While there certainly are drivers who knowingly exceed the speed limit, many others aren't even aware that they're doing so. Given that using cruise control isn't all that practical when driving around town, Ford has instead introduced the Intelligent Speed Limiter. The technology will debut on the newest incarnation of the automaker's S-Max vehicle.
Drivers begin by activating the system and manually entering the maximum speed at which they wish to travel, using controls on the steering wheel. Should they subsequently start to exceed that limit, the system will slow them back down by electronically limiting the fuel flow – this is safer than simply applying the brakes.
Because the brakes aren't involved, however, this does mean that drivers could unintentionally start speeding when coasting downhill. If that does happen, they're notified by an audible warning. In the event that they do temporarily need to go faster, such as when passing another vehicle on the highway, the Intelligent Speed Limiter can be overridden simply by pressing firmly on the accelerator.
Given that posted speed limits can change within one trip, the system also utilizes a windshield-mounted camera that watches for road signs using Ford's Traffic Sign Recognition System. When a speed limit sign is spotted and read, the car's speed limit is adjusted up or down accordingly.
In locations such as rural roads, however, speed limits may not be posted all that frequently. Should that be the case, the Intelligent Speed Limiter can also obtain speed limit data from maps on the vehicle's navigation system.
More information is available in the following video.
Source: Ford