VIRTUAL REALITY PARACHUTE SIMULATION FOR TRAINING AND MISSION REHEARSAL

AIAA 2001-2061VIRTUAL REALITY PARACHUTE SIMULATIONFOR TRAINING AND MISSION REHEARSAL

Jeffrey R. Hogue*R. Wade Allen†Systems Technology, Inc.Hawthorne, CAJerry MacDonald‡Cliff Schmucker**SSK Industries, Inc.Lebanon, OHSteve Markham††Valentine Technologies, Ltd.Hampshire, UK

Arvid Harmsen‡‡Automatisering en AdviesbureauStuurboord, The Netherlands

ABSTRACTThis paper describes recent developments in a virtualreality (VR) training device developed to teach parachuteguidance and control from deployment through landing.Parachute training simulation originated over 12 yearsago for training to improve the safety and performance ofsmokejumper and military parachutists. Whileimprovements and developments continue for thesefunctions and are discussed in this paper, progress hasbeen made in applying this concept to a number of otherapplications such as sport jumping , arcade and themepark entertainment, museums, aircrew emergencies , andoperational mission planning and rehearsal includingGPS navigation.INTRODUCTIONThis parachute simulator1 currently allows the jumper todeploy a parachute during free fall, visually check thecanopy for proper deployment2, mitigate malfunctions,and cutaway and deploy a reserve parachute if required,then exert control and guidance through to landing. * Principal Specialist, Senior AIAA Member† Technical Director, AIAA Member‡ Project Engineer** President,†† Technical Director‡‡ Technical DirectorCopyright © 2001 by Systems Technology, Inc. Published by the American Institute of Aeronautics andAstronautics with Permission.A range of visual data base selections are available for agiven jump, and methods are now being developed toallow rapid preparation of visual and wind field databases for rehearsal of specific mission objectives. Thisprocess for developing mission rehearsal visual and windscenarios will incorporate available digital terrainprofiles, satellite or aerial photographic imagery ofground terrain and weather information. The simulatorhas also been interfaced with a commercial GPSnavigation device designed for parachuting, whichallows training in the use of this equipment for guidanceand navigation. This combined system is described inthis paper.

This parachute simulator has been modified andupgraded to provide various features to meetrequirements of a range of applications and theinterrelating benefits of these enhancements are thesubjects of this paper.

USDA FS FS-14/SF-10A Simulator DevelopmentsThe parachute simulator dynamics allow for properrepresentation of response to control inputs and windfields. Modeling the turning, pitching, rolling anddescent response of a given parachute required data onperformance and other information on significantnonlinear behavior that affects control sensitivity andoscillatory response. For example a new USDA ForestService (FS) parachute3, the FS-14 has improvedcharacteristics over the FS-12, including: faster forwardspeed, ability to fly backwards in brakes, slower decentrate, more rapid turn rate, and has been supplied in threedifferent sizes.

The higher performance of this parachute designrequired the development of a new version of the training2

Figure 2. Wind Visualization Through StreamerSimulation

flight simulator4 for Forest Service. This version wasadopted this year by all Forest Service training centers.It incorporates these improved flight dynamicscharacteristics and a number of enhanced trainingfeatures.

These include a simulator scene developed to model aspecific real-world Forest Service training landing zonewith the difficult landing challenges typical of theirrough terrain fire fighting operations, shown in Figure 1.Scene development for parachute simulation is a difficulttask because due to the flight vehicle’s steep glide slopeangles and the parachutists need to look directly down atthe landing zone below, towards the horizon fornavigation and collision avoidance, and completelyoverhead to assess canopy condition. As a consequence,scenes must include the large overall details required forflight simulations with the small size details encounteredin simulations for ground vehicles, with the furtherrequirement that objects look correct from overhead aswell as from horizontal viewpoint. This wide field ofview is precisely what mandated the use of VRtechnology.Figure 1. Simulated Montana USDA FS Landing ZoneInvisible 3D features like ambient winds can be adifficult concept to convey to a student. The streamervisualization feature, illustrated in Figure 2, shows a linerepresenting a 3-d view of the actual path taken by astreamer dropped from directly above the selected target.This allows the instructor to demonstrate the effects ofwind change with altitude and alert the student to anypotential problem areas. When this feature is in use, thestudent’s monitor shows the jump scene selected on thestartup options screen with a yellow curving line startingat the initial altitude selected over the jump spot. Thesimulator computes a simulated path that streamer wouldtake when dropped in the particular wind field selected.Previous post-simulated jump view options wereavailable to show the jump exactly as seen by the jumperor via a remote view of the jumper and jump scene froma view angle that can be moved by a joystick. While thisperspective was particularly useful in viewing the effectsof malfunctions and jumper motions, it and the previousjumper view playback mode presented problems in termsof understanding and critiquing of the navigational andcollision avoidance tactics adopted by the trainee. Forthis reason and at smokejumper request, a jump reviewwas added where the observer’s eyepoint tracks along thewindline above the jumper, and the joystick is not used.The jumper in the previous run is marked with a circle todistinguish it from any jump partner. This observation isuseful for understanding the parachutist’s path over theground and relative to other parachutists.