BMW M GmbH, the sports car division of the BMW car manufacturer, is starting the next chapter in its transition towards electric mobility. With the first pilot tests of the so-called test vehicle for innovative drive and chassis control systems, the interdisciplinary development team will now secure hardware and software solutions designed for future high-performance vehicles of all kinds of electricity.
The focus of the concept test is an all-wheel drive system that includes four electronic machines and integrated control of vehicle dynamics, which together should ensure a level of performance and experience not previously achieved, according to the manufacturer in the current press release .
With a completely new drive concept, BMW M GmbH wants to emphasize its development expertise and thus its ability to transfer the essence of the letter M to the world of pollution-free indoor mobility. The all-electric drive is combined with innovative control systems to redefine the combination of dynamics, agility and precision characteristic of BMW M cars in a high-performance electric sports car.
50 years of BMW M: The future begins in the anniversary year
Exactly 50 years after its establishment, BMW M GmbH is in the midst of a process of change in electronic mobility, which not only wants to preserve the performance characteristics of its models, but also to improve them with new aspects. The market launch of the all-electric performance cars BMW i4 M50 and BMW iX M60 began in the anniversary year. And next year, the BMW i7 M70, the first BMW M car based on the electric luxury sedan, will follow.
“In our anniversary, we are not only looking back, but above all forward“, says Franciscus van Meel, CEO of BMW M GmbH. “Production of the BMW XM, our first high-performance car with a V8 M hybrid, will begin before the end of the year. Along with our fans around the world, we are also looking forward to entering the LMDh division of the North American IMSA endurance racing series, where we will also compete with the Daytona eight-cylinder turbo engine in 2023 with one. a year later in the WEC race series at Le Mans will begin.“
Special drive and chassis technology in a familiar look
To put drivetrain technology and a chassis designed for the future, high-performance electric cars on the road for test and development drives, BMW M engineers developed a test car that has the right genes – both according to M dynamics. conventional as well as in the field of e-mobility. On the basis of the BMW i4 M50, an electrically powered coupe with a modified body in the classic BMW M style was created, whose large wheel arches enable the integration of special high-performance models with a rear axle.
The front of the car features a body torsion concept taken from the BMW M3/M4 series for superior torsional stability in very dynamic driving conditions. The layout of the radiator units is also based on the configuration developed for current high performance sports cars.
The basis of the revolutionary high-performance car, which is now making its debut on the road in a test car, is the M xDrive all-wheel drive system with four electric motors. The fact that all four wheels are driven by an electric motor opens up completely new possibilities for a very variable, very accurate and at the same time very fast distribution of the vehicle’s torque that matches the needs and conditions at all times. Within milliseconds, the power and torque of direct-acting electric motors can be measured so precisely that the load request expressed through the accelerator pedal can be implemented with a force that is unattainable by conventional drive systems.
“Electricity opens up whole new degrees of freedom for us”
For the driver, this means that completely new performance characteristics can be achieved even under very difficult conditions, such as in highly variable conditions or in rough road conditions. “Power transmission opens up new levels of freedom for us to reproduce the normal movements of M“, says Dirk Häcker, Head of Development at BMW M GmbH. “And we can already see that we can use this capability to the maximum, so that our high-end sports cars can continue to offer the M-typical and unparalleled combination of dynamics, agility and precision in a future without domestic production. ..”
In particular, the precision in the vehicle’s torque transmission benefits significantly from the M xDrive all-wheel drive system. The four motors are connected to a central, highly integrated control unit that constantly registers the driving conditions and the driver’s wishes. The best transfer of power to the road is calculated within milliseconds from the values of the accelerator pedal position, steering wheel angle, longitudinal and lateral acceleration, wheel speed and other parameters. The signals of this reach the four motors quickly and without distortion through a multi-plate clutch and a direct differential to the four motors, which can execute them immediately and accurately.
This type of driving dynamics and steering control was developed to practical maturity in extensive development and testing phases, first on virtual models and then on test benches. With the actual use of purpose-built hardware and software, the concept test car is now on the road. The interior of the four-door coupe is equipped with advanced measurement technology, with which every completed driving situation can be analyzed in detail. In the test laboratory on the wheels, the theoretical knowledge about the full torque distribution of the car can be compared with the reality on the road and considered for further applications.
Recuperation with four motors
This detailed work is necessary so that the high-end models of the future will be characterized by exactly what has made BMW M cars indisputable for 50 years: the linear design of the car’s power and lateral dynamics that enable manageable handling to the limit. The fact that this limit area is pushed even further by the forward-looking drive principle was already evident from the first test kilometers of the concept test car on closed roads. Thanks to the sensitive metering of the vehicle’s torque and the execution without any noticeable stability, the highest cornering speed can be achieved, for example, even on wet or snow-covered roads. In this case, the car drives without effort and without a tendency to slow down, because the torque of the car to the rear wheel outside the curve has already increased in parallel with the steering angle.
The high performance characteristic of the new drive system is also used when braking energy is recovered. All four engines can take over the operation of the generator and feed the electricity back to the high-voltage battery, up to the limit of driving dynamics, for example when braking before cornering.
Source: BMW – press release of 08/17/2022