Description: This UAV is intended mostly as an education platform to teach you the basics of microprocessors, embedded system programming and autopilot design. It will fly, but it's not designed to be a real production UAV. That said, it demonstrates the advantages of creating your own microprocessor-based autopilot: maximum flexibility and expandability by fully integrating the autopilot and the R/C control system.
Hardware level integration means that the onboard computer can control as many or as few aircraft and camera functions as we want. The downside is that the particular embedded processor we chose, the BASIC Stamp (which is the easiest to program), is also very limited in processing power and memory. But the same concept, extended to more powerful processors such as the Parallax Propeller or a Linux-based Gumstix, could be quite capable indeed, potentially allowing the autopilot to handle both navigation and stabilization functions, rather than using an off-the-shelf commercial unit for stabilization as we do in this UAV. Or, if you want something like Basic Stamp but more appropriate for a production UAV, follow along as we develop ArduPilot, the open source Arduino-based autopilot, here on this site
Features: Unlimited pre-set GPS waypoints, with programmable options such as circle and hold. GPS-controlled altitude hold. With Pentax A30 setup, autopilot can control camera to take pictures at waypoints or at a set interval along paths.
- Airframe: NSP Viking ($130. You'll need another $300 worth of batteries, a motor, and radio equipment in you don't already have them)
- Autopilot: Custom circuit board based on a Parallax Basic Stamp module, an EM406 GPS module and a FT639 Servo Controller chip all on a Parallax development board (someday we'll move that to a proper soldered circuit board). (around $200 all told). Note: if you don't mind the extra size, Parallax also has a very good servo controller board that will also work. There is code for each at the link below. A step-by-step tutorial on setting this hardware up can be found here.
- The software code is now in beta. You can read about it and download the files in this post.
- Stabilization: FMA Direct FS8 Co-Pilot (infrared sensors, $115)
- Imaging: Pentax Optio A30, which is the smallest high-res camera I've found that allows for IR shutter trigger, plus a Prism R/C-controlled IR trigger. (both are around $200). This is also good candidate for the IR stabilized camera mount described here, which doesn't require the Prism trigger.
- Target cost: between $700 and $900 depending on how much of the required stuff--such as a suitable camera--you've already got laying around.)
Comments
You can buy three Ardupilots for the price of the Parallax BS2p that Chris used in this project and the total size of the board is much bigger and bulkier than the Ardupilot. Also, you have to throw in a serial to servo controller which costs at least $40. I have used both the Parallax BS2p/BS2p40 and the Propeller in robotic projects and the Ardupilot is by far the best for beginning UAV projects.
Just a thought.
Regards,
TCIII
happy holidays and good luck.
I am wanting to build my own autopilot during my holidays from April to June .
I have bought all the ardu components and was going to assemble them , but thought why not make a basic one myself , came across this and thought it might be a good beginning.
venkat