Interfacing a PICAXE with an RC Servo
|test code 1.0||48 bytes|
|test code 2.0||330 bytes|
I have added a video to show the picaxe modifying the servo signal based on the output from a Maxbotix EZ0 (EZ1 version here at LMR). The following image is also from that setup. The new code is attached (test code 2.0).
A small, cheap and light-weight PICAX-08M can be used to interface/interfere with the signals sent from an RC receiver to a Servo, allowing for all sorts of autopilot-style projects with your existing RC toys/new projects.
I have been wanting to play around with some sort of flying and semi-autonomous robot for quite a while. The only problem for me has been the weight of the microcontroller(s) and sensor(s) to facilitate this on a reasonably small flying platform (small RC Helicopter etc).
I had used PICAXE-08M's in previous projects, and loved the simplicity (and the lack of weight) of their packaging (8-pin DIL). The thing that worried me was the processing speed/accuracy of the chip in an environment as physically "harsh" as an RC Helicopter being flown by yours-truly :)
So, a test was in order. I cobbled together the following circuit on a piece of vero-board (see main pic), downloaded a simple program (attached at top) to the 08M, fired up my RC Helicopter and...
The 08M was perfectly capable of reading the servo-control pulses, and repeating them. It did this in a completely transparent way, with no change to the handling of the helicopter (see video). As an added bonus, the Servos on my particular helicopter (LAMA V4) require a 5 volt supply, hence the simplicity of the above circuit because I can directly connect the 08M inline.
Now, it is up to you. Turn this into something really interesting (RC autopilot...).
If you are interested, there is a bit more information on this and some of my other projects over at my blog.