Any fan of Formula One racing will tell you that very small changes to the underside of an automobile can deliver major changes to the speed, handling and road-holding of said automobile. Due to the extreme costs associated with wind-tunnel development, varying the shape of racing cars is largely banned, and hence very few road-going cars have seen variable aerodynamics beyond the raising of rear spoilers for added down-force at speed, as used in the Bugatti Veyron and a small number of other very expensive exotic sports cars. One of Honda's latest batch of concept cars looks set to break with tradition though, by exploring this theme with front and rear bumpers which raise and lower to offer better aerodynamics depending on the speed.

Honda's line-up of concept automobiles, motorcycles, power and mobility products at the Tokyo Motor Show this year is very impressive, and the most interesting is the AC-X, a next-generation plug-in hybrid vehicle that at first glance appears to be relatively conservative for a vehicle designed to gauge public opinion on new technologies and designs.

Indeed, the entire release devoted to the AC-X in the lead up to its debut at the 43rd International Tokyo Motor Show next month reads as follows: "A next-generation plug-in hybrid vehicle which offers a more comfortable and enjoyable time in the vehicle during all driving situations, from urban to long-distance driving. With the choices of an "engine drive mode" for more aggressive driving or an "automatic drive mode" for more relaxed driving, the vehicle broadens the joy of mobility."

That's really not a lot to go on, but an examination of the photographs released by the Japanese manufacturer reveals some interesting technologies at work, and some of them might not be all that far from production models.

Among the captions showing the car from close-up front and rear angles was the "AC-X Adjustable Aerodynamics Bumper (front)" and "AC-X Adjustable Aerodynamics Bumper (rear)".

Closer examination of those images indicates the front apron and rear bumper/pan raise and lower to obtain aerodynamic advantage - no details have been provided, so Honda's press conference on the November 30 press day at Tokyo Big Sight should be well worth attending.

Honda must have upgraded its wind-tunnel facilities in recent times, because looking at the company's concept cars set for release at Tokyo, there's clearly a lot more emphasis on aerodynamic efficiency. Even the wheel covers on the AC-X appear to close at speed to ensure every last percentage point of aerodynamic loss is reduced, and the Micro Commuter Concept is also clearly brimming with minor aerodynamic detail intended to make the car as efficient as possible.

The same set of images released by Honda also indicates that the AC-X will also make use of what appears to be a very smart "key" which will be known as Honda Smart Connect. The functionality of the Honda Smart Connect has not yet been released, but clearly the dockable handheld device is carried by the owner of the vehicle and acts as a remote connection to the vehicle to indicate the state of charge of the next-generation plug-in hybrid, hence the "Smart Connect" name.

Further functionality will need to be pretty special, because the Smart Connect is the size of a smartphone, and if that's all that can be done with the key, Honda would be better off building a smartphone app and saving owners the effort of carrying yet another gadget. Logically, the Smart Connect will have far greater functionality - any ideas?

Several other innovations stand out from the images Honda has released, most notably that the steering wheel has been dispensed with and in its place is a pair of joysticks.

Most interestingly, two of the images indicate that the joysticks retract when the vehicle enters what Honda is calling "automatic driving mode", indicating that the AC-X features some form of autonomous or semi-autonomous mode which does not require the driver to steer the vehicle.

Finally, examination of the images indicates that in addition to a heads-up display projected onto the windscreen, there's also a panoramic 3D view of the surroundings generated not only onto the driver's display, but across the entire dashboard, even onto the passenger side of the vehicle, with the driver having a view of the immediate surroundings, but the passenger getting an aerial view of the city.

Needless to say, we're looking forward to seeing this one.