Motion Platforms ??

Anyone with experience on a *real* racing simulator - with a motion platform and high-quality (anti-aliased, texture-mapped) graphics ?? Yeah this is a big ticket item, but compared to the bucks it can take to really go racing, it might be pretty cost effective - and I could go racing any time anywhere - no 6 hour tow to Road Atlanta twice a year. I know how to do the graphics, and I figure I can find out about the vehicle dynamics somewhere, but what about the motion ? My experience on track is that my eyes tell me what other cars are doing and my *** tells me what *my* car is doing. Anyone have info on a cost effective motion platform good enough to simulate something like a Formula Ford - one person, seat, controls, fiberglass***pit, helmet mounted display - say 350 lbs total payload simulating 1G max ??? Nick England

I don't know the acceleration and travel parameters, but at the IAAPA (International Association of Amu***t Parks and Attractions) exhibition in late November, there were large and small motion platforms running both canned and interactive experiences. A real blast. One small motion platform was running a simulation of driving through the rather dark hilly countryside around a Gothamesque city. The motion was decent and the database nice. A good ride even though you were constrained to stay on the road. Still you could really feel it when you rubbed the curbs that kept you roadbound. The platform was a large box (perhaps 6'D X 5'H x 3'W) on a three or four point support arrangement with two pistons diagonally supporting each point. McFaddin built the motion platform (I think in the $30-40K range). A small company named Xatrix did the visual database. Gemini did the application and dynamics. And an SGI Reality Engine provided the the anti-aliased, texture-mapped graphics McFaddin also showed a slightly larger platform running a Batman film-based ride. Also, Magic Edge makes an unconventional one person game pod that they were showing at IAAPA. Supported only at the tail, it can turn you upside down. Just the thing for when you roll the car! On the lower end (no motion) Namco's new Ridge Racer arcade game (similar 3D textured graphics to Air Combat, but with a better database) is HOT. Air Combat and Ridge Racer were maintaining better frame rates (60Hz!!??) than a lot of the stuff running on big iron, and go for only $15K a pop. rgds, -jim helman 415/390-1151

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>Anyone with experience on a *real* racing simulator - with a motion platform >and high-quality (anti-aliased, texture-mapped) graphics ?? >Yeah this is a big ticket item, but compared to the bucks it can take >to really go racing, it might be pretty cost effective - and I could >go racing any time anywhere - no 6 hour tow to Road Atlanta twice a >year. >I know how to do the graphics, and I figure I can find out about the >vehicle dynamics somewhere, but what about the motion ? My experience >on track is that my eyes tell me what other cars are doing and my *** >tells me what *my* car is doing. >Anyone have info on a cost effective motion platform good enough to >simulate something like a Formula Ford - one person, seat, controls, >fiberglass***pit, helmet mounted display - say 350 lbs total payload >simulating 1G max ??? >Nick England

I was reading an artical in one of the British Institution of Electrical Engineers journals a few months ago about an English firm who had developed a motion platform based on electrical rather than hydraulic motivators. I've just got the artical. Its in the September 1993 copy of the IEE Review p216. The product is called PEMRAM it uses a tubular 'linear motor' ( no longer linear but I hope it explanes what I mean). There is an example in the artical of a device capable of supporting 2 tonnes and producing a thrust of 1 tonne over 250 mm. The idea is that they are a lot cheeper than the hydraulic systems and that the system is soft (uses air springing) so there is non of the fluid shock that you get with hydraulic systems. Also its electrical so you dont need all that messy fluids and mechanical interfaces etc. The motion bandwidth is above 10Hz which sould be enough to provide the required user feedback for a simulator system. Let us hope that the avalibility of cheep systems like this will make realistic simulation an available technology.

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>>Anyone have info on a cost effective motion platform good enough to >>simulate something like a Formula Ford - one person, seat, controls, >>fiberglass***pit, helmet mounted display - say 350 lbs total payload >>simulating 1G max ??? >I was reading an artical in one of the British Institution of Electrical >Engineers journals a few months ago about an English firm who had developed a >motion platform based on electrical rather than hydraulic motivators. I've just >got the artical. Its in the September 1993 copy of the IEE Review p216. The

(stuff about linear actuator deleted) Thanks, I'll look it up. While in England last month I rode on two motion platforms, one in the Imperial War Museum, the other a Hughes/Rediffusion machine in the terminal at Gatwick airport. I assume they were hydraulic, but to tell the truth I didn't look closely. Neither were interactive - the Imperial War Museum simulated a Mosquito bomb run using actual WWII film, the other had a choice of auto racing (an awesome hillside track in Australia - where's that ?), F-16 dogfight, auto rally, downhill ski, bobsled, etc. Check it out. Back on the subject at hand - I have got some info from MOOG INC. on a motion platform they make using such linear electric actuators - designed for amu***t park attractions it seems - payload of 9000 lb, 4 degrees of freedom. This is way too big (for 20 people at a time at least) and way too expensive ($325,000) for my needs but here's what you get - 9000 lb payload 2.5 G's max (emergency stop) 5 msec update rate 13 ft x 15 ft flying platform excursion velocity acceleration pitch 22 deg 20deg/sec 150deg/sec**2 roll 25 deg same same vert 21 in. 20 in/sec 0.6G for 7000lb. (depends on load) (heave) long 32 in same 0.4G for 7000lb. (ditto) (surge) I'm gonna check and see what they make that is quite a bit smaller. Moog Inc East Aurora,NY 716/652-2000 Does anyone know if 4 DOF is sufficient for a race car simulator or is a full 6 DOF system necessary? Just thinking about it, it seems that roll might be an effective substitute for sideways translation (what is the term I need here? slip?). It seems yaw would be necessary to simulate things like intentionally inducing rotation with trailing throttle oversteer - or the beginnings of a spin. When I am on track it certainly seems that much of my sense of just how far to hang the tail out depends on a sense of yaw. Actually, I need to read some more about this somewhere - trying to be analytical about what I was experiencing during a race is kinda difficult - too much adrenaline poisoning I suspect !! Any suggestions of where to read about vehicle simulation in general and motion simulation in particular ??? Nick