ABS: More important than you’d think
Last weekend I visited Bosch in Stuttgart. The purpose of the visit was to learn about their opportunities for studying and interning. We listened to a presentation about the company in the morning, and then toured the research and development facility in Stuttgart during the afternoon. We weren’t allowed to take pictures, so this post is only going to be text, but we certainly had an interesting visit.
Bosch is one of the pioneers of ABS, which is the anti-lock braking system on a car. It actually stands for Antiblockiersystem, which is the German term. In case you’ve been living with your head in the clouds, ABS prevents your wheels from locking by automatically disengaging and re-applying your brakes when they lock up. This prevents the wheels from staying locked and sliding without traction. Bosch now has an upgraded technology called ESP, which is an electronic stability program (Elektronisches Stabilitätsprogramm). ESP is basically ABS on steroids, and can control braking and acceleration to all four wheels from measurements of steering wheel input, vehicle yaw movement and independent wheel speed. ESP drastically improves a driver’s ability to handle a car in an emergency situation.
Before this weekend, I had heard more than one person claim that they disliked ABS. Once was someone claiming that she just wanted to “lock those brakes up and screech to a halt.” Another didn’t like the way the pedal felt when ABS engaged, that it felt like things were grinding and breaking. I had always known that ABS was good since it allowed for handling while braking. If your wheels are locked and sliding, there is no way that turning them is going to make them slide in a different direction, that much is obvious. But to fully experience the advantage of ABS, one needs to see it in action, which is exactly what I did at the Bosch test-track in Stuttgart.
When we went out to the track, we were shown three tests. The car was a Mercedes S-Class from the late 90s. The first test was handling. The car was going to stop on wet pavement from about 60 km/h (37 mph) and try to swerve to avoid hitting a line of cones. Without ABS, the car slid straight through the cones even though the wheels were turned. With ABS, the car was able to brake and avoid the cones at the same time.
The second test was of stopping on dry pavement from about 100 km/h (62 mph). This had the most amazing results. ABS reduced the stopping distance to about half of what it was without ABS. It’s never been really clear to me that ABS would actually reduce stopping distance. I knew it was always a question of which surfaces had more kinetic friction, the wheels on the pavement or the brake pads, but now it’s clear that it’s better to have the wheels not sliding on the pavement.
The third test was the most fun, we got to ride in the car for this one. Basically, this test was just to compare performance braking on wet pavement at high speeds (120 km/h or 75 mph). We hit the brakes at that speed and just try to stop as quickly as possible. With ABS, the car comes to a safe stop, but when there is no ABS, the car spins wildly out of control and doesn’t stop until much further. Spinning out of control at 75 mph on a test-track is actually quite relaxing, since you don’t really feel anything, but I’m sure in a real-world situation, you’d be absolutely terrified. All in all, Bosch is a pretty cool company. Aside from introducing new technology into the automotive industry, their products help keep you and I safe on the road. After experiencing that demo, I wouldn’t drive a car without ABS.