Help selecting correct hardware for project

So I have a little project that I have been working on integrating into the open9x firmware for the turnigy9x and other clones rc transmitters. It works fairly well but it really is more suitable to an on vehicle device rather than in rc transmitter (partly due to channel count limitations).

What I want to do is read in 3x signals from a standard rc receiver, do math on them (some trig but I've got integer trig functions that work well), and then output 15x rc servo signals. The math is straightforward and can readily be done in mostly 16 bit signed integers (about 30 of these) with about 4 32 bit signed integers required for some of the math so as to avoid any floating point math. Size is at a premium so I would prefer to stick with something as small as practical. Ideally I would be able to set some of the parameters via some display interface or via computer without recompiling but for now I can live with hard coding most of them until I understand the hardware.

I've done a fair bit of C but most was math/internal functions, no real hardware I/O.

any thoughts on a good place to start? I had seen this: which looked quite interesting

thanks for the help Greg

I suspect a standard Arduino could do all of this quite well. The math is no issue even with an 8-bit processor because the long type is a 32-bit int. Standard hobby servo signals are also quite low frequency, so keeping 15 of them going at once should be doable. The standard Arduino has 14 digital IO pins, but the 6 Analog pins can also double as digital pins giving you 2 pins to spare for serial transmit and receive.

If you are new to Arduino I would start with something like an Arduino Uno just to get the software and hardware working right. Then move to a smaller form-factor Arduino like the mini or Sparkfun's pro-mini.

A servo shield might also be a decent investment. It wouldn't do anything you couldn't do yourself with wire and a soldering iron, but it will save you a lot of wiring time.

An Arduino alone (unless it's a Mega) won't be able to control the signals for that many servos. You'll need a helper chip; the TLC5940 would work well as it can handle the signals for 16 servos. (Note: they use a breakout board but the bare chip also comes in a DIP format for ~$3.)

thanks! I had not seen that nifty little board. I think this will get me started. now off to spend money and wait for fedex