feedback not simulation

hi guys,
be great to have some idea if what i am after is attainable. im sorry but i know very little on this subject as yet.
what i am after trying to construct is a feedback mount for a seat. i am not trying to simulate a cars motion, or the correct sensation for the driver. what i am trying to achieve is a simple 2 axis movement mount that will allow me to feel braking force and also feel traction loss as you reach critial interia forces while cornering. the way i was anticipating this to work was to have a universal pivot the front of the seat mount and a slidder rail at the rear. then two simple motors (wiper or whatever) to produce the motion in the two axis.
normal cornering dosnt require any motion, but the seat begins to slide as front or rear virtual wheels begin to lose traction, and this is progressive untill the point where you would spin, obviously being farthest travel. the braking feedback of course being progressive and relative to speed/braking force.
so, can i achieve this with the read game data? does it sound a reasonable project to embark on?

thanks for any input

Re: feeback not simulation

I think the problem is that you still have to read axis information from the game and converting that to motion.
This requires about the same electronics and mechanical work as a full 2dof simulator. (at least electronics)
So you have to ask yourself why you only want to have the feedback and not simulated movement.
Because in the end you could have a simulator for the same amount of effort (I think)

Re: feeback not simulation

a good point.
well i think for me, a full motion simulation is only really a worthwhile objective if you go the full course and have wheel pedals and monitor moving on same platform. much as i admire what people have done, i dont think i would want the full motion if my view wasnt moving with me. so then the only real purpose is as an aid to driving in the game...just as a feedback wheel can be an aid, or a vibrating brake pedal. the concept i have is to be small, light and simple (mechanically), so it looks no different or takes no more space than a normal seat mount.
must confess, the electronics side is what i find daunting, but realise its the most important part of such a project

well I agree with you about the screen moving with the simulator.
And I think you're referring to the frex style simulator.
But with the joyrider based simulator you will get some g-force simulation. 2dof in this case pitch and roll.
And the screen is mounted on the frame.
http://en.wikipedia.org/wiki/Six_degrees_of_freedom
now witch type of dimension are you referring to.
Because I'm thinking that your only talking about back and forward.

you mean movement? im talking of pitch and yaw.
you see the trouble i see with many of these 2dof platforms is that all the really usefull feedback information is lost because you are trying to give effect of forces during cornering. what i am suggesting is that i dont need that, all i want is the usefull information being given to me through my butt. i dont need to feel any yaw during cornering at all, unless i am starting to slide and lose traction. thats what i want a feedback mount to transmit to me.
i guess what im saying is i want pitch movement for braking force, and yaw to provide rear traction loss effect (dosnt have to be just rear, but thats best way to describe it i think)

well I haven't seen anything like it but I am interested.
Well for the electronics part just build
viewtopic.php?f=25&t=559 amc 1.5 the movement controller
with
viewtopic.php?f=27&t=820 DSMHB 1.2 this drives the motors.
the only problem is that the yaw axis isn't made on this forum (as far as i know).
The other option is to build you own controller.
This requires some research but is doable.

thanks for the links, its all helpfull.
i'll do a better drawing to show the mechanical layout i had in mind....but as you say, thats the easy bit

hmmm,
seems them fellows at simxperiance doing what i want with yaw
http://www.x-simulator.de/forum/rear-traction-loss-simulation-vids-t2427.html?hilit=rear traction

wonders if their sx 3000 controler could be adapted for this. scn5s would be overkill for the ammount of movement id want

Hi there

I just joined and was looking through to see if someone was trying to make the same as me - and this looks like it.

I too want just feedback, rather than full motion -no, let me clarify, I'd LOVE full motion, but without a big budget and some clever engineering solutions, I don't think that I could achieve an acceptable setup at home. One of the reasons for this is that the full 6dof setups are great for the relatively slow and gentle movement of flight sims but fundamentally flawed for race sims. If you think about it, the actual motion you would experience is counter-intuitive.

Let me explain why I think that. Let's take just one force, braking. When you brake, essentially your head and body are pulled forwards; to simulate that, you would have to tilt the rig forwards, so gravity pulls you 'forwards'. The harder the braking, the more the tilt has to be. The problem comes when you consider that when you start tilting the rig forwards, you are actually rotating it. This means that the movement to tilt the rig will actually feel like acceleration, not braking, until the rig has stopped in its tilted forward position. Your head wants to stay where it is, but the tilting movement is trying to move it forwards, which you sense as acceleration. This will happen every time the rig wants to tilt to a new position, so you will be receiving momentary accelerations when you brake, and momentary braking force when you accelerate.

The only way to properly simulate the sharp, ever changing G forces of a car would be to attach strung cords to your arms and head that are pulled by actuators; or maybe a suit lined with magnets that is repelled or attracted by external electromagnets, although what health and safety implications that has I couldn't begin to guess at.

So for me feedback is what I'm looking for as well.

Les

Double post, sorry guys

Les

Well, you are partially right on this. The 6.DOF device you are talking about is called a Stewart platform, and it is not typically programed to do what you say. These simulators normally will swing on a relatively horizontal plane on the fore/aft and sideways movements, as well as yaw. Only at the end of the movements will the platform initiate any form of rotation about the drivers center of mass to offer sustainment. Typically this must be followed with a washout motion to allow the actuators additional freedom to move concurrently in response to other forces.

This ending maneuver where pitch and roll is required does indeed create confusion for the mind. But the initial swing motions are correct and can be very forceful and realistic. The ending of the motion can be troublesome and definitely dilutes the reality, possibly introducing enough sensory errors to cause distractions compared to driving reality. This is a limitation of the Stewart platform at least when it comes to vehicle, especially racing, simulation.

R-eng