Ever wonder how a car’s cruise control works? Well, wonder no longer. Cruise Control, on this Moment of Science. Cruise control adjusts the throttle position, which controls the speed of the car by limiting how much air gets into the engine. Rather than the driver pushing his foot on the pedal, the cruise control presses it for you.
Instead of your foot opening the throttle, cruise control uses something called an actuator to adjust the throttle and maintain speed. It’s all computerized. There’s a small computer under the hood or behind the dashboard. It uses sensors to monitor the speed of the car, the speed you want to achieve, and the throttle position.
If you’re going 50 miles per hour and you set the cruise control for 60, the computer registers the current speed of the car and calculates how much it needs to open the throttle until you reach 60. If you’re going up a hill and the car starts to slow, the computer senses that and adjusts the throttle to maintain speed.