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Old Jul 09, 2010, 04:09 AM
five by five
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Panama City Bch, FL
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math... i think they mentioned that back in school or something...

after hooking up the meter, the throttle pot issue now makes sense. the aile & elev voltages range from around .5v to 4.5v or so. the throttle, however, ranges from 0.000v to 5.5v. it tops and bottoms out voltage wise well before the throttle stick reaches its max & min mechanical travels. so where it has maybe 160 of travel, only the middle 80 or so are usable. i don't think software is gonna fix that. =/

maybe i replaced it with the wrong pot..??? i guess what i need is a pot with 160 of usable rotation. even with the throttle travel cut in half, its still easily enough resolution to fly an airplane! hopefully this weekend i'll get something airborne!
-sj
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Old Jul 09, 2010, 05:41 AM
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Aberdeen, Scotland, UK
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Originally Posted by sonicj View Post
math... i think they mentioned that back in school or something...

after hooking up the meter, the throttle pot issue now makes sense. the aile & elev voltages range from around .5v to 4.5v or so. the throttle, however, ranges from 0.000v to 5.5v. it tops and bottoms out voltage wise well before the throttle stick reaches its max & min mechanical travels. so where it has maybe 160 of travel, only the middle 80 or so are usable. i don't think software is gonna fix that. =/

maybe i replaced it with the wrong pot..??? i guess what i need is a pot with 160 of usable rotation. even with the throttle travel cut in half, its still easily enough resolution to fly an airplane! hopefully this weekend i'll get something airborne!
-sj
Yup, looks like you nailed the problem.

You could also try physically limiting the range of the throttle slider (if you can) via a couple of stops or something......80% sounds well usable.

Photos.........

Ian.
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Old Jul 11, 2010, 04:30 AM
five by five
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Panama City Bch, FL
Joined Jan 2009
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pretty sure i just killed digital pin 10. well, technically, spektrum killed it i guess... i had ppm out (pin 10) connected to the trainer port on the dx7 and i recon i must have only clicked my heels 3 times instead of 4 before i unplugged the cable anywho, it WAS controlling servos on the other end of a spektrum rx, but due to my flawed shutdown procedure, pin 10 is a now flatliner according to the scope. seems to work fine on pin 11, so hopefully the rest of the 328 is ok! gonna order a spektrum module or just stick with fm for the time being since theres no practical way to use the trainer port without modifying the dx7 momentary switch to a latching (that i know of).

a quick cellphone pic to keep ian off my back

cheers!
-sj
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Old Jul 12, 2010, 06:31 AM
five by five
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Panama City Bch, FL
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found the problem with the throttle pot! i put the pots back in the wrong spots!
rudder uses a 45 pot
aile & elev use 65
and throttle uses a whopping 145
i went ahead and started rewiring the whole thing since i was already in there and wanted to make changes anyways. should be MUCH better this time around!
-sj
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Old Jul 13, 2010, 09:25 PM
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Panama City Bch, FL
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board rebuilt!

if you look at the first photo and note the solder points above a2 & a3 (a4 & a5), then look at the 3rd photo and notice the pin placement. annoying! i would rather have the board a mm or two longer (or whatever it takes) to get those 2 pins lined up with the rest of the .1" x .1" pitch pins. ohh well... at least they are accessible, just gotta be ghetto fab i guess...
-sj
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Old Jul 14, 2010, 12:31 AM
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Lookin good.

I don't know what's happened to HobbyKing's shipping. It's closing in on a month already and still no goodies. I guess that is where to OLD song comes from: Slow Boat To China. However, in this case, it's the reverse.

Are you going to make some type of box or housing for your Jstick and controller? I am still trying to decide how to hold the thing. There was a Swartzennagger(sp) movie where he used a remote helicopter control that clamped to his arm. Attached to his arm allowed him to work the stick without holding it. Probably all CGI, but it looked as if it would work.

Oh, well.
Y
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Old Jul 14, 2010, 09:38 AM
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Aberdeen, Scotland, UK
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Hmmm, arm-clamp........nice idea!

Maybe I'll design a pcb for this (Eagle PCB) so in future folks can download the artwork and get it made themselves. Sonicj's layour pics give me some ideas as to what shape/form it should have.

Nice to see more pics..........I'll be uploading to my web page soon.

Ian.
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Old Jul 14, 2010, 11:26 AM
five by five
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Panama City Bch, FL
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Originally Posted by Yorbid View Post
Lookin good.

Are you going to make some type of box or housing for your Jstick and controller? I am still trying to decide how to hold the thing.
thanx!

i was just gonna zip tie to my arm and swing it around like arnold. nah, i'll likely cut a piece of lexan / plexi to sort of match the base but with an extension on the back. i could fit everything inside the case, but it would be a tight squeeze and i personally would prefer the accessibility of the board & module mounted externally.

have you seen tarro's rig?

Quote:
Originally Posted by IanJ View Post
Maybe I'll design a pcb for this (Eagle PCB) so in future folks can download the artwork and get it made themselves. Sonicj's layour pics give me some ideas as to what shape/form it should have.

Nice to see more pics..........I'll be uploading to my web page soon.

Ian.
i considered making my own board, but it looked like too many holes to drill for a first attempt at a custom board. i really wanted to build it up from a bare 328 chip, but radshack didn't have any 28 pin sockets and im always messing up perfboards so i went the impatient / expensive route.

back to the custom board idea... from what i've heard, seeed studio is cheap, quick and does a great job.

i'll get some more pics up as it progresses!

the arm clamp thing got me thinking... it shouldn't be too difficult to adapt your code to the wii-chuck library!
-sj
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Old Jul 15, 2010, 04:42 PM
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the arm clamp thing got me thinking... it shouldn't be too difficult to adapt your code to the wii-chuck library!
-sj
Built in head tracking? I'm about to order a new arduino but was thinking about trying to use a wii chuck to add head tracking as well.

Charlie
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Old Jul 17, 2010, 10:14 AM
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Originally Posted by charlienofun View Post
Built in head tracking? I'm about to order a new arduino but was thinking about trying to use a wii chuck to add head tracking as well.

Charlie
should work. are you building a joystick too charlienofun?
-sj
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Old Jul 17, 2010, 10:21 AM
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change of plans for the lcd... i think im gonna use this 16x2 i picked up from jglenn! the reflective display should be easy to read in sunlight plus its HUGE ignore all the wires in the picture, i've currently got it running on 3 wires via a 74LS164 shift register but i'll probably add a diode & resistor to run it on 2 pins.
-sj
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Old Jul 17, 2010, 11:19 AM
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should work. are you building a joystick too charlienofun?
-sj
I really want to build one but I don't have a joystick. I have been to three different thrift shops looking for any serviceable joystick's also a used video game shop but store nothing so far. I guess I need to just get an old analog one off ebay.

I was checking this out the other day http://www.starlino.com/rc_transmitt...lerometer.html and got the idea to mix the two projects. I would try and use the board from a wii chuck as I understand its is a i2c device which is easy to interface with arduino.

Would be pretty neat with this design, considering you could also build rudder pedals and or a collective control for looking really silly in public! hahahah

Charlie
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Old Jul 19, 2010, 07:20 PM
five by five
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hey ian... are you using a voltage divider to input batt voltage? do you happen to recall the value of the resistors you used?

new LCD is partially up and running! im using a 74LS164N shift register with a parallel 16x2 LCD. the 74ls164n took the 6 wire connection down to only 2. a little (ok, a lot) more soldering work, but can save some loot if you are on a budget and don't mind the extra labor. LCD works fine with the example codes. just a few formatting bugs left to sort out.

Quote:
Originally Posted by charlienofun View Post
I really want to build one but I don't have a joystick. I have been to three different thrift shops looking for any serviceable joystick's also a used video game shop but store nothing so far. I guess I need to just get an old analog one off ebay.

I was checking this out the other day http://www.starlino.com/rc_transmitt...lerometer.html and got the idea to mix the two projects. I would try and use the board from a wii chuck as I understand its is a i2c device which is easy to interface with arduino.

Would be pretty neat with this design, considering you could also build rudder pedals and or a collective control for looking really silly in public! hahahah

Charlie
for some reason, whenever i go thrift shopping for a specific item, i'll never find what im looking for. if i go in with no specific item in mind, i usually find something cool i "need". last time, it was a near mint vintage gshock screwback (1984) for a whopping $3.

ebay had some decent deals last time i looked! do you need the rudder axis? if not, i have another saitek cyborg sitting here i might be willing to part with.... i was thinking i would eventually hack that one for dual sticks on a tracked vehicle since it didn't have rudder.

wiichuck & wm+ is easy to interface. just 2 wires + pos & neg. wonder if you could use the wiichuck as virtual collective stick? pull up for collective, twist for throttle! cheers!
-sj
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Old Jul 20, 2010, 07:00 AM
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hey ian... are you using a voltage divider to input batt voltage? do you happen to recall the value of the resistors you used?
Can't remember, but the easy way is to use a 10k pot that way you can trim it to perfection without resorting to modifying the software multipier.

Ian.
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Old Jul 21, 2010, 01:56 AM
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werd! got it working! ended up with a 100k on one side and 47k + 10k trimmer on the other. the 5k i had seemed to do a little better, but it was like a 20 turn monstrosity. i think you have your voltage padded down a lot lower than mine... im pushing 4.5v or so at the a5 pin with 12.9v going in at the screw terminals. i had to add a lot of offset in the software to get the voltage reading back into range of the trimmer pot. i was thinking, the higher input voltage should give me a little better resolution when i run on 2s packs...?

it seems like it updates the screen kinda fast... 3 or 4 times per seconds maybe??? the top line has a bit of flicker thats in sync with the flashing yellow led on the arduino. gonna go do some more research on driving these lcds... cheers!
-sj
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