTICAL CHARTS (2009)

Antoine Berton, Erik Frisk, Mattias Nyberg

Abstract: A method to improve model based diagnosis for the air path of a truck engine is presented. Originally, inaccuracies in both the volumetric efficiency static model and sensors limited the...

EFFICIENT ELIMINATION ORDERS FOR THE ELIMINATION PROBLEM IN DIAGNOSIS (2009)

Erik Frisk

Abstract. A consistency relation is a constraint on the time evolution of known variables (and their time derivatives) that is fulfilled if the known variables are consistent with a model. Such...

Observer design and model augmentation for bias compensation with a truck engine application (2009)

Höckerdal, Erik, Frisk, Erik, Eriksson , Lars

A systematic design method for reducing bias in observers is developed. The method utilizes an observable default model of the system together with measurement data from the real system and estimates...

DIAGNOSIS OF EVAPORATIVE LEAKS AND SENSOR FAULTS IN A VEHICLE FUEL SYSTEM (2007)

Ingemar Andersson, Erik Frisk

Abstract: This paper describes a vacuum-decay based evaporative leak detection procedure for vehicle fuel systems. A physical model for an evaporative system is proposed containing parts for fuel...

Residual Generation in Stochastic Systems- A Polynomial Approach (2007)

Erik Frisk

This report describes a polynomial design algorithm for linear residual generation for stochastic systems in both continuous and discrete time. It is shown how the two main steps in the design...

Residual Generation For Fault Diagnosis Of (2007)

Systems Described By, Erik Frisk, Mattias Nyberg

An algorithm for designing linear residual generators is presented. A main result is that the algorithm is able to design residual generators for any model described by general linear...

A toolbox for design of diagnosis systems (2006)

Erik Frisk, Mattias Krys, Mattias Nyberg

Abstract: Design of diagnosis systems is a complex task that involves many different steps. Full understanding of all different parts of the design procedure requires deep knowledge on theory from a...

Business intelligence within the Swedish broadcasting industry (2005)

Gustafsson, Mariah, Frisk, Erik, Palmkvist, Pontus

The business environment has become more risky over the past decades. How do the companies prepare for the competitive environment and how are they working with risk identification and risk...

Business intelligence within the Swedish broadcasting industry (2005)

Gustafsson, Mariah, Frisk, Erik, Palmkvist, Pontus

The business environment has become more risky over the past decades. How do the companies prepare for the competitive environment and how are they working with risk identification and risk...

Residual Generation for Fault Diagnosis of Systems Described by Linear Differential-Algebraic Equations (2005)

Erik Frisk, Mattias Nyberg

Linear residual generation for DAE systems has been considered. In all results derived, no distinction between input and output signals is done. A complete characterization and parameterization of...

Lowering orders of derivatives in non-linear residual generation using realization theory (2005)

Erik Frisk

Abstract: Consistency relations are often used to design residual generators based on nonlinear process models. A main difficulty is that they generally include time differentiated versions of known...

Residual generation for fault diagnosis of systems described by general linear differential-algebraic equations (revised (2005)

Erik Frisk, Mattias Nyberg

Abstract: An algorithm for designing linear residual generators is presented. A main result is that the algorithm is able to design residual generators for any model described by general linear...

Improving Fault Isolability Properties by Structural Analysis of Faulty Behavior Models: Application to the DAMADICS Benchmark Problem (2003)

Erik Frisk, Dilek Düstegör, Mattias Krysander, Vincent Cocquempot

Structural analysis is a powerful tool for early determination of detectability /isolability possibilities. It is shown how di#erent levels of knowledge about faults can be incorporated in a...

Improving fault isolability properties by structural analysis of faulty behavior models: application to the DAMADICS benchmark problem (2003)

Erik Frisk, Mattias Krys, Vincent Cocquempot

Abstract: Structural analysis is a powerful tool for early determination of detectability/isolability possibilities. It is shown how different levels of knowledge about faults can be incorporated in...

Linkoping Studies in Science and Technology. Dissertations (2001)

No Residual Generation, Erik Frisk

The objective when supervising technical processes is to alarm an operator when a fault is detected and also identify one, or possibly a set of components, that may have been the cause of the alarm....

A minimal polynomial basis solution to residual generation for fault diagnosis in linear systems (2001)

Mattias Nyberg, Erik Frisk

Abstract: A fundamental part of a fault diagnosis system is the residual generator. Here a new method, the minimal polynomial basis approach, for design of residual generators for linear systems, is...

Residual Generation for Fault Diagnosis (2001)

Erik Frisk

The objective when supervising technical processes is to alarm an operator when a fault is detected and also identify one, or possibly a set of components, that may have been the cause of the alarm....

Residual generator design for non-linear, polynomial systems - a gröbner basis approach (2000)

Erik Frisk

Abstract: Design and analysis of residual generators for polynomial systems is considered. This paper presents a systematic procedure, given an input-output description of system dynamics, to design...

Order Of Residual Generators - Bounds And Algorithms (2000)

Erik Frisk

: This contribution analyses residual generators that perfectly decouples disturbances in linear systems. The analysis focuses on the orders of the residual generators and it is shown how low order,...

Order of Residual Generators - Bounds and Algorithms (2000)

Erik Frisk

This contribution analyses residual generators that perfectly decouples disturbances in linear systems. The analysis focuses on the orders of the residual generators. Easily computed bounds on...

Order of residual generators– bounds and algorithms (2000)

Erik Frisk

Abstract: This contribution analyses residual generators that perfectly decouples disturbances in linear systems. The analysis focuses on the orders of the residual generators and it is shown how low...

Residual generator design for non-linear, polynomial systems - a gröbner basis approach (2000)

Erik Frisk

Abstract: Design and analysis of residual generators for polynomial systems is considered. This paper presents a systematic procedure, given an input-output description of system dynamics, to design...

A description of the minimal polynomial basis approach to linear residual generation (1999)

Mattias Nyberg, Erik Frisk

A fundamental part of a fault diagnosis system is the residual generator. Here a new method, the minimalpolynomial basis approach, for design of residual generators for linear systems, is presented....

Using Minimal Polynomial Bases for Model-Based Fault Diagnosis - A Demonstration Document for PolyX, Ltd (1999)

Erik Frisk, Mattias Nyberg

This document is a demonstration document, prepared for PolyX Ltd., demonstrating the use of the Polynomial Toolbox for Matlab when designing residual generators for fault diagnosis. A brief...

Robust Residual Generation For Diagnosis Including A Reference Model For Residual Behavior (1999)

Erik Frisk, Lars Nielsen

: The main goal when synthesizing robust residual generators, for diagnosis and supervision, is to attenuate influence from model uncertainty on the residual while keeping fault detection...

A description of the minimal polynomial basis approach to linear residual generation (1999)

Mattias Nyberg, Erik Frisk

A fundamental part of a fault diagnosis system is the residual generator. Here a new method, the minimal polynomial basis approach, for design of residual generators for linear systems, is presented....

A minimal polynomial basis solution to residual generation for linear systems (1999)

Erik Frisk, Mattias Nyberg

A fundamental part of a fault diagnosis system is the residual generator. Here anewmethod,theminimal polynomial basis approach, for design of residual generators for linear systems, is presented. The...

Robust Residual Generation for Diagnosis Including a Reference Model for Residual Behavior (1999)

Erik Frisk, Lars Nielsen

Abstract: The main goal when synthesizing robust residual generators, for diagnosis and supervision, is to attenuate influence from model uncertainty on the residual while keeping fault detection...

A Minimal Polynomial Basis Solution to Residual Generation for Fault Diagnosis in Linear Systems (1998)

Erik Frisk, Mattias Nyberg

A fundamental part of a fault diagnosis system is the residual generator. Here a new method, the minimal polynomial basis approach, for design of residual generators for linear systems, is presented....

A Minimal Polynomial Basis Solution To Residual Generation For Fault Diagnosis In Linear Systems (1998)

Mattias Nyberg, Erik Frisk

: A fundamental part of a fault diagnosis system is the residual generator. Here a new method, the minimal polynomial basis approach, for design of residual generators for linear systems, is...

Residual Generation for Fault Diagnosis: Nominal and Robust Design (1998)

Erik Frisk

Diagnosis is the task to deduce, from observed variables of a system, if any component is faulty and if so, locate the faulty component. In a technical application, diagnosis is performed by ltering...

FDI with adaptive residual generation applied to a DC-servo (1997)

Erik Frisk, Mattias Nyberg, Lars Nielsen

Abstract: When parity equations are designed ad hoc., the low frequency gain of the fault-to-residual transfer function can become low or even zero which is highly undesirable. As a solution, a...

FDI with Adaptive Residual Generation Applied to a DC-Servo (1997)

Erik Frisk, Mattias Nyberg, Lars Nielsen

: When parity equations are designed ad hoc., the low frequency gain of the fault-to-residual transfer function can become low or even zero which is highly undesirable. As a solution, a systematic...

FDI with adaptive residual generation applied to a DC-servo (1997)

Erik Frisk, Mattias Nyberg, Lars Nielsen

Abstract: When parity equations are designed ad hoc., the low frequency gain of the fault-to-residual transfer function can become low or even zero which is highly undesirable. As a solution, a...

Model-based fault diagnosis applied to an SI-Engine (1996)

Erik Frisk, Lars Nielsen

A diagnosis procedure is an algorithm to detect and locate (isolate) faulty components in a dynamic process. In 1994 the California Air Resource Board released a regulation, called OBD II, demanding...

Using Minimal Polynomial Bases For Fault Diagnosis

Erik Frisk, Mattias Nyberg

A fundamental part of a fault diagnosis system is the residual generator. Design of residual generators to achieve perfect decoupling in linear systems is considered. A new method, the minimal...