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• #### A Framework for Diagnosis of Critical Faults in Unmanned Aerial Vehicles ﻿

(Conference object; Journal article; Peer reviewed, 2014)
Unmanned Aerial Vehicles (UAVs) need a large degree of tolerance towards faults. If not diagnosed and handled in time, many types of faults can have catastrophic consequences if they occur during flight. Prognosis of faults ...
• #### Adaptive Feedforward Control of Exhaust Recirculation in Large Diesel Engines ﻿

(Journal article; Peer reviewed, 2017)
Environmental concern has led the International Maritime Organization to restrict NO$_x$ emissions from marine diesel engines. Exhaust gas recirculation (EGR) systems have been introduced in order to comply to the new ...
• #### Adaptive Observer for Nonlinearly Parameterised Hammerstein System with Sensor Delay - Applied to Ship Emissions Reduction ﻿

(Journal article; Peer reviewed, 2017)
Taking offspring in a problem of ship emission reduction by exhaust gas recirculation control for large diesel engines, an underlying generic estimation challenge is formulated as a problem of joint state and parameter ...
• #### Adaptive Observer for Nonlinearly Parameterised Hammerstein System with Sensor Delay - Applied to Ship Emissions Reduction ﻿

(Journal article; Peer reviewed, 2017)
Taking offspring in a problem of ship emission reduction by exhaust gas recirculation control for large diesel engines, an underlying generic estimation challenge is formulated as a problem of joint state and parameter ...
• #### Backlash estimation for industrial flexible drive-train systems ﻿

(Journal article; Peer reviewed, 2017)
Backlash in gearing and other transmission components is a common positioning-degrading phenomenon that develops over time in industrial machines. High-performance machine tool controls use backlash compensation algorithms ...
• #### Calculation of Critical Fault Recovery Time for Nonlinear Systems Based on Region of Attraction Analysis ﻿

(Journal article; Peer reviewed, 2014)
In safety critical systems, the control system is composed of a core control system with a fault detection and isolation scheme together with a repair or a recovery strategy. The time that it takes to detect, isolate, and ...
• #### Centralised versus Decentralised Control Reconfiguration for Collaborating Underwater Robots ﻿

(Journal article, 2015)
The present paper introduces an approach to fault-tolerant reconfiguration for collaborating underwater robots. Fault-tolerant reconfiguration is obtained using the virtual actuator approach, Steffen (2005). The paper ...
• #### Combined Geometric and Neural Network Approach to Generic Fault Diagnosis in Satellite Actuators and Sensors ﻿

(Journal article; Peer reviewed, 2016)
This paper presents a novel scheme for diagnosis of faults aﬀecting the sensors measuring the satellite attitude, body angular velocity and ﬂywheel spin rates as well as defects related to the control torques provided by ...
• #### Compositional Finite-Time Stability Analysis of Nonlinear Systems ﻿

(Chapter; Peer reviewed, 2014)
This paper, investigates finite-time stability and finite-time boundedness for nonlinear systems with polynomial vector fields. Finite-time stability requires the states of the system to remain a given bounded set in a ...
• #### Condition monitoring of spar‐type floating wind turbine drivetrain using statistical fault diagnosis ﻿

(Journal article, 2018)
Operation and maintenance costs are significant for large‐scale wind turbines and particularly so for offshore. A well‐organized operation and maintenance strategy is vital to ensure the reliability, availability, and ...
• #### Constrained multi-body dynamics for modular underwater robots — Theory and experiments ﻿

(Journal article, 2018)
This paper investigates the problem of modelling a system of interconnected underwater robots with highly coupled dynamics. The objective is to develop a mathematical description of the system that captures its most ...
• #### Control surface fault diagnosis with specified detection probability — Real event experiences ﻿

(2013 International Conference on Unmanned Aircraft Systems (ICUAS);, Chapter; Conference object; Peer reviewed, 2013)
Diagnosis of actuator faults is crucial for aircraft since loss of actuation can have catastrophic consequences. For autonomous aircraft the steps necessary to achieve fault tolerance is limited when only basic and ...
• #### Control-Oriented Model of Molar Scavenge Oxygen Fraction for Exhaust Recirculation in Large Diesel Engines ﻿

(Journal article; Peer reviewed, 2016)
Exhaust gas recirculation (EGR) systems have been introduced to large marine engines in order to reduce NO$_x$ formation. Adequate modelling for control design is one of the bottlenecks to design EGR control that also meets ...
• #### Cooperative Rendezvous and Docking for Underwater Robots Using Model Predictive Control and Dual Decomposition ﻿

(Chapter, 2018)
This paper considers the problem of rendezvous and docking with visual constraints in the context of underwater robots with camera-based navigation. The objective is the convergence of the vehicles to a common point while ...
• #### Diagnosis of Airspeed Measurement Faults for Unmanned Aerial Vehicles ﻿

(Journal article; Peer reviewed, 2014)
Airspeed sensor faults are common causes for incidents with unmanned aerial vehicles with pitot tube clogging or icing being the most common causes. Timely diagnosis of such faults or other artifacts in signals from airspeed ...
• #### Diagnosis of CO Pollution in HTPEM Fuel Cell using Statistical Change Detection ﻿

(Journal article, 2015)
The fuel cell technologies are advancing and maturing for commercial markets. However proper diagnostic tools needs to be developed in order to insure reliability and durability of fuel cell systems. This paper presents a ...
• #### Diagnosis of Wing Icing Through Lift and Drag Coefficient Change Detection for Small Unmanned Aircraft ﻿

(Journal article, 2015)
This paper address the issue of structural change, caused by ice accretion, on UAVs by utilising a Neyman Pearson (NP) based statistical change detection approach, for the identi cation of structural changes of xed wing ...
• #### Diagnostic monitoring of drivetrain in a 5 MW spar-type floating wind turbine using Hilbert spectral analysis ﻿

(Journal article; Peer reviewed, 2017)
The objective of this paper is to investigate the frequency-based fault detection of a 5MW spar-type floating wind turbine (WT) gearbox using measurements of the global responses. It is extremely costly to seed managed ...
• #### Drillstring Washout Diagnosis using Friction Estimation and Statistical Change Detection ﻿

(Journal article; Peer reviewed, 2015)
In oil and gas drilling, corrosion or tensile stress can give small holes in the drillstring, which can cause leakage and prevent sufficient flow of drilling fluid. If such \emph{washout} remains undetected and develops, ...
• #### Early pack-off diagnosis in drilling using an adaptive observer and statistical change detection ﻿

(Journal article, 2015)
Pack-off is a partially or complete blocking of the circulation flow in oil and gas drilling, which can lead to costly delays. Early detection and localization of a pack-off is crucial in order to take necessary actions ...