Delphi Supports Renault With Brake-By-Wire Technology For New Environmental Concept Vehicle

PARIS, Sept. 19 -- Renault has selected Delphi as its partner to implement an advanced brake-by-wire system on the Ellypse concept car, shown at the 2002 Mondial de l'Automobile (Paris Auto Show). The Ellypse is designed to illustrate Renault's commitment to sustainable development by delivering high levels of comfort and performance within an environmentally friendly design.

Delphi's Electro Mechanical Braking system (EMB) makes a substantial contribution to this goal by replacing the conventional hydraulic braking system with electrically driven actuators. This eliminates the hydraulic fluid, which is difficult to extract and recycle at the end of vehicle life, simplifies manufacture and eliminates the need for periodic fluid changes.

"We have a very close relationship with Renault and are delighted to be working with them on this environmental vehicle. It is a subject about which both companies are passionate," says Jean Botti, chief technologist of the Innovation Centre for Delphi's Dynamics & Propulsion Sector. "Delphi aims to help its customers take vehicles out of the environmental equation. The Ellypse shows how a substantial step forward could be achieved."

Each EMB calliper integrates a DC (direct current) motor, a gear reduction stage and a ball screw into a package that is only a little larger than a conventional calliper. A central processor provides control and a pedal feel emulator provides driver feedback. An integrated electric parking brake operates on the rear wheels. The units can be supplied as "plug-and-play" modules ready to bolt onto the vehicle.

Other benefits of Delphi's Electro Mechanical Braking system include near elimination of the residual torque between brake pads and disks (brake drag), faster, more accurate response to driver commands, easy integration with vehicle dynamic control systems, under-hood space saving through elimination of the vacuum booster and hydraulic systems, tuneable pedal feel and easy- apply parking brake operation. Control is via a dedicated, deterministic communications bus for maximum safety and responsiveness.

"This vehicle is a good illustration of how Delphi is increasingly working with its customers at an early stage in the implementation of new technologies and innovation," says Jose Maria Alapont, president, Delphi Europe, Middle East and Africa and vice president, Delphi Corporation. "We have an excellent relationship with Renault and work closely together in a number of areas of advanced engineering."

A production implementation of Delphi's brake-by-wire technology could include a range of additional features, such as hill-holder control, that can be implemented largely through software. For this next-generation of system, Delphi is integrating much of the control circuitry with the calliper, leading to further space and efficiency benefits.

Delphi has a complete portfolio of environmentally friendly vehicle systems, covering most areas of the vehicle from energy-efficient air conditioning to second-generation diesel common rail. It also has a significant capability in the integration of advanced technologies in concept vehicles for demonstration or engineering development purposes.