With the development of autonomous driving, the vehicle system architecture is about to be re-written. Today, the driver does the integration of propulsion, braking and steering. To reach full autonomy, the subsystems need to control accurately and communicate back, for the system to be able to analyze the data and make correct decisions. System integration is thus the key for autonomous driving to become successful, according to Haldex.
"System integration requires open communication. Today, only selected data of the wheel end performance is shared in the system, even though most of a vehicle's behavior is determined by the wheel end performance. Haldex wants to change that. We fully believe in open systems where the OEM gets full access to the data from the wheel end," says Andreas Jähnke, SVP R&D at Haldex. "By developing the brake systems jointly with OEMs, we re-shape the principles for the vehicle system architecture. We know that new and old technology will live side by side for many years. By separating the software from the hardware, you can use the same software functionality to execute different mechanical tasks, hence you can have a vehicle structure which can run both pneumatic and electromechanical brakes. We also want to move away from the principle of the EBS being a black box that is the central hub for the intelligence in the brake system. To build a scalable system with maximum control and predictability, more technology and intelligence should be placed at the wheel end."
One of the new products from Haldex that is based on this concept is the Fast Acting Brake Valve (FABV). It's a high-performance valve, placed at the wheel end together with an ECU, that acts ten times as fast as conventional modular based systems. The result is 15 percent less stopping distance, but also the ability to control the lateral and longitudinal friction levels on each wheel.
"When replacing the driver, you need redundancy on different levels," Jähnke said. "We are not unique to provide steering by braking, but our wheel end accuracy with the FABV is unique."
Another product in development that also provides 15 percent improvement of the stopping distance, compared to air disc brakes, is the Electromechanical disc brake from Haldex. It's currently being tested on electric buses.The benefit of the electromechanical brake is not only its improved performance compared to today's air disc brakes, but the energy gains you get when you can replace the pneumatic brake system with a full electrical brake system.
Today's electrical heavy vehicles still has a pneumatic brake system installed. It needs about 2.5 times more energy than an electrical brake system. It's requires a compressor and other brake system parts you can remove from an electronic brake system.
"With our patent on electromechanical disc brakes and on-going vehicle tests, we are confident that we are a world leader on electromechanical brakes for heavy vehicles," Åke Bengtsson, Haldex CEO said.
In Hannover, Haldex showcased a cross-section of products. The new generation of the spring brake actuator LifeSeal+ premiered at IAA. Haldex has developed the brand-new double diaphragm spring brake actuator LifeSeal+ for air disc brakes, which is primarily intended for use in semi-trailers in long-haul transport throughout Europe. Haldex presented the LifeSeal+ actuator at IAA together with air disc brakes from the ModulT range.
