The Spin Control rocket is an invention product I developed at IDEO and was licensed to Estes Rockets. The idea was sparked by an electronic toy top that could count the number of revolutions it made – and even display this number while spinning.
We figured this would be a fun feature to add to a model rocket – it would count how many revolutions it took while in air. Estes was intrigued by the idea and wanted a fully working prototype. That’s where I came in.
This project presented a couple of particular challenges:
- Weight was a huge concern and adding a prototyped LCD screen would be too heavy to fly
- We had to provide a manufacturing ready schematic of the spin-detection circuitry
Estes had used LCD screens in previous rockets so a prototype of the actual screen was not necessary. So, to solve the first challenge, I decided to make the prototype “announce” the number of spins verbally. I’d launch the rocket, collect the nose cone and then plug it in to a black box which contained a speaker. The electronics in the nose cone would continually announce the number of revolutions the rocket completed until it was reset. Problem solved.
Next, I needed to prototype the spin detection circuitry. To start, I was able to hook up the circuitry from one of the spin detection toy tops. Borrowing from the toy top, I was able to make a fully functioning prototype to prove out the idea. However, the spin detection was not sensitive enough for the needs of a rocket. The circuitry in the toy top could detect as few as 3 spins per second, but in a rocket this caused too many missed spins. I had to modify this circuit to detect a slower spin rate.
While I do have a background in electronics, my experience is mainly in digital electronics – this circuit is analog. I found schematics for the circuit online and I spent time trying to modify the circuit by adjusting the capacitors and coils. I wasn’t having any luck, this circuitry required expertise beyond my capabilities. Luckily, we had a resident electrical engineer from a different department who saved the day He was able to show me exactly what I needed to do to make the circuit more sensitive and with this knowledge I was able to design a circuit which could detect revolutions of just under 1 spin per second. This was plenty!
This project earned me the nickname of “Rocket Girl” at IDEO!