I'm a programmer by trade, and an amateur aerospace nut, with some degree-level training in both fields. I'm working on a UAV project, and while the good people over at DIY Drones have been very helpful, this question is a little less drone-related and a little more general robotics/electronics. Essentially, I'm looking at options for ground stations, and my current rough plan is something like this:
I have a PC joystick with a broken sensor in the base, which I plan to dismantle, separate the handle from the base, insert an Arduino Nano into the (mostly hollow) handle and hook it up to all the buttons and the hat thumbstick. Then, where the hole is that used to accept the stem to the base, I fit a bracket that runs horizontally to hold a smallish touchscreen (think Razer's Project Fiona tablet with only one stick), behind which is mounted a Raspberry Pi. The Nano talks to the RPi over USB as a HID input. The RPi will be running some custom software to display telemetry and other data sent down from the UAV.
My main question whether that Nano would have enough power to run the XBee that provides the telemetry link without causing lag in the control inputs. It's worth mentioning that the UAV will be doing fly-by-wire moderation, so slight stutters won't result in wobbly flying, but serious interruptions will still be problematic - and annoying. It's also worth mentioning that this will only be used as a simplified "guiding hand" control; there will ALWAYS be a regular remote control available (not least because of EU flight regulations) so this is just for when I don't want to use that. If that Nano won't do, what are my options? My first thought is to get a second Nano and get that to drive the XBee (the RPi has two USB ports after all) but there may well be a better way.