Show simple item record

dc.contributor.supervisorSutton, Prof. Robert
dc.contributor.authorAnnamalai, Andy SK
dc.contributor.otherFaculty of Science and Environmenten_US
dc.date.accessioned2014-09-09T09:00:33Z
dc.date.available2014-09-09T09:00:33Z
dc.date.issued2014
dc.identifier299137en_US
dc.identifier.urihttp://hdl.handle.net/10026.1/3100
dc.description.abstract

An adaptive autopilot design for an uninhabited surface vehicle Andy SK Annamalai The work described herein concerns the development of an innovative approach to the design of autopilot for uninhabited surface vehicles. In order to fulfil the requirements of autonomous missions, uninhabited surface vehicles must be able to operate with a minimum of external intervention. Existing strategies are limited by their dependence on a fixed model of the vessel. Thus, any change in plant dynamics has a non-trivial, deleterious effect on performance. This thesis presents an approach based on an adaptive model predictive control that is capable of retaining full functionality even in the face of sudden changes in dynamics. In the first part of this work recent developments in the field of uninhabited surface vehicles and trends in marine control are discussed. Historical developments and different strategies for model predictive control as applicable to surface vehicles are also explored. This thesis also presents innovative work done to improve the hardware on existing Springer uninhabited surface vehicle to serve as an effective test and research platform. Advanced controllers such as a model predictive controller are reliant on the accuracy of the model to accomplish the missions successfully. Hence, different techniques to obtain the model of Springer are investigated. Data obtained from experiments at Roadford Reservoir, United Kingdom are utilised to derive a generalised model of Springer by employing an innovative hybrid modelling technique that incorporates the different forward speeds and variable payload on-board the vehicle. Waypoint line of sight guidance provides the reference trajectory essential to complete missions successfully. The performances of traditional autopilots such as proportional integral and derivative controllers when applied to Springer are analysed. Autopilots based on modern controllers such as linear quadratic Gaussian and its innovative variants are integrated with the navigation and guidance systems on-board Springer. The modified linear quadratic Gaussian is obtained by combining various state estimators based on the Interval Kalman filter and the weighted Interval Kalman filter. Change in system dynamics is a challenge faced by uninhabited surface vehicles that result in erroneous autopilot behaviour. To overcome this challenge different adaptive algorithms are analysed and an innovative, adaptive autopilot based on model predictive control is designed. The acronym ‘aMPC’ is coined to refer to adaptive model predictive control that is obtained by combining the advances made to weighted least squares during this research and is used in conjunction with model predictive control. Successful experimentation is undertaken to validate the performance and autonomous mission capabilities of the adaptive autopilot despite change in system dynamics.

en_US
dc.description.sponsorshipEPSRC (Engineering and Physical Sciences Research Council)en_US
dc.language.isoenen_US
dc.publisherPlymouth Universityen_US
dc.subjectAdaptive autopilot designen_US
dc.subjectUninhabited surface vehicleen_US
dc.subjectUnmanned surface vehicleen_US
dc.subjectModel predictive controlen_US
dc.subjectWeighted least squareen_US
dc.subjectKalman filteringen_US
dc.subjectLine of sight guidance systemen_US
dc.titleAn adaptive autopilot design for an uninhabited surface vehicleen_US
dc.typeDoctorateen_US
plymouth.versionFull versionen_US


Files in this item

Thumbnail
Thumbnail

This item appears in the following Collection(s)

Show simple item record


All items in PEARL are protected by copyright law.
Author manuscripts deposited to comply with open access mandates are made available in accordance with publisher policies. Please cite only the published version using the details provided on the item record or document. In the absence of an open licence (e.g. Creative Commons), permissions for further reuse of content should be sought from the publisher or author.
Theme by 
@mire NV