7 replies to this topic

[awjennin]

THIS IS A FEELER - PLEASE RESPOND IF YOU ARE INTERESTED!!! OR HAVE ANY SUGGESTIONS!!!

I have started prototyping a new shield for my personal use, but am considering building it in a few short runs if anyone is interested.


THIS will replace your RC remote, and your receiver. It will give you much longer range, the ability to configure it, detailed sensor information, and the ability to use a small PS3 controller instead of the big bulky and heavy RC remote. It will consist of a remote board that goes in the air-chassis, and a board that will go in a ground-station.


There are two boards per kit - a BASE(command) and a REMOTE(uav). The boards are Identical - but are populated differently based on their desired purpose.

BOTH the Base and Remote interface to the ARDUINO MEGA style boards and have...
- DNT900 long range telemetry radio which offers up to 40km range with proper antenna's - with a data rate of 115200k! If you are interested in slightly less range, you can crank the baud rate up to a fast 500k!
- RGB status LED(s) for feedback
- External interface connector that allows you to send +5v, GND, Serial TX/RX, 2 analog IN's, 2 PWM OUTS, and 4 digital I/O's to any other devices (gps, imu, other sensors)
- 8 Dedicated & powered connections for servo's (servos! and esc's!)
- Power input connection for easy interface to a BEC to power it (no more than 5.2 volts absolute max in)
- U.FL -> SMA to interface standard antenna's to the radio module


The BASE has... PS3 CONTROLLER! (whoops, spoiler!)
- USB port on it which will allow for a completely new kind of control! a PS3 controller can now be used to control your long range UAV! it is a fantastic interface because the 10 buttons on it are all pressure sensitive and will read out a value between 0-255. There are three buttons with boolean output, two triggers with pressure sensitivity, and two thumb joysticks! There is also two adjustable output RuMbLe motors (high/low), and 4 LED's that can be used for feedback.
(My code is based off the fantastic work at http://www.circuitsathome.com/)


The REMOTE has...
- video switching, so up to two camera's can be interfaced with this board, and you can remotely switch which camera is being broadcast by your video system!! typically, I for-see a tilt compensated flight camera, and a camera pointed strait down for observation. Then they can be alternated via the SELECT button on the PS3 controllers!
- Pressure/Temperature monitoring on I2C
- (the external connection ports are for you to interface your own IMU and GPS to the board - everyone has their own preference!)
- (the 8 servo connections will allow for servo's or esc's!)



CODE will be open source - much of it is adapted from other open source projects, and credit is given in my code.


PRICE is not set. Once I receive my prototype boards and test them I will be better equipped to list the price. As a complete solution, it will cost less than two of digi's Xtend radios (at 380 per pair)

please let me know who's interested! 4 prototype boards have been ordered, and I will post pics when available


((teaser pic))

((remnants of my proof of concept))






THE MAIN SITE IS
http://diydrones.com...source=activity

Edited by awjennin, 28 November 2011 - 08:16 AM.

[Kilrah]

Pretty fun if you intend to fly your aircraft in assisted mode... but manually flying one with those awfully imprecise joysticks is a nightmare

[awjennin]

For my edification, are you aware how many steps are available in the X and Y directions on a standard remote? The PS3 controller gives 255 steps, and that is mapped into 180 steps (for the servo's). they can be a little imprecise, but a smoothing algorithm should help that. I wish they had a little more defined feel to the X-Y directions on the ps3 control sticks, but its not too bad.

When you say "assisted mode" i assume you mean assisted with a gyro or something of that nature? (forgive my unfamiliarity with the terms)
The board will stay open source, and it will have IMU integration built in, so it should fly quite stably. Also, i have built in video switching, as i intend to FPV.

Thanks!

[Devonian]

Somewhat similar to this...
http://www.rcgroups....d.php?t=1543898

[Terry]

By assisted I think kilrah means any auto pilot system that assists the flight path. For me the idea of flying with my thumbs dose not appeal, I guess its down to the fact that I have been flying sticks so long. Maybe kids brought up on game stations may find it more natural but I agree with Kilrah that with no help from software or auto pilot it will be a nightmare. Taking aerial photos on a gusty day can be hard but with thumb controls I would think impossable.

Just out of interest what frequency are you using?


Terry

Edited by Terry, 01 December 2011 - 12:15 AM.

[Kilrah]

For my edification, are you aware how many steps are available in the X and Y directions on a standard remote?

The standard is 1024 steps per channel. High end systems of the past 3-4 years use 2048. Servos on the other hand rarely can resolve that many, the average being more like 200-500, with some significantly fewer.

The PS3 controller gives 255 steps, and that is mapped into 180 steps (for the servo's).

The "initial" number of steps is OK. What's not is the backlash, imprecision, bad recentering of the PS3 sticks, and bad ergonomics of trying to steer these small things with short travel with the thumbs. It's pretty much impossible to do a movement on the X axis without also significantly moving on Y, and vice versa.
They may give you 256 steps on your ADC value, but once filtered enough to end up with something decent that doesn't jump around, you'd have to be happy if you have 16 of them left...

I've been working on a project for a camera remote control where we considered using those sticks because they were the perfect size for the product, but had to ditch them quickly due to that. No way to control a smooth zoom with them.

When you say "assisted mode" i assume you mean assisted with a gyro or something of that nature? (forgive my unfamiliarity with the terms)

Yeah, I mean that you wouldn't be directly steering the control surfaces, but would rather be telling a full time autopilot "go left" and it would take care of actually steering the control surfaces with more precision to achieve the new flight direction... a bit like the very simplified controls in a PS3 game

There is a guy a couple of years ago who had taken a PS2 remote, emptied it, and integrated a microcontroller to generate a PPM stream and a small UHF LRS in the remote's case, aiming to have a less bulky remote to carry around. Looked good and clean, but AFAIK it got forgotten in a drawer after the first try

Edited by Kilrah, 01 December 2011 - 09:57 AM.

[awjennin]

I have made some updates!


There will be 16 servo connections, and they will have 12-bit resolution (4096 steps)


Kilrah, The USB will now allow you to hook up your high-end USB enabled transmitter to the dreamshield instead of the PS3 controller (if you prefer - and I assume hard-cores and purists would prefer). And yes, the IMU and GPS should help it hold its position quite well. The IMU im using is a 3 axis accel, 3 axis gyro, 3 axis mag. It works quite well, and has been used in a very impressive and stable quad-rotor design that i saw a long while ago
.
Terry, The radio can output up to 1 watt in the 900MHz range, pushing 115200 baud


Thanks for the interest!

[Terry]

OK thanks, 900MHz is used by the mobile phone network here so is a no go.


Terry