The Electric Motor-Accelerated Cart System was a motorized shopping cart project created by Computer Science House and showcased in prototype form at ImagineRIT 2010. As much as I'd love to claim credit for coming up with the project (or the acronym), my involvement was limited to the PC-based remote control software; the cart construction and motor control system were executed by CSH members Sean McGary and Alex Crawford, respectively.

The cart itself was an oversized all-metal shopping cart with a rear axle and two 36V 500W motors welded onto it, fitted with rubber tires and chain drive. It was powered by six 12V lead-acid batteries, and could run for about an hour on a full charge. Tight turns, braking, and reversing were unfortunately impossible due to the cheap electronics used in the prototype.


(click to enlarge)

My remote control software is simply a pair of Ruby scripts intended to be used on two wireless-enabled laptops: One in the cart, attached to the motor controller, and one in the hands of the operator. RIT's ubiquitous wireless coverage means that remote control is possible almost anywhere on campus. The "operator" script uses Gosu to capture keyboard input and display some basic feedback.

The observant will notice a webcam mounted on the handlebar in the photos. This was intended to send a video feed to the operator, allowing for long-range control, but we were unable to get enough bandwidth out of RIT's wireless during ImagineRIT to make it work. The USB-powered Woot Lights, however, were perfectly functional.

After ImagineRIT we discovered that E.M.A.C.S. had numerous structural issues that could only be fixed by a complete rebuild, so the cart was unceremoniously chopped in half and scrapped. It's unclear whether the project will be resurrected.