Hey Guys! (meant in the most gender neutral of ways),
I have taken my first real step toward building a DIY UAV! This will be boring to most of you, but to someone as far behind the curve as I am, this is HUGE. This community has come so far, and in such a relatively short period of time, that autopilots for RC planes are almost plug-and-play. However, I am determined to learn the basics of process control before moving on to an autopilot. After all, that's where you had to be a little over a year ago to even consider a DIY Drone.
I didn't start out with a LEGO Mindstorms, like this site's founder did, but I did get a Parallax BASIC Stamp Discovery Kit, which I believe was his next step. I don't plan to attempt to make an autopilot out of this controller--it's just for learning.
Now, I want you to pretend that the green LED to the right of the resistor (that's a 470 ohm resister, by the way) in the above photo is blinking once per second. I did that! Yes I did.
I'l like to say "stay tuned," but my projects tend to span years it seems. Maybe I can speed things up this time.
Paul
Comments
Gotta go. Time for Lesson No. 2!
Paul
-John
- a good solid processor that easily deals with floating point operations and integers larger than 8 bit.
- a good solid C-language development system (a person could always argue the finer points of integrated development suites but the arduino tools are more than functional.)
- fail-safe muxing circuit integrated right on board. (THIS IS IMPORTANT!!!)
- ability to read the signals from 4 (and possibly more) channels off your receiver
- ability to drive 4 servo outputs
- several analog inputs and several digital inputs.
Perhaps this point gets lost because the ardupilot comes with default firmware already written and most of the discussion here assumes you will run that firmware, but at it's basic level, the ardupilot is just an ATmega328 CPU with all the into's and goes-out-of's wired to 0.1" header pins. Even though the default firmware has all the pins allocated and purposed and programmed, there's nothing etched in stone there. You can rewrite the firmware from scratch to make any of those pins do anything you want.
So just like you can take a pic processor and allocated the pins to do whatever you want and flash the led's on and off, you can do all those exact same things with the ardupilot board. The only thing UAS specific that it gives you is it's built in fail-safe mux (which in my opinion makes it even more desirable as a starting point.) For safety purposes, a manual override is an !ABSOLUTE MUST! so if you pick a different board and a different processor, you'll have to go out and purchase or develop a manual override circuit yourself and add that on top of whatever other board you are working with.
I don't want to sound negative about the Pic though ... engineers know that there are always several good ways to solve the same problem, so if you understand a particular platform and know how to make it do your bidding that might be the best path for you to take. A successful project starts with a solid platform that has the features and capabilities you need, but then requires solid engineering (both hardware and software) to push it forward through the development process and finally across the finish line as a solid robust working system.
Congrats on starting your journey! I learned a lot with the Basic Stamp, and it was a great introduction to embedded programming. But just one warning that the reason I abandoned it was that it doesn't support floating point and that makes an autopilot REALLY hard.
So do use the Basic Stamp to read PWM and other sensors and drive servos, etc, but when you want to do more, I recommend you switch to Arduino. It's almost as easy to use as the BASIC Stamp, but much more powerful. This is a great starter kit.
That would be great. I'll send my e-mail address in a PM.
Paul