Copy No. _____ Defence Research and Recherche et développement Development Canada pour la défense Canada & DEFENCE DÉFENSE Simulation of Launch and Recovery of Small Craft Including Cable Collisions and Cable Tension from Deck Personnel A. Roy D. Steinke R. Nicoll Dynamic Systems Analysis Limited Prepared by: Dynamic Systems Analysis Limited 101-19 Dallas Road, Victoria, BC, Canada V8V 5A6 Project Manager: Dean Steinke, 902-407-3722 Contract Number: W7707-135587/001/HAL Contract Scientific Authority: Kevin McTaggart, 902-426-3100 ext 253 The scientific or technical validity of this Contract Report is entirely the responsibility of the contractor and the contents do not necessarily have the approval or endorsement of the Department of National Defence of Canada. Defence R&D Canada – Atlantic Contract Report DRDC Atlantic CR 2013-136 August 2013 This page intentionally left blank. Simulation of Launch and Recovery of Small Craft Including Cable Collisions and Cable Tension from Deck Personnel A. Roy D. Steinke R. Nicoll Prepared by: Dynamic Systems Analysis Limited 101-19 Dallas Road, Victoria, BC, Canada, V8V 5A6 Project Manager: Dean Steinke 902-407-3722 Contract Number: W7707-135587/001/HAL Contract Scientific Authority: Kevin McTaggart 902-426-3100 ext. 253 The scientific or technical validity of this Contract Report is entirely the responsibility of the Contractor and the contents do not necessarily have the approval or endorsement of the Department of National Defence of Canada. Defence Research and Development Canada – Atlantic Contract Report DRDC Atlantic CR 2013-136 August 2013 c Her Majesty the Queen in Right of Canada, as represented by the Minister of National Defence, 2013 c Sa Majest´ela Reine (en droit du Canada), telle que r´epr´esent´ee par le ministre de la D´efense nationale, 2013 Abstract This report describes the simulation of launch and recovery of a small boat from a ship using a boom crane. The simulation was developed using the existing Ship Mechanical Systems Application Programmer Interface (SMS API). The SMS API was extended to include modelling of collisions between cables and solid objects, which can include a ship or a small boat. The influence of tag lines being handled by deck personnel was modelled, with a winch model being used to approximate the cable tension being applied by a person on deck. Simulation components were verified by comparison with a number of test cases. A complete launch and recovery scenario was simulated and visualized. Resum´ e´ Le pr´esent rapport d´ecrit la simulation de mise `a l’eau et de r´ecup´eration d’une pe- tite embarcation `a partir d’un navire `al’aide d’une grue `afl`eche. La simulation a ´et´e d´evelopp´eea ` l’aide de la SMS API (Ship Mechanical Systems Application Programmer Interface) existante. La SMS API a ´et´e´etendue pour inclure la mod´elisation des col- lisions entre les cˆableset les objets solides, ce qui peut comprendre un navire ou une petite embarcation. L’influence des cˆables stabilisateurs manipul´es par le personnel du pont a ´et´emod´elis´ee, avec un mod`ele de treuil utilis´epour obtenir une approximation de la tension des cˆablesappliqu´eepar une personne sur le pont. Les ´el´ements de simu- lation ont ´et´ev´erifi´es en les comparanta ` un nombre de cas d’essai. Un sc´enario de mise `a l’eau et de r´ecup´eration complet a ´et´e simul´e et visualis´e. DRDC Atlantic CR 2013-136 i This page intentionally left blank. ii DRDC Atlantic CR 2013-136 Executive summary Simulation of Launch and Recovery of Small Craft Including Cable Collisions and Cable Tension from Deck Personnel A. Roy, D. Steinke, R. Nicoll; DRDC Atlantic CR 2013-136; Defence Research and Development Canada – Atlantic; August 2013. Introduction: Launch and recovery of small boats has become an increasingly im- portant part of naval operations. This report describes extension of the existing Ship Mechanical Systems Application Programmer Interface to improve simulation fidelity for launch and recovery of small boats. Principal Results: Modelling of collisions between flexible cables and solid objects was implemented in the Ship Mechanical Systems Application Programmer Interface. In addition, handling tag lines by deck personnel was simulated using a winch model. DRDC Atlantic ran the delivered launch and recovery simulation and found that it ran 600 times slower than real time. Much of the computational time was likely devoted to modelling of collisions between cables and solid objects. Visualizations of the launch and recovery simulation suggested that physical phenomena were being correctly modelled. Significance of Results: Simulation of launch and recovery simulation is promising for applications such as training and engineering design. Validation using full-scale trial data and increased computational speed are two recommended areas for development. Future Plans: Defence R&D Canada will continue to work on development of simu- lation of launch and recovery. DRDC Atlantic CR 2013-136 iii Sommaire Simulation of Launch and Recovery of Small Craft Including Cable Collisions and Cable Tension from Deck Personnel A. Roy, D. Steinke, R. Nicoll ; DRDC Atlantic CR 2013-136 ; Recherche et developpement´ pour la defense´ Canada – Atlantique ; aoutˆ 2013. Introduction : La mise `a l’eau et la r´ecup´eration de petites embarcations sont une partie de plus en plus importante des op´erations navales. Ce rapport d´ecritl’extension de la SMS API (Ship Mechanical Systems Application Programmer Interface) existante pour am´eliorer la fid´elit´e de la simulation pour la mise `a l’eau et la r´ecup´eration de petites embarcations. R´esultats principaux : La mod´elisation des collisions entre les cˆablesflexibles et les objets solides a ´et´e mise en œuvre dans la SMS API. De plus, la manipulation des cˆables stabilisateurs par le personnel de pont a ´et´e simul´ee `a l’aide d’un mod`ele de treuil. RDDC Atlantique a effectu´e la simulation de mise `a l’eau et de r´ecup´eration et a d´ecouvert qu’elle se faisait 600 fois plus lentement qu’en temps r´eel. Une bonne partie du temps de calcul ´etait probablement d´edi´ee `alamod´elisation des collisions entre les cˆableset les objets solides. La visualisation de la simulation de mise `al’eau et de r´ecup´eration sugg´eraitque les ph´enom`enesphysiques ´etaient mod´elis´es correctement. Importance des r´esultats : La simulation de la mise `a l’eau et de la r´ecup´eration est prometteuse pour les applications comme la formation et la conception technique. La validationa ` l’aide de donn´eesd’essai pleine ´echelle et la vitesse de calcul augment´ee sont deux domaines recommand´espour le d´eveloppement. Travaux ult´erieurs pr´evus: Recherche et d´eveloppement pour la d´efense Canada continuera `a travailler au d´eveloppement de la simulation de la mise `a l’eau et de la r´ecup´eration. iv DRDC Atlantic CR 2013-136 Table of contents Abstract........................................ i R´esum´e ........................................ i Executive summary .................................. iii Sommaire....................................... iv Tableofcontents................................... v Listoffigures..................................... vii Listoftables..................................... ix 1 Introduction.................................... 1 2 Overview of narrow phase collision detection methods ............. 3 2.1 Narrow phase collision detection algorithms ............... 3 2.2 Geometricconsiderations......................... 4 2.3 Considerations for collision detection between cables and rigid bodies . 4 2.4 TheBVHapproach............................ 5 2.5 TheSGOapproach............................ 7 3 Detailed description of selected narrow phase cable collision detection methods 10 3.1 Bounding volume hierarchy ........................ 10 3.1.1 Leaf node collision checks .................... 12 3.1.1.1 LinesegmentandpolyhedronMSDquery...... 12 3.1.1.2 LinesegmentandpolygonMSDquery........ 12 3.1.2 BVforconvexpolyhedra..................... 13 3.2 Stochastic global optimisation ...................... 14 3.2.1 Unconstrainedcombinatorialstage............... 14 3.2.1.1 Finding the closest polygon for random pairs .... 15 3.2.2 Exploitingtemporalcoherence.................. 15 3.2.3 Localsearch............................ 16 3.2.4 ComplexityofSGOmethod................... 16 4 Broad phase collision detection ......................... 17 5 Modifications to collision detection code infrastructure ............ 18 5.1 The CollisionHandler class ........................ 18 5.2 The CollObjCubicSpline class ...................... 19 6 Contactdynamicsmodel............................. 20 7 Humandeckhandusingthewinchmodel.................... 22 8 Launchandrecoverysimulationchallenges................... 23 8.1 Addressing master-slave SimObject relationships ............ 23 8.2 Complications due to coarse cable contact mesh ............ 24 8.3 MinorchangestotheL&Rsimulationscriptandsetup......... 25 9 ManualUpdates................................. 28 9.1 Adding CollisionObjectstoSimObjects................ 28 DRDC Atlantic CR 2013-136 v 9.1.1 Adding collision objects to Payloads .............. 28 9.1.2 Adding a collision object to a Cable .............. 29 9.2 The CollisionHandler class....................... 29 9.2.1 Creating a CollisionHandler object .............. 29 9.2.2 Adding SimObjectstotheCollisionHandler ......... 30 9.2.3 Telling the CollisionHandler to ignore SimObject pairs . 30 9.2.4 AdvancingTime......................... 30 10SimulationResults...............................