New Audi brain to control up to 90 vehicle functions

AUDI has outlined how its latest electronic chassis system will not only continuously monitor and calculate the best ride and handling settings for its future models, but become the central brain for all vehicle systems to prevent collisions and even alter the vehicle’s attitude before a crash to minimise occupant injury.

The concept revolves around the further development and enhancing of Audi’s Electronic Chassis Platform (ECP) – Audi’s description of a “vehicle dynamics brain” – that will soon be able to link up to 90 systems including predictive active suspension, all-wheel steering, active roll stabilisation and braking. 

Audi said that in the future, the central processor “will handle longitudinal and lateral dynamics control, energy and powertrain management, recuperating energy during a braking event, determining the damper compression rate within milliseconds and keeping the vehicle precisely on track – all practically at the same time.”

“It will operate about 10 times as fast as current systems and be able to control up to 90 system participants, compared to about 20 in the case of the current ECP,” the brand said.

“Its precise data computation will also execute the requirements of advanced driver assistance functions.”

First introduced in the 2015 Q7, the ECP will be gradually rolled out in the Audi model range and will cover both internal-combustion engine (ICE) models and electric vehicles (EVs), but the brand would not give definitive timelines on the roll-out, saying the ECP would be here “in the near future”.

In its online Tech Talk session with Australian journalists, Audi said that to maximise safety, ride, comfort and handling, all components under the ECP umbrella have to be seamlessly integrated.

According to head of suspension systems development Carsten Jablonowski, the key is making the systems work cooperatively and prevent one system from dominating the others.

“The chassis still has to work superbly without the electronics,” he said.

“We have to ensure that the systems work together so that the driver of the SQ8, for example, will not know which systems are making the car so precise and so comfortable.”

Mr Jablonowski said the efficiency of the chassis and the development of new braking systems that integrate conventional friction braking with regenerative braking will greatly improve the efficiency of cars and lead to reduced fuel consumption or, in the case of electric vehicles, reduced energy use.

“It is the interplay of mechanical chassis parts with electronics to make the car better balanced. That fits the character of the Audi brand.”

But it is its contribution to occupant safety that Audi is pressing as being one of the most important developments for the future.

The active suspension together with the central processor of the ECP can help reduce collision impact by adjusting the car before impact. The concept has also been shown by Mercedes-Benz with its latest S Class model.

Mr Jablonowski said that upon detecting an imminent side impact at more than 25 km/h, the active suspension of the A8 will instantly raise the car body by up to 80mm, resulting in the other car hitting the A8 in an area that is structurally stronger.

“The deformation of the passenger cell and impact on the occupants, especially in the chest and abdominal area, can thus be as much as 50 per cent lower than in a side crash without suspension lifting,” Audi said in a statement.

Mr Jablonowski added that in this case, the ECP would be responsible for activating the active suspension and its integration with other chassis components like the air spring. 

While the new ECP system as a whole is still in development, certain systems including the new predictive active suspension are already available on models including the A8 and SQ8 with Audi saying it will rapidly trickle down to less luxurious models.

The system was revealed last year for the S8 and has subsequently flowed into other top-shelf models, with wide-reaching advantages including constantly adjusting ride comfort and handling. 

In his presentation, Mr Jablonowski said active suspension on the Audi SQ7 and SQ8 reduces body roll to a minimum.

“It provides the Audi full-size SUVs with amazingly high lateral dynamics capabilities resulting in an impressive driving experience for the driver,” he said.

“In fast cornering situations, due to the electronic adjustment of the stabiliser bar, body roll is reduced because the stabiliser, within milliseconds, smoothly lifts the vehicle side that is on the outside of a corner against the centrifugal forces with a moment of up to 1200 Newton metres.

“This makes higher cornering speeds possible and clearly reduces load change reactions as well. During straight-line driving, for instance on uneven road surfaces, a planetary gear system disconnects the two halves of the stabilizer, which enhances ride comfort. 

“As a central control unit, the ECP also matches information from other chassis technologies in the SQ7 and SQ8, such as the all-wheel steering system, the air suspension and the quattro sport differential.

“There is also the need for comfort, which is where the predictive active suspension (which profiles the road ahead using cameras and prepares the suspension for bumps) is used.

“There are about 100 criteria measured during testing for the ECP including body control, long-distance comfort, agility, damping and steering precision.

“Some are less important than others depending on the purpose of the car and the conditions where the car is being used.”

ECP is also being used as the conduit to Audi’s integrated brake-control system (iBRS) in the e-tron.

Audi said that the recuperation system of the car’s generator returning energy to the batteries can contribute up to 30 percent to the range of the electric SUV. 

“The iBRS includes the two electric motors as well as the hydraulically integrated braking system in this process and is the first to combine three different types of recuperation: manual overrun recuperation using paddle shifters, automatic overrun recuperation using the predictive efficiency assistant and brake recuperation with a smooth transition between electric and hydraulic deceleration,” the company said.

“The Audi e-tron recuperates up to 0.3 g exclusively via the electric motors without using the conventional brake – this is the case in more than 90 percent of all deceleration events. 

“As a result, practically all normal braking manoeuvres are energetically fed back into the battery.”

Additionally, Audi has become the first car-maker to develop an electrohydraulic actuation concept where the driver can no longer perceive the transition from electrical brake recuperation to the mechanical braking system.

“The brake pedal is not connected to the hydraulic system so the transition from the motor brake through the electric motors to the conventional brake is smooth and can no longer be felt by the driver’s foot,” the brand said.

“A hydraulic piston in the compact brake module generates additional pressure and braking force that complements the recuperation torque.

“In an automated emergency braking event, only 150 milliseconds elapse between the time deceleration is initiated and the maximum brake pressure is applied between the linings and discs. 

“Depending on the driving situation, the electro-hydraulically integrated Brake Control System decides whether the Audi e-tron will decelerate by means of the electric motors, the wheel brake or a combination of both – electrically and individually on each axle.”

Thanks to the ECP, this braking system is being applied to upcoming EVs but because of its safety benefits, is also slated to be fitted to future ICE models.