Autonomous cruise control system

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Schematic of Intelligent Cruise Control. The red car automatically follows the blue car.

Adaptative cruise control (ACC) is a cruise control system in some modern vehicles. The system also goes under the names of active cruise control (ACC) or intelligent cruise control (ICC). These systems use either a radar or laser setup to allow the vehicle to slow when approaching another vehicle and accelerate again to the preset speed when traffic allows. ACC technology is widely regarded as a key component of any future generations of smart cars, as a form of artificial intelligence that may usefully be employed as a driving aid.

1 Types
2 Available systems
- 2.1 Examples of vehicles with adaptive cruise control
3 See also

[edit] Types

Laser-based systems are significantly lower in cost than radar-based systems; however, laser-based ACC systems do not detect and track vehicles well in adverse weather conditions nor do they track extremely dirty (non-reflective) vehicles very well. Laser-based sensors must be exposed, the sensor (a fairly-large black box) is typically found in the lower grill offset to one side of the vehicle.

Radar-based sensors can be hidden behind plastic fascias; however, the fascias typically looks different from a vehicle without the feature. For example, Mercedes packages the radar behind the upper grill in the center; however, the Mercedes grill on such applications contains a solid plastic panel in front of the radar with painted slats to simulate the slats on the rest of the grill.

Radar-based systems are available on many luxury cars as an option for approx. 1000-3000 USD/euro. Laser-based systems are available on some near luxury and luxury cars as an option for approx. 400-600 USD/euro.

Some systems also feature forward collision warning or Collision Mitigation Avoidance System, which warns the driver and/or provides brake support if there is a high risk of a rear-end collision.

[edit] Available systems

Jaguar Cars and Mercedes-Benz were the first to offer radar-based systems in 1999. Similar adaptive systems are now offered by other manufacturers. For 2006, Mercedes-Benz refined the Distronic system to completely halt the car if necessary (now called 'Distronic Plus' and offered on their S-Class range of luxury sedans), a feature now also offered by Bosch as 'ACC plus' and available in the Audi Q7. In an episode of Top Gear, Jeremy Clarkson demonstrated the effectivness of the cruise control system in the S-class by coming to a complete halt from motorway speeds to a round-about and getting out, all without touching the pedals. He was astonished. Earlier he said, "What am I here for!?", when sitting in the driver's seat.

Toyota's Lexus vehicles was the first to bring laser-based systems to the US market with the 2001 Lexus LS430 "DLCC" (Dynamic Laser Cruise Control).[1] Lexus then offered laser-based systems on its RX and radar-based systems on its IS, ES, GS and LS models.

Several Japanese manufacturers first offered ACC systems in the Japanese market in the late 1990s. These early systems did not apply the brakes and only controlled speed through throttle control and downshifting. However, this was changed with the Acura RL. It features Collision Mitigation Braking System, which can alert drivers of objects up to 100 m ahead, if the distance is less, it brakes slightly and tugs at the seatbelts. In case of no driver reaction, the RL retracts, locks the seatbelts and brakes hard. A similar system is offered in the Lexus LS430/460.