For over a century, the world’s automakers have been refining and improving the way that cars work. Everyone loves when a technological breakthrough brings better performance or fuel economy, but I think some of the greatest advances in automotive engineering have come from safety.
Recently, I visited the Computer History Museum in California. The museum has an exhibit about the on-board ABS computer developed by Bosch that I found interesting.
For decades, automotive manufacturers had recognized the dangers of sending a vehicle into a skid during a hard braking maneuver. There had been early attempts to develop a system that would let you stay in control of the car while stopping, but none of them made it to the assembly line.
In Germany, Mercedes-Benz was working on the problem with Bosch, a huge supplier of automotive electronics. By 1970, engineers from the two companies had figured out a way to monitor wheel lockup using a set of contactless induction speed pickups on the wheels. The signals from these pickups would be evaluated by an electronic unit which would then control the brake pressure via solenoid valves.
The problem was that analog computers required too many parts and were too unreliable to make these calculations. A few years later, the analog unit had been replaced by a completely solid-state transistorized computer.
Starting in December 1978, the world’s first commercially-available electronic anti-lock braking system was available as an option on the Mercedes-Benz S-Class (W116).
This system could pump the brakes 30 times each second, so you can keep control of the vehicle during heavy braking and poor traction. This eliminated the need to “pump the brakes,” which was also called “cadence braking.”
ABS became standard equipment on all Mercedes passenger cars in 1984.
Today, most cars have several computers onboard to control various systems including the engine, brakes, stability control, in-car entertainment, and more. Volvo once bragged that its S80 sedan has over 40 onboard computers, which is more than an F15 fighter jet! But there was once a time when it was a big deal to have a single computer controlling one thing on your car.