Oh right, I’m a programmer – here’s an engine test

Years ago when dinosaurs roamed the Earth and computer monitors weighed more than golden retrievers I went to college and got a very nice degree that has nothing to do with how I’ve supported myself for the last two decades. I decided to diverge from the whole Professional Writing thing and pick up HTML and JavaScript just in case the Internet took off. It provided the basis for a career that started with PHP web application development where I figured out two things:

  1. Most engineers suck at user interface
  2. I enjoy focusing on front-end development

While the second point does speak to a special kind of masochism, I channeled it into a career, learning CSS, SCSS, a veritable cornucopia of JavaScript libraries and frameworks, cross-platform website/web application development, and email creation for both modern software and Microsoft products. (Yeah, I went there. Shame, Outlook. Shame.)

Although I love programming I have learned that there can be too much of a good thing. Years ago I decided to do web development professionally but keep it largely isolated from what I do in my free time. I took an introductory course in Arduino back when working in Philadelphia and have been hooked ever since, hacking away in one form or another with increasingly complex projects. There’s something insanely fun about envisioning a physical project, solving the design and technical hurdles to make it happen, ingesting new skills and techniques, and solving problems there are no clear answers to. As a front end developer, everything I do comes down to the placement and manipulation of rectangles. While you can accomplish some pretty amazing things with those rectangles and the content within them, programming custom hardware opens up even more interesting possibilities.

Thruster with electronics box

The most recent one, and the project I plan on documenting on this site, is the fake rocket engine I strap to the back of my bike. The video above is a preliminary test before I had integrated the purple control box seen below.

I’m a regular on the Thursday Night Cruise here in Boulder, where people dress up, adorn their bikes with lights and decorations, and roam the streets and paths in big rolling party.

I’ve been contributing my own wee shenanigans as I’ve gotten more involved over my past few years in town, especially after getting a 3D Printer (Flashforge Creator Pro) last year, and this is the most recent outcome of my tinkering. I was recently invited to bring the rocket setup down to Pueblo, CO for their first Maker Faire where I got some great feedback on my project and enough people asked for details that I realized I should probably put together some sort of online description beyond the one I provided for the Faire.

Side view with electronics box closed

The entire contraption has evolved over time, but the original pieces are still in place. The body is a juice container on its side with an almond container stuck on front of it. An RGB (multicolor) light strip is glued to the inside of the almond container where it shows through the plastic, the rest of which is covered in reflective metal repair tape. A combination of components printed using silver PLA and translucent NinjaFlex help diffuse the lights on the exterior. The lights are used to emulate a spinning effect with Arduino-driven logic. The back ‘thruster’ contains a small ring of similarly multicolored lights that are used for a flickering effect, wrapped in plastic to make them waterproof enough to survive the condensation of freezing solid.

Exhaust port with LEDs

Inside the intermix container is a small amount of dry ice. A fan pulls air in from the front of the assembly (almond container), through the dry ice, and out the back passing through the light ring. A small pump, also controlled by the processor, sprays pre-heated water drawn from an insulated container onto the dry ice. The heat introduced causes the dry ice to evaporate, emulating smoke. A small heating pad mounted on the bottom provides enough warmth to prevent the water from freezing solid after passing over the dry ice, allowing it to drain into a small gravity-container attached to the rear of the engine.

Electronics box internals

The entire thing is driven by an Arduino Mega and while the documentation leaves much to be desired I’ve shared the code driving this whole thing on github:

Stay tuned, I’ll be compiling a more detailed page about Tiffany the Wonder Bike and her faux turbine engine in the near future! There is also a whole slew of updated behaviors I need to document, including numerous light modes with sound reactivity on the front of the control box.

Front-mounted control box