Electric Pink Bunny Slippers

Greg Solberg, Firmware Engineer, May 17, 2007

A Senior Director of Engineering at work never specifically said that she would cause me bodily harm if I did not write a blog entry about my bunny slippers. So I wrote, “They are size 7-½ fluffy pinks with big ears and little, white puffy tails, and I really like them.” She said that I should consider elaborating. She also never specifically pulled out an instrument of destruction.


Yes, those are electric bunny slippers

There are a lot of automotive enthusiasts working here at Tesla Motors. I, particularly, am an alternative vehicle enthusiast with an emphasis on “alternative.” In 1995 my friend Kenny and I decided it would be a good idea to cruise around the Black Rock desert, the site of the annual Burning Man festival, on an electric mobile couch. I was just getting acquainted with electric vehicles at the time, and the couch provided a perfect test bed for a 36-volt DC motor controller I was working on.

The couch inspired some of my friends and me to build a series of mobile furniture pieces: floor lamp, end table, love seat, and Barcalounger, to name a few. Then my significant other Lisa suggested that perhaps we should work together on a project and combine our skills. This was a good idea for several reasons, not the least of which was that it meant I could avoid playing Scrabble with her and still get points.

Lisa came up with the idea to design and build a pair of giant motorized bunny slippers that we could drive separately but equally. She is one of the only people I know who can think up an idea like mobile pink bunny slippers and have the vision and artistic talent to make it succeed brilliantly. She made me say that, but really it’s what is under the fluff that makes them special. She made me say that too, so that she doesn’t sound conceited.


Greg and friends take the couch for a spin

So back to my bunny slippers. They are 7.5-feet long and can scoot along at a top speed of about 15 mph. Both feet (yes, there is a left and a right) are covered with plush pink Flokati rugs the exact color of cotton candy. We purchased the Flokatis online from “Hollywood Love Rugs.” Our contact guy was Vinnie. He gave us a deal. Guys named Vinnie are like that. (Note: Flokatis aren’t machine washable, despite what guys named Vinnie tell you. Lisa spent hours finger-combing mats out of pink fluff.) However, the really important information is this:

They are, of course, electric battery powered slippers. They each have a 36-volt system using six YellowTop 12-volt Optimas. Anyone who has used these 38 pound, 50 Amp-Hour, deep-cycle, sealed, yellow lead blocks will know that this is way more battery than one needs for a bedroom slipper. The batteries served their first life in my converted electric Honda Del Sol. The two front wheels are chain driven by a 7-inch brushed DC motor made by Advanced DC Motors. This kind of motive power is also way more than any fluffy footware really needs. The motors were surplus from the failed Tropica electric car venture by Renaissance Cars and are much happier working in the big toe of a giant slipper.


A view 'under the fluff'

The frame is welded steel and plywood. I taught myself how to TIG weld on the soles of these shoes. “How hard can it be?” I said to myself. The lucky driver sits on a pillowed tractor seat and steers by the rear third caster wheel in the back. There’s a reason you don’t see too many rear caster steered vehicles. It has something to do with stability and cornering at speed, but I wasn’t listening to my friend Bob, who knows about these things. It was much more important to listen to my chief creative officer and get the visuals right. I understand forklifts are one of the few vehicles with rear wheel steering. If this Tesla Motors electric car thing doesn’t work out, I may apply for a job as a forklift driver.

You might be wondering what pink bunny slippers have to do with Tesla Motors. Tesla Motors has set out to change people's perceptions of electric vehicles as slow and ugly. Well, my slippers are faster than most, and not so ugly, I hope. I’d like to go on some more about how the Tesla Roadster will change the world, but a Senior Director of Engineering is now telling me that I need to write a blog about my electric muffins.

Editor's note: You might be able to spot Greg and his electric muffin tootling around the Maker Faire in San Mateo, Calif., this weekend, May 19-20. The faire, which showcases arts, crafts, and science projects, will be held at the San Mateo Fairgrounds.