Thursday, October 3, 2013

Hobby RC remote for testing the Lawnbot!

I've been stuck indoors, unable to work on the mechanical parts of our robotic lawn mower.  I took advantage of this time and wired a Futaba FP-R127DF 7 channel Receiver to an Arduino Uno r3 and wrote a few lines of code to see if I could get it to read the signal from a Futaba T6XH-Super PCM1024 6 channel transmitter.  Was a lot easier to get the Arduino to display the signals than it is going to be for me to figure out what they all are.  This is a programmable aircraft/helicopter remote with settings for just about everything.  Ailerons, flap, Swash Plates and mixing of all the signals.  Wish it was a standard RC car remote!  It's going to take some research to program the transmitter.  With what I do know now, I believe I can get it driving the bot. 
 I started out the day knowing nothing about how to read or interpret rc hobby remotes.  I searched and found a real nice tutorial over at sparkfun.  Wasn't as complete as I thought,  but there is additional info in the comments that will help get it working with dual motor controllers.  The actual page is: https://www.sparkfun.com/tutorials/348
 BTW, not sure if the Raspberry Pi running Raspbian allows for enough time slicing in the multi-tasking to be able to poll the serial ports (usb)  for an rc transmitter combo.  I originally started using the Pi to program the Arduino as I always do.  When I opened the serial port monitor to view the signals, the cpu bogged down and brought the entire system to an absolute crawl at 9600bps.  Made it unusable.  Was forced to bring out another machine with an OS that I loathe! If it weren't my kids, I would install linux on it.  If you were to really delay the polling, you may be able to read it, but I would really check into other OSs or distributions if you want to use it with the Pi.  This is one of the reasons I  will be using the arduino with the Pi on this robot. 
 Tomorrow I hope to post some new updates on the chassis.  At the latest I hope to have something actually moving my the end of next week!  
 I also updated the current hardware page.  This is really starting to run together.  I think it's time to separate the parts by project.  That way if you are trying to duplicate something,  you will know exactly what I  did it with.