Mustang Parts
   Carrying Saleen wheels and Bullitt wheels.

Thursday, April 29, 2010

Aptera Flounders On Lane Change

This is bad news.  If the Aptera, a supposedly well developed and carefully engineered vehicle, can't negotiate a Consumers Union lane change at a measly 45mph, they are in big trouble.  It probably has a lot to do with the tricycle design -- the rear end is likely to want to come around without strong ESC intervention because it has so much less grip than the front.  From CU's blog:

Watched by a large group, including many note-taking and video-taping team members, the three-wheeled Aptera car struggled to find a clean run. More than two dozen attempts were made, with the car routinely sliding enough to topple several cones. In watching, it seemed natural to question how difficult this test is to pass. However, all current production vehicles, from small cars to large trucks, can successfully negotiate this test. We expect the Auto X Prize finalists to do the same.

For reference, just about any mass produced four wheel car can easily negotiate a lane change maneuver at 45mph.

1 comment:

Mike Smitka said...

This problem ought to be amenable to ESC, as you note. The Bombardier (BRP) Can-Am Spyder "trike" is a viable road vehicle which had to overcome similar stability issues. In their case, Bosch Engineering Group worked with BRP to chose appropriate off-the-shelf sensors (eg, wheel speed, yaw, steering rotation) and then develop the control algorithms, which turned out to be rather different than those needed for 4-wheel vehicles. Bosch and BRP were an Automotive News PACE supplier of the year collaboration awardee for this. [See for a description.]