Star wars yoke - can you use optical?

[mamerJ]

I've been looking at building a Star Wars yoke and was wondering if you need to use the 5k pots or if optical would work? Was anyone tried this?

J

[2600]

Assuming you mean in MAME, optical would "work".  Fire the game up and start playing with a mouse or trackbal. Same thing.

The real thing uses a 5k pot and the play would be more accurate with a pot.  The value of the pot depends on your choice of encoder.

So really it's up to you and how picky you are.  Many people play with a trackball and like it just fine, other's prefer a yoke.

[Minwah]

Somebody made a homemade optic-based yoke once...it looked awesome.  However, the creator said it did not play well since calibration was lost all the time.

So in short, you should use pots, not optics.

BTW I found the yoke project from this site somewhere, so have a look through the project examples or search the boards if you want to find it.

[mamerJ]

The sidewinder hack it is then

[ChadTower]

There is a reason they used pots rather than optical.  They function differently.

A basic optical controller only moves the onscreen object while the controller is in motion and has no way of detecting center.  That is why opticals are 360 degree steering wheels and spinners.

A pot based controller moves the onscreen object the entire time the controller is not centered.  It's an analog joystick.

Star Wars, with an optical yoke, would not function the way the game was designed.

[Minwah]

There is a reason they used pots rather than optical.  They function differently.

A basic optical controller only moves the onscreen object while the controller is in motion and has no way of detecting center.  That is why opticals are 360 degree steering wheels and spinners.

The exception is RoadBlasters.  That used the same optics used in 360degree wheels but the RB wheel is limited.

But one the whole I agree, you should always use the correct type of control if possible.  I suppose another exception is that people like to use spinners for 'paddle' (pot) based games - the feel is totally different but for MAME it does function pretty well.

[ChadTower]

The exception is RoadBlasters.

[mamerJ]

good point ... hence the good old spin the wheel driving games "super sprint"

[ChadTower]

Pole Position.

[Minwah]

That's a third case, though, where you have limited range of motion on the optic wheel.  The operation is the same, really.  No way to detect center, and the car only moves when the wheel is moving.  If you offcenter the wheel and stop it there, the car is not still turning, yes?

Well in the game the car is turning...but nothing is changing anymore (dunno if that makes sense).  You're right anyway, just I don't really know how it works exactly, because when you turn back to the centre, the car should straighten up (exactly).  What I mean is, I don't know why calibration isn't lost, except that in theory the amount of travel from centre to extent should always be the same...but don't know how that works in reality.

[ChadTower]

Well in the game the car is turning...but nothing is changing anymore (dunno if that makes sense).

[mamerJ]

yep ... or in games like super sprint and off road when the controller stops the car straightens out with out having to return the wheel to center.

[ChadTower]

That method really sucks if you just pause for some reason.

[mamerJ]

That's how those games work right? Then games like Pole Position and Need for Speed used more of the pot approach of turn 35deg and stop and it continues to turn.

[ChadTower]

Pole Position is optical, 360 degrees I think.

[AC.]

Let us know how you build the yoke.   I would avoid optical.
I've always thoght this one was interesting
http://www.twistygrip.com/

[Xiaou2]

 mamerJ,  no,  supersprint and pole position are both 360 degree wheels (spinners), that use optics.  The car does not auto straighten out... unless you crash.. then it may face you forwards.

 I have a TX-1..  that ive just recently got working.  Ive not competely tested this.. but,   there is an optical pedal unit on it.  My thought is that the game is programmed to know there are a maximum of like 10 positions till the limits of the
mechanical stop.  If you held the pedal down from boot-up till game start.. it probably will not make the car go.  But once you release the pedal, it will see negative 10 position reads... and auto adjust so that when you press the pedal again it will return to moving the car forwards.   A pedal 'AI' .   Again.. Ive not tested that yet, but it would make sence.

 As for a game like starwars, which used a pot..  its not programmed to calibrate a  position like that.    Its also does not work in the same way at all. 

 In an optical setup, playing a non-optical game:    If there were any frameskips or anything that caused a slight delay or missed poll in your mouse optics..  your ships cross hairs would be out of alignment... and no AI in the game to correct it.  Non-optical games do not count  opto bars, and auto correct if theres a problem.

 Pot games see an absolute pot value... which is rock steady and stable.  Even if mame dropped some frames, polling was a little off.. its ok, because the value of the pot reading will always dictate an absolute screen positon based on that reading.   The only thing that can mess this up,  is if your pot mechanically slips because it was not tightened.. or ,maybe you if you calibrated the pots incorrectly  to begin with.

 In summation:   
 

   If you build an optical yoke,  it will de-calibrate too often, and upset you very much.

 Now... Analog pot driving games can be controlled well with 360 degree wheels.. because even if they de-calibrate,  you do not have a need to return them to any position.   But, if you use a 360 wheel to play a game like spy hunter..  you will not have any buttons on the wheel...  which makes the already hard game just about impossible.


 Btw..  If you do make a pot based controller.. make sure to use Gearing. 
A large gear on the shaft, and a smaller gear on the pot shaft.  This will give the
pot more travel - and thus a higher resolution.   You will have smoother more accurate controll.    I tried a direct drive 'shaft to pot'  (no gears)  and it was
aweful.   Poor control..  and windows didnt even want to recognize it propperly because it wasnt moving the pot enough.

 You can usually find these large green plastic gear kits in local hobby shops.

[mamerJ]

Right so supper sprint and off road are optical and when you spin the wheel the car starts to turn, when the wheel stops spinning the car stops turning and continues to go straight in the direction it

[ChadTower]

40-20 would be 2-1, wouldn't it?