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Frex SimConMotion
I've been reading about the Frex motion system. It looks impressive in
the video! Lots of movement. Has anyone discussed the inaccurate motion cues that Frex system provides? The Frex system is generating motion cues opposite from what occurs in real life! For instance, the inner-ear sensations that the driver experiences will all be reversed from real life. Also, the pressure and tension changes the driver feels between his body and the seat while the seat is in motion are reversed from reality. The Frex approach seems to be to move the head of the driver around in the way it would in a real car. From that perspective the system seems OK, except that eye position movement of the driver is already modelled in current simulations. I guess you could just turn off the simulated head movement in the simulation while using the Frex system. Still, I'd hate to train and practice in that device, then jump in a real car expecting to go fast! Pat Dotson |
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Frex SimConMotion
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Frex SimConMotion
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Frex SimConMotion
I haven't tried it - only saw the video. Have you tried it? I'd be
interested to hear what you think about it. As I've outlined, I believe the movements of the Frex SimConMotion create inaccurate, conflicting motion cues. Please tell me where I'm wrong. Pat Dotson Trev B wrote: > Have you tried it? It tries to give you seat-of-the-pants feel. As > that's the aim, the movement is correct. > |
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Frex SimConMotion
I can tell you where you are wrong, 1st off your simulating the forces
applied the the body of a person, who is in the cockpit of a car/plane/train (stationary object inside a moving object) which is all done in combination with inherent visual cues from the games (notice the screen moves with you)... But, ride in the back of my pickup, when I gass the throttle, and you are standing up, you will fall backwards. It isnt really because you did anything but shifted the direction of center of gravity... in a chair however if mounted sturdy, you would just feel increased "G" forces which is being basically weight distributing across your bones and muscles. Much in the way tipping a chair backwards makes your body "shift it's weight" from the bottom of your butt to the back and {arms? as you catch yourself in some cases}... So the tilting platform to the right, to simulate the body being in a tight left turn, well It seems to simulate gforce loading of bones and muscles. Now, I agree, that the Frex cannot really simulate accurately, the forces of you hitting the wall at anything above running barfoot 12 year old could do top speed, I would guess for no other reason than legal liability as death could happen (and power demands LOL)... If you have not tried the "state fair" simulation movie theater trialers, your missing out, and I do know that when the picture dies, the motiions of the chairs and stuff are downright goofy and you are left with WTF feelings, but at the same time, if you dont have your tongue just right you will almost bite the damn thing off... wrote: > I haven't tried it - only saw the video. Have you tried it? I'd be > interested to hear what you think about it. > > As I've outlined, I believe the movements of the Frex SimConMotion > create inaccurate, conflicting motion cues. Please tell me where I'm > wrong. > > Pat Dotson > > > > Trev B wrote: >> Have you tried it? It tries to give you seat-of-the-pants feel. As >> that's the aim, the movement is correct. |
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Frex SimConMotion
Make your statement he
http://forum.rscnet.org/forumdisplay...prune=30&f=809 wrote: > I haven't tried it - only saw the video. Have you tried it? I'd be > interested to hear what you think about it. > > As I've outlined, I believe the movements of the Frex SimConMotion > create inaccurate, conflicting motion cues. Please tell me where I'm > wrong. > > Pat Dotson > > > > Trev B wrote: > >>Have you tried it? It tries to give you seat-of-the-pants feel. As >>that's the aim, the movement is correct. >> > > |
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Frex SimConMotion
> But, ride in the back of my pickup, when I gass the throttle, and you are > standing up, you will fall backwards. It isnt really because you did > anything but shifted the direction of center of gravity... That's Newton's first law. The truck accelerated, but there was nothing applying the acceleration to the body of the person who is standing up. So the person's body stays at rest and the person falls down as their feet get pulled out from under them. > in a chair > however if mounted sturdy, you would just feel increased "G" forces which is > being basically weight distributing across your bones and muscles. That's Newton's second law. Now the chair is applying the acceleration to the body of the person, and the person is pressed backward against the chair. This is where the Frex system gets it wrong. Here's why: Say you have a simulation of a person sitting in a sturdily mounted chair in the back of a pickup truck. The simulation is controlling a Frex SimConMotion system. The simulated truck is at rest and you are sitting in the Frex seat. Now the truck goes full throttle. What does the Frex seat do? It moves quickly backward. If you aren't belted in the seat, the seat will slide right out from under you. The only thing stopping you from sliding forward out of the chair is the harness. Is this what happens in real life? Of course not! If you were harnessed in the seat of a real pickup truck you will never feel forward pressure against the harness while the truck is accelerating forward. This opposite reaction created in the Frex seat is called a "conflicting motion cue". It's a cue that conflicts with reality, and with other cues that may be realistic. > Much in > the way tipping a chair backwards makes your body "shift it's weight" from > the bottom of your butt to the back and {arms? as you catch yourself in some > cases}... So the tilting platform to the right, to simulate the body being > in a tight left turn, well It seems to simulate gforce loading of bones and > muscles. Yes. This part of the Frex system is OK. Using gravity to simulate lateral force by tipping the chair. I'm not saying there is anything wrong with this part. If you tip the chair and leave it there, it can simulate a weak but realistic lateral force. But... I specifically said "while the chair is in motion". The problem is not what the chair feel like while it's stopped. The problem is what it feels like while it's in motion. If you've seen the video you have to agree that the seat is in near constant motion. For the reasons I've stated, ANYTIME the seat is in motion it is giving a conflicting motion cue. There is no denying this. It doesn't take any more than an 8th grade level of physics education to understand. There is a thread in the cockpit building section of RSC where a guy from Force Dynamics discusses this issue (not specifically in regards to Frex, but regarding the general design of a motion platform). I'm not saying the Frex system is worthless. It looks like a lot of fun and I'd love to have one. But at the same time there are inherent problems with its design if you are looking for high fidelity motion cueing. Pat Dotson |
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