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INDUSTRY

SirnfeeT 2009 isheld under the auspicesof the Simulation Industry Association ofAustra'ia (511'.1') Ltd ABN 13 087862619

te·CUBIC

EditorDr Elyssebeth LeighUniversity of Technology, Sydney

Published by the Simulation Industry AssociatIon of AustraliaABN 13 087 862 619

ISBN 0 9775257 6 7

©2009 Simulation Industry Association of Australia. Permission is herebygranted to quote any of the material herein, or to make copies thereof, fornon-commercial purposes, as long as proper attribution is made and thiscopyright notice is included. All other uses are prohibited without writtenpermission from the Simulation Industry Association of Australia.

For further information, contact:

Simulation Industry Association of AustraliaPO Box 226Lindfield , NSW, 2070Austra lia

www.siaa.asn.au

Email: exec@s iaa.asn.au

ii

SimTecT 2009 Paper Review Committee

Dr Elyssebeth Leigh (PapersCoordinator)

Ms Emily Andrew

Dr Jonathan Binns

Mr Anthony Cramp

Mr Alfred Devlvi

MrGary Eves

Mr Per Gustavsson

Mr Peter Hill

Mr Nick Howden

Dr Heath James

Mr John Marychurch

Dr Michael McGarity (Paper ReviewCoordinator)

Prof N K Mehta

Mr Roger Mulligan

Mr Daniel Munro

Prof Saeid Nahavandi

Dr John Olsen

Dr Simon Parker

Mr Craig Pepper

Mr Shane Rogers

Dr Peter Ryan

Dr David Stratton

Mr Philip Swadllng

Dr Andreas Tolk

Mr Grant Tudor

Mr Charles Tumltsa

Dr Susannah Whitney

Senior Lecturer, University of Technology,Sydney

Director, NCS Modeling & Simulation, RaytheonCompany

Researcher , MT&E, Australian Maritime College

Defence Scientist, Defence Science andTechnology Organisation

Senior Software Engineer, Northrop Grumman

Practice Lead, QinetiQ Consulting

Vice Manager, Ericsson Microwave Systems AB

Director, Simeon Services

Business Development Manager, CAEProfessional Services

Modelling and Simulation Discipline Lead,Defence Science and Technology Organisation

Solutions Architect, Thales Australia

Manager, Decision Support Services, CAEAustralia

Indian Institute of Technology Roorkee

Consultant

Associate, Booz & Company

Chair in Engineering, Deakin University

Lecturer , School of Mechanical andManufacturing Engineering, University of NewSouth Wales

Principal Research Scientist, Defence Scienceand Technology Organisation

Technical Lead, Boeing Defence Australia

Senior Manager, Systems Analysis Laboratory,Boeing Defence Australia

Principal Research Scientist , Defence Scienceand Technology Organisation

Leader, Distributed Simulation Laboratory,University of Ballarat

Chief Engineer - Simulation, Thales Australia

Senior Research Scientist, Old DominionUniversity, USA

Director, Army Simulation Wing

Virginia Modeling Analyses & Simulation Center,Old Dominion University, USA

Cognitive Scientist, Defence Science andTechnology Organisation

iii

iri1TecT 2009

Multiple Applications of Sailing SimulationMr John MOONEY;Yirtual Sailing Ply Ltd

johnmooney@virtual.net.au

Prof. Norman R. SAUI'I'DERSUniversity of Melbourne & Yirtua l Sailing Pty Ltd

n.saundersteunimelb.edu.au

Dr. Mark HABGOOD

University ofMelbourne & Yirtual Sailing Pty Ltd

mhabgoodseunimelb.edu.au

Dr. Jonathan R. BINNSAustralian Maritime Colleg e, University a/Tasmania

& Vinual Sailing Ply Ltd

j. binns@amc.edu.au

Training

Abstract. The world' s only ride-o n sailing simulator has been produced by the Austral ian company Virtua l Sailing(VS) for 10 years. Over this period significant research and development has occurred. On-going R&D isincorporated into new and retro-fitted to old simulators. During this time a number of users have owned and operatedthe VS·Laser, VSail-Trainer, VSail-Aeeess and VSail-Researeher simulators showing the way for a variety of uses.

The initial intention of the VSail-Trainer was for fitness training and physiological evaluation of elite athletes. Thishas shown promise with four sailors at the recent Olympics using and praising the simulator as a useful tool forfitness training and tactics and strategy development. The VSail-Researeher has been integrated into theundergraduate engineering course at the AMC to demonstrate the basic principles of sailing and simulation. As arehabilitation tool the VSail -Acce ss simulator has been used to introduce disabled people to sailing and reintroducesailors post accident (in Melbourne, Sydney , Miami and Auckland). A recent virtual regatta was organised by VSwith participants from Australia and the USA.

The area showing the greates t numbers of participants is in teaming to sail. Programs have been started withinAustralia for pre-teenagers through to university age students to learn to sail for the first time, adding simulation tothe more traditional learning methodologies. The use of simulation in this area shows great prom ise for increasingpatticipation and retention rates for the sailing industry as a who le.

Figure 1 The VSail-Researc her sailing simulationclassroom

1. INTRODUCTION

Sailing simulation has been used for the analysis oftacking (Masuyama, Fukasawa, & Sasagawa, (995),handicap assessmen t (Keuning, Vermeulen, &deRidder, 2005); design optimisation of engineering

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and human systems (Philpott & Mason, 2002; Scarponi,Shcnoi , Tumock, & Conti, 2006); and prediction ofstarti ng manoeuvres (Binns, Hoehkireh, DeBord, &Burns, 2008). Simulation as a laboratory tool has beenused in sailing for at least twenty years (Bursztyn,Coleman, Hale, & Harrison, 1988; Walls & Saunders,1995) continuing to the present day (Cunningham &Hale, 2007) and more recently generalised sail trainingis making usc of simulation (Binns, Bethwaite, &Saun ders, 2002). Each of these applications requiresvarying degrees of accuracy in the predictedparameters. This paper describes the application of thesimulation detailed in Binns, et a!. (2002) to the areas oftraining , engineering education and novice learningexerci ses.

2. THE UNDERLYING SIMULATION

The physical simulation has been achieved through anexplicit Euler time stepping procedure. From anumerical stability point of view this is a fairly clumsymethod, as time steps of greater than 0.1 s result inserious instabilities. However, it does provide aco nsistent method across a wide variety of co mputing

Figure 2 Simplified free body diagram of a dingbysailing to windward, showing the main components ofthe heel moment balance.

Figure 3 The hiking posture. Laser dinghies are wellknown for producing back injuries in competitivesailors. Top image is pre-remedial posture; bottom ispost-remedial following physiotherapy advice. Theability to take photos such as these for later analysis isunique to the sailing simulator (reproduced withpermission of the Olympic sailor, Krystal Weir).

3. OLYMPIC SAIL TRAINING

Through experience with the Victorian state youthsquad, it has become apparent that a sailing simulatorwill be a valuable tool for studying and correctinghiking posture. A sailing dinghy creates forces to

counteract hydrodynamic drag with a complicated forceand moment balance. The essential parts of the heelmoment balance are shown in thc free body diagram ofFigure 2. There is a large aerodynamic side force fromthe sail, which is balanced by a hydrodynamic sideforce from the centreboard and rudder. Since somedistance offsets the aerodynamic and hydrodynamicforces, a moment is created. This moment is balancedby the centre ofgravity of the sailor' s mass being offsetfrom the buoyancy force. The success of a competitivedinghy sailor is greatly influenced by the consistencyand size of thc balancing heel moment that thcy are ableto produce; that is the further they are able to sit (hike)from the centreline of the boat and the longer they canhold this position. This means that a sailor' s success ishighly influenced by their ability to hold a strenuousposition for long periods of time. As a consequence ofthe stresses involved, back pain appears to be quiteco mmon in competitive dinghy sailors. especially inLasers.

Training SimTecT 2009

power and advances in com puting power areimmediately realised without the need for re­programming. This method also explicitly ties thesimulation to real time.

To maintain a small time step the sailing simulation hasbeen simplified. Details of the simplifiedcharacteristics of the three dinghy classes used in thesimulation can be found in (Binns et al., 2(02). Sailinga real dinghy safely and efficiently is related more tofeci than it is to thinking about the complex system offorces and moments required to move the dinghyforward. Therefore the limiting factor in simplifyingthe physics of a sailing dinghy is that the feel of thesimulation must remain sufficiently close to a realdinghy, otherwise the illusion of sailing is lost to theuser, and the simulator is little more than a hikingbench. A quasi-dynamic measure of this feel can bemade both on-water and on the simulator. Essentially,this method of analysis involves setting a wind anglerelative to the dinghy' s heading and sailing the dinghyas fast as possible at that heading. Reasons for somediscrepancies between the model and full scale arediscussed in Binns, et al. (2002); however, it should benoted that these discrepancies do not upset thc feel ofthe simulator. A dynamic measure of the feel of asailing dinghy has been made by considering the time to

complete a tack. In the simplified simulation model theadded mass and damping of the hull was essentiallylumped into a fcw parameters. Realistic limits wereplaced on these lumped terms and users were allowed tovary the parameters within these realistic limits. Basedon the variations suggested, these parameters were non­dimensionalised and hence applied to all dinghiespermitted by the software.

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It should be considered unacceptable for young peopleto injure themselves through sailing with inadequatehiking posture. The top female Australian Junior LaserRadial sailor was out of sailing for several months at thebeginning of 2003, because of stress fractures in hervertebrae . Figure 3 shows this sailor 's hiking posturebefo re her bac k injury (top) and after re-edueation byher coach and physi otherapist (bottom). The ability totake pictures for analysis such as thes e is unique to thesailing simul ator . To take these during on-watertraining sessions would be extremely expensive andtime consuming. Such data collection would beimposs ible if reproducible conditions were required. Itis now planned to carry out a study of hiking posture inthe Victorian Youth squad, using a Virtual Sailingsimulator.

The sailor mentioned in the previous paragraph hasgone on to compete in the ope n classes of the Olympi cs,representing Australia in the Yngling class at the 2008Olympics. Three add itional athletes competed at theseOlym pics who have used the simulator, one Spanishcompetitor has purchased a unit for her sail trainingschool .

4. ENGINEERING EDUCATION

4.1 Introduction

Sailing yach t design is taught at the AustralianMaritime College (AMC) as an elective in the fourthyear of the Bachelor of Engineering degree . The des ignof a sailing yach t is necessarily dom inated by a numberof engineering approximations due to the complexity ofthe force balance at the air/water interface (Claughton,1998). Each of the approximations alluded to hasdefinit e physical meaning, which must be understoodby an engineer engaged to des ign a saili ng yacht. Anexample of such an approximation is the effec tiveaspeet ratio of the underwater appendages, which canbe equated to the efficiency of the plan form (Houghton& Brock , 1970).

The VSail -Researcher (see Figure I) was used todemonstrate and actively involve the students in theeffects of altering the underlying simulation parameters.In addition the process demonstrated to the students thedifficulties of performing and analysing experiments ona sailing yacht,

4.2 Participants

Seven final year BE students were divided into 3groups.

4.3 Proloeol

Each group was requested to analy se the availablesimulation parameters and estimate changes to theparam eters which would produce a simulation sailingquicker than the original set . Changes were only

491

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permitted on the boat side of the simulation, changes toenvironmental conditions werenot permitted.

Each group was then required to nominate one memberto be the sailor. The sailor wac; permitted to practice onthe simulator for 5 min utes. This allowed the sailor toget accustomed to the simulator witho ut overly tiringhim/h er.

The sailor then performed a race using the originalsimulation parameters. The length of the race typicallytakes two to three minutes.

Finall y a second race was performed by the sailor ofeach group durin g which the simulation parameterswere altered to those selected by the group .

4.4 Resu lts

The design parameter changes selected by the threegroups are listed in Table 1. To understand thesechanges a summary of the force and moment balance ofa sailing yacht follows.

A sailing yacht is able to progress through the waterdue to the lifting surface of the sail (aerodynamicforces ) balancing with the lifting surfa ces of theunderwater appendages , or rudder and centerboard(hydrodynamic forces ). As these surfaces are actin g aswings, the forces cao be easi ly increased by increasingthe surface area. However, the aerodynamic andhydrodynamic forces are separated by some distance,creating an overturning moment. Therefore to keep theyacht sailing in a straight line , a sig nificant rightingmoment is required. The speed of the yacht is thereforehighly dependent on the size of the sails, rudder andcenterboard and the available righting moment. Theparameters selected by the students in Table I show anattempt by each group to increase the aerodynamic andhydrodynamic forces.

Table 1 Design parameter shifts selected by the threegroups

G ro u p Parameter Change Summary

One • Sail area increased by 99%

• Centreboard area increased by127%

• Righting momen t increased by100%

Two • Centreboard effective aspeetratio increased bv 64%

Three • Sail area increased by 14%

• Sail effective aspect ratio

. increased by 6%

• Centreboard area increased by27%

• Centreboard aspeet ratioincreased bv 125%

The results of the test simulations were analysed byexamining the record ed res ults of the first 36 seconds ofsailing into the wind. During this time the performance

Train ing

of the simulation was assessed by calculating thedistance travelled into the wind and dividing by thetime taken (36 s) . This provides an immediat eassessment for a Velocity Made Good (VMG) into thedirection of the wind. The results of this analysis arepresented in Table 2, for which an increas e in VMGshows animprovementin sailing performance.

Table 2 Velocity Made Good (VMG) for each designgroup

Group VMG before VMG afterchange change

One 62.6 rn/min N/A

Two 56.8 mlmin 72.8 mlmin

Three 77.7 mlmin 88.4 mlmin

4.5 Discussion

Within Table 2 the first result of note was that GroupOne was unable to record a result after the suggesteddesignparameter modifications. This was because afterthe modifications were made the simulation was far toodifficult to sail. The instabilities introduced in the heelrotation were much too difficult even for an author ofthis paper, with some 6 years of sailing simulationexperience and over 20 years of competitive sailingexperience to overcome. It is believed that this hasoccurred because the stiffness of the system in heel (therighting moment) has been substanti ally increasedalong with the excitation forces (aero andhydrodynamic lifting surface forces), however thedamping has not been significantly increased.Therefore the damping ratio has been significantlydecreased. In addition to this there was no attempt byGroup One to increase the efficiency of the system,instead the total power available has been increasedindependent of efficiency, These two lessons wereeasily demonstrated in the sailing simulator classroom.

The results of Group Two and Three show a significantincrease in VMG when the design parametermodifications were made. An increase in VMG can bedirectly correlated to improved sailing performance.These two groups achieved the improvement inperformance by increasing the efficiency of the aeroand hydrodynamic lifting surfaces . Which gro upsucceeded the most is inconclusive based on theseresults. as a statistical measure would need to beestimated. Thi s is the final lessnn to be learnt by thestudents through simulation: even under the perfectlycontrolled environment of the sailing simu lator, thehuman influence can cloud design asses sment andrequire probabilistically based experimental procedures.

The lessons of dynamic stability; aero andhydrodynamic efficiency; and probabilisticrequirements of experiments involving humaninteraction are all lucidly and repeatable demonstrableusing simulation. If environmental factors were added ,then these engineering elements could not be isolated,

SimTecT 2009

in addition to an explosion in cost of this teachingexercise.

S. DISABLED SAIL TRAINING

Virtual Sailing invited three rehabilitation centres, whouse VSail-Aceess simulators in their rehabil itationprograms to participate in a "Virtual Regatta" as atribute to the Paralympics. The "Virtual Regatta"provided a means to bring the scattered VSail-Accesssimulators together.

A set of Sailing Instructions was drawn up and thechallenge issued to: Royal Talbot RehabilitationHospital (Melbourne, Australia); Royal RehabilitationHospital (Sydney, Australia); and SALM (Miami,Florida, USA).

Although it is possible to run the regatta live by linkingthe VSail simulators together on-line, it was decided toallow a two week window for eaeh institution to entertheir best times. The regatta was sailed around atrapezoid course in Liberty Motor Sailor boats with 14knots of wind . Each sailor was able to sail the coursethree times and register their best time. The best timeoverall won the trophy for their institution.

Royal Rehabilitation (Sydney) were the first to submittheir race times by their sailors Dale Williams a SydneySailability sailor and Phil Thompson a well knownSydney offshore sailor. The times were competitive butnot good enough to stave off Royal Talbot representedby Frank Kleintz, who had previously sailed a Hobie 16on the Gippsland Lakes before his accident 5 monthsago. Frank had a faster time and he took the lead. AtVirtual Sailing we nervously awaited the Americanentry from SALM. It did not go un· noticed that duringthe month of the regatta the 25th anniversary of thehistoric Austra lian victory in the America's Cupoccured. However. as with on water sailing, theweather played havoc with SALM and they batteneddown the hatches for a hurricane and were unable tosubmit a race result within the time limit. They havepromised to mount an America's Cup style challenge forthe next international challenge.

Figure 4 The VSail-Access simulator being used in theVirtual Regatta

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6. ABLE-BODIED NOVICE SAIL LEARNING

A VS2 Laser (the predecessor to the VSai l-Trainerpictured in Figure 5) simulator was used in a 2 day"Learn to sail" course for children at the Sandy BaySailing Club in Tasmania in December 2002. Twentyone of about 30 children (age range 8-14) hadinstruction on the simulator before going on the watcrin Optimist dinghies. The coaches reported that of thechildren who had been on the simulator, all of the girlsand boys over 10 years old were more confident andlearned on-water skill more rapidly than those who hadnot been on the simulator or boys 10 and under. Theproblems experie nced with these younger boys both on­water and on the simulator appeared to relate to a shortattention span.

In 2008, a school based instructional program wasorganized for 12 studen ts (Year 8) from Laverton HighSchool, Victoria using a VS-2 Laser simulator based atAltona Yacht Club, Victoria and a V-Sail Trainer at thenew Yachting Victoria sail training centre at theBoatshed on Albert Park Lake, Melbourne. Lessonswere organised by one of the authors ass isted by twomembers of Altona YC. The students partic ipated inhalf a dozen lessons in groups of 3-4, after which theirsimulator performance was assessed by Olympian SarahBlanck (Figure 5) and thcy had the opportunity to sailon Albert Park Lake in a variety of sailing dinghies.Unpredicted side effects were that the students' selfesteem and attitude to school work were reported bytheir teachers to have improved considerably and theprevious high incidence of truancy fell to zero.

A trial was completed in the University of Melbourne inwhich 30 novice sailors were assigned randomly to twoprograms: (1) A standard instruc tional programinvolving an initial theoret ical session followed by asimple introduction to on-water experience in Lasers ora Tasar under the supervision of coaches. (2) Asimulator course in which groups of 5-6 studentsattended 6 evening classes involving instruction on asimulator. After this the simulator students wereintroduced to sailing on the water (in Lasers and aTasar). A formal comparison of on-water performanceby both groups was not completed due to timeconstraints ; however some clear differences betweenthe groups were apparent. In the simulator group 4students were lost from one subgroup after the firstevening class , in favour of other student pursuits. Theother II completed the course and went sailing. Theypersisted with on-water sailing in spite of some difficultweather conditions, which involved several of thestudents capsizing. The coaches reported that all 11students could beat, tack and sit out (hike) withoutdifficulty. In contrast 8 of the on-water group gave upand thc rest had considerably more difficulty than thesimulator group in learning elementary boat handlingskills. From this preliminary study a drop-out rate of53% for the non-simulator group was strikinglydifferent to 27% for the simulator group. Also, it hasbeen reported that two of the simulator group were ableto sail unaccompanied; at the same point in lessonsnone of the non-simulator group were able to do this.

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Figure 5 The VSai l-Trainer being used to introduceschool children to sailing

7. CONCLUSIONS

The application of sailing simulation to solvingproblems has been growing through the work of anumber of different groups worldwide. This paper hasreported on four applications of a sailing simulator builtin Australia.

Firstly the simulation has found application for elitesailing athletes. This applicat ion has been forphysiological based research and remedialphysiotherapy advice as wcll as for training.

A second area of application is to engineeringeducation. For this application student educationalexperienees are greatly enhanced through simulation.Engin eering education dictates that students arerequ ired to understand the principles of aerodynamics,hydrodynamics and dynamic systems as they applytheir engineering skills to the design and construction ofsailing vessels . As a repeatable and realisablerepresentation of real world dynamics in the class room ,simulation is unsurpassed . As the VS simulator engineis based on ftrst principles engineering, students areable to gain immediate insight about design alterationssuch as foil shape changes and stabil ity increases.

The third application described within this paper is todisabled sail training. For this purpose simulat ionoffers a safe and comfortable introduc tion to sailing .The repeatable and recordable nature of simulation hasbeen used to invol ve disparate institutions in the samecompetition.

Finally , the application of simulation to beginner sailtrain ing has been explored through programs involvingpre-teenager children through to university agedstudents. For this last application evidence is emergin gthat simulation combined with actual on-water trainingcan increase retention rates of new participants forsailing, as well as having some unexpected positivepersonal consequences in socially disadvantagedchildren.

Training

REFERENCESBinns, J. R., Bethwaite, F. W., & Saunders, N. R. (2002).

Development of a more realistic sailing simulator,The 1st High Performance Yacht DesignConference (pp. 221-228 ). Auckland, NZ: RINA.

Binns, 1. R., Hochkirch, K., DeBord, F., & Bums , I. A.(2008). The devel opment and use of sailingsimulation for lACe starting manoeuvre training,The 3rd High Performance Yacht DesignConference. Auckland, NZ: RlNA .

Bursztyn, P. G., Coleman , S., Hale, T., & Harrison, J. (1988).Laboratory simulation of thephysiological demandsof singlehanded dinghy racing. Journal ofPhysiology. 400(14) .

Claughton, A. (1998). Balance of air and water forces . In A.Claugh ton, J. Wellicome & J. Sbenoi (Eds.), Sailing.Yacht Design - Theory (pp . 3-13). Edinburgh, UK:Addison Wesley Longman Limited.

Cunningham, P., & Hale, T. (2007). Physiological responsesof elite Laser sailors to 30 minutes of simulatedupwind sailing. Journal ofSports Sciences, 25(10),1109-1116.

Houghton, E. L., & Brock, A. E. (1970). Aerodynam ics fo rEngineering Students. London, UK: EdwardAmold.

Keuning, 1. A., Vermeulen, K. J., & deRidder, E. J. (2005). Ageneric mathematical model for the manoeuvringandtacking of a sailingyacht, The J7th ChesapeakeSoiling Yacht Symposium (pp . 143-163). Annapolis,USA: SNA."ffi.

Masuyama , Y ., Fukasawa, T., & Sasagawa, H. (1995).Tacking simulation of sailing yachts - numericalintegration of equations of motion and applicationof neural network technique, The 12th ChesapeakeSailing Yocht Symposium (pp. 117-131). Annapolis,USA:SNAME.

Philpott, A" & Mason, A. (2002). Advances in optimizationin yacht performance analysis, The 1st HighPerformance Yacht Design Conference (pp. 229­236). Auckland, NZ: RJNA.

Scarponi, M., Shenoi, R. A.• Tumock, S. R.. & Conti, P.(2006). Interactions between yacbt-crew systemsand racing scenarios combining behavioural modelswith VPPs, The 19th International HISWASymposium on Yacht Des ign and YachtConstruction (pp. 109-120) . Amsterdam, TheNetherlands: HISWA.

Walls, J. T., & Saunders, N. R. (1995). Comparison of staticand dynamic dinghy biking using a sailingergometer. Can trained and untrained sailors bedifferentiated? Proceedings of the AustralianPhysiological and Pharmacological Society,26(206P).

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