GKN

GKN

GKN

GKN

GKN

GKN

The engineering company GKN might not be instantly recognizable, but it has been a leader in the world of four- and all-wheel drive for decades. In recent years, it has been working as much with electric motors as mechanical systems, and it has just revealed its latest work, which it calls All Twinster. It's an all-wheel drive system designed for plug-in hybrid electric vehicles, and GKN says it's the first such system to be capable of all-wheel torque-vectoring.

To create the GKN Technology Demonstrator 18, the company started with a Mercedes-AMG GLA, then ditched the front power-transfer unit, prop shaft, and rear axle. Up front, the GLA kept its gearbox, but it now uses GKN's Twinster torque-vectoring system in place of the existing final drive and differential.

This uses an electronically controlled clutch for each wheel that can apportion the amount of torque it receives from the SUV's 375hp (280kW) internal combustion engine. (GKN's mechanical twin-clutch torque-vectoring systems can already be found in cars like the Ford Focus RS.)

At the rear, instead of the GLA's usual mechanical setup, there's now an eAxle, a twin-speed unit called the eTwinsterX. It uses a compact coaxial motor-generator unit that provides 161hp (120kW) and 155ft-lbs (210Nm). As with the front (mechanical) axle, the unit is also able to vary the torque split between left and right wheels.

Both systems are linked and controlled centrally, allowing the GTD18 to adjust each wheel's torque on the fly to suit available traction conditions. That includes being able to over-speed an outside wheel when cornering to increase the vehicle's yaw rate, which means it will take a tighter line through the turn. The hybrid powertrain is also able to run as a pure EV with just the rear wheels driving.

Because the rear eAxle is so compact, GKN says that it should be much simpler for OEMs to add it as a "bolt-in" hybrid system to existing vehicles. However, it has only just begun testing the GTD18 at its testing facility above the Arctic Circle in Sweden, so it might be a year or two before we start to see its technology appear in the showroom.

Listing image by GKN