CruiseControl

Cruise control is an automotive system that automatically maintains a vehicle’s speed at a chosen set point without the driver having to keep the accelerator pedal pressed. Traditional cruise control focuses on steady speed on clear roads, while newer variants add capabilities such as maintaining a safe following distance.

In operation, the driver engages the system and sets a desired speed with a stalk or switch. A speed sensor monitors actual velocity, and a control unit compares it to the set speed. An actuator adjusts the throttle (and sometimes the fuel delivery or engine torque) to hold or reach the target speed. The system typically disengages when the driver applies the brakes, presses the clutch, shifts into neutral, or activates cancel; many systems also resume the previously set speed after disengagement.

The concept dates to the mid-20th century in the United States. The speed-control idea was developed by inventor Ralph Teetor and was first marketed by the Chrysler Corporation as a cruise control feature in the late 1950s. Since then, cruise control has become common in many vehicles, evolving from purely mechanical or vacuum-based mechanisms to sophisticated electronic controls integrated with engine management systems.

Adaptive cruise control (ACC) is a major development that uses radar, lidar, or cameras to detect traffic ahead and adjust speed to maintain a set following distance. Some ACC systems can bring the vehicle to a complete stop and resume automatically in light traffic. Many modern systems also integrate with other driver-assistance features such as lane-keeping or traffic jam assist.

Usage safety and limitations include reduced effectiveness in heavy traffic, adverse weather, or on winding terrain. Cruise control remains a convenience feature best used on long, straight highways with clear conditions.