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TRW Forecasts Electric Park Brakes on 1 in 5 European Passenger Cars by 2015

TRW Automotive Holdings Corp. is forecasting—based on vehicle manufacturer data—that Electric Park Brake (EPB) technology will be standard on one in five of all European-built vehicles by 2015. Its projections also show that approximately half of the mid- to larger-sized European passenger cars will have EPB in this timeframe, while the technology will continue to penetrate other regions.

TRW anticipates further growth for its Electric Park Brake system that enhances safety and fuel savings for passenger vehicles. Click to enlarge.

Many automakers in Europe have already fit the system—first launched by TRW in 2001—on one or more models, including: BMW’s 5 Series, 6 Series Coupe, X3, and Z4; Ford Galaxy and S-Max, Volvo S60, S80, V60, V70, XC 60, and XC70; Renault Megane and Scenic; and Volkswagen Automotive Group’s Audi Q5, A4, A5, A6, A7, A8, VW Tiguan, Sharan, Model CC, Passat and Passat Coupe.

The EPB system, utilizing electrical cables and a control switch, simplifies routing and allows for greater freedom of design for vehicle interiors. Its smaller package becomes even more attractive as vehicle manufacturers continue to requisition vehicle space for new features and options and it can significantly reduce weight when compared to conventional park brake systems.

—Josef Pickenhahn, TRW vice president, braking engineering

In addition to providing parking brake functionality, EPB is a fully integral part of the brake system with features such as dynamic actuation and brake pad wear sensing technology. It also offers enhanced quality and reliability when compared with mechanical systems. EPB also significantly enhances safety in emergency stop situations with full four-wheel anti-lock functionality versus standard park brake emergency braking, which only functions on the rear axle, TRW notes.

The EPB functions as a conventional hydraulic brake for standard service brake applications, and as an electric brake for parking and emergency braking.



Video of an electric handbrake in operation:


I'm not sure I am happy about the loss of the mechanical parking brake as a fail-safe. I have experienced on two separate occasions loss of service brakes through sudden and catastrophic fluid leaks. In both cases enough fluid was lost that there wasn't sufficient fluid for the separate circuit of the hydraulic service brakes could do much, so in both cases the use of the parking brake was necessary to stop the car. Merging the parking brake function with the hydraulics seems to lose that redundancy in my book.

I have also experienced sudden loss of electrical power at speed, which is why I scrutinize the electrification of braking systems for proper fail-safes. I did buy a Prius knowing that its service brakes were 100% electric controlled and assisted, but in that case the braking system has a capacitor to give you enough time to stop the car in the event of a loss of 12V power. And the Prius retains a cable-actuated parking brake as additional backup. I would not have been willing to buy the car had it been all-electric had it not also had both the backup power and a mechanical parking brake for redundancy.

I have to wonder how long before somebody tries to sell a car with all-electric brakes in conjunction with electric parking brake? It looks like Leaf and Volt will go that way. I will want to know what additional redundancy has been provided before I trust these systems with my life.

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