Joystick mods

[Dordai]

Team 1727 has been having problems with our chicklet at chesapeake and we would like to find a more reliable solution to the poor quality white joysticks in the kop. Our problems with the chicklet began when we found that none of our 7.2v batteries for it that we brought would hold a charge. It was probably from most of them being used on previously with the 12v backup batttery charger from IFI that doesn't have any sort of cut off to stop charging them. Not directly the chicklet's fault, but it's another point of failure introduced into the control system that is necessary with the chicklet.
After battery problem was fixed, the chicklet outright died and refuses to recognize any compatable usb joystick we have tried. It stays with the red light on and doesn't switch to orange or green. If anyone has any suggestions, feel free to give me some ideas.

So the main reason that I created this thread was to see if any teams have had experience converting a modern USB joystick to a gameport connector. I tried with our logitech attack3 joystick at the competition but it was built so that it gave 127 values in the upper left corner, which would not work. Also, there was a lot of jitter on the signal from the pots. The value that the OI was showing on dashboard jumped around from about 160 to 175 when the stick was centered and no one was touching it.
I have heard a lot about the old CH Flightstick sticks that used to come with the KoP. I saw on their site that they still sell them, but they use a USB interface now. They do sell spare parts and the internal gimbol mechanism and pots look similar to the ones in the white sticks in the current KoP. Has anyone ever tried to modify the new Flightsticks to be able to be plugged straight into the OI? I don't want to spend $90 on one of those sticks and have it not work like the attack3. Logically, to me it seems that these might have a better chance to work because it looks like the design was not drastically changed when these sticks were switched from gameport to usb.

[lukevanoort]

I have no experience modifying USB sticks to work with gameport ones, but I did play around with modifying the white KoP sticks in an attempt to make something useful out of them, and the results was this joystick: http://www.chiefdelphi.com/forums/sh...ad.php?t=62582

If you don't need the buttons, it is a great mod. It drastically improves the white joysticks' feel and centering. I personally like joysticks with very strong springs, so the spring mod may be a bit much for some, but just getting rid of that massive handle makes the joysticks vastly better.

[Racer26]

1075 has made a similar joystick mod to the crappy KoP joysticks... our 2003 KoP CH's were getting pretty shabby lookin', so we built an aluminum grip for the KoP ones. Works pretty well, i think we added a plate to it to attach some switches to for gear shifting and such... also, we made a steering wheel out of a pot and the 8" (i think, might be 10") skyway wheels we used to get.

[Billfred]

Alternatively, consider 11's mod from 2006: http://www.chiefdelphi.com/media/photos/24801

One thing that 1293 did in the same year was crack open the base and add rubber bands meant for braces to the stock springs; the result, combined with a change from the stock handle to a shifter knob, was a much tighter feel--even without the knob, you could feel the difference for no money. (Come now, if you can't find anybody at your school with braces and rubber bands to spare...)

[Tom Line]

Be very careful cracking the joysticks open. As our team found out the hard way, of the 6 joysticks we opened, EVERY SINGLE ONE had completely different colored wires inside (and run through the DB15 cable as well). So if something breaks, putting it back together is near impossible.

Never again will we touch the inside of those joysticks. They are so finicky and easily broken that we are scared to even shake the things

[ZakuAce]

One of our mentors went out and bought a bunch of old computer joysticks and we tried to use them, but they were even harder to use than the KOP joysticks! Their sensitivity was way high, so it was almost impossible to control the robot.

BTW has anyone tried using the Ace Edge yet? I know it's expensive, but maybe someone was totally nerdy and tried it.

[Racer26]

Originally Posted by Tom Line

Be very careful cracking the joysticks open. As our team found out the hard way, of the 6 joysticks we opened, EVERY SINGLE ONE had completely different colored wires inside (and run through the DB15 cable as well). So if something breaks, putting it back together is near impossible.

Never again will we touch the inside of those joysticks. They are so finicky and easily broken that we are scared to even shake the things

This really irritated us... I can't believe a company would use basically random colors for the wires inside... We've been competing since 2003, and have one set of these piles of crap for every year except 2005 when we didn't compete since 2004. I don't think any two of them were the same this year when we tried to make a mod since our only two flightsticks from 2003 that we've used every year are getting to be a little bit shabby.

[SteveJanesch]

I've personally seen Luke's modified KOP joysticks and can tell you they're pretty sweet.

1533 has gutted USB joysticks and/or Xbox controllers for each of the last three years with good success. The trick we finally learned is to not worry about re-using an existing cable with a 15-pin end - they have infinitesimally small wires - but to use a male 15-pin connector and just solder the wires from it to the pots/switches you need on the joystick. It winds up being a pretty large bundle of wires, but the upside is that you can do your own color coding and dictate which controls on the 'stick you need and which you don't. The thing you have to pay attention to is the maximum resistance value of the pots themselves - if it's less than 100 kOhm, the minimum voltage won't get down to 0 at the end of the pot travel and you'll have to scale it in software. Finally, you'll need some sort of strain relief - zip ties or hot melt glue or some such thing - to keep the wires from getting pulled out of the joystick.

Good luck,
Steve

[Racer26]

The other thing 1075 has done in the past is to build a small Y cable that mapped the Y axis of joystick 1a to the Y axis of port1, and the Y axis of joystick 1b to the X axis of port1, for tank drive, since we didnt want to use the X axes of the joysticks.

[Shadow503]

I like ours, we've taken a game port Steering Wheel and wired it to work with the operator interface. I had to hard code an offset but besides that it works like a charm.

[thefro526]

Some how I always get stuck making the OI so this year I found this in my room and I'm gonna use it in Philly



Also I might integrate one of this into my controls for the operator(me) http://www.trossenrobotics.com/store...tick-100k.aspx I might make something like a Wii Nunchuck for the fun of it.

[DGrohnke1023]

http://www.chiefdelphi.com/media/photos/20728

That's a picture of our 2005 OI.
We have done the same thing with our 2 shiny new joysticks each year; rip the handles off and stuff the wires inside. This mod lets us drive with our thumbs, giving far better feel than using the whole handle.

This gives you better feel with out costing a thing. (Other than the time required to take apart the joystick. But that's offset by the fun of destroying something!)

[Racer26]

Cool! A Gravis GamePad... I remember those... wow... now I feel old.

[Shadow503]

Originally Posted by thefro526

Some how I always get stuck making the OI so this year I found this in my room and I'm gonna use it in Philly



Also I might integrate one of this into my controls for the operator(me) http://www.trossenrobotics.com/store...tick-100k.aspx I might make something like a Wii Nunchuck for the fun of it.

Very nice, let us know how well it works!

[Loubear]

I don't have experience personally, but for this years game, my team basically ripped apart a usb nascar wheel, and converted it for use with the game port. I think they simply hooked up the pots and buttons to their corresponding pins instead of going through the usb chip, but I'll go ask them.