The Story of Brakes
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- čas přidán 11. 09. 2022
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On Sep 23th, 2019, a new world record for 0-400-0 km/h was set at Råda airfield in Sweden by the Koenigsegg Regera . During this attempt, the Regera averaged around 1.1MW of dissipation during the braking phase, the system dissipated enough energy to power the average American home for just under 2 hrs. On almost every powered wheeled vehicle the brake system produces more deceleration force than the drivetrain’s acceleration force.
ORIGINS
The first wheeled vehicle brake systems consisted simply of a block of wood and a lever mechanism. To stop a vehicle, the lever was pulled, forcing the block of wood to grind against the steel rim of the wheel. Wooden brakes were commonly used on horse-drawn carriages and would even be used on early steam-powered cars that were effectively steam powered carriages.
DRUM BRAKES
The first brake system specifically designed for cars with pneumatic tires would be developed from an idea first devised by Gottlieb Daimler. Daimler’s system worked by wrapping a cable around a drum coupled to a car’s wheel. As the cable was tightened, the wheel would be slowed down by friction. While it was far more responsive than a wooden block, the exposed friction material of the external design made it less effective when exposed to the elements.
This idea evolved into the drum brake with a fixed plate and two friction shoes. These early systems used a mechanical cam that, when rotated, would apply a force through the web to the lining table and its friction material. On drum brakes, the shoe located towards the front of the vehicle is known as the primary shoe while the rearward one is designated the secondary shoe.
MASTER CYLINDER
At the drunk brake, a hydraulic cylinder containing two pistons replaces the cam mechanism, applying a force outwards on the brake shoes as pressure builds within the system. In hydraulic brake systems, a combination of rigid hydraulic lines made from either steel or a nickel-copper alloy and flexible reinforced rubber hoses are used to transfer fluid pressure between the master cylinder and the brake cylinders. Hydraulics also increased safety, through redundancy by allowing the brake system to be split into two independent circuits using tandem master cylinders. Four wheel-hydraulic brakes would first appear on a production car with the 1921 Duesenberg Model A though Rickenbacker would be the first manufacturer to offer them on vehicles that were mid-priced and more mass-appealing, in 1922. Shortly thereafter, other manufacturers would adopt hydraulic brakes and it quickly became the industry standard.
VACUUM BOOSTER
Many of these ideas involved using compressors to pressurize either air or hydraulic fluid and in order reduce the force needed by an operator to actuate a vehicle's brakes. First introduced by the Pierce-Arrow’s motor car company in 1928, this system, originally designed for aviation, uses the vacuum generated by an engine’s air aspiration to build a vacuum within a device known as a brake vacuum servo. By the 1930s, vacuum-assisted drum brakes began to grow in popularity.
DISC BRAKES
The next leap in braking technology got its start in England in the late 1890s with the development of a disc-type braking system by the Lanchester Motor Company. This system used a cable operated clamping device called a caliper that would grab a thin copper disc that was coupled to the wheel, in order to slow its rotation. By 1955, Citroën would introduce the Citroen DS, the first true mass-production car to field disc brakes. For the vast majority of modern disc-brakes systems, the disc or rotor is made from gray cast iron.
ABS
These systems attempt to modulate brake pressure to find the optimal amount of braking force the tires can dynamically handle, just as they begin to slip. In most situations, maximum braking force occurs when there is around 10-20% slippage between the braked tire’s rotational speed and its contact surface. By the early 1950’s the first widely used anti-skid braking system, called Maxaret, would be introduced by Dunlop.
It would take the integration of electronics into braking to make the concept viable for cars. As the wheel’s rotation starts to accelerate as it transitions out of braking the controller rapidly increases hydraulic pressure to the wheel once again until it sees the deceleration again.
COMPOSITES
Around the early 2000’s a derivative material known as carbon fiber-reinforced silicon carbide would start appearing in high end sports cars. Called carbon-ceramic brakes, they carry over most of the properties of carbon-carbon brakes while being both more dense and durable and they possess the key property of being effective even at the lower temperature of road car use.
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Keep growing up
Be positive that day will come
Sublime writing. So articulate & clear.
I love having you as a teacher...thank you.
Ui
@@shahbazstailan4361 iiu
I desperately want this style of video covering all the most mundane systems we've been taking for granted for over 100 years. Maybe even older stuff... Thank you so much for this content.
While his presenting style is very different from New Mind I can highly recommend Technology Connections if you're into nerding out over everything from type writers to coffee machines.
@@andersjjensen Yes. Technology Connections is good. Tech Moan is another good channel that is focused on old/obscure media formats and devices.
Technology connections is fantastic! I also enjoy veritasium, as well as techmoan.
Glad to see someone talk about some of the lesser discussed parts of a vehilce. Everyone is always going on about engines and power, but forget that good brakes really make the difference in a race, as well as on the street
Same thing as the tires, the only point of contact with the ground. They're the most common part of a vehicle that people are willing and even adamant about cheaping out on, but arguably the most important aspect about the performance and safety of a vehicle.
And suspension, it’s not only for comfort but also a part of handling.
"vehilce" Nice.
I agree, some of the coolest features on the car is the break/wheel combination.
Except most of what this guy said is wrong I have a bachelor's degree in automotive history... Disc brakes first showed their face in the 1930s... This guy's facts are all wrong.
I've been an automotive mechanic for over 30 years, I've repaired lots of brakes in my life. Still learned quite a few things from this video. Thanks
Repair as in change brakes? I've changed my brakes on an BMW E30 318i, and had the rotors turned as well
Repaired as probably repaired braking components.
Locked up calipers, hardware, rust buildup, fixing other people's mistakes....
@@pyropulseIXXI318i💀
@@christopherjohansson3073probably meant 328, typos are a thing uk
@@firmfire2385 E30 328i? Have you been smoking?
One thing to note is that the tire rubber compound improvements over time has also contributed heavily in to improvements in stopping distance
ABS, TC/SC have also DRASTICALLY helped tires last.
And does the suspensions too
Also the fact that they're not useing bicycle tyres anymore.
@@HARRYAZZHOLE I've never had to use ABS.... I've never been in a situation where I slammed on my brakes that activated ABS..... ABS isn't for making tires last. It is a pure safety feature, so people don't lose control in an emergency braking situation
@@pyropulseIXXI Not entirely true, ABS does make your tires last since it will prevent flatspotting your tire in those exact situations, but yes, in most cases ABS is not the cause for your tires lasting longer.
One omission maybe here, the Porsche's steel coating that basically makes rotor wear nonexistent. You change the discs when the coating is gone, just 50 microns or something similar. Engineering explained made a cool video about the technology that basically eliminates brake dust on ICE cars. But, as always, great quality content from you!
50 micron coating sounds like it shouldn't cost too much as far as materials, but it's Porsche so might not be cheap in practice
What's the point if you change the disc anyway? But instead of using a cheap disc you use an expensive one. Is brake dust so dangerous?
@@vsm1456 If not immediately scrubbed of in a wash, brake dust can aggressively etch into the wheel, which is undesirable if you have really nice wheels. It also looks gross. Not sure if it's worth increasing the cost of the brakes from hundreds to tens of thousands of dollars, but there you go.
@@vsm1456 Brake dust is actually very dangerous and has been linked to cancers and lung problems, etc.. But that's not really the point of their technology. It's more for vanity. Plus it lets them make money by changing your perfectly functional brakes early because "the coating is gone".
@@grekiki tungsten carbide, iys pretty tough stuff
I'm an ex-mechanic and found this a fantastically simple to understand, and yet properly detailed overview of braking systems. Well done!
My 2.0 litre hybrid Toyota Corolla estate returns 50 mpg on a run & even higher in nose to tail, stop/ start traffic. The worse the traffic, the better the fuel economy. Plus, if you stick it into sport mode it takes off like a scolded cat with a turbine like howl from the CVT box & electric motor.
But it's the regenerative braking that is totally new to me & I love feeling the energy flow around the car. The continuous dance between the ICE, the electric generator/motor and the battery is fascinating!
When I first got it I was driving like a bog standard ICE vehicle but after a while you get the hang of speed just being a temporary store of kinetic energy ready to be shoved back into the battery via the regenerative braking. Ready for immediate re-use if I floor it and the motor slurps it back out of the battery to aid the ICE.
Losses come from drag, friction, air-con and ancillaries.
It's an amazing system. I absolutely love it to bits & it's made driving interesting again after 42 years. I couldn't go back to a plain, non-hybrid. Nor could I go full EV yet as the infrastructure just isn't up to the job yet.
Thanks for a fascinating video. Yours is an excellent channel.
Left out is the story of air brakes. Invented by George Westinghouse, these were first used on railroad cars and locomotives. These were adapted for use on larger trucks and busses.
I live very close to a location where WABCO and Komatsu used to do a lot of the initial research of the air brake
During the first scene when the königsegg lined up, I could hear the top gear intro playing in my head.
I think it's safe to say that I have been conditioned.
Koenigsegg*
Some say he's still watching reruns on Dave, all we know is...
While examining a horse carriage at a museum I noticed the brake consisted of a piece of leather forced against the rim. The piece of leather was actually the sole of an old shoe. Hence the term “brake shoe”.
Would love to see a video on tires evolution. All, the rubber science is also amazing, now specially with silica added to substantially modify the rubber behavior in different occasions (frequencies)
Thanks for the topic. People always talk about improving the "go", and not about improving the "woah"
I've been a mechanic for 60 years and have repaired many brakes and still learned something from this video.
The fact that such an obscure topic not thought about is so interesting, shows that this channel is legit.
At my old R&D metallurgy lab, we were alloying & casting test samples for Mercedes-Benz for developing a patented pending idea called the "DRISK"... a combination of both the drum and disk rotor if you can imagine... never heard too much of what became of it later on.
Not sure what that is but it kind of reminds me of the UFO disk brakes Audi used on the original Audi V8. It was like an inside out setup. The rotor was retained on the outer perimeter, and the caliper was on the inside, allowing a larger diameter rotor in the same size wheel. Very innovative - but prone to warping because the drum portion was stamped steel if I recall.
Don't know what DRISK is but sounds similar to how some parking brakes works. Parking brake on the drum and normal brakes on the disk.
Merc has a disc brake on most models, with a small drum for the parking brake, at least until they started to use electric parking brakes (which typically use the disc brake caliper)
@@simonm1447 I assumed that wasn't what he was talking about since that 'drum in hat' hydraulic disk brake + integral cable operated drum parking brake is old as dirt. Though maybe @Loupy is also old as dirt? :)
I invented a "Y" disc brake many years ago. A normal ventilated rotor that flared to a 120 degree "V". So the caliper was mounted as now except the acted radially. So, you had one external pad in the "V" & TWO pads one each side on the outside of the "Y". So the pistons are radial acting against the curved pad in the "V" float would pull the floating caliper engaging the "outside the "Y" pads. Advantages you ca hope air channels from the front of the car through the body onto the flared Rotors & the back of the pistons to cool the fluid. The rotor is 3x wider on it's braking surface which is at it's largest diameter. The rotor can be half it's current thickness & 2/3 it's weight. Very quick & easy to change a pad set.
Disadvantages. Smaller rotor for same size wheel. The same or greater braking pad area. Similar but more effective percentage of rotor cover by pads.
I love how we took so many steps in braking-components to now be at a place, where we can even harvest that energy. I am excited for what that whole electric-motor trend will bring to this century-old problem.
Also, i really like these deep-dives. Is there anything regarding clutches in the pipeline? For some reason they still feel like magic to me in how they operate.
Braking please. Thank you.
Found my new favorite channel! I'm not the most knowledgeable person ever but I've definitely spent some time in, around and on car's trucks and heavy equipment. And within 2 minutes of watching this video I've learned more about the physics of braking energy than my 30+ years of driving experience taught me. I'm super looking forward to binge watching your videos.
Sublime writing. So articulate & clear.
I love having you as a teacher...thank you.
Have you heard any of Peter Rawlinson's (Lucid CEO's) tutorials on Utube. I'd glad pay hear/see him!
I absolutely lobe these videos about automotive systems and where they came from.
Excellent overview of the history of brakes. Single channel rear only ABS was common on pickup trucks for a while.
You have once again knocked it out of the park with this video. Simply amazing content my man!
Excellent video, all aspects of braking systems are explained, and the terminology of each component is spot on. Good job.
Very awesome video! And it was great to see someone mention the difference between race carbon brakes, and road carbon brakes. A lot of people tend to miss that bit of information. I only knew the difference to be honest because of keeping up with aerospace, racing and road technologies to the most detail I can get my eyes on....
Thank you for making this video! I have been working on my own cars for years and I guess I never stopped to think that there's such a long history of brakes. Most people just look at it as drum brakes vs disk brakes, and this video really explains all of the differences in lots of details, and the history, and also keeps everything simple enough that I can understand it even though I'm certainly no genius engineer!
"stopped to think"
Great video! I think this is the first comprehensive video I’ve seen on this critical system.
During the 1980’s, the transition from asbestos composite brake pad formulas to a less carcinogenic brake pad formulation using Kevlar was developed and patented by a man named Phillip Dougherty. This was the first effective attempt to get away from asbestos based brake pads. Ford motor company was the first to adopt this new technology and was quickly followed by other car manufacturers both in the US and Europe. Great video on a much overlooked topic!
Excellent job covering the history of braking technology development and the science behind each step of development. Can't wait to watch more of your videos. One early (sub) chapter of the story that I learned of recently... When the metal band around a drum was the default choice, Henry Ford chose to package that feature inside the transmission operating in an oil bath, and acting on the output shaft and thus stopping the driveshaft. It wasn't common on a car brand basis, but when Model Ts were half of the cars on the road in the 1920s, It sure was the brake system for a lot of cars! It did not have a lot of stopping power. Model Ts also had a lever and cable drum e--brake on each rear wheel. In 1928 Model As adopted four wheel drum brakes.
Thank you for making this truly comprehensive and excellent video about breaking systems.
There was also a pneumatic regenerative braking system wich worked by converting the kinectic energy into presure energy with a compressor and an air tank. It was developped in the 70’s
I am always impressed by the quality of your videos.
Another amazing video as usual!
I was just reading up on air brakes the other day (the Wikipedia page barely had content on it) and now there is this giant video on all sorts of brake technology !
A break is something that is broken. Do you mean "brakes"??
@@johncoops6897 lol yeah, I’ll fix it thanks; damn English damn it all to hell!
@@ericlotze7724 - LOL it is designed to trick the foreigners!!
This is a bautiful piece of work. Very educational format. Very clear and simple explanations. You know your stuff sir!
In my early vehicle builds in the 60's, (gravity powered gocarts when I was 5 years old)
my brake shoes were literally shoes. :D
amazing historical progression of a system as always. thank you
Amazing video taking us throughout the evolution of Braking system.
Much better and complete video than I expected. Educational quality here.
This channel makes brakes into movies.
Top quality video, much appreciated.
And as I changed the brake pads on my just the other day and spent a few minutes admiring the design of the sliding pin design - this video really hit the jackpot for me!
Perfect and full story. I learned a lot. Thank you
This channel is simply the best, it's absolutely 100% top notch stuff, and this guy deserves an award for making it so interesting and informative
Yet another well researched, informative and interesting video from New Mind.
Really very well explained and brilliant graphics. What a great informative video. Clear and concise speech, excellent job.
You failed to explain how air brakes work on larger commercial vehicles. They are not simply "pneumatically actuated". The brakes of a CDL level vehicle such as a Semi Tractor Trailer or large dump truck, etc: will have a very large and robust spring that is always applying the brakes and locking them and in order for you to be able to drive away from a parked position, you will have to build enough pressure (typically well over 100 psi), to overcome this large spring that is holding the brakes at each wheel. So the pneumatic system is actually RELEASING the brakes, which will then allow you to drive away. This is why you hear that large burst/ discharge of air when a semi driver applies the brakes-- because they are actually releasing air from the system, which drops the pressure and allows those springs to apply pressure to the brakes; again, the default state of commercial brakes while at rest is to be fully LOCKED. In this way, if there is every any issues with the brakes system failing or your compressor not working or you simply lose pressure through a leak, etc. - it will cause your brakes to lock by default, rather than having a run-away vehicle. You could probably talk about the history and design of commercial brakes as a standalone video.
I have always said that brakes are the most important part of any vehicle. And highly underrated.👍
Tires would be more important, as you can stop without brakes using engine braking.
Im amazed at how much of this i was completely unaware of. Thank you so very much!
Thank you for making this video learnt a lot
The Tesla at 25:07 has the hallmark “poor panel alignment”, at least they’re consistent!
I’m so glad he included regen breaking; great video.
As always an awesome video. Power is only good for straight lines. Brakes and suspension are what win races.
A positive effect brake technology regulations have had…
The iron composition of the rotors makes it easy to source proper and consistent alloy when doing a bit of mold making and casting.
It’s not too uncommon and there are a lot of folks out there who have been doing it for years in their backyard. Obviously takes a bit more complicated setup than a simple DIY garage set up to melt copper scrap or aluminum or what not…
But it’s fairly easy to get going and not nearly as complex or expensive as an industrial professional setups.
A lot of it can be had on the secondhand market because of all the foundries shutting down or it can be cobble together from parts for almost nothing. Then a few times a year when the buddies need things cast for antique restoration or whatever reason… Throw a hella party for an afternoon everybody brings over beer and sweats their ass off helping.
Quite a bit of prep work involved but it’s still a blast. There’s just some things that can be done easier and cheaper with a 3-D printer and simple moldmaking techniques instead of designing a cad model for CNC and trying to source proper materials. It has its niche but it’s also A lot of fun and sometimes you just need to part in cast-iron.
A lot of at home casters have always appreciated the consistency in the alloys of rotors. Able to be sourced at most scrap yards for less than $0.10 per pound. And gives you the benefit of picking matching sets from the same lot to be sure the alloys are the same.
I love content like this, history of practical technology, everybody is using, nobody know story.
I concur!
Very dedicated video. Great to see the history of brakes too.
Superb video mate. Thanks.
Nice Job 👌 thank you for spreading knowledge 👍
I'm very impressed with with research and detail given to the mechanics and design of things as menial as the caliper piston seals. That's dedication to quality information
Thank you this is amazing and very informative! Good work👍!
small note: porsche also fitted some cars with tungsten brakes which decreses brake wear drastically while improving brake power
I'm not sure if it's actually improving brake power. As discussed in the video, virtually every brake system exceeds the acceleration force of a car/vehicle. ABS is there to prevent wheel slip, which occurs when you apply too much braking force. In other words, if you can lock up your wheels, which you can, you cannot brake any 'faster', the limiting factor being what's actually touching the ground - tyres.
The problem is not the brake force but the tremendous amount of heat when braking from 300km/h or more. Also on the race track.
It’s called a thin layer of tungsten carbide. It’s to make the brakes last longer.
@@dudo626braking power is increased for sure. Obviously tires are the limiting factor, but you can also ways add stockier tires for allowing greater braking force. However even on the stock tires braking is improved at high speeds, as it reduces the velocity of the wheels quicker.
@@2seep Again, how can you "improve" breaking when brakes aren't the limiting factor?!? You *CANNOT* stop faster than traction will allow it without using other measures of breaking which isn't the topic here. "Reducing the velocity quicker" will literally block your wheels causing you to slip and lose traction. Please, tell me what drugs you are on, I want some too.
I've always wondered how brakes worked. Thanks for the video!
Super interesting video. Remarkable how all these big names (Daimler, Renault, Lockheed, Dunlop, etc) have been so important in this story.
I remember watching a video on the mechanism and development of drum brakes, if they hadn't been descended from carriage brakes I doubt they would even have been developed at all since disc brakes are one of the most straightforward brake designs possible.
You make an excellent point. One feature that prolonged the use of drum brakes was their self-energizing effect. Many car buyers disliked the over-assisted touchy response of power assisted drum brakes, and were content to stay with un-assisted drums long after they had accepted automatic transmissions and power steering. The linear response of disc brakes made power assist more necessary, but power assisted discs feel more progressive and controllable. Front disc / rear drum brakes were an imperfect compromise solution, but still an improvement in the evolution to power assisted, anti-lock four-wheel disc brakes that we are all accustomed to for decades now.
This was so relaxing and informative. I am into cars, but only informationally, because im not very mechanically adept. I just like to know how something works and how it came to be.
Thanks!
excellently explained and animated!
Very good video, thanks a lot for the work! Have a nice day
GREAT video, thank you!
Very high quality video.. It is much better than most of deticated automotive TouTube channels!
I learned a lot. Great video!
Really really good. Love all your videos. Thank you. 🖖
Scania for twenty some years include three types of branding I'm heavy trucks. First the engine slows with electric resisters. Then exhaust. Brakes. Finally, the latest electronic traction control friction brakes. The service intervals make maintenance servicing a quarterly effort. The trailers though have air brakes only.
Amazing content! Very informative
Unbelievably Amazing Content!
Thank you for the new video. You produce some good content.
Thank you for the information on brakes.
Nice work, awesome video!
Excellent coverage of brakes. The only system that I know of that was included in this story was the hydraulic retarders that are fitted to busses and coaches. (Essentially, a torque converter in reverse)
Great lecture. Thank you. You might want to add an addendum; Bosch is working on ‘brake-by-wire’ system which should improve the braking performance and the handling of the car under a heavy braking load.
can’t believe their inventions is still the parts that we use today. how smart is this people back in the day
I learned a ton! Thanks!
So little attention for such a crucial component usually. Thanks for the video
Masterful narration
Great work 😉
Well, this video stopped me dead in my tracks! Well done!
I just upgraded my 4Runners brakes to larger tundra brakes that fit and man what an insane difference a good set of brakes are on a vehicle. Especially a heavy SUV. stops on a dime now but also makes cornering and everything easier to control. A get set of brakes get you in tune with modulating the vehicle’s speed. Just makes the experience so much better.
Small world, I’m doing that exact same swap soon
Excellent video. Earned a subscription.
Great explanation 👌
You should do awd/ 4x4 next.. amazing videos as always
Excellent Montage.
In the 1980's Ford widely used a mechanical ABS system on the European Escort. In some countries only on the XR3 models but in others also on normal versions.
It consists of two belts (one on each driveshaft) which were connected to a flywheel type device which uses centrifugal force to detect rapid deceleration of the wheels and completely mechanically reduce brake pressure.
It was not a very effective system but it was a cheap solution for that time.
Amazing quality!
The history of brakes is a big subject to try and cover in such a short space but fair play to having a go. One minor point; the Dunlop Maxaret was used by Jensen in their FF model unveiled in 1966, although it was first featured in a CV8 FF 12 months previously.
Good job. Well done
Thank you for this
Excellent, thank you!
An acquaintance of mine started drinking brake fluid. He said he can stop at any time.
Wouldn’t mind doing that
What a wonderful video!
My grandfather used to call them ''Binders''
Two words: Nicely done.
Superb video!
This is an excellent video.
This video is a masterpiece!