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I did a anti-slip course where we learned dosed breaking to reduce break distance. And once a circuit racing course where the instructor just told me to break w

I did a anti-slip course where we learned dosed breaking to reduce break distance. And once a circuit racing course where the instructor just told me to break with all force available. The latter stuck. This instructor logic was, only if you are a pro driver you actually can outperform ABS. In emergency situations I break with full force without hesitation. This has lead to multiple avoided crashes and TBH two back collisions. Once I pushed so hard the break light sensor had to be replaced. In that case I saw a SUV struggling to stop in my rear view mirror. I had enough control to move to the right and have that SUV crash into the vehicle in front of me. In this line of thought, it can be life saving to be overweight. I was about 120 kg back then and therefor had quite strong legs.

JohnBooty 3y ago
I got really good at pumping the brakes (is that "dosed braking"? new term to me) in the days before ABS. You can definitely get close to the performance of ABS with practice. Used to practice in the snow, in empty parking lots. (ABS or no ABS, everybody should safely practice recovering from spins and slides in empty parking lots! It's also really fun...) The idea that a pro could outperform ABS is surprising to hear. I guess one area where a pro could outperform ABS is if you are trying to slow, not stop. All the ABS systems I've used seem to assume you're trying for a full stop. Anyway, I'm really glad we have ABS now.
- deleted 3y ago
  [deleted]
- david_acm 3y ago
  I believe the term "pumping the brakes" refers to applying and releasing pressure on the brakes. With ABS off, a tire that's locked up (not spinning) will stop in a significantly longer distance than one that's at the limit of grip (slipping with a slight under-rotation). Assuming you have exceeded the limit of grip of the tires with the initial brake bite and the tires have started to lock up, by releasing and reapplying pressure you allow the tire to spin up again to regain grip and then apply more brake to help stop the car. I assume this was to kinda emulate what ABS is meant to do (albeit much slower?) but I never knew this was a thing until recently. You do not need to pump the brakes if you can threshold brake, though I understand the fact that the vast majority of drivers on the road cannot do this and ABS is a life-saving fallback. Also to add to your comment about everyone taking some time to practice. I would also 100% recommend a good racing simulator if you or a friend you know has one. Specifically a setup that has a load cell braking pedal. Most entry-level sim pedals are potentiometers which measure the distance your foot travels as opposed to a load cell which measures the force applied on the pedal. This is how my younger self learned to threshold brake (among other things) and I was surprised at how it all transferred to the real world when I finally hit the track later in life.
  - cwillu 3y ago
    Amusingly, a loadcell is in fact a very precise measurement of how far something has travelled in response to a load. More specifically, a resistor changes value very slightly as it is compressed or expanded. If you laminate a resistor to a strip of metal, you can use that change in resistance to measure the deflection, and then derive the force that drove that deflection. In principal you can get the same information with a lever attached to the same strip connected to a potentiometer; indeed, lever scales based on amplifying the deflection like that used to be universally used. Source: I was a loadcell technician in a previous life.
  - JohnBooty 3y ago
    That's really cool and informational. Thanks for posting that. And yeah, pumping the brakes was essentially the "manual" version of ABS. Depressing and releasing as rapidly as possible.
- cf100clunk 3y ago
  Prior to commonplace ABS in cars, pumping the brakes when traction was bad was a commonplace braking technique taught across Canada for winter driving. An added benefit was that the sudden, irregular flashes of brake lights ahead hopefully gave a good amount of warning to following drivers to let off their own gas pedal and do the same kind of brake pumping.
- timthorn 3y ago
  > I got really good at pumping the brakes (is that "dosed braking"? new term to me) in the days before ABS. I always understood the term was cadence braking; that might be UK terminology though.
97-109-107 3y ago
I found a lot of humor in your anecdote that the light sensor had to be replaced. In a similar vein, a family member had a hardware issue in their laptop where some keys would not register some of the time (moisture). Their understanding was that they did not press hard enough for the device to register the press. This confusion between the boundaries of electronic and mechanical problems led to some mocking. If your anecdote can be taken at face value - they could find some respite in the fact that by pressing the keys too hard they could damage some peripheral electronic parts.
- j-a-a-p 3y ago
  I can dig deeper behind my face. It was a Volvo 850. After the incident the brake lights kept on. I had to repair the car twice. The first responding mechanic had a single sensor that sort of fitted. A few days later I had my regular mechanic replace it with the stock double sensor. IIRC this model has one sensor for the brake lights and one for the cruise control.
tass 3y ago
In a modern (<10 year old) car I question the "pro driver" result. I've been looking for data on this, and haven't seen anything that says this is true, but have seen the opposite. In the past, this was likely true when ABS systems weren't able to control individual wheels. They can do that today, can check for wheel lock-ups and react dozens of times a second, and can therefore compensate for changing grip at different parts of the road during the entire stopping process. In formula 1, where ABS has been banned, drivers have the capability to manually adjust brake balance (front/back and left/right) which they can do for each corner - so in this scenario it is true but only because they are given an advanced control, practice it over and over for the specific corner, and aren't allowed to use ABS to begin with.
- iokanuon 3y ago
  This video is about motorcycles, not cars. Also, the data on this is in the linked video - the author demonstrates you can do a controlled stoppie to decelerate faster without ABS, because that's its main feature - preventing you from flying off the bike.
  - tass 3y ago
    I've seen the video, but the comment I'm replying to seems to be referring to a car driving course. I'm a little surprised there's no "pro ABS" for motorcycles which allows you to do a stoppie if you enable an option, and/or are keeping the bike perfectly straight.
    - sudosysgen 3y ago
      There is, that specific bike has it and it's really close to the best performance you can get as an expert. But it's not very common
- labcomputer 3y ago
  > In a modern (<10 year old) car I question the "pro driver" result. I've been looking for data on this, and haven't seen anything that says this is true, but have seen the opposite. There is an old SAE paper published by Chrysler that I can't find at the moment. IIRC, it was published in 1968 or 1969, and evaluated their new all-wheel[1] ABS system (later to be sold on the 1969-1973 Imperial). The gist of it is that on most surfaces relevant passenger cars, ABS gives somewhat ~shorter~ [Edit: longer ] stopping distances but the difference is minimal compared to a trained professional driver, and both are significantly shorter than locking the wheels (what a non-pro is likely to do in a panic situation) On ice, locking the wheels produces stopping distances that are several times greater than threshold braking. Wet pavement (especially asphalt) is better for ABS, too, though not as extreme as ICE. Importantly, threshold braking also enables the driver to maintain directional control on all surfaces, especially when the left and right wheels have different amounts of traction. ABS enables the driver to concentrate on steering while the computer adjusts the brakes. However, on dry concrete, as well as gravel or snow, locking the wheels does produce somewhat shorter stopping distances. (Concrete tends to be aggressively textured, almost like sandpaper; gravel and snow can build up a "ramp" ahead of a locked wheel) The only problem with locking for emergency stops is that 1) you wear the tires down to the cords after about 10 such emergency stops from 60 mph on dry concrete; and 2) the vehicle tends to spin. If the driver should happen to back off the brake pressure while partially spun, the vehicle will depart the road before they can react... so if you're going to lock the wheels, you have to really commit to it. [1] Chrysler had 4-wheel ABS 10 years before Mercedes' "first car in the world with 4-wheel ABS", but Chrysler had computer logic to release brake pressure on both rear wheels if either one slipped (it had sensors in both rear wheels), which is how Mercedes was able to claim a "first" with their system that simply treated both rear wheels independently.
rqtwteye 3y ago
"In emergency situations I break with full force without hesitation. This has lead to multiple avoided crashes and TBH two back collisions. Once I pushed so hard the break light sensor had to be replaced." I think full braking should be part of driver training. A lot of people I know are very hesitant to brake full force and I think a lot of accidents happen because people don't really brake all out when needed. As far as driver training goers, a little training in sliding would also be very helpful so people know what to do when the car has understeering or oversteering.
- saalweachter 3y ago
  There are a lot of knock-on effects. For instance, a lot of drivers prefer to swerve rather than brake ... because they're afraid of getting hit from behind, because everyone is tail-gating.
  - david_acm 3y ago
    For this precise reason I like to drive with tons of buffer to the car ahead. Given the fact that I am usually in a sports car, I know I can brake much faster than most people around me. Should I need to come to a complete stop, I can control the braking distance to make sure the cars behind me are not only aware that I'm coming to a full stop, which gives them the time/distance they need to brake, but it also gives me time to react to them should they fail to see me slowing down (not paying attention). An added bonus is that most of time the impatient drivers will just go around me and I don't need to worry too much about tailgaters.
    - aidenn0 3y ago
      > An added bonus is that most of time the impatient drivers will just go around me and I don't need to worry too much about tailgaters. I so wish this were more true; I've been tailgated for 10s of miles in the right lane on a freeway with light traffic that was never fewer than 3 lanes for the entirety of that distance.
      - 3y ago
taylodl 3y ago
When driving a car with ABS, all-out braking is the best option. You'll get the quickest, safest stop. That same strategy doesn't work as well on a motorcycle equipped with ABS as you still need to preload the front tire before applying full braking power. As the video shows, this minimizes your stopping distance. Like a car, once you're fully on the brake then stay on it - the ABS system will take care to prevent wheel lockup and skid.
pdonis 3y ago
> In that case I saw a SUV struggling to stop in my rear view mirror. I had enough control to move to the right and have that SUV crash into the vehicle in front of me. As this example of yours shows, a key benefit of ABS (if you're not a professional driver) is that it allows you to steer as well as brake, by preventing the wheels from locking). IIRC studies have shown that the majority of accidents cannot be avoided by braking alone even with an optimal stopping distance; you need to be able to steer as well.
- NikolaNovak 3y ago
  This. In advanced driving lessons, in both dry and snowy conditions, goodn driving instructors not only acknowledged but demonstrated, it is POSSIBLE to break better than ABS. But in an uncontrolled, unanticipated emergency (where you don't necessarily get to pick your breaking point and posture etc), ABS gives you steering control. It takes practice to utilize that ability, mostly people just focus and fixate in the obstacle ahead of them they are trying to not hit. But the miraculous, magical ability to steer with ABS is an absolute life saver.
  - j-a-a-p 3y ago
    > mostly people just focus and fixate in the obstacle ahead Indeed! Forgot all about my takeaway #2 of the course, thanks for reminding me. People tend to focus wrong in an emergency. Look further ahead, get the bigger picture otherwise you actually steer toward the collision as a self fulfilling prophecy.
chrisweekly 3y ago
nit: "brake" (stopping force), not "break" (damage)
taneq 3y ago
> only if you are a pro driver you actually can outperform ABS I'd imagine even then, this only applied 20 years ago when ABS was still relatively primitive. I've had only triggered the ABS on my ~2015 car a couple of times but I don't think I could have done significantly better than it even in a non-panic situation.
serf 3y ago
>In this line of thought, it can be life saving to be overweight. I was about 120 kg back then and therefor had quite strong legs. people that lack the ability to lock the wheels on their vehicle on-demand shouldn't be driving it without aids. it's exclusionary, but even as a paralyzed person who is mandated to use hand controls for throttle and brake it was expected of me to demonstrate that I could leverage enough force on the brake pedal to initiate lock-up in a timely manner -- and modern cars with power-assist brakes should have little problem doing so.

JohnBooty 3y ago

I got really good at pumping the brakes (is that "dosed braking"? new term to me) in the days before ABS. You can definitely get close to the performance of ABS with practice. Used to practice in the snow, in empty parking lots. (ABS or no ABS, everybody should safely practice recovering from spins and slides in empty parking lots! It's also really fun...) The idea that a pro could outperform ABS is surprising to hear. I guess one area where a pro could outperform ABS is if you are trying to slow, not stop. All the ABS systems I've used seem to assume you're trying for a full stop. Anyway, I'm really glad we have ABS now.

deleted 3y ago
[deleted]
david_acm 3y ago
I believe the term "pumping the brakes" refers to applying and releasing pressure on the brakes. With ABS off, a tire that's locked up (not spinning) will stop in a significantly longer distance than one that's at the limit of grip (slipping with a slight under-rotation). Assuming you have exceeded the limit of grip of the tires with the initial brake bite and the tires have started to lock up, by releasing and reapplying pressure you allow the tire to spin up again to regain grip and then apply more brake to help stop the car. I assume this was to kinda emulate what ABS is meant to do (albeit much slower?) but I never knew this was a thing until recently. You do not need to pump the brakes if you can threshold brake, though I understand the fact that the vast majority of drivers on the road cannot do this and ABS is a life-saving fallback. Also to add to your comment about everyone taking some time to practice. I would also 100% recommend a good racing simulator if you or a friend you know has one. Specifically a setup that has a load cell braking pedal. Most entry-level sim pedals are potentiometers which measure the distance your foot travels as opposed to a load cell which measures the force applied on the pedal. This is how my younger self learned to threshold brake (among other things) and I was surprised at how it all transferred to the real world when I finally hit the track later in life.
- cwillu 3y ago
  Amusingly, a loadcell is in fact a very precise measurement of how far something has travelled in response to a load. More specifically, a resistor changes value very slightly as it is compressed or expanded. If you laminate a resistor to a strip of metal, you can use that change in resistance to measure the deflection, and then derive the force that drove that deflection. In principal you can get the same information with a lever attached to the same strip connected to a potentiometer; indeed, lever scales based on amplifying the deflection like that used to be universally used. Source: I was a loadcell technician in a previous life.
- JohnBooty 3y ago
  That's really cool and informational. Thanks for posting that. And yeah, pumping the brakes was essentially the "manual" version of ABS. Depressing and releasing as rapidly as possible.
cf100clunk 3y ago
Prior to commonplace ABS in cars, pumping the brakes when traction was bad was a commonplace braking technique taught across Canada for winter driving. An added benefit was that the sudden, irregular flashes of brake lights ahead hopefully gave a good amount of warning to following drivers to let off their own gas pedal and do the same kind of brake pumping.
timthorn 3y ago
> I got really good at pumping the brakes (is that "dosed braking"? new term to me) in the days before ABS. I always understood the term was cadence braking; that might be UK terminology though.

97-109-107 3y ago

I found a lot of humor in your anecdote that the light sensor had to be replaced. In a similar vein, a family member had a hardware issue in their laptop where some keys would not register some of the time (moisture). Their understanding was that they did not press hard enough for the device to register the press. This confusion between the boundaries of electronic and mechanical problems led to some mocking. If your anecdote can be taken at face value - they could find some respite in the fact that by pressing the keys too hard they could damage some peripheral electronic parts.

j-a-a-p 3y ago
I can dig deeper behind my face. It was a Volvo 850. After the incident the brake lights kept on. I had to repair the car twice. The first responding mechanic had a single sensor that sort of fitted. A few days later I had my regular mechanic replace it with the stock double sensor. IIRC this model has one sensor for the brake lights and one for the cruise control.

tass 3y ago

In a modern (<10 year old) car I question the "pro driver" result. I've been looking for data on this, and haven't seen anything that says this is true, but have seen the opposite. In the past, this was likely true when ABS systems weren't able to control individual wheels. They can do that today, can check for wheel lock-ups and react dozens of times a second, and can therefore compensate for changing grip at different parts of the road during the entire stopping process. In formula 1, where ABS has been banned, drivers have the capability to manually adjust brake balance (front/back and left/right) which they can do for each corner - so in this scenario it is true but only because they are given an advanced control, practice it over and over for the specific corner, and aren't allowed to use ABS to begin with.

iokanuon 3y ago
This video is about motorcycles, not cars. Also, the data on this is in the linked video - the author demonstrates you can do a controlled stoppie to decelerate faster without ABS, because that's its main feature - preventing you from flying off the bike.
- tass 3y ago
  I've seen the video, but the comment I'm replying to seems to be referring to a car driving course. I'm a little surprised there's no "pro ABS" for motorcycles which allows you to do a stoppie if you enable an option, and/or are keeping the bike perfectly straight.
  - sudosysgen 3y ago
    There is, that specific bike has it and it's really close to the best performance you can get as an expert. But it's not very common
labcomputer 3y ago
> In a modern (<10 year old) car I question the "pro driver" result. I've been looking for data on this, and haven't seen anything that says this is true, but have seen the opposite. There is an old SAE paper published by Chrysler that I can't find at the moment. IIRC, it was published in 1968 or 1969, and evaluated their new all-wheel[1] ABS system (later to be sold on the 1969-1973 Imperial). The gist of it is that on most surfaces relevant passenger cars, ABS gives somewhat ~shorter~ [Edit: longer ] stopping distances but the difference is minimal compared to a trained professional driver, and both are significantly shorter than locking the wheels (what a non-pro is likely to do in a panic situation) On ice, locking the wheels produces stopping distances that are several times greater than threshold braking. Wet pavement (especially asphalt) is better for ABS, too, though not as extreme as ICE. Importantly, threshold braking also enables the driver to maintain directional control on all surfaces, especially when the left and right wheels have different amounts of traction. ABS enables the driver to concentrate on steering while the computer adjusts the brakes. However, on dry concrete, as well as gravel or snow, locking the wheels does produce somewhat shorter stopping distances. (Concrete tends to be aggressively textured, almost like sandpaper; gravel and snow can build up a "ramp" ahead of a locked wheel) The only problem with locking for emergency stops is that 1) you wear the tires down to the cords after about 10 such emergency stops from 60 mph on dry concrete; and 2) the vehicle tends to spin. If the driver should happen to back off the brake pressure while partially spun, the vehicle will depart the road before they can react... so if you're going to lock the wheels, you have to really commit to it. [1] Chrysler had 4-wheel ABS 10 years before Mercedes' "first car in the world with 4-wheel ABS", but Chrysler had computer logic to release brake pressure on both rear wheels if either one slipped (it had sensors in both rear wheels), which is how Mercedes was able to claim a "first" with their system that simply treated both rear wheels independently.

rqtwteye 3y ago

"In emergency situations I break with full force without hesitation. This has lead to multiple avoided crashes and TBH two back collisions. Once I pushed so hard the break light sensor had to be replaced." I think full braking should be part of driver training. A lot of people I know are very hesitant to brake full force and I think a lot of accidents happen because people don't really brake all out when needed. As far as driver training goers, a little training in sliding would also be very helpful so people know what to do when the car has understeering or oversteering.

saalweachter 3y ago
There are a lot of knock-on effects. For instance, a lot of drivers prefer to swerve rather than brake ... because they're afraid of getting hit from behind, because everyone is tail-gating.
- david_acm 3y ago
  For this precise reason I like to drive with tons of buffer to the car ahead. Given the fact that I am usually in a sports car, I know I can brake much faster than most people around me. Should I need to come to a complete stop, I can control the braking distance to make sure the cars behind me are not only aware that I'm coming to a full stop, which gives them the time/distance they need to brake, but it also gives me time to react to them should they fail to see me slowing down (not paying attention). An added bonus is that most of time the impatient drivers will just go around me and I don't need to worry too much about tailgaters.
  - aidenn0 3y ago
    > An added bonus is that most of time the impatient drivers will just go around me and I don't need to worry too much about tailgaters. I so wish this were more true; I've been tailgated for 10s of miles in the right lane on a freeway with light traffic that was never fewer than 3 lanes for the entirety of that distance.
    - 3y ago

taylodl 3y ago

When driving a car with ABS, all-out braking is the best option. You'll get the quickest, safest stop. That same strategy doesn't work as well on a motorcycle equipped with ABS as you still need to preload the front tire before applying full braking power. As the video shows, this minimizes your stopping distance. Like a car, once you're fully on the brake then stay on it - the ABS system will take care to prevent wheel lockup and skid.

pdonis 3y ago

> In that case I saw a SUV struggling to stop in my rear view mirror. I had enough control to move to the right and have that SUV crash into the vehicle in front of me. As this example of yours shows, a key benefit of ABS (if you're not a professional driver) is that it allows you to steer as well as brake, by preventing the wheels from locking). IIRC studies have shown that the majority of accidents cannot be avoided by braking alone even with an optimal stopping distance; you need to be able to steer as well.

NikolaNovak 3y ago
This. In advanced driving lessons, in both dry and snowy conditions, goodn driving instructors not only acknowledged but demonstrated, it is POSSIBLE to break better than ABS. But in an uncontrolled, unanticipated emergency (where you don't necessarily get to pick your breaking point and posture etc), ABS gives you steering control. It takes practice to utilize that ability, mostly people just focus and fixate in the obstacle ahead of them they are trying to not hit. But the miraculous, magical ability to steer with ABS is an absolute life saver.
- j-a-a-p 3y ago
  > mostly people just focus and fixate in the obstacle ahead Indeed! Forgot all about my takeaway #2 of the course, thanks for reminding me. People tend to focus wrong in an emergency. Look further ahead, get the bigger picture otherwise you actually steer toward the collision as a self fulfilling prophecy.

chrisweekly 3y ago

nit: "brake" (stopping force), not "break" (damage)

taneq 3y ago

> only if you are a pro driver you actually can outperform ABS I'd imagine even then, this only applied 20 years ago when ABS was still relatively primitive. I've had only triggered the ABS on my ~2015 car a couple of times but I don't think I could have done significantly better than it even in a non-panic situation.

serf 3y ago

>In this line of thought, it can be life saving to be overweight. I was about 120 kg back then and therefor had quite strong legs. people that lack the ability to lock the wheels on their vehicle on-demand shouldn't be driving it without aids. it's exclusionary, but even as a paralyzed person who is mandated to use hand controls for throttle and brake it was expected of me to demonstrate that I could leverage enough force on the brake pedal to initiate lock-up in a timely manner -- and modern cars with power-assist brakes should have little problem doing so.