Cruise Control, an Evolving Technology
Efforts by engineers and inventors to assist drivers have come a long way over time. About a hundred years ago, when Cleveland, OH, was the center of auto production in the U.S., the Cleveland-based Peerless Motor Company began putting speed control into its cars. It used a centrifugal governor to maintain speed whether the car was going uphill or down. According to Wikipedia, a centrifugal governor controls the speed of an engine by regulating the amount of fuel admitted to maintain a near constant speed whatever the load or fuel supply conditions. It uses the principle of proportional control.
Wikipedia says that:
Proportional control is how most drivers control the speed of a car. If the car is at target speed and the speed increases slightly, the power is reduced slightly, or in proportion to the error (the actual versus target speed), so that the car reduces speed gradually and reaches the target point with very little, if any, ‘overshoot’, so the result is much smoother control than on-off control.
In 1945, Ralph Teetor, a blind inventor and mechanical engineer, developed modern cruise control (also known as a speedostat). He was inspired to create it after riding in a car driven by his chatty lawyer, who kept speeding up and slowing down as he talked. The 1958 Chrysler Imperial was the first car to be fitted with Teetor’s system, which calculated ground speed based on drive shaft rotations and used a solenoid to vary throttle position as needed. Frank J. Riley invented a “Constant Speed Regulator” and installed it in his car in 1948, then applied for a U.S. patent on it in the 1950s.
Adaptive Cruise Control (ACC) is a more advanced technology that uses forward-looking radar installed behind a vehicle’s grill to determine the speed of the vehicle in front of it, and how far away it is. The ACC automatically adjusts a vehicle’s speed so that it is a safe distance from the one in front of it. And it senses not only the vehicle immediately in front, but ones ahead of it in the same lane. If the lead vehicle in a line of vehicles slows down (or if it finds some other object in the road), the ACC system sends a signal to the engine or braking system of the car at the rear end of the line to lower its speed. Then, once the road is clear, the system re-accelerates the vehicle back to the originally set speed.
As HowStuffWorks.com explains,
The 77-GHz Autocruise radar system made by TRW has a forward-looking range of up to 492 feet (150 meters), and operates at vehicle speeds ranging from 18.6 miles per hour (30 kph) to 111 mph (180 kph). Delphi’s 76-GHz system can also detect objects as far away as 492 feet, and operates at speeds as low as 20 mph (32 kph).
Adaptive cruise control is just a preview of the technology being developed by both companies. These systems are being enhanced to include collision warning capabilities that will warn drivers through visual and/or audio signals that a collision is imminent and that braking or evasive steering is needed.
Automatic braking is another modern auto technology that is making the roads safer. It senses when a crash is about to happen between a car and another vehicle, person, or obstacle, and prevents it by automatically applying the brakes. To detect potential collisions, it uses radar, video, infrared, ultrasonic, or other technologies. GPS sensors enable a vehicle to detect fixed dangers like stop signs up ahead through a location database.
Semi-automatic braking systems assist drivers by warning them via visual and auditory signals, and, when needed, the system activates the brakes at 40% of their power. Once the driver reacts to the signals, he or she can then hit the brakes, applying maximum braking power. If the driver does not react, the pre-crash brake reduces the collision impact.
A fully automatic braking system improves on a semi-automatic one by automatically braking a car with maximum power to avoid a collision. A fully automatic braking system does not require a driver’s help.
Another recent development is Volkswagen’s Temporary Autopilot System that makes it possible for drivers to set the speed and then sit back and let the car basically drive itself. It uses lane monitoring, speed detection, and scans the road ahead for other vehicles. Drivers need not worry, because they are always free to take control of the car at any time, as the automatic system can be instantly overridden.
As Hunter Skipworth writes for Pocket-lint,
Volkswagen has said that unlike previous attempts at automated driving, this new system is based on production level hardware, meaning we might see it come to fruition. The system forms a good jumping off point between current assistance systems and totally driverless vehicles, like the Toureg nicknamed Stanley which has crossed entire deserts alone.
Of course, as with any technology, there are always times when things will go wrong. Last Saturday, police officers at Huntsville, Texas, Sam Houston State University came to the rescue of a driver whose car’s cruise control went out of control. Galin Jeter, 21, had set the cruise control in his family-owned 2001 Ford Expedition at 60 miles an hour. When a truck pulled in front of him, Jeter hit the brakes, but his car would not slow down.
As Brandon Scott reports Jeter saying in The Huntsville Item,
‘They (brakes) were locked, like I couldn’t push them in,’ he said. ‘I tried to hit the off button because I knew I had cruise control on, but it wouldn’t shut off. Luckily, the truck sped up, but I tried the gear shift, the keys, emergency brake. I tried everything and none of it worked.’
Jeter, an aspiring theologian, said he still gets goosebumps thinking about what happened. ‘I’m still shaken over it,’ he said. ‘I told (dispatch), “Look I’m about to hit downtown Huntsville and I cannot get this car to stop. I need somebody out here.” I told her there was going to be an accident and this was going to get ugly.’
University police officer Rocky Carrell had reached the end of his shift when he heard what was happening over the police scanner. Carrell drove his SUV squad car to where Jeter was driving and then pulled in front of Jeter. According to the accident report, Jeter’s vehicle struck the police car from the rear numerous times, knocking off its bumper before coming to a stop.
And as The Huntsville Item‘s report continues:
‘He just immediately ran up and threw his arms around me like we had known each other for years,’ Carrell said of Jeter’s reaction. ‘He was just ecstatic and quite relieved. I was more pumped about the aftermath of what would have happened if we couldn’t have got this done.’
Jeter, who leaves for Southwestern Baptist Theological Seminary in Fort Worth on Aug. 22, said the back of his neck was swollen from the impact from the accident. He was tested for broken bones at Huntsville Memorial Hospital on Monday. Jeter added that his family plans to get an explanation as to why the vehicle would malfunction in such a way.