BMW Commences Trials For Its New Revolutionary Four-Wheel Drive System

Starting a new chapter in its transformation towards electric mobility, BMW has commenced the first test drives of a prototype for innovative drive and chassis control systems.

Via a concept test vehicle, the first trials were put to test the hardware and software solutions designed for future purely electric high-performance cars.

The testing focuses on a four-wheel drive system comprising four electric motors and an integrated driving dynamics control system that together deliver an unprecedented level of performance.

In order to bring this new ideology onto the road for test and tuning drives, BMW as mentioned have developed a concept test vehicle that carries the appropriate genes.

Based on the BMW i4 M50, a purely electrically powered coupe has been created with a modified body in the typical BMW M GmbH style. 

Of which, underpins wide wheel arches that permit the integration of specifically manufactured high-performance front and rear axle designs.

Then, the front end of the vehicle features an adapted body strut concept taken from the BMW M3 and M4 series for particularly high torsional rigidity in extremely dynamic driving situations. 

Its arrangement of the radiator units is also based on the configuration developed for the current high-performance sports cars.

Now comes the core of it all, the drive system. Being tested inside its chassis is an electric M xDrive four-wheel drive system with four electric motors.

Outstandingly, all four wheels are each driven by an electric motor offering new prospects for infinitely variable, extremely precise, and at the same time very fast distribution of drive torque. 

Within milliseconds, the e-motors’ instant power and torque reacts so precisely that the load demand via the accelerator pedal can be realised at a level unfeasible by conventional drive systems.

Meaning the driver is able to experience entirely new performance characteristics even under extremely demanding conditions such as in highly dynamic situations or adverse road conditions. 

To deliver the instant torque, the four motors are connected to a central, highly integrated control unit that permanently monitors the driving condition.

Through it, the ideal power spread is calculated from the values for the accelerator pedal position, steering angle, longitudinal and lateral acceleration, wheel speeds and other parameters. 

Also, the signals for this are transmitted just as quickly and directly via a multi-plate clutch and differentials to the four motors, which are able to implement them immediately and precisely.

Just like other BMW M models, the new drive system further pushes the limits of the handling dynamics that are already known to be performing remarkably.

During the first test kilometres on closed off-roads, the concept test vehicle proves this to be true as it achieved significantly higher cornering speeds, even on rain-soaked or snow-covered roads.

Notably, the vehicle steers effortlessly and without a tendency to understeer, as the drive torque for the outside rear wheel has been increased parallel to the steering angle.

Other than that, the high-performance character of the new drive system is also evident in the recuperation of braking energy. 

Namely, right up to the limits of driving dynamics, the four motors can assume the function of a generator when braking before a bend, and feed electricity back into the high-voltage battery.

Elsewhere, for a realistic application of the hardware and software, the test vehicle’s interior is armed with a plethora of measuring tech that can be used to analyse in detail every driving state. 

As such, the theoretical results for the perfect distribution of drive torque can be compared in the rolling test laboratory with reality on the road, and taken into account for further programming.

That said, with the entirely new drive concept, BMW is underscoring its development expertise and also its ability to transfer the essence of the letter M into the world of locally emission-free mobility.