Playing 360 degree wheel games with a 270 degree wheel and vice versa

[DorkVonWaterfall]

(split out from the driving cab info thread by BadMouth)

Personally I'd like to see the MAME Devs hack it or someone to release an alternative build of MAME hacked to make it playable with limited rotation wheels.

in this Jakks Pacific TV game 
the game Pole Position  is playable with only a rotation of like 90 degrees, maybe one can use something like that?? 

[baritonomarchetto]

No, that would not work because it's digital input, not analog.
Arduino leonardo could be a hardware solution.

[PL1]

I wonder if it would be possible to build a firmware/hardware solution that would translate one type of input into another like the way that joytokey changes gamepad inputs into keystrokes.

Seems like it would be fairly easy to make a 360 degree wheel to 270 degree game converter that would translate optical transition right/left inputs to increases/decreases of either:
1. A potentiometer-style voltage output (for input to a game PCB/console gamepad hack)
2. A USB HID analog gamepad axis value (for a computer)

The main downside is that you wouldn't have any mechanical centering.

The tricky (impossible?) converter would be a 270 degree wheel to 360 degree game.   

Just spitballin' here, but maybe use some code that translates changes in the difference between the potentiometer voltage (0-5v) and center (2.5v) into optical transition (quadrature waveform) outputs.

In the large central portion of the range of motion (___|___ below), the outputs could correspond directly with changes in the voltage (i.e. each 0.05v increase/decrease = 1 transition right/left) -- no transitions when the voltage is steady.

At the outer portion of the range of motion (*** below), quadrature waveform left/right transitions are sent continually even if the voltage is held steady.

The further you go from center in the outer portion of the range of motion, the faster the transitions are output, kind of like using a potentiometer and 555 timer to control how fast an LED blinks.   

0v   0.5v        2.5v         4.5v   5v
 |***|_______|_______|***|

Like I said, just spitballin' here, but maybe there is an idea here that someone can refine/rework into a usable application.   


Scott

[Howard_Casto]

I'm working on a hardware solution that seems to do the trick, but I haven't posted anything because it isn't installed in my cab yet. 

Basically I rolled my own optical wheel and put the entire assembly inside a piece of 2 inch conduit pipe.  The entire wheel and assembly can be removed when not in use and there will be a plug that looks like a fake gauge put in the hole when it's not installed. 

The only catch is the steering wheel on your analog wheel assembly has to be removable (not a big deal, they even sell kits for many of the popular wheels) and there needs to be some empty space directly above the analog wheel to drill the hole for the optical assembly.  So on a converted cab it might not be possible, but on virtually all home made cabs you should be able to do it. 

[BadMouth]

I wonder if it would be possible to build a firmware/hardware solution that would translate one type of input into another like the way that joytokey changes gamepad inputs into keystrokes.

Seems like it would be fairly easy to make a 360 degree wheel to 270 degree game converter that would translate optical transition right/left inputs to increases/decreases of either:
1. A potentiometer-style voltage output (for input to a game PCB/console gamepad hack)
2. A USB HID analog gamepad axis value (for a computer)

The main downside is that you wouldn't have any mechanical centering.

The tricky (impossible?) converter would be a 270 degree wheel to 360 degree game.   

Just spitballin' here, but maybe use some code that translates changes in the difference between the potentiometer voltage (0-5v) and center (2.5v) into optical transition (quadrature waveform) outputs.

In the large central portion of the range of motion (___|___ below), the outputs could correspond directly with changes in the voltage (i.e. each 0.05v increase/decrease = 1 transition right/left) -- no transitions when the voltage is steady.

At the outer portion of the range of motion (*** below), quadrature waveform left/right transitions are sent continually even if the voltage is held steady.

The further you go from center in the outer portion of the range of motion, the faster the transitions are output, kind of like using a potentiometer and 555 timer to control how fast an LED blinks.   

0v   0.5v        2.5v         4.5v   5v
 |***|_______|_______|***|

Like I said, just spitballin' here, but maybe there is an idea here that someone can refine/rework into a usable application.   


Scott

There are a couple solutions for 360 degree wheels in the stickied driving cab info thread.  It's very do-able at this point.  At least for MAME.
Much more complicated, but the GlovePIE solution would likely work on a lot of PC games and other emulators.

Going the other direction is the PITA.  Pole position is the big one, but the game might not play half bad if there was just a way to reset the center point after a crash.
I have a lot of great memories of Ivan Stewart's Super Offroad so I put that one on the cab regardless.
After lots of tweaking it's fairly playable with a 270 degree wheel, but there is just something that is off and I can't do nearly as well as I would with a 360 degree wheel.

I have a pile of parts to attempt a swappable setup, but have never gotten around to it.
My biggest problem was the wiring to the buttons and paddles on the wheel.
I just did a molex connector under the dash, but I was never happy with it.

[PL1]

Going the other direction is the PITA.  Pole position is the big one, but the game might not play half bad if there was just a way to reset the center point after a crash.

If the central portion of the range of motion (blue) was calibrated to cover from one side of the screen to the other, the outer portion (red) would be like moving a mouse to the right after you hit the right edge of the screen.

No matter how much further you try to move it to the right, it takes the same number of left-steps to return to the center of the screen.

By turning the wheel all the way one direction, all the way the other direction, and then returning it to center theoretically the cursor position should be re-centered, right?

If it doesn't work by calibrating the wheel to the width of the screen, it should work by calculating the number of optical transitions in the full range of motion of the game and calibrating the blue area to cover that many transitions.

Obviously, this calculation would have to be done on a per-game basis, but once the information is verified and compiled it would be possible to use it in any other build.   


Scott

[Howard_Casto]

Well yes that would center it, but you'd have to do it manually because pp needs a re-calibration at every wreck, at the start of the race, and after every course is completed. 

The big problem though is that the games don't feel right on an analog wheel.  Pole position of course isn't one of those cases, but the off road games where you turn the wheel multiple times to steer... it just doesn't work. 

[PL1]

True . . . and some people choose to play Star Wars with a trackball instead of getting a yoke.

It's not the best way to play it, but it's good enough for them.   


Scott