Krusty's throttle project

[Krusty]

Well, I resurrected THIS thread here, but decided I'd post something here in the hardware and software forum instead.

I'm thinking of doing a long-term project, and building my own throttle unit. As I posted just recently in the thread above, I was looking for the link Gianlupo put out so long ago. I did a google search and found this:

http://www.simpits.org/articles/throttle_quad/throtquad.html

But I don't know if it's the same link. It got saved because it's helpful, though!

What I'd like to know (and maybe Roscoroo knows this) is how do you get a USB connection instead of an analog connection. For sure, I'll be doing testing in analog (it's easier to test, just wire it up and go), but eventually I'll want a USB connector on this project.


I don't have any parts or plans yet, just an urge to give it a shot. I think I know what I want, but I'm wondering how many axis you can have on a single USB device, because analog is limited to 4 axis.

Also if you have any resources on where (in the U.S.) to order pots and trigger buttons from, please let me know! Thanks!

[Krusty]

There's some things out there for folks making full-fledged simpits. One is a $40 USB board that has up to 8 axis and many buttons.

http://www.betainnovations.com/hardware/plasma.html

I'm not sure how much it's worth that if I'm just using it for 1 throttle unit with 4-6 axis in it.

EDIT:

New question: What's the difference between a rotary and an axis?

[HomeBoy]

Krusty,
I've done several projects like this.  I like to use the electronics out of Logitech sticks as you can pick them up really cheap and though the sticks themselves are complete crap, the circuit boards and drivers are very good.  In my latest project:

GamePort to USB conversion project

I used a Logitech Extreme 3D stick which has four axes (roll, pitch, throttle, rudder) and lots of buttons.  You could even put two "sticks" in your throttle and that will give you the eight axes you're looking for.

-hb

[Krusty]

Interesting. I always thought logitech had crappy circuits. Or is it not even using those, just using the USB port + wires + etc?

EDIT: I read your write-up. Interesting way of doing it. But you have to be sure that the pots were the only crappy thing in the logitech system. I'm not so sure. I'll keep it in mind.

My question is, though, what's the difference between a rotary and an axis? Like say I want to make a trim wheel for elevator, can I just put that on an axis input? Or does it go on a different input?

Also, are you limited to the number of axis that the stick had to begin with, or can you shoehorn more in on the same circuits?

[Roscoroo]

Krusty,
if the logicjunk boards will work ok with normal 100 ohm type pots, ill send ya a couple to play with if you want .
Ive got at least 6 dead wingmans laying around . there pots are junk but there boards are fine .

what you do need is a spare working stick befor ya start doing mods.
 At least go get ya a cheap saitec st290 pro  ...20-29 bucks .

for a usb setup you have to use a usb board in the stick . you can go from usb down to gameport, but not gamepost to usb unless the circuit board is designed for that .. the interupt timing/packets are different.

its easiest to use a board from another stick, then it is to start from scratch and go with custom aftermarket curcuit boards (there pricey ..you can buy a full ch setup by the time you purchase all this stuff and figure in time.)

Some Reading material befor ya get started . some of this is analog some are digital/usb
http://www.epanorama.net/documents/joystick/pc_joystick.html

 http://www.technick.net/public/code/cp_dpage.php?aiocp_dp=pinconjoy_pc_game

http://www.epanorama.net/documents/joystick/index.html

This page will give ya a idea what it takes to build from scratch .
http://www.flightsim.com/cgi/kds?$=main/howto/mind.htm

My best advice is dont rush the project ... gather the parts /study / and take your time .    trace all your curcuits ,pin outs, ect and make your own schematic .

[HomeBoy]

I assure you that LogiCrap stuff works just fine without their so called "pots."  [Those pots win the prize as the crappiest pots I have EVER seen!]  I have been running a hybrid CH ForceFX / Logitech FF 3D whatever in a similar way the Pro Pedals are done.  It works perfectly.  I certainly would not be afraid to use the PCBs.  After all, no moving parts, etc.  If it works the first time, it should work every time.  What's crappy about Logitech other than the pots, is their gimbals, switch housings, springs, etc.  And that stuff is totally crappy!

Here is that project:
FrankenForce project

One reason you might want to look at something a little better though (eg. Saitek Evo) is to get better programming software.  Logitech software is pretty minimal.  Saitek appears a good bit better.   I use Logitech stuff because I can pick up a Logitech stick for less than $10.

As for you question about rotaries vs axes.   A controller only has two types of interface controls:  buttons and axes.   [At least I don't know of any other kind]  Therefore, my educated guess as to what people mean by that is a rotary would be an axis that is controlled by a knob of some sort (something you have to turn) whereas an "axis" is just the basic analog pot  which could be a "slider", "rotary", "lever", etc.

Can you put a trim wheel on ANY axis?  Absolutely.  A pot is a pot.  Some pots are rotaries (twist them) and some are sliders (you guessed it:  you slide it).  Other than that, it's just a device that produces a variable resistance to the circuit.

As for adding axes.  If you can figure out a way, I want to be the first to find out.  I think I can safely say NO to that question.  I have never seen a joystick with more that four axes.  Of course, the CH Throttle Quadrant has six axes but you will pay $150 for one of those.  As you pointed out,  people make USB  controller boards used by pit makers that support various configurations.  That is probably the best bet if you really want to go beyond four axes.

Hope that gives you more decision power.

-hb

[Krusty]

I'm digging the lego throttle idea. I've got probably a thousand legos from 10-15 years ago. Some superglue on each piece and it's never going to come apart. The only problem I can see is that there'd be no resistance on the throttle arms.

So I might not do that. I want the throttle arm to stay put when I move it. I might just end up using a piece of wood with some "L" brackets screwed into it. I'm thinking 4 throttle arms (one for each axis), and maybe mapping 2 to throttles, 1 to RPM, and 1 to elevator, or 1 throttle, 1 rpm, and 2 different trims.

Hrm... can you map "zoom" to an axis? Not sure how effective that would be, but it would be cool

[SkyChimp03]

Originally posted by Krusty
I'm digging the lego throttle idea. I've got probably a thousand legos from 10-15 years ago. Some superglue on each piece and it's never going to come apart. The only problem I can see is that there'd be no resistance on the throttle arms.

So I might not do that. I want the throttle arm to stay put when I move it. I might just end up using a piece of wood with some "L" brackets screwed into it. I'm thinking 4 throttle arms (one for each axis), and maybe mapping 2 to throttles, 1 to RPM, and 1 to elevator, or 1 throttle, 1 rpm, and 2 different trims.

Hrm... can you map "zoom" to an axis? Not sure how effective that would be, but it would be cool

 make the box throttl lol

[Krusty]

I was trying to avoid the ugly look of the box, but I might have to grin and bear it.

On a side note: I got some CH Pedals (non-PRO, non-USB) and I had a question:

If, after the throttle, I wanted to wire these to USB, how would I do that? There's 2  different axis (one for each pedal) but somehow it is supposed to act as 1? How do these normally work? Do they average the inputs? If 1 is fully deflected, I'm assuming you get full deflection. If both are fully deflected, I'm guessing you get neutral. If both are partially deflected I'm guessing they'd cancel each other out partially. I just don't know, though.

[Roscoroo]

its one axis on the pedal  for the rudder .
This may in a single pot or a dual pot set up (in the dual pot they are married together and actually act like a single pot)


the toe brake models have a second axis for those . but in AH its either on or off
type signal used .

[Krusty]

How will it work with 2 pots on 1 axis, if the pots are going in different directions? Each pedal has a pot, but can both be depressed at the same time

[GunnerCAF]

Maybe this would be of interest.  Plenty of programable buttons and levers.

http://www.chproducts.com/retail/t_tq_twin.html

Gunner

[Krusty]

Yes, Gunner, that's the inspiration, but if I had $200 lying around I'd be forced to spend it on bills instead

CH is out because it costs too much. Always has, always will.

Hence my idea to build my own (total will probably be around $40 or so)

[GunnerCAF]

Krusty,

Nothing wrong with building one.  It sounds like a fun project.  I like the idea of using a used stick with new pots.  The hard part may be making the hardware, at least for me it would be.  I look forward to seeing what you come up with.

Gunner

[Krusty]

My main mystery is going to be how I make the throttles move with a bit of friction. I want them to move freely, but to stay where I put them (that is, I don't want to place the throttle at 60% and have gravity pull it to 100%).

On those 100k ohm pots, what's the resistance like? If you set it, does it stay there? Or is it loose like a combo lock?