The second-generation Citroen C4 features Robert Bosch GmbH’s new lane-change-assist technology, marking the first time the system has been used on a production model. Although similar systems have been on the market for years, the Bosch system uses ultrasonic detection methods.
The system uses two rear-side sensors to detect objects up to 3 meters to the side or diagonally to the rear of the vehicle, which includes blind spots. Should an object be detected the system activates a light on the sideview mirror on the same side as that object. If the driver ignores the warning and signals to change lanes, the system sounds an alarm. Two front sensors prevent the system from “crying wolf” by scanning for vehicles ahead. If, for example, the front right sensor detects an object before the rear right sensor, the system decides the object is probably being overtaken and hence clearly visible to the driver, requiring no alarm. The Bosch technology functions at speeds between 10-140 kph (6-87mph).
Inadequate observation when changing lanes is a frequent cause of accidents. When driving at high speed the consequences can be severe. This danger has been reduced by systems that use radar/video camera monitoring to alert the driver to any obstacles when changing lanes. However, Bosch believes that its new ultrasonic system will surpass those of rivals, due to its cheaper price.
In addition to lane-change assist, the C4 has many other features to aid the driver. Bosch contributes further by supplying the ABS and ESC braking systems, helping bring the vehicle to a controlled stop in the event of sudden braking. U.S.-based Gentex Corp. contributes the auto-dimming interior mirror, which reduces the risk of the driver being dazzled by headlamp glare. The mirror comprises an electrochromic gel sandwiched between two glass layers. If excessive illumination is detected, the system applies an electric current to the gel causing it to dim, by virtue of its chemical properties. Luxembourg-based supplier IEE SA encourages the driver to buckle-up with its seat-belt reminder technology, while Italy’s Magneti Marelli S.p.A. helps drivers find their way by equipping the C4 with a navigation system.
Other noteworthy suppliers include AGC Automotive Europe, which provides the automobile’s prominent panoramic sunroof. TI Automotive won several important contracts, including the fuel tank and related components. It produces the fuel tank at its plant in Ettlingen, Germany. French supplier Michelin contributes its energy-saving tires to the C4.
Last October, Citroen premiered the five-door C4 at the Paris auto show, alongside the sportier three-door DS4. The C4 is made available with Citroen’s new micro-hybrid e-HDi powertrains, featuring stop-start technology. Citroen produce the new C4 at its plant in Mulhouse, France.