Raspberry Pi
 

Hi All, Im trying to think of a practical application in RC for a Raspberry Pi. I was thinking of some sort of transponder/decoder combo. Im not a coder but want to give it a shot with either Python or even scratch.

I like the idea of "easy lap timer" software (google it) but don't want to use a cam. Any ideas?

the Raspi can easily be setup with an infrared receiver. If you can make some sort of infrared transmitter that emits a unique signal and get them to talk every time the 'line' is crossed then that's the solution.

Subscribing to this thread...

the pi has a connectors for camera too
which could be used to make some awesome videos

camera $25
http://www.newark.com/raspberry-pi/r...rry/dp/08X2023

vid instructions
http://www.raspberrypi-spy.co.uk/201...camera-module/

@ mikeygar - Hmmm..... I did see a project that made a Pi into a remote control too. We'll have to think about this a bit.

@ffejrxx - Great idea as well. Maybe incorporate some sensor data. Speed, temps if possible on an HUD?

Yes, if you research how to use an apple remote with a raspi, you will find that it is easy to get an IR receiver working with it. I use raspbmc on mine with an old apple remote and it works fine.

I guess the easiest way to get it done is to run Raspbian as the OS since it's pretty user friendly and start from there.

Just a thought - if you can come up with the circuitry for an IR transmitter, you can copy the signal transmitted by your TV remote, say #'s 1 to 0 and assign those to transponders 1-10. That way, at least you can test the lap counter software using your tv remote without having to have actual transponders running.

Once that's done, then work can be done on making the IR transmitters since you've established preset codes already.

Also, some sort of pre-registration of the allowed transponders should be in the software in case someone points a TV remote at your timer and comes out as 'unknown' in the lap timing results.

showing a throttle/steer position would be a great add if its possible to take a pwm input

maybe a gps location/speed/altitude would be a fun add too

Ill look up the tv remote and draw up a schematic. Anybody code Python? Not sure if scratch has the hardware capability needed.

Pre reg would be a requirement. Im wondering if we can trigger a checkpoint pass in another way other than IR. Im thinking a magnet or something, then retransmit the time back to RPI using WiFi or ir.

I wonder if any work has been done with RFID tags on the Pi.

Ive been thinking about speed and a way to calculate it. GPS may be expensive. I think one of the requirement would be to keep it relatively inexpensive.

Not sure about scratch but the raspi has a built in IR library and there is a debug command you can use to parse the IR codes received by the IR receiver. Though you are correct, the GPIO pins of the raspberry can be configured to receive/transmit almost any type of signal, it would require making a decoder loop would require another breakout box connected to the raspi.

Check out TimR by DCD designs, one of the more popular lap timing devices out nowadays. They run on IR and have their own proprietary IR transponders for lap timing. The receiver box can be placed anywhere on the track, which is self powered and connects to a PC or mac via bluetooth. I've seen the pro on-road drivers use it during practice and it works really well.

Another option would be motion detection using a sensor. Good if you're the only one running on the track though but another easy way of hooking up something to the GPIO ports.

https://www.modmypi.com/blog/raspber...tion-detection

Ive seen that one. I guess I want to see it working to understand how it works. I think there are so many options with this. I was thinking about putting the Pi in the RC. if we need to add a bird that would be OK although the weight would add up. We could add another pi externally as stage 2 to maybe track multiple cars. I'm still trying to think of how we can register a lap pass. So far we have iR, Possibly a magnet, and maybe RFID if its possible.

One of the other thing I was thinking about is the capabilities to also control the server and speed control are definitely there. That would be another stage.

There are also all sorts of sensors you can add to these things for temp, rpm, speed, and gps, camera if cheep enough.

I need to put them in order of priority. Pi announces another mini board the other day too. From what I understand it may expand the io capabilities. Lets see what happens with that when its released. Until then, Im going to work on what I see is out there. Your thoughts?

Hmmmmmmm..... Sounds like how a mouse works.

This may be possible if the Pi Controlled the steering and throttle. Keep the ideas coming.

Definitely, the raspi can be installed in an RC and powered through the receiver, but for anything smaller than 1/8th scale, it would alter the balance of the car too much. Controlling and programming the ESC can be done for ESCs that allow on-the-fly programming such as the new Sanwa ESC, but then questions on how to send commands in a user friendly manner come into play.

Controlling the servo and ESC are achievable, since signalling is PWM which the GPIO supports but if you have a modern era 2.4 controller, why would you want to do that, unless you want to make a car that runs a pre-programmed route which is repeatable.

There are many breakout boards that can be connected to the pi, all doing different things, but doing so would require a few different boxes connected to an already large size for even an 1/8th scale car. I guess in order of priority, if telemetry is important, then the breakout boxes handle the different sensors, a micro wifi adapter on the pi handles transmission and a base computer receives and compiles the data into a readable format. The resolution of the results may be an issue since am not sure if it can handle polling 3 or 4 different sensors in half or fifth of a second intervals and transmit it almost instantly. 1 second polling might not cut it unless your track is really huge and a rough graph is acceptable.

If it can be done, do note that if running wifi, it will have to be 5ghz since most, if not all modern radios run on 2.4 ghz. That might be a bit of a problem for the pi since the wifi adapters I see almost all run on b/g/n which is 2.4ghz. So this may cause interference with the radio control.

If magnet will be used for lap timing, then you can only time 1 car at a time since multiple magnets on different cars will all read the same. RFID is possible, but you would need to create a decoder loop which will require additional hardware. If cost is a concern, IR is the way to go. I got my IR receiver for less than $2. No additional hardware needed as i plugged it into a ribbon cable I had which was connected to the pi. But IR is only 1 way and even if IR can register a 'pass' on the line, I don't think that it can handle multiple data transmission in such short a time, though it can be done but it takes more time to transmit the data than the time it takes to make a pass.

I think you have to limit the scope of your project, define your requirements and set your parameters. It's a good idea, but at least for me, aside from a creative challenge, has the potential to become too complicated by wanting it to do too many things.

If you want to control a car, check out this kit: http://pi-cars.com. Has all the stuff you need, and instructional on programming it as well :-)

I've got a few Arduino/Raspberry Pi projects underway... One is to power a LED Dot matrix panel showing the current Heat and Round. If your track uses RC Scoring Pro software, it continually writes all it's data to a XML file. This is intended for upload to liverc.com to show live results, but there's no reason you couldn't read it and parse it for display. A live scoreboard seems a little more complicated, but that's also on the list. There's some stuff on embeddedadventures.com for this.

Someone already built a homemade transponder/decoder. There's a thread on it. He's not using a Pi but some other microprocessor.

I was thinking you could set one up with a photo eye for timing r/c drag race events (I've seen some similar pinewood derby projects like this). Might try messing around with that too.

We use Alycat at our track and in the past couple years, there was a lot of interest in having scoreboards (primarily overseas), but the scoreboards are ALOT of money. Someone came up with the idea to buy a large screen tv, (since they are cheaper than a scoreboard), and turn it to be portrait, and the real time race is shown on it just like a scoreboard. Currently Alycat has up to 3 different screens( RM, Cutdown race screen, and Scoreboard).

I was interested in the PI to use as a media player for my home tv. I may still do that.

Ok, Thanks for the input cdwilliams1, I started this thread after reading the thread you mentioned. It appears they had already designed something for reading standard RC4 transponders which is great. I was thinking of something a little different with a Pi. I think it would be great to do that but would be easier and most likely just use the Pi. Thanks for the input and keep the ideas coming.

JimmyG, This could most definitely be done pretty easily. Im already using the Pi for remote display and virtualization thin clients. Cool stuff. You could also use it as a web server and display the xmls that cdwilliams mentioned. I guess there are many options with this. Even as easily as using relive.com to display the race and results.

Ok, Started getting familiar with the Pi this week. Anyone fluent in Scratch or Python?