The Story of Brakes

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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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[@NewMind]

▶ Visit brilliant.org/NewMind to get started learning STEM for free, and the first 200 people will get 20% off their annual premium subscription

[@shahbazstailan4361]

Keep growing up

[@shahbazstailan4361]

Be positive that day will come

[@trumanhw]

Sublime writing. So articulate & clear. I love having you as a teacher...thank you.

[@tomyanney5856]

Ui

[@tomyanney5856]

@@shahbazstailan4361 iiu

[@kenmeri5832]

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

[@jameswilson8907]

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.

[@iteerrex8166]

And suspension, it’s not only for comfort but also a part of handling.

[@cwtrain]

"vehilce" Nice.

[@RealEngineer]

I agree, some of the coolest features on the car is the break/wheel combination.

[@DesTries]

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.

[@AJ-ln4sm]

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

[@robertrocheville7769]

Repaired as probably repaired braking components. Locked up calipers, hardware, rust buildup, fixing other people's mistakes....

[@christopherjohansson3073]

@pyropulseIXXI318i💀

[@firmfire2385]

​@@christopherjohansson3073probably meant 328, typos are a thing uk

[@christopherjohansson3073]

​@@firmfire2385 E30 328i? Have you been smoking?

[@middleclassthrash]

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.

[@andersjjensen]

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.

[@jayschafer1760]

@@andersjjensen Yes. Technology Connections is good. Tech Moan is another good channel that is focused on old/obscure media formats and devices.

[@devonrosa4414]

Technology connections is fantastic! I also enjoy veritasium, as well as techmoan.

[@shadow7037932]

One thing to note is that the tire rubber compound improvements over time has also contributed heavily in to improvements in stopping distance

[@HARRYAZZHOLE]

ABS, TC/SC have also DRASTICALLY helped tires last.

[@Baba-yz3kp]

And does the suspensions too

[@Litl_Skitl]

Also the fact that they're not useing bicycle tyres anymore.

[@ExNought]

@pyropulse 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.

[@kevinburke6743]

@pyropulse ABS was designed to stop a wheel/s locking up! Doesn't work in F1. Are you sure you know when ABS kicks in? If you come up to long bend & take fast. Mid bend just let go of the steering & press the break pedal as if you mean slow down to a normal stop. No an emergency stop. Then tell you have never experienced ABS. ABS in not just a braking feature, its also a suspension, dynamic control feature. It is not braking feature at all really. It releases then reapplies the brakes in rapid succession(Kepler's Theory of braking.) overall with EBD it makes the braking effort proportionally evenly distributed by the load, vector, rotational speed of each wheel. Locked wheels burn flats on tyres!

[@philking7805]

I'm an ex-mechanic and found this a fantastically simple to understand, and yet properly detailed overview of braking systems. Well done!

[@Aengus42]

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.

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!

[@grekiki]

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

[@vsm1456]

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?

[@Hawk7886]

@@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.

[@calholli]

@@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".

[@chimpinainteasy819]

@@grekiki tungsten carbide, iys pretty tough stuff

[@demal1010]

Thanks for the topic. People always talk about improving the "go", and not about improving the "woah"

[@rayfridley6649]

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.

[@jordanchamberlain4377]

I live very close to a location where WABCO and Komatsu used to do a lot of the initial research of the air brake

[@calholli]

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.

[@NomenNescio99]

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.

[@konigsegg_1to1]

Koenigsegg*

[@exafrost]

Some say he's still watching reruns on Dave, all we know is...

[@_Solaris]

The fact that such an obscure topic not thought about is so interesting, shows that this channel is legit.

[@TelmoMonteiro]

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)

[@0neIntangible]

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.

[@bradley3549]

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.

[@NearCry91]

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.

[@simonm1447]

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)

[@bradley3549]

@@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? :)

[@kevinburke6743]

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.

[@realmichaeltian]

One of my favorite feelings (now that I’m thinking about it) is the feeling of bouncing on the edge of locking/abs when braking hard in the snow ❄️😌

[@grosfdp3654]

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

[@gianni_schicchi]

From now one I will convert all thermal information to number of full size iPhone’s worth of battery charges.

[@wrxgeneration]

I've been a mechanic for 60 years and have repaired many brakes and still learned something from this video.

[@elevatedascent]

I absolutely lobe these videos about automotive systems and where they came from.

[@PiTdeLyX]

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.

[@BariumCobaltNitrog3n]

Braking please. Thank you.

[@Kyntteri]

An acquaintance of mine started drinking brake fluid. He said he can stop at any time.

[@delquandrecolter3477]

Wouldn’t mind doing that

[@_Pyroon_]

I never realized that so many automotive developments were downstream from aviation.

[@ryancraig2795]

Excellent overview of the history of brakes. Single channel rear only ABS was common on pickup trucks for a while.

[@theobserver9131]

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

[@red_eye_diy]

The Tesla at 25:07 has the hallmark “poor panel alignment”, at least they’re consistent!

[@tripwire441]

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!

[@IceColdProfessional]

This channel makes brakes into movies.

[@markhonea2461]

I have always said that brakes are the most important part of any vehicle. And highly underrated.👍

[@2seep]

Tires would be more important, as you can stop without brakes using engine braking.

[@xXRedTheDragonXx]

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!

[@9HighFlyer9]

"stopped to think"

[@NomenNescio99]

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!

[@trumanhw]

Sublime writing. So articulate & clear. I love having you as a teacher...thank you.

[@kevinburke6743]

Have you heard any of Peter Rawlinson's (Lucid CEO's) tutorials on Utube. I'd glad pay hear/see him!

[@trumanhw]

@@kevinburke6743 Thank you. I'll check that out!!

[@monbulla4026]

small note: porsche also fitted some cars with tungsten brakes which decreses brake wear drastically while improving brake power

[@dudo626]

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.

[@no-damn-alias]

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.

[@2seep]

It’s called a thin layer of tungsten carbide. It’s to make the brakes last longer.

[@2seep]

@@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.

[@dudo626]

@@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.

[@Carstuff111]

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....

[@jvogler_art4708]

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.

[@NewMind]

Small world, I’m doing that exact same swap soon

[@hullinstruments]

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.

[@dgrn101]

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.

[@m_sedziwoj]

I love content like this, history of practical technology, everybody is using, nobody know story.

[@joshgreen2164]

I concur!

[@garethbaus5471]

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.

[@billyjoejimbob56]

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.

[@markrowland1366]

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.

[@stephenbrookes7268]

This is a bautiful piece of work. Very educational format. Very clear and simple explanations. You know your stuff sir!

[@MrEazyE357]

You have once again knocked it out of the park with this video. Simply amazing content my man!

[@chrislaing7153]

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)

[@crim7ind]

As always an awesome video. Power is only good for straight lines. Brakes and suspension are what win races.

[@MrZenzio]

I am always impressed by the quality of your videos.

[@Sunburnae92]

can’t believe their inventions is still the parts that we use today. how smart is this people back in the day

[@VincentNacon]

Great video! I'm really glad you actually covered the EV's braking system too!

[@codymoncrief8478]

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

[@__Razer]

12:40 Woah WOAH, why did you just skip over the advances made during wartime? That's a lot of time for a lot of advances to braking technology.

[@steveskouson9620]

The inboard disc brake system on the Jaguar, is also designed so that a car can be put over a grease pit, and change pads without jacking, or removing the wheels. That is for endurance racing. Driver parks over the pit, a mechanic changes out the pads, in a very few minutes. steve

[@Romuls753]

For those that may doubt the figure that the braking system on a vehicle produces more energy than the acceleration system, a Detroit DD15, on average, produces 455 horsepower and the engine brake alone on high produces ~600 horsepower of braking force. I'm a truck driver, I have years of experience with the DD15, and I would be practically thrown to the windshield if I was in an emergency stop with the engine brake on high when lightly loaded. It is my habit to throw the engine brake on high during an emergency stop and use the service (air) brakes to further slow down, and if needed I'll try to take another lane IF: 1. another lane is open, 2. There isn't a vehicle that would cause an accident during lane change or a rear end accident

[@ericlotze7724]

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 !

[@johncoops6897]

A break is something that is broken. Do you mean "brakes"??

[@ericlotze7724]

@@johncoops6897 lol yeah, I’ll fix it thanks; damn English damn it all to hell!

[@johncoops6897]

@@ericlotze7724 - LOL it is designed to trick the foreigners!!

[@justmike2944]

My grandfather used to call them ''Binders''

[@sebastianberger6890]

There is an error at 20:20 There is no hydraulic accumulator in an standard ABS Block. The excess pressure gets pumped back in the supply line leading back to the master cylinder. That's why you feel the brake pedal pulsating during ABS operation. A hydraulic accumulator is only needed for an electric brake booster. Nice video! Love brakes.

[@FoxMacLeod2501]

Small thing, I know, but brake drums and rotors are typically cast iron. Unrelated, but to help understand hydraulic systems, I find it helpful to think of brake hydraulic cylinder size ratios (such as described at 7:00) as similar to either a lever with one end longer than the other - like you mentioned - or like the easily-seen gears and ratios on a bicycle. Longer, easier distance traveled by the force of my leg on the bike or brake pedal, put into a smaller gear or piston, converted by the diameter difference into a shorter distance of movement, with a much stronger push than I put in on the other end - and of course the inverse is true too. Hope this helps someone wrap their mind around hydraulics.

[@calholli]

Yes, and it's directly proportional; so if your foot on the pedal is traveling 3" and the brake piston is traveling 1"-- that is 3x the distance, and will result in 3x the force at pads.

[@DROGOC0P]

I think of it simply as smaller area = less force applied, longer distance traveled for same volume displacement. therefore, higher area piston, same volume displaced, much less distance traveled but greater force due to higher area

[@edh2246]

No mention of the Ford Model T brakes. Brakes are a single band, originally with wood lining, that squeeze a single drum within the transmission which is bathed in motor oil. Later years used woven cotton material for lining. This system put braking pressure on the driveline. No brakes on the front wheels.

[@realmichaeltian]

The amount of time and thought that has gone into brakes is mind blowing

[@Assimilator1]

Cool video, as a car mechanic myself for 27yrs I found the history particularly interesting. One correction though, you say the automatic adjusters eliminate the need for adjustment on drum brakes at 09:58 , this isn't quite the case. Whilst it certainly reduces the need, the drums still need to be removed periodically to remove the dust and manually adjust the adjusters up (typically 2-3 yrs, about 20-40k miles), if this isn't done the pedal travel will gradually get longer and longer, as well as handbrake travel. Also the shoes will wear abnormally with greater wear occurring nearer to the wheel cylinders pistons.

[@kevin9c1]

Nice. One correction which isn't relevant to brakes: TPMS has been around since the late 80s in some Corvettes.

[@zvisger]

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

[@tbas8741]

Electric Brake motors are also how Tenpin Bowling Setting Tables or Pin tables(which are the large "trays" that hold the pins & place them) Are slowed down to a smooth slow speed when placing Pins so they don't wobble and fall over, while releasing them very quickly (with big long "Belts" which are really just big rubber ropes heat welded together, which often fail and table might fall or get stuck uptop, but often not in some in between position as the Brake Motors are the only thing holding them up when in transit so if they fail or belt snaps tables drop with a large force as they can weigh well over 150kg. These "brake motors" work on same principle as Regen Braking in EV's, althought they don't harness the energy generated but instead dump in into giant Resistors banks with capacitors they just let the produce energy dissipate as heat and other losses. Tenpin Bowling Pin tables have used these electric motors for near 100 years if not more, (- Former Pinsetter Mechanic)

[@Mik1604]

Super interesting video. Remarkable how all these big names (Daimler, Renault, Lockheed, Dunlop, etc) have been so important in this story.

[@glenwoodriverresidentsgrou136]

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”.

[@def6849]

Outstanding, excellent content. Really enjoy the mix of history and technical explanation.

[@BBT609]

Absestos was the infamous material used for braking cause it was able to resist heat so well. The problem was that people were getting sick because of the dust it created and when breathed in, it would attach itself to the inner lining of the lungs, causing breathing problems and form tumors, causing what we know as mesothelioma. We start to see the increase of semi metallic and ceramic brakes once asbestos, a world wide insulating material was being banned.

[@allanashok]

Me clicking on the video like, "no way its a half an hour video about brakes" Also me watching the whole thing with full interest!

[@error200http]

1:47 Thanks for showing Warsaw, Poland. Film was taken near Politechnika metro station.

[@theanimeotaku2794]

ABS is great an all for rain and regular asphalt decreasing braking distance but when it comes to snow/ice surfaces it's terrible even at low speeds as I found

[@abdulabdanahib9617]

because of such high-quality videos, I started learning English

[@andrefiset3569]

Montreal subway like the one in Paris use wood brake pads impregnated with peanut oil and salt. It is silent don't damage the steel wheels and smells funny after emergency braking.

[@tba3900]

No mention of Telmar, a iron disc bolted to the tailshaft and by applying an electrical current through copper windings around a stator it creates a magnetic field on the disc slowing the vehicle down magnetically.

[@krrishmaheshwari4860]

Amazing video taking us throughout the evolution of Braking system.

[@exafrost]

Well, this video stopped me dead in my tracks! Well done!

[@rairaur2234]

This video is simply superb. Thank you

[@233kosta]

The only real issue with regenerative braking as concerns regular brakes is the rust that builds on the discs when they're not in use. Solution is dead simple though - add a touch of hydraulic brake at least once for every journey. Better yet - programme that into the system.

[@aprilkolwey4779]

This is one of those things that probably varies a bit depending on the car, but the one I have (2013 Toyota Prius, a hybrid) does this - it prefers mostly regen most of the time, but once you get below 10km/h the friction brakes are engaged for the final stop. It will of course do so sooner if you request it to slow faster than the regen can handle.

[@233kosta]

@@aprilkolwey4779 Seems a good implementation. I think some Teslas are programmed to just not use friction brakes at all unless you use the brake pedal

[@aprilkolwey4779]

@@233kosta This is with the brake pedal being pressed - this car doesn't apply significant regen when the pedal isn't pressed. It's a brake-by-wire system, so even though the pedal feels "normal" when pressed, it's not actually doing anything unless you max out the regen, go below 10km/h, or a few other cases.

[@233kosta]

@@aprilkolwey4779 Yeh, makes sense, the single pedal thing is relatively new

[@simonm1447]

The Etron does this automatically, tom prevent rust buildup.

[@Lenoch_]

DO TRANSMISSIONS! There’s so much to learn, like: why did it take so long for the first front-wheel drive car to be developed (versus when cars were first invented), the development of dual-clutch transmissions and much much more!

[@Mastermind12358]

Actually, in many circumstances (if not in all) such as on Ice or snow ABS does not shorten the breaking distance, it actually lengthens it. But the driver has added stability (especially if its a less experience driver that does not realize that you cant turn the car with locked wheels)

[@SRQmoviemaker]

I work on cars for a living and this will be a video I make my apprentices watch [I have a playlist like 2 hours long about automotive history/ stuff like this]

[@G5Hohn]

The rotating cam drum brake is STILL the standard brake arrangement for large class 8 tractor trailers.

[@thebamplayer]

Before the invention of brakes: How we used walls, to decelerate.

[@WoLpH]

No, we used feet. Have you never watched the flintstones?

[@dekutree64]

Back then it was called breaking.

[@laha1959]

I might be wrong but I dont think that average american home consumes 1.1MW of power in two hours, a month could be a more accurate guess

[@Travis0palzae]

MW is the power. MWh is the energy. So 1.1MW*8s is around 2.4 kWh which is 2 hours of usage for a 30kWh per day house.

[@WoLpH]

The standard for American homes is a 200A breaker at 240V which allows for a maximum power consumption of 48kWh. That means we can reach 1.1MW in 23 hours :)

[@MarksTournaments]

@@WoLpH American homes are 120v

[@WoLpH]

@@MarksTournaments They're officially 240v split phase :) The outlets generally only get 1 of the 2 parts of the split phase which makes 120v. Your AC most likely runs on 240v by using both parts of the split phase.

[@quantumleap359]

Excellent video, all aspects of braking systems are explained, and the terminology of each component is spot on. Good job.

[@Mishn0]

Check your data on the Benz Patent-Motorwagen. It had solid tires. The development of pneumatic tires was driven by the bicycle, not the motor car. Also, even though this was mostly an automobile based presentation, it would have been interesting to include the brakes used on modern diesel/electric locomotives. They use the motors as brakes during deceleration but it's not captured regeneratively. It's just converted to heat by a giant resistor on top of the locomotive. Locomotives don't have the batteries to take advantage of regeneration and the high current from the braking would blow them up anyway.

[@torkeautomotive]

Much better and complete video than I expected. Educational quality here.

[@Afuru1]

A return spring was an incredible invention.

[@billyjoejimbob56]

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.

[@pushing2throttles]

On God. On my mama! On the southside 09, on hood, New Mind is one of KZbin's most important channels and content creators.

[@johncoops6897]

13:25 - the advantage of disc brakes is just about cooling! It's about the fact that metals get larger when they get hot. With a (internal) drum brake, the hotter it gets, the larger that the drum becomes. This means more pedal pressure/movement is required to push the brake shoes out farther to accommodate that larger diameter drum. The larger the drum, the more pronounced the "pedal dropping" effect, and sometimes requiring that the brakes were "pumped" to get a new bite. The more pressure and heat applied, the hotter the drum got and air cooling was minimal. With disc brakes, the disk becomes slightly thicker when it gets hot, so the pedal remains high throughout the braking process. A solid disc rotor doesn't really stay cool very well, however the more modern "ventilated disks" use centrifugal force to suck air through the rotor to cool it.

[@djjudas21]

I’m so obsessed with brakes that this appeared in my feed. Meh, I can stop whenever I want.

[@gxlbiscuit]

I’m so glad he included regen breaking; great video.

[@brucemclaren-]

"The safety of steel from pedal to wheel" - Henry Ford advertising his push rod brakes😂😂😂

[@Conservator.]

Thank you for making this truly comprehensive and excellent video about breaking systems.

[@TCPUDPATM]

Great video! I think this is the first comprehensive video I’ve seen on this critical system.

[@mhfs61]

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.

[@paulspaws1521]

Aww I was hoping to learn more about the regen braking of hybrids.. :(

[@mrdainase]

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.

[@Simon-nw9bf]

I'm here watching this marvelling at how simple and efficient a machine the bicycle is. A cable through a tube connected to some rubber pads. When it loses grip you wipe the rims with Windex and tighten the clamps with an Allen key 😆

[@Yosh1az]

drum brakes are pain in the ass to disassemble and assemble those tiny strong ass springs are so strong to strech

[@meeder78]

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.

[@Kj16V]

Here's a (slightly) interesting fact. ABS is actually German, meaning "Antiblockiersystem." The English phrase: "Anti Lock Braking" is just a nicely fitting backronym!