An Anti-Lock Braking System is the norm nowadays. In fact, finding a new car without ABS would be a difficult, if not impossible, task. But ABS, though universally present now, isn’t new, as this brief gallop through the system’s history shows.
If asked, say in a pub quiz, when automotive ABS first appeared, what would your answer be? If you said the 1950s, you’d be correct. However, ABS was first developed some 30 years earlier, in 1929 to be exact. The protagonist was the French car and aviation pioneer, Gabriel Voisin, who put together an ABS system for aircraft use.
The 1950s connection lies with the Dunlop Maxaret system, which was introduced during this decade and is still used on some aeroplanes. Maxaret employs a flywheel, drum and valve, attached to the hydraulic feed line that actuates the brake cylinders. The drum is attached to the wheel and normally, it and the flywheel rotate at the same speed. However, if the wheel slows down significantly, the speed difference between the drum and the free-running flywheel operates the valve.
When the valve opens, brake fluid is diverted into a reservoir, effectively cutting the braking force at the wheel. So, the wheel can’t lock. Even this simple, early system resulted in a 30 per cent improvement in braking performance, because the pilots using it would apply full brake pressure, knowing that the skid point would be found automatically – they didn’t waste trying to find it themselves. Burst or burnt-out tyres also became a thing of the past.
While ABS continued to be used on aircraft, its use on cars remained limited. The 1960s saw a fully mechnical system adopted on the Ferguson P99, a racing stablemate of the Ferguson R5, which had four wheel drive, anti-skid braking, electric windows, disc brakes and a hatchback design. Some saw this as the forerunner of the modern car. Around the same time, the Jensen FF had ABS, as did the experimental, all-wheel-drive Ford Zodiac. However, the system was expensive to manufacture and proved unreliable.
ABS reappeared on the 1971 Chrysler Imperial. The Bendix Corporation had teamed up with Chrysler to introduce a computerised three-channel system, with four-sensor, all-wheel ABS – they called it ‘Sure Brake’. It proved to be reliable.
Chrysler was not alone. Also in 1971, General Motors came up with ‘Trackmaster’. This was a rear wheel-only ABS system and was offered as an option on Cadillac cars. Nissan simultaneously offered its Electro Anti-lock System (EAL) on the President model. This was Japan’s first electronic ABS system.
ABS began to grow up in 1975, when Robert Bosch took over Teldix (and all its joint-registered patents). This move was the basis of the ABS system that was marketed some years later.
By 1978, Bosch had joined forces with Daimler Benz. Between themsleves, they developed ABS technology from its early 1970s roots. The resultant multi-channel ABS operated on all four wheels and was completely electronic. Mercedes Benz’s S-Class cars and trucks were the first vehicles on which it was offered.
ABS arrived in the motorcycle sector in 1988, when BMW’s K100 received an electro-hydraulic system. Honda’s Pan European was the next bike to get ABS, in 1992. The Suzuki GSF1 200SA, or Bandit, was introduced with ABS in 2007. Meanwhile, Harley-Davidson made ABS an option on its police motorcycles in 2005. By 2008, the firm made ABS available as an option on its Touring range, while it became standard equipment on selected models.
As is clear, ABS isn’t as new as it seems. In another post, we’ll look at how ABS works. But for now, knowing how the system first came about is valuable information.