I decided to see how far I could go with a Pi Zero and a pi camera. Of course this means I can only put 1 camera on the Pi, but I gain flexibility in that the cameras are no longer USB cable length limited.
I also decided to I to try making the camera steerable using this little adafruit gadget.
Here is the final BOM:
- Raspberry Pi Zero with basic case and kit of leads
- Raspberry Pi Camera (mk 2)
- Raspberry Pi 2 Camera cable
- Adafruit mini pan tilt kit
- a few bits of wire
- 220uF & 100nF capacitors
- High power usb wart
- oh yes and a wifi or lan dongle
You will also need a usb hub for initial setup at least (I run mine with just the wifi dongle, so I don't need a hub)
The parts of this I was concerned about were:
- Were the servos and the pan tilt kit going to be stable / accurate enough?
- Would a single core processor cause glitching or other problems?
- Could I drive the servos from the Pi's 5v supply? (they draw about 250mA running, 600mA stalled and 10mA idling.)
- Was there a reasonable way to route the ribbon cable?
- just about
- No, all looking good (using pigpio to drive the motors)
- Yes, adding the capacitors improved stability (of the motors - the Pi was fine)
- meh - ribbon cables are always a pain with 2 axis movement.
- is it safe to run the 5v servo supply from pin 2?