Looking for some help really about how to interact with the GPIO that the Raspberry Pi has.
Looking to make a controlable Helicopter with a raspberry pi at it's sorce. Problem is that I have very little experiance with Electronics and zero in programming. However I am good at flying helicopters
Where would the best way to start using reading about GPIO ? Programming will slowing come about more i practice and learn it. However no idea if I would need additional board for the servos.
ultimate goal is to make a Quad-copter (they are generally more forgiving) with R-Pi in the middle being controled by a laptop in FPV
You may wish to start by looking at the arduCopter and arduCopterMega projects..
6 months or so ago, I looked at this with a lot of interest, however the project I was working on never got off the ground (as it were!) but I did learn a lot about quad/hex/etc copters and their control and so on.
So while the RPi is more than capable of doing the calculations involved, (a 16MHz, 8-bit micro can do them in software) I fear it's lacking in the IO required to do the control. So, 1 PWM output per motor for a start – so 4, one for each motor. Then there's the sensors – to do it properly requires 10 sensors – barometric pressure, then a 3D compass, 3D gyro and 3D accellerometer. Some of these have analogue inputs and some use a digital bus. The arduCopter "solved" some of this by having an IMU shield – that talked back to the host via the SPI bus, so if the SPI is working on the RPi, then it may be possible to just use the arduCopter IMU shield directly… (still lacking in PWM outputs though)
However.. You will not successfully control anything in real-time with the supplied multi-user, multi-tasking Linux kernel. Imagine you're hovering and the control loop tweaks the speed of one rotor to compensate for a bit of drift (as it needs to do constantly as these things are inherently unstable) and then something else decides to run on the RPi – a cron job, some data comms, logging, etc. and the control process gets stalled for 0.1 seconds – it will flip over in that time. You really do need absolute control over the hardware driving the controlls with precise timing otherwise it will be as unstable as a6 month old baby taking their first steps... (and you'll be taking it home in a bin-liner)
Far better might be to use it as a telemetry controller/ground station – however everyone else is currently using a laptop for that as they come with built-in screens and keyboards.