This is the first of my blog posts on a project that I currently call “Project ZK”. In addition to being into the Internet of Things, programming, and all things tech, I also spend a lot of time off-roading in my heavily armored and modified Jeep – the “Zombie Killer”. The off-roading, rock-crawling drone that I intend to build is inspired by the zombie killer Jeep, which is why I’ve decided to call this “Project ZK”. Jeeps are often referred to by a 2-or-3-letter designation such as TJ, YJ, JK, etc. My big 4-door zombie killer is a JK, and so I’ve decided to label my little drone a “ZK”.
After experimenting with some small IoT projects, I decided to dip my toe into the deep end of the pool and get a 4WD chassis from Actobotics. I bought the kit from ServoCity, a site that should be banned purely for its addictive nature. I could spend all day on that site and never get bored.
The Actobotics chassis (and the corresponding plethora of accessories) gave me that same feeling I got when I was a kid working on the Erector sets (remember those??), only this time it’s an erector set for robots. You can get all kinds of channels, mounting accessories, bolts, and other equipment so you can add modules and things to your project without the need to start custom cutting aluminum or plastic.
Once I got it assembled and I acquired two RoboClaw 2x30A motors, I was ready to manipulate the motor controllers with my Spark Core. The only problem was I needed some serious wiring done, and I was in over my head. I didn’t know what gauge wires to use, didn’t know the best way to set up the motor controllers to be controlled as a serial bus, etc. For this, I turned to a good friend who runs the Heli Flight Center – this place is basically drone heaven.
With his expert guidance and skills, we were able to locate the two RoboClaw motors down inside the protected plastic portion of the chassis, wired them up to each other, set it up for LIPO battery supplied power, and even made some small Y cables to allow a single set of TX/RX wires coming out of the Spark Core TX/RX pins to manipulate the controllers via Packet Serial (more on the code in an upcoming post).
With this all in place, I was finally able to get enough code working to allow an internet-triggered motor self test to happen. To me, this is the drone hardware equivalent of “hello world”. Now that I know it can be told how to move, the real fun begins. Here’s a quick video showing the chassis in action during the self test: