Wednesday, January 30, 2013

Wooden Electronics Prototype

After working on the suspension for the last couple of months during IAP we decided to get the system working with our 72V batteries.

We put together all the power electronics on a big 3/4 inch piece of plywood and wired one of our Geoby bikes to it.

The electrical system has a 12 V system powered by the Vicor DC/DC converter, this system powers the contactors. It also has a pre-charge switch and a killswitch that closes the contactors from the handlebars. The wooden prototype was nice because it allowed us to see the different parts of the electrical system clearly. We also got really good practice at de-bugging LED error codes from the Kelly Controller as well as playing the hall effect sensor game numerous times!

We used a big plastic container filled with three 80lb sandbags to simulate the future battery weight. 

Here is us working on the prototype:

We were very excited when we got the motor spinning (finally!)
Notice the big black container (where we stored the cement bags.
After it was "done" we took it out into the hallway for a classic EVT tradition, the maiden crawl in the N52 hall! While doing this we found out we needed to rethink our wiring strategy and add many quick disconnects to the system to make it much easier to assemble. Rango and I ordered some fancy MOLEX automotive connectors and made the wiring much more reliable.

Making sure everything was wired up correctly!
After ample testing indoors it was time to battle the Boston winter and take eBike out for a spin in the road.

Nick suffering in the cold!
No electrical system yet, we were getting used to the suspension and the weight.

Here is a video of Rango out in the cold on the eBike!

IAP 2013 was extremely productive in getting things rolling (literally!). Our next step is to continue testing and hopefully go out and do some long range testing outside the city!