Modern cruise control began to emerge in the 1990s, with advanced digital technology incorporated into the design.
How does it work?
By actively adjusting the car’s throttle, cruise control works to maintain the speed of the car without needing the driver to do anything. In mechanical setups, the system activates the throttle valve with a cable connected to an actuator, which ensures the engine generates enough power to maintain its current speed. However, in newer cars, that use a drive-by-wire throttle body, cruise control is completely electronic. This results in a more predicative system, whereby it can slow down or speed up depending on what the target speed is. It also allows the driver to increase or decrease their speed, usually using buttons on the steering wheel.
The driver, of course, can decide when to use cruise control. They are also in charge of what speed the car will cruise at. After turning the system on, the driver then must set the speed. In some cars, the system will cruise at the current speed, in others it might need to be set. To deactivate the system, the driver must simply press the brake or clutch pedal or cancel it using a button that usually found on the steering wheel.
Different types of cruise control
The examples above are the most simple applications of cruise control, more advanced types of cruise control do exist, though — one of which is most commonly called adaptive cruise control. Cars fitted with an adaptive cruise control system use a forward-looking radar sensor to detect the speed and proximity of the car ahead. It then uses that information to adjust its own speed and keep it at a safe distance.
When the car ahead slows down, so will the car fitted with adaptive cruise control. When the car ahead speeds up, the cruise control will increase the vehicle's speed until it hits its set limit. If you want to dive even deeper into this topic, we’ve written about it before — click here for that article.
There are a many different types of adaptive cruise control – radar-based systems, laser-based systems, binocular computer vision systems, assisting systems, multi-sensor systems and predictive systems. The first two are self-explanatory – using radar and laser systems to detect the vehicles surroundings, as opposed to binocular computer vision which uses cameras in the vehicle’s rearview mirror. Other versions, such as assisting systems, can be bought separately to enhance the safety features that the car already has. Predictive systems use data in order to predict the movement of other vehicles.
The type of cruise control fitted varies from vehicle to vehicle, so it pays to know what type of system your car has so you can understand its capabilities. There are limitations, both with adaptive cruise control and conventional cruise control. The driver must still pay attention at all times and not let their awareness drift. Weather conditions such as snow, rain or fog could also confuse the sensors and adversely affect the adaptive cruise control system.