The name Apogee comes as a followup to the previous two cars, Solstice and Equinox. It does not, however, share very many of the same design features.
Apogee represents a pretty significant departure from our previous formula for a solar powered car. It is the ninth vehicle out of the Stanford team and has quite a long list of changes and new features.
Rules changes for WSC 2009 and NASC 2010 have required that we switch to an upright seating angle for the driver and a 6 square meter solar array. This has precipitated a long list of corollary changes. In particular, we have gone back to three wheels to try and reduce the impact on our frontal area by placing the driver in the same wheel well as the third wheel and motor. Reducing the solar array size has given us the flexibility to round the corners on the front while staying within the acceptable bounding box size for the car.
We are required to have a door and an emergency off switch accessible from the outside. We’ve chosen to mount the door on a convenient gas spring. The emergency off button is in a reasonable place, rather than underneath the car. We have a real steering wheel with buttons artfully embedded and with no exposed interconnect wires.
The driver display shows more than just text and uses about the same amount of power as the previous version. Our CAN bus system is much more robust and carries far more useful information. We’ve built our own maximum power point trackers and battery protection system, both from scratch. We’ve encapsulated our own solar array and built a carbon fiber top shell – both departures from our recent past.
Apogee will race in the 2009 World Solar Challenge across Australia, and again in the 2010 North American Solar Challenge. Hopefully that won’t be across the cornfields.