{"id":268851,"date":"2010-02-03T02:01:17","date_gmt":"2010-02-03T07:01:17","guid":{"rendered":"http:\/\/www.team-bhp.com\/forum\/technical-stuff\/74799-abs-calibration-shortest-braking-distance.html"},"modified":"2010-02-03T02:01:17","modified_gmt":"2010-02-03T07:01:17","slug":"abs-calibration-and-shortest-braking-distance","status":"publish","type":"post","link":"https:\/\/mereja.media\/index\/268851","title":{"rendered":"ABS calibration and shortest braking distance"},"content":{"rendered":"
Before I begin, this is not a "Is it better spend extra on ABS?" thread. We’ve had many of those and the answer is obvious. I’m doing a project on the effectiveness of ABS under differing scenarios and need some help. Yesterday, I was surfing through YouTube and came across this video.<\/p>\n

YouTube – ABS vs. No ABS<\/a><\/p>\n

Very interesting video, isn’t it? Basically, it is saying that ABS systems are calibrated such that their braking is actually not as effective as threshold braking (i.e. braking at constant force just before the point of lock up). In other words, if, theoretically, a driver knew exactly how much the brake pedal could be pressed before lock up, he will be slowing down faster than an identical car equipped with ABS and the brake pedal fully depressed.<\/p>\n

To verify what he’s saying, I’d like to get an idea of exactly how ABS works. My basic idea about ABS was that it would not be engaged until one or more of the wheels locked. At this point, ABS would start "pulsing" the brake pedal at several times per second. In effect, that would create a series of micro-lock ups on and off but because any locked up wheel was almost immediately unlocked, the driver still had steering control. What we’re seeing is that the ABS equipped car’s brake pressure graph would probably be an oscillation; first its too much so the wheel locks, then its too little so it has to apply more pressure if the car is to slow down. The logic behind this video is that a constant braking force is better than the pulsing braking that is done by ABS. <\/p>\n

So here’s what I want to know. <\/p>\n

1) How realistic is it to expect an experienced driver to be able to judge the point of threshold braking such that he beats the ABS system? According to the video, its very much possible but I’d like to get clear hard facts.<\/p>\n

2) How far above and below the threshold braking force does the ABS system pulse? For instance, if say the brake pedal had to be engaged at 70% of its maximum force, the ABS will fluctuate its braking force between (70-x)% and (70+x)%. What is the value of x? And does it vary between different cars? The larger x gets, the better the chances of a driver beating the ABS system.<\/p>\n

If anyone can get me scientific evidence proving or disproving the claims, I’d really appreciate it. Any info on the working of ABS, microsecond by microsecond, would be really useful too. <\/p>\n

Basically, I know its theoretically possible to beat the system when it comes to braking distance and maintaining steering control at the same time, but is practically achieveable? And if ABS does beat the driver all the time, how significantly ahead is an ABS equipped car as opposed to a non ABS car if both are being driven by top class drivers?<\/p>\n

Thanks all! \ud83d\ude42<\/p><\/div>\n","protected":false},"excerpt":{"rendered":"

Before I begin, this is not a "Is it better spend extra on ABS?" thread. We’ve had many of those and the answer is obvious. I’m doing a project on the effectiveness of ABS under differing scenarios and need some help. Yesterday, I was surfing through YouTube and came across this video. YouTube – ABS […]<\/p>\n","protected":false},"author":4624,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[],"class_list":["post-268851","post","type-post","status-publish","format-standard","hentry","category-news"],"_links":{"self":[{"href":"https:\/\/mereja.media\/index\/wp-json\/wp\/v2\/posts\/268851","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/mereja.media\/index\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mereja.media\/index\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mereja.media\/index\/wp-json\/wp\/v2\/users\/4624"}],"replies":[{"embeddable":true,"href":"https:\/\/mereja.media\/index\/wp-json\/wp\/v2\/comments?post=268851"}],"version-history":[{"count":0,"href":"https:\/\/mereja.media\/index\/wp-json\/wp\/v2\/posts\/268851\/revisions"}],"wp:attachment":[{"href":"https:\/\/mereja.media\/index\/wp-json\/wp\/v2\/media?parent=268851"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mereja.media\/index\/wp-json\/wp\/v2\/categories?post=268851"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mereja.media\/index\/wp-json\/wp\/v2\/tags?post=268851"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}