2dof + Traction Build.

[yokoyoko]

Yokoyoko, what are the overall dimensions of your sim ?

I don't know all dimensions from memory - I will add this later here in the thread. But I know that the dimensions in length or width did not change during the upgrade from a 2dof seat mover to the current design. Just the height is increased abou 10cm!

The front bearing is under the pedals ( I use a similar bearing as shown above). The rear bearings are placed under the motors for the seat movement (longitudinal and lateral). ---> You see NO change in "important" dimension.

[bodgy]

Just aquiring materials at the moment. I will go with the central hub design because it is simple and if it doesn't work I can easily move the pivot point forward and support the rear with rolloer bearings (or more likely a skateboard truck I have laying around).

I know I am new to simulators and I have never experienced one but thinking about the spinning vs sliding thing I am not totally convinced the sliding action would be more realistic. In my mind most vehicles have the driver sitting at the central point of the vehicle just behind the front wheels. When the car begins to slide I rotate and start looking out the side window at the road in front of me. The rear of the car slides but the driver doesn't (in my perception). Now tell me why I am wrong.

[crs2012]

Greetings!

Just my 2 cents on the spin / slide build discussion....

Technically speaking... a spin and a slide are fairly similar motions as you described... The only real difference between
one over the other is the amount of centrifugal force due to the reference point of center. Both options are actually
spinning around a center point... One version you are sitting nearly on top of center of rotation, and the other option, the
front of the sim is at the point of rotation. Which one gives better emersion? Both, would theoretically achieve same
feeling of the effect, all you have to do is adjust the speed of rotation of yaw effect to compensate for the difference of distance to center.

https://en.wikipedia.org/wiki/Centrifugal_force

Centrifugal force (from Latin centrum, meaning "center", and fugere, meaning "to flee") is the apparent force that draws a rotating body away from the center of rotation. It is caused by the inertia of the body as the body's path is continually redirected. In Newtonian mechanics, the term centrifugal force is used to refer to one of two distinct concepts: an inertial force (also called a "fictitious" force) observed in a non-inertial reference frame, and a reaction force corresponding to a centripetal force.

The term is also sometimes used in Lagrangian mechanics to describe certain terms in the generalized force that depend on the choice of generalized coordinates.

The concept of centrifugal force is applied in rotating devices such as centrifuges, centrifugal pumps, centrifugal governors, centrifugal clutches, etc., as well as in centrifugal railways, planetary orbits, banked curves, etc. These devices and situations can be analyzed either in terms of the fictitious force in the rotating coordinate system of the motion relative to a center, or in terms of the centripetal and reactive centrifugal forces seen from a non-rotating frame of reference; these different forces are equal in magnitude, but centrifugal and reactive centrifugal forces are opposite in direction to the centripetal force.

Short answer...

Theoretically both options are good for feeling...

But

Both options vary greatly in cost due to time, materials and motor strength to achieve the same thing.

[yokoyoko]

Both options vary greatly in cost due to time, materials and motor strength to achieve the same thing.

Good point.

I don't say that the way I described to realize a "traction loss" is the only to achieve the goal. I thought about the behaviour of a real car during oversteering. The front wheels keep the adhesion while the rear wheels lose adhesion - due they have to transfer two forces! --->
http://en.wikipedia.org/wiki/Circle_of_forces

The only real difference between
one over the other is the amount of centrifugal force due to the reference point of center.

That point motivated me too to go the way with two bearings. As I can realize higher "forces" in the seat.

[RacingMat]

> I will go with the central hub design
Yeah ! nice to see new experiments !!! I'll keep support you if possible

Spinning/sliding should not be significant as your mind will probably be fooled by the feelings while your attention aims toward driving the car in the game.
But IMO there's a difference when you're sitted on a desk chair spinning versus feeling lateral forces pushing you during traction loss.

[RacingMat]

here's a spinning 3DOF sim in video


I'ven't found further information about it on the internet, maybe you could ask the author via youtube ?

[yokoyoko]

It is depending on what you like but in my opinion the profile of the shown video needs some tweaking. The spin is active if the car isnt sliding. It seems like alot of lateral forces is used for this effect too!?

May be he is using "map orientated" yaw... but also in this case the system kind of overshoots (north, west, south, east).
Great found anyways!!!

Edit: for such a setup i would have a look for a wheelchair motor with wheel attached. You can find these items in ebay very often. The motors have 24V ... two rolls in front and the motor with the wheel in the back.

Like this:
But how to get feedback to this? ... Mat will find out

[RacingMat]

I agree that this permanent turning looks a bit like a carrousel !

I was wondering if this permanent turning was caused by the optical sensor loosing the reference ?... or, as you said Yokoyoko, the profil ...

The author promised to give more details in the next weeks !

[vicpopo]

Hi Guy's,

Was it possible using the wheel as input and using it for turning the simulator?
I remember that i tried using brake pedal input joystick info to tilt down the simulator.

[yokoyoko]

Was it possible using the wheel as input and using it for turning the simulator?

Yes this is possible. I dont know how to from memory but you will have to setup something in the extractor and can use the wheel or pedal input for effects in the converter after.
I think it is explained in the manual. Otherwise i will make a tutorial later the week.