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EnduranceRC

Alternative r/c control -> PPM input

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Hi everyone,

I am currently working on a new device which will allow alternative input methods to be plugged directly into the buddy box of an r/c radio without the need of a pc. Over the weekend I created a prototype device. The device will allow a user to modify a joystick or custom made device for PPM output.

I have created a video of the prototype system. You can see it here: http://www.endurance-rc.com/media/prototyp...JoyPPM_beta.wmv

Let me know what you think, suggestions, etc. One thing I am thinking about is a power source. What would you guys perfer? Thanks!

-Phil

Edited by EnduranceRC

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HI

Not sure I understand how this works.

does it create a 5th channel on a 4 channel system.

When you say Buddy box is this another Tx used as a trainer through the a other Tx?

What I am looking for is to add a gyro to a goggle head set so when you mover your head the pan /tilt camera will track it that direction. Any ideas?

Thanks

3R

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Not sure I get it either, do you mean the joystick is supposed to be disassembled and the pots connected to your device? It's what I seem to see in the video at least :unsure:

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You mean instead of say Gyrocontrol connected to the trainer port, you connect a buddy box which is then connected to your device. This would allow a user to connect a PC "flight" joy stick to it. The joystick transmission flows through the buddy box and THEN to trainer port of radio thus allowing a user to fly using this method? Do I have this right judging from your video? If so, very cool stuff! :lol:

Edited by JMS

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This seems to me like the same kind of device people have been using for connecting headtrackers to radio transmitters?

i.e. does it work like this:

Tx -> trainer_port_PPMout -> [Your device] -> trainer_port_PPMin -> RF out

I think you would need to rewrite the whole digital transmitter GUI for your project. For example you have to program in your device support for trim, reverse, exp, EPA, sub-trim, possibly mixers and stuff. You're going to need a display + GUI to let users change all these parameters, wouldn't you?

BTW I've done some tests with PPM generation on my Hitec Optic and I can tell you that this way you can easily extend the number of channels supported by your transmitter. I tested 8 channels on Hitec.

As for the power supply - you have your transmitter voltage on trainer port socket available (at least in some Tx models).

Edited by mieczotronix

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Yeah you guys got it. My first idea was to take a joystick, remove the guts while leaving the pots for each axis and then wiring it up to this. Its not limited to a joystick however, it was just my first idea. I don't know how it could be used for a headtracker though.

mieczotronix,

I will add some trim pots for endpoint and center adjustments but I dont plan on taking it any further than that due to complexity. It needs to stay low cost. I think some radios will allow the trainer to pick up these settings but I am not positive.

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OK so basically you're making a TX encoder... couldn't we simply take the board from a cheapo TX, wire it to the joystick's pots, and take the PPM output? :unsure:

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it's quite funny to read this, since a buddy and I are currently working on a similar project:

USB device (target) <-- translater --> PPM connector <-- trainer port of Tx

Whereby for the translator we are using an Atmel AT90USB1987 - since it offers both the USB Host portion + SDK and ton's of serial interfaces.

Keep me posted on how you get on with your implementation.

relee

PS: I always thought that using the Tx build in sticks su..'s. It's simply not intuitive enough - therefore I've started this project first with a regular Joystick (Thrustmaster) - but over the time I've found an even more intuitive device, called the SpaceNavigator PE (costs around 50 Euro) with 6 axis () - comes out of the 3D construction world. Extreme precise device

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Kilrah,

Sure that is possible. It's also possible to wire the joystick up directly to the radio. There are plenty of options for alternative input, however, Im sure not everyone would want to mod their radios or buy another to tear apart. The point is to keep your radio stock while allowing for other input methods. A bonus is it could easily be swtiched between radios.

I like to build tools/devices that I need for myself. If others can use it and get to the end result quicker then it makes me feel good. There is always another way to do anything...

relee

No problem. I will post all videos/images here. As of now its still in the same state so nothing to update as of now. I have some input on power and it seems like battery is what most are interested in.

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Hey guys,

Small update on this project. I have purchased a cheap joystick and Im in the process of tweaking the pulse to movement ratio. I will most likely post a video tonight.

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very nice project,

i can't imagine how cool should be fly FPV with HT and Joystick in a confortable chair,

let's go furrow skies in group! :D:D:lol::lol:

e31811dc7.jpglearjet4fa9.jpgdsc01214go8.jpg

Edited by wallaguest1

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we belive in you, sure you succes in it XD

We w8 the video impatiently :P

i already was looking for a nice joystick haha :P

that one seems pretty cool: Sitek x52

but... how to control rudder ?

x52pf3.jpg

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I like the idea of being able to use this for a joy stick. I have a CH flight yoke set up I use with MS flight sim that I would like to try and use for FPV piloting.

Rudder control could be foot pedals or twistable joy stick.

Any way to get Force Feed-Back to work :D (hehe).

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Flight Sim Yoke ? seems nice too, and more realist for all planes,

the joystick seems just for jets and so on, right?

the problem with Flight Sim Yoke is that you need hold it strong in a table,

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I have the saitek x52 but I really didnt want to convert my $110 joystick. It should work the same though.

With the saitek, you have x,y, throttle, and the joystick can "twist". Rudder would be possible on the saitek.

Ok so now the bad news. I have it working fairly well now but I have no camera. My girlfriend swiped it for a business trip.

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and will be possible to use the buttons in the joystick to (for example) switch beetwin two cameras? or any thing like that? switch from menus in the OSD... take photos with a digital camera... and so on? ^_^

im so exited... even if i can't pay it haha :D :D

Edited by wallaguest1

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I think FF could work but you need a data downlink from the plane. Basically, what you do is you measure the current each servo is drawing and that should be proportional to the force for that surface. You feed that back into the servo for the joystick and you have FF! That will be something totally unheard of! A first.

Daniel

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or you could just measure how much vibration is in the picture with the use of a computer and some "simple" motion sensor code.. the more objects vibrate, the more feedback ;)

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The vibration method is too crude and imprecise I think. If all you want is just some vibration then that's okay but to have proportional force-feedback you will need something more sophisticated. I have the MSFF2 stick and I can see that you will need separate forces for individual axis. I think it can be done since the servo current will be directly proportional to the surface forces.

I think, maybe if we can have some hall sensors to see how much current each servo (usually FF only has servos for pitch and roll so that keeps it simple) is drawing, then send that data back and have the ground controller feed that back to the stick, you can in theory "feel" the forces on the plane - including stuff like cross winds which you normally would not notice except visually. So if you get hit by a gust, the servo should draw more power to keep the ailerons level, for example.

The other way would be to open up the servo and tapping the error feedback voltage from the position potentiometer. That might work too. I prefer the current sensor though, seems like a much simpler solution. Unfortunately, the MSFF2 needs a mains power supply but I suppose if you gut it and provide your own power, it should run off (hefty) batteries.

So - 2 hall-effect current sensors for the pitch and roll servos, onboard ADC to covert these current readings and a serial link to send that data back to ground. Then on the receiver side, controller to convert the data and drive the servos. Seems to be quite straight-forward.

Daniel

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problem with going by current is that just doing the actuating on the servo will cause force feedback. If your going with telemetry maybe using accelerometers would be best ;)

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