Build Your Own Arcade Controls Forum

Main => Main Forum => Topic started by: Trimoor on January 23, 2005, 04:53:49 pm

Title: Cheap analog joystick idea
Post by: Trimoor on January 23, 2005, 04:53:49 pm

There are plenty of people around here who really want an arcade quality analog joystick, but can afford to buy one from Happ.
Why not take a lesson from a classic console, and use hall effect sensors?

I am, of course, referring to the Dreamcast.
The analog stick from the sega brand controller uses four hall effect sensors and a magnet to read analog data.
The idea would be to simply place these four sensors underneath a regular digital joystick, and glue a small magnet to the end of the joystick shaft.  The interface could either use a DC->PC adapter, or you could directly wire the sensors to the game/midi port.  Windows should map it to a regular joystick device.

To use it, configure MAME to use the analog joystick device, and tell it not to use the digital switches.  The analog part of the stick is all solid-state, so it wouldn't affect the digital movement at all.

I would try this except for one problem...I'm using all of my Dreamcast controllers.  If you have a sega brand controller you would like to (cough) send me for the sake of this project, go right ahead.  Or else someone out there with a spare controller might try this themselves.

Let me know what you think.

Title: Re: Cheap analog joystick idea
Post by: brandon on January 23, 2005, 08:10:43 pm

I was thinking about something like this too because there really doesnt seem to be many decent alternatives other than the $100+ happs stick.. the only thing I wonder about is whether or not a really digital stick has enough range of motion to make a decent analog stick..

Title: Re: Cheap analog joystick idea
Post by: allroy1975 on January 23, 2005, 08:39:26 pm

That seems like a great idea...it can't possibly be that simple though, can it?

Title: Re: Cheap analog joystick idea
Post by: NoOne=NBA= on January 23, 2005, 09:01:14 pm

It COULD, but probably isn't.
There are alot of variables involved that may make it more difficult.

What vertical range must the magnet operate within to make the sensors function properly?
How much travel is necessary to make the sensors function to full efficiency?
Does the joystick travel TOO far, or not far enough, to give it this full range without going outside the operating range?
What physical obstacles need to be overcome to mount the base onto the existing joystick, etc....?

Title: Re: Cheap analog joystick idea
Post by: Trimoor on January 24, 2005, 10:34:10 am

If I could find some discrete hall effect sensors, I could experiment and probably get this to work, but I have only been able to find digital sensors.  Anyone know where to buy analog HE sensors?  I tried digi-key, but had no luck yet.

Title: Re: Cheap analog joystick idea
Post by: u_rebelscum on January 24, 2005, 01:49:31 pm

Quote from: Trimoor on January 24, 2005, 10:34:10 am

If I could find some discrete hall effect sensors, I could experiment and probably get this to work, but I have only been able to find digital sensors.  Anyone know where to buy analog HE sensors?  I tried digi-key, but had no luck yet.

I got a bunch from Allegro (http://www.allegromicro.com/hall/linear.asp).  They had a minimum limit, so I have too many.  I need to check at home to see exactly what I have, but PM me if you want a few or four.

Note - if you buy them on your own, be sure to get the "linear" or "analog" Hall Effect sensors; most of the current ones out there are hall effect switches (ie: digital).


BTW, Allegro has some okay schematics on-line, too, explaining the diiferent ways to set up hall effect sensors relative to the magnetics.  AFAICT, DC pads use the standard "head on sensing, single magnetic", except in dual (on both sides of the stick).  Atari's Hall Effects used the "Slide-By Sensing", with the magnetic polls perpendicular to most other ways (the first of the two "slide bys" shown in Allegro's docs).

Title: Re: Cheap analog joystick idea
Post by: Trimoor on January 25, 2005, 03:42:06 pm

PM sent.

Title: Re: Cheap analog joystick idea
Post by: moonpatrol 4 lyfe on January 25, 2005, 04:46:40 pm

what if you found a way to physically attach the end of the joystick ontp the knob on the dreamcast controller? (or any analog controller for that matter)

Bill

Title: Re: Cheap analog joystick idea
Post by: Trimoor on January 25, 2005, 04:59:26 pm

It might work with a DC controller, but I'm going to try for a less messy hack.
Most analog joysticks have pots connected at the fulcrum.  This is not easy to add to an arcade stick.  If you know otherwise, let us know too.

I'll try to get this working as soon as [u_rebelscum] gets back to me.

Title: Re: Cheap analog joystick idea
Post by: Xiaou2 on January 26, 2005, 04:31:52 am

 Ok,  this dosnt make much sense.
 
 You say you want an 'arcade quality'  analog stick....

 Yet, you want to use a typical 8way joystick as the mechanism?

 I do not think you realize all the factors here.   

 A heavy duty arcade analog stick uses a huge rubber gromet to produce the resistence - and center the shaft.   It also has a trigger and additional buttons on top.  Most Built of heavy duty steel.

 An 8way has limited durability.  Its spring is barly able to return its light shaft.  The shaft has no triggers or additional buttons.   Excluding the shaft... the entire base  is light duty plastic) 

  The cost of a used real arcade joystick on ebay is arround 30 to 60$

 Add up your cost of:
1) DC joystick
2) DC to PC adapter
3) Happ joystick
add other hardware, tools, time...ect...

and you will end up
paying about as much for a hacky clunky mess.

 Esp bad will be if the sensors arnt alligned perfectly. 
This could cause weird positional output.

Title: Re: Cheap analog joystick idea
Post by: Minwah on January 26, 2005, 04:53:02 am

Quote from: Xiaou2 on January 26, 2005, 04:31:52 am

A heavy duty arcade analog stick uses a huge rubber gromet to produce the resistence - and center the shaft.   It also has a trigger and additional buttons on top.  Most Built of heavy duty steel.

 An 8way has limited durability.  Its spring is barly able to return its light shaft.  The shaft has no triggers or additional buttons.   Excluding the shaft... the entire base  is light duty plastic) 

I partially agree with your point, but not *all* arcade analog sticks are as you describe.  There are analog sticks with no triggers/buttons (batt or ball tops), and some are centred with springs.  And the housing of the Happ analog stick I have is plastic, the same plastic used on digital sticks.

I don't know about the feasibility of this idea but I would rather use a digital stick style analog stick (if it can be done) than a PC analog stick.  Actually, this is pretty similar to what a Happ 49-way stick is in a way...that would be a good stick to try hall effect sensors on since it has an analog-like throw, and maybe the sliding actuators could be used to mount the sensors/magnets.

Title: Re: Cheap analog joystick idea
Post by: Lilwolf on January 26, 2005, 08:44:11 am

Just add more weight to the bottom.  This will add your centering... gravity.

I'm still curious if I can find a way to get the analog dreamcast working through an arcade joystick.... But thats for my dreamcast cabinet... not my pc cabinet.

one last mention.  Analog joysticks on ebay can go pretty cheap.  But flight sticks mainly... Hard to find ball/bat analog joysticks...  But you CAN find them with hall effects joysticks. 

Anyone ever try and hack a halls effect aracade joystick to a dreamcast controller?

Title: Re: Cheap analog joystick idea
Post by: Minwah on January 26, 2005, 10:03:05 am

Quote from: Lilwolf on January 26, 2005, 08:44:11 am

Anyone ever try and hack a halls effect aracade joystick to a dreamcast controller?

Don't think you can...U_Rebel has explained why before I think...

Title: Re: Cheap analog joystick idea
Post by: Trimoor on January 26, 2005, 11:45:39 am

You might be able too.  I haven't looked, but the pairs of sensors on the DC might be connected together with resistors to provide a single analog sweep.

For your Dreamcast cab, try opening the controller and placing the joystick part under the 8-way.  Attach a little magnet on the end of the shaft.  Let us know if you try it.

For the rest of us, my idea is no longer to have a DC, but to use discreet hall effect sensors connected directly to the game port.  I requested samples from allegro, and if this works, we could have analog mods for less than $5.  The sensors don't need to be perfectly aligned.  This is what calibration is for.

Title: Re: Cheap analog joystick idea
Post by: Sephroth57 on January 26, 2005, 11:55:24 am

i have no idea what youre talking about... but umm keep doin what ur doin =P

Title: Re: Cheap analog joystick idea
Post by: u_rebelscum on January 26, 2005, 04:19:57 pm

Quote from: Minwah on January 26, 2005, 10:03:05 am

Quote from: Lilwolf on January 26, 2005, 08:44:11 am

Anyone ever try and hack a halls effect aracade joystick to a dreamcast controller?

Don't think you can...U_Rebel has explained why before I think...

Ya, I sort of mentioned the differences in this thread.  But it might be possible....

Some Differences

	atari [/b]	DC [/b]
voltage	(AFAIK) 12 V	5 V
num sensors per axis	1	2
Hall effect movement	slide by	head on (aka normal, aka most widely explained way)

Now, if you know DC's circuitly, and if its two sensors are in series (like combined pedals' POTs), and if you know DC normal output range, and if you can replace the sensors and/or magnetics on the 720 controller to match DC's output, and if you can wire this to the DC, hey, piece of cake. ;D

Going the other way (hack a DC controller into an Atari controller), OTOH, is much harder (aka "impossible").