“Look Ma, no hands!”
The year 2000 was predicted to be a new dawn of technology that would’ve included fully-autonomous flying cars if the classic Hanna-Barbera cartoon, The Jetsons, was anything to go by. In 1963 R. Buckminster (‘Bucky’) Fuller, inventor, architect, author and futurist predicted that “Man is going to be displaced altogether as a specialist by the computer.” And don’t forget Arthur C.Clarke’s predictions of satellite navigation, adaptive suspension and the often maligned continuously variable-automatic transmission (CVT). Many of the predictions have or are about to come true.
An important contributor to self-driving technology is adaptive cruise control (ACC), an active safety system that automatically controls the acceleration and braking of a vehicle. For the uninitiated, the system is (in most cars) activated by a button on the steering wheel and cancelled when the driver brakes. The system monitors other vehicles and objects on the road and helps to ensure a constant speed and distance from the vehicle in front via speed limit, road curvature and accident data, among others.
Japanese automotive brand Mitsubishi started exploring lidar technology in 1991. Lidar (Light Detection and Ranging) is a remote sensing method that uses light in the form of a pulsed laser to measure ranges (variable distances) to the earth. At the time it was a basic warning system and could not regulate speed. In 1995 however they became the first OEM to offer an adaptive cruise control system, or Preview Distance Control in Mitsubishi parlance, in their Diamante sedan. It included lidar in the front bumper and a miniature camera mounted in the rear-view mirror. This new technology was able to sense when the distance to the vehicle ahead decreased and would automatically depress the accelerator or have the transmission shift down in order to slow the vehicle down. It wasn’t able to operate the brakes though, so when the speed difference with the vehicle in front was too great, it alerted the driver via aural and visual warnings. Due speeds limited to 108 km/h and poor performance in wet conditions Mitsubishi decided to offer the system only in Japan.
In 1999 Mercedes-Benz introduced Distronic on the W220 S-Class. The system was developed with higher speeds on the autobahn in mind but the system also featured its ESP stability control system as standard on all its models. Automatic braking was now included in the technology and it used radar instead of lidar, which was much more cost-efficient.
Originally speed control technology was used by James Watt and Matthew Boulton to control steam engines as far back as 1788. In 1900 Wilson Pilcher invented the Speed Control Device for automobiles and in 1910 the Peerless improved the system by controlling the car’s speed up and downhill as well. In 1948 blind inventor and mechanical engineer Ralph Teetor developed the modern cruise control, officially known as the ‘Speedostat’ on its patent forms. This intelligent system first calculated the ground speed by the rotation of the driveshaft or the speedometer cable. It also used a bi-directional screw-drive and an electric motor to modulate the throttle position as needed.
Teetor’s cruise control, christened ‘Auto-Pilot’, was first offered commercially in the 1958 Chrysler Imperial. Their Cadillac division marketed the product as ‘Cruise Control’ and the rest is automotive history.
In the past few decades adaptive cruise control has evolved from a Level 1 advanced driver-assistance system (ADAS) to a Level 2 one as more manufacturers took this technology on-board. ACC systems now feature more cameras and sensors that can help steer the vehicle automatically to ensure that it also stays within its lane.
We’ve come a long way with modern intelligent cruise control systems focusing on the entire journey resulting a more relaxing and safer drive. Some of the latest ACC systems include:
- Stop and Go cruise control has been designed to stop and start the vehicle in slow-moving traffic
- Eco cruise control minimises the use of energy, resulting in fuel and EV range savings
- Cruise control in curves uses curvature data from the ADAS map to eliminate human intervention
- Turn-by-turn cruise control is able to automate acceleration and braking at highway exists, entrances, junctions and traffic circles
- Predictive adaptive cruise control anticipates road hazards ahead
- Parking speed control ACC systems assist in self-parking and also maneuvering through large parking lots.
- Dynamic priority cruise control is an emerging technology where the system has the ability to automatically handle changing traffic lights and other vehicles at junctions.
It is perhaps difficult to predict where autonomous tech will take the automotive world in the coming years, although judging by how far we have come since the first systems of the ’50s, the possibilities are vast. Hold on tight (or don’t) because at the current rate of automotive development, we’re most certainly in for an interesting ride,,,
Words: Thys de Beer