GM's EV1

The current background for this post is a picture of the remains of General Motors EV1. Crushed and stacked for recycling or whatever.

I was lucky enough to work on the EV1 from 1990 to 1996, because of my gear experience. I was hired by Delco Remy, to work on the gearbox part of the drive unit they where making. Delco Remy had expertise with electric motor design and manufacture but little experience with gears other than starter pinions and distributor dives.

At the time I joined the team they were working on the original Impact design which Aerovironment had done. This design consisted of a separate motor and gearbox to drive each front wheel.

One small issue with this system was to match the torque of the drive units to minimize "torque steer". Imagine also what might happen if one of the drive units had a problem when driving at speed, instant change of direction.

We began working on a single motor system with a reduction gearbox and differential  to eleminate the steering problem. Of course the main driver for the design was that it had to fit in the car as it was already far down the development road.

We made some crude prototypes and proved the idea was viable, and after working with Allison Transmission a production version of the single motor concept was developed.

For the single motor design I was the Product and Manufacturing Engineer responsible for the rotor shaft, gears, differential, and oil pump.

One of the fun aspects of working on the Impact was getting to be a part of the team that took a proof of concept vehicle and set the electric vehicle speed record in 1994, but that's another story.