Vehicle would reconfigure itself based on the number of passengers

General Motors is investigating how to make future autonomous vehicles more aerodynamic, especially when there's no-one or very few people on-board.

GM Inside News has uncovered a patent filing for "Method and Systems for Reconfiguring a Vehicle Geometry".

In short, the filing details how vehicles, most likely autonomous, could reconfigure themselves to handle various use cases.

For example, if the self-driving car is heading off to pick up passengers, but has nobody inside, it could fold and store its solid roof inside, and slide a canvas roof over the top. The lower roof height would benefit aerodynamics, and improve driving range.

The car could also take on a more rectangular shape if it's carrying a lot of passengers, and morph to become rounder and slipperier if there's only one or two people on board.

Another part of the filing details how the car could, effectively, suck in its sides in order to fit into narrow spaces. It would also allow more of these cars to be packed into a parking garage or charging zone.

Naturally, the range and efficiency increases gained by changing shape like this will need to be substantial in order to justify the mechanisms and extra body parts required.

Should any of these designs see the light of day, they'll take active aerodynamics technology to another level.

Currently on some high performance cars you'll find rear spoilers that raise and lower themselves depending on the car's speed, thereby causing as little drag as possible when puttering around town, and generating extra downforce at high speeds.

More common are active grille shutters, which open when the engine needs to be breathe in more air, and close at other times to reduce drag or accelerate the warming up process.