Opel Enhances Vectra and Signum with High-Tech Equipment

Press Release

Adaptive IDSPlus chassis system with electronic damping control

Vectra and Signum: More Dynamics, Comfort and Active Safety

• Electronic networking of all driving dynamics systems
• Shock absorbers automatically adjust to road conditions
• Noticeably enhanced driving stability and braking performance
• Sporty calibration of chassis, steering, and acceleration at the touch of a button
• IDSPlus standard with 3.2 V6 ECOTEC and 3.0 V6 CDTI ECOTEC

Driving pleasure and agility are cornerstones of Opel’s brand philosophy and are receiving higher development priority than ever before. Driving on the Nürburgring is, however, the exception to the rule. Much more in demand are everyday, rather subtle driving qualities. Daily commuting or weekend family outings call for soft damping of car body movements for a more comfortable ride. Soft chassis set-ups, however, impede agile handling and performance, and quickly reach their limit in difficult driving situations. Such situations include full load, poor road conditions, fast driving on winding roads, fast lateral accelerations, quick lane changes, or hard braking. This conflict is almost as old as the automobile itself and needs more sophisticated solutions than ever. Following the new Astra, the Vectra and Signum models meet this challenge in a very innovative way.

Electronic Continuous Damping Control (CDC) is a major part of the networked IDSPlus chassis system that Opel now introduces in the Vectra and Signum. This variable damping system automatically reacts to prevailing driving situations, loads, and road conditions. The driver can also choose a sportier setting via the “SportSwitch� located on the instrument panel. IDSPlus is standard in all six-cylinder models with 3.2 V6 ECOTEC and 3.0 V6 CDTI ECOTEC engines, and is optional for cars with the 2.0 turbo ECOTEC and the 150 hp 1.9 CDTI ECOTEC engines.

IDSPlus offers even more dynamics, comfort and active safety

Hans H. Demant, Opel Chairman and Managing Director, and GME Vice President Engineering, has driven many test kilometers with the chassis developers and engineers, and tested the new chassis and safety systems in the various models on the Nürburgring. His conclusion: “Vectra and Signum have superior front-wheel drive suspension with modern MacPherson struts and a sophisticated multi-link rear axle. In conjunction with electronic damping control and the networking of all driving dynamics systems, we are creating new perspectives. As ESPPlus, TCPlus, ABS and CDC do not work alone, but instead constantly communicate with one another via CANbus, it is possible to even further develop potential in terms of driving dynamics, comfort and safety.�

The adaptive damping system CDC in the Vectra and Signum is based on four shock absorbers controlled by solenoid valves, which precisely and continuously adjust the shock absorbers to ideally adapt to road conditions, vehicle movements and driving style within milliseconds. In conjunction with other signals such as speed or accelerator pedal position, three body and two wheel acceleration sensors deliver all information necessary for optimal damping to the control electronics. These in turn calculate the necessary damping force for each wheel using a real time algorithm and send the corresponding electrical signal to the four proportional solenoid valves integrated in the suspension struts and dampers, which regulate oil flow and thereby the damping characteristics.

Main objective: Minimal car body movements

The control algorithm continually calculates speed and the direction of body and wheel movement. The four shock absorbers are then individually set to minimize vehicle movements. Numerous adaptive mechanisms are involved in this process to help register and respond to particular driving maneuvers and road conditions. For example, traction is improved when braking on extremely bumpy or loose-surface roads through reduction of wheel load fluctuation. Rotational tendencies during braking and acceleration maneuvers are almost completely eliminated. As a result, stopping distances on bad roads are reduced by up to five percent.

This is possible by an Integrated Chassis Control (ICC), the networking of all vehicle control systems. CDC damping control, ESPPlus, ABS, and TCPlus as well as the engine and automatic transmission controls constantly communicate via a high-speed databus with a transmission rate of 500 kilobytes per second. This is eight times faster than ISDN (64 kilobytes/second).

Electronic damping control reduces over and understeer

CDC and ESP functions are linked very closely together. This improves cornering and on-the-limit handling, thus raising the balance between comfort and active safety to a new level. CDC constantly monitors the steering angle and yaw rate, but in the event of a critical situation, leaves damping control to ESP. Temporary stiffening of the rear axle shock absorbers increases the car’s readiness to deal with yawing movement, enabling more agile handling. If the driver takes the car close to the handling limit, the damping rates on alternate sides can be varied to counteract over or understeer. This dynamic roll rate adjustment integrated in ESPPlus can be described as a “virtual“ stabilizer in the form of extremely high or low damping forces. If this proves to be insufficient, ESPPlus takes over by controlled braking of one or more wheels. The result is a later and thereby significantly more sensitive ESP activation.

Vectra and Signum drivers also profit from the networked structure of the control systems long before reaching the vehicle’s stability limits. With the help of the SportSwitch located on the instrument panel, drivers can individually change the vehicle’s character in an instant: from a comfortable everyday car to an especially agile machine.

By offering this choice of driving modes, the engineers have created the best of both worlds. The regular setting, which is selected automatically whenever the car is started, has the main objective of keeping body motion to a minimum. The car glides along smoothly, with no hectic or jerky body movements, leaving the driver with a supreme sense of control. The sport mode, on the other hand, focuses on maximal stabilization of the car’s body. In order to achieve this, the damping algorithm is switched over to a second set of parameters. At the same time, the engine responds with more “bite� when accelerating. The electro-hydraulic rack-and-pinion power steering provides more feedback and in conjunction with automatic transmissions, gear shift points are set at higher rpm.