Finally a gearbox that doesn't need springs or elastic bands

@voxelfusion9894

3 жыл бұрын

Aren't the springs just inside the clutch? That does make it really compact.

@JSFofWT

3 жыл бұрын

@@voxelfusion9894 its just a friction type clutch

@Positroni

3 жыл бұрын

@@JSFofWT I presume you know the insides of that clutch, is there a image of the inside somewhere on the internet? If not, is it some type of compliant centrifugal clutch?

@JSFofWT

3 жыл бұрын

@@Positroni no it's just a bushing held in place with friction

@user-zi8jn1go8k

3 жыл бұрын

@@JSFofWT well, bushing is kind of like a rubber band in this case

I’m simply amazed at what can be built using LEGO and also so impressed with the way an engineer’s mind works! This is very cool.

@LucasDynamics

Жыл бұрын

I have build a even smaller automatic gearbox if you want you can check it out on my channel...

@kaseycrooks5080

8 ай бұрын

Engineering is the best job on earth.

@LegoTechnicMan

5 ай бұрын

​@@kaseycrooks5080yes

i am speechless about this auto-gearbox its... unbelivable simple

2:28 you broke my mind because its so ingenious but so simple. awesome concept!

@polbecca

2 жыл бұрын

Multiple differentials with power added in here and there are also the basis of tank transmissions. You don't want to put a brake on one part to make another part go faster, e.g. for steering, because that's wasteful of power, so instead you can use another diff as an input to vary things.

@LucasDynamics

Жыл бұрын

I have build a even smaller automatic gearbox if you want you can check it out on my channel...

This is way better than the idea I came up with as a kid. Mine shifted from 3:1 up to 1:3 via a centrifugal governor and just ground the gears until it built up the speed to shift. Seems to me I messed around with differentials too but that first one stick in my mind because I remember that once it got going it could actually outrun me. Good times.

GREAT explaining. I really learned something today. Never thought this would interest me, but it was soo captivating!

@ferdoreznik

3 жыл бұрын

Thank you :)

Finally a video as simple and educational as the old chevrolet videos

Very simple and functional.

Thanks for the detailed breakdown. One question, since the slipping gear is always slipping, do you sacrifice a lot of engine power?

@ferdoreznik

3 жыл бұрын

It is slipping only when there is high load on the output. Of course there is some energy loss. Maybe thanks to big ratio difference between two speeds the lost energy in friction clutch is still not so big to stop the car.

@Xayuap

3 жыл бұрын

nice job, could be done with planetary gears

@maebae5350

2 жыл бұрын

There are similar-funtioning parts in some cars that do that called torque converters. There was an old car made in the 50s that had no gears and only used the torque converter which would keep slipping up until max speed. That car was infamous for being horrendously bad on gas mileage, down to only 5mpg or something. A big use for them is in drag racing where they'll rev the engine up to optimal torque/horsepower while the car remains stationary and when they launch that torque converter prevents the engine from detonating the transmission, and this is done to maximize launch potential. Bad for gas mileage but those types of cars aren't meant to be efficient, just fun lol

@Xayuap

2 жыл бұрын

@@maebae5350 hydrodinamics ones, ¿right?

@ConnorSmith-lh7uw

2 жыл бұрын

@@tomstech4390 Still better than anything I could come up with

I am impressed. Thanks for sharing this amazing automatic transmission idea. I will definitely use this design and will pray for you when having fun. Awesome :)

Well done. I thought of something similar decades ago, but the Lego parts I needed to build it didn't exist yet; by the time the parts I needed did exist, I had moved on to other hobbies. Nowadays I wrench on purpose-built RC cars with tiny engines.

That amazing explanation of transmission system Hats of you 👍👍👍🙏

I imagine there's a range where the resisting torque on the output is high enough to cause the clutch to slip, but low enough that it allows the clutch gear to still rotate, effectively giving a range of variance in the output ratios. I think that this may actually be a CVT

@podulox

2 жыл бұрын

I think so :) Although it has two distinct ratios at each 'end', the 'middle bit' has some variability... So it's a 2-speed gearbox with a smooth transition between ratios. Good call, well spotted :)

@robinpage2730

2 жыл бұрын

Replace the friction clutch with a magnetic clutch, and you could sell this in regular cars as a sealed CVT

@adamkovarcik914

Ай бұрын

Sadly this transmission doesnt work. You can get the same result using only the slip gear

Thats a beautiful and smart creation

Excellent, best video explaining a Lego auto transmission.

@ferdoreznik

3 жыл бұрын

Thank you Kenneth 😀 !

this looked like a video were a well known design was claimed to be revolutionary, but this was actually really well made, and well explained, this video actually wowed me.

@tazargroups.r.o.2152

2 жыл бұрын

Thank you :). Incredibe things are possible to be made of lego.

Very well explained!

Final a great design with even a greater explanation

Lego has come a long way since I was a kid.

That's just awesome! So simple yet so ingenious. Should put one of these on an input shaft, speed it up or slow it down with gearing, then put another one. Should be able to get 3-4 speeds out of it with with different torque thresholds.

Really clever! Nice and compact, simple, efficient. You can put more than one in a row as well.

I like how you repurposed a differential to use as a transmission! Very cool outside the box thinking!

@ferdoreznik

2 жыл бұрын

Thank you Josiah...

Awesome videos, thank you so much for share.

This could be an excellent concept for a practical CVT in a car if: 1) a hydraulic torque converter is used instead of a clutch, and 2) a reverse gear is included.

I see you've experimented with big trends in the past, but please stick with lego engineering videos! If they are as good as this, I'm sure your channel can grow.

It is not only using 1:1 and 2,33:1 speed ratio but a large fork between both (we can see in a slomo white geer turning sometime). Very clever and compact. I cannot wait to see it on a train. Thank you for sharing.

@42Goopy42

3 жыл бұрын

It is also not actually 2.33 to begin with. Gear ratios when it comes to transmissions are a ratio of input/output. 2.33 would actually be a slower gear. Look up ratios of a manual transmission found in a car or truck (or even an automatic) and see how 1st gear is usally 3.xx or 2.xx or similiar.

Really cool concept and it seems to also have a small cvt component. However, transmission ratios are input divided by output. 2.33 would describe a gear requiring 2.33 input rotations for 1 output rotation. Likely just done backwards but in the automotive and industrial world its backwards which leads to a little confusion. Awesome concept and it would be cool to see more gears added in this way.

Now this is brilliant!

Excellent video with a great explanation and demonstration of how it works!

@LucasDynamics

Жыл бұрын

I have build a even smaller automatic gearbox if you want you can check it out on my channel...

Simple, but does the job perfectly

@LucasDynamics

Жыл бұрын

I have build a even smaller automatic gearbox if you want you can check it out on my channel...

Freaking awesome 😲👌🏼

Thanks for this idea in the moment i am building a crawler and this video hleps👍🏽

Genius, SUPER GENIUS, greetings from Lima Peru

I am so excited i saw diffential drive shaft in my lego insruction ,thats why i did test run

This is a fantastic idea! It would be rad if they made a small self contained torque converter with a stator. It would be insane torque multiplication.

Beautiful job. God bless you.

Very good explanation!

Such a simple mechanism and better than every other automatic gearbox I've seen made with Lego. And you know what the best part is? Every other solution I've seen involves gears grinding at least some of the time, this *JUST* works.

@ferdoreznik

2 жыл бұрын

Thank you Tangent. Exactly this was my intention. Make something absolutely simple and working. Funny thing is, that many people dont believe that it really works... they thing that the car can pass the obstackles even on high speed and switching down is just illusion.. Because of them I made another video showing how it works. I made simple switch which disables friction clutch to show how the gearbox works only on high speed. Here. m.kzread.info/dash/bejne/g3aHk7qcg9rRj8o.html

Awesome thanks for the Auto Transmission

This is incredible!!!

Very usefull! Thank you!

This is fantastic! Great video!

@LucasDynamics

Жыл бұрын

I have build a even smaller automatic gearbox if you want you can check it out on my channel...

Very cool idea. I just wonder if that is kind of a magical illusion that looks right, but it works only because the car would also successfully climb the hill also without the transmission. Isn't there simply the extra force coming from the higher gear ratio "destroyed" by the friction in the clutch?

@ferdoreznik

3 жыл бұрын

Hi Tobias, I have to say that this is very good question, I spent so many hours by tuning this transmission up that I even did not tried it. But I still have the car built so I just tried to climb some obstacles like small stairs (like 3-5cm tall), even climbing the car to vertical wall. Then I changed the friction clutch gear with a normal gear and the car was not able to pass some obstacles. The motor just stopped. So it really works well. Try to build it.

@t_munz

3 жыл бұрын

@@ferdoreznik Thanks for your answer, so all I have to say: well done ;-)

@m.sierra5258

3 жыл бұрын

My first thought was also that instead of actually switching gears it just slows down and the rest of the energy gets lost to the slip gear. But if you say it works then it might be interesting to do the physics calculations behind it. The biggest problem is that there is nothing really to hold the slip gear, so if there is enough resistance at the wheels it should just backdrive. While it wouldn't be perfectly efficient, the efficiency could definitely be increased by lowering the slip gear friction and adding a backdrive prevention mechanism.

@konstantinkh

3 жыл бұрын

You definitely lose some of the motor power to the clutch gear. Can't avoid that with this kind of setup, which is why you won't see this exact setup on cars. (Something similar is used to switch gears in automatic gearbox, though.) But we care about output torque here, not the efficiency of power use. This setup won't produce as much torque at the same speed as a fixed gear would have, but it's still way more torque than you were getting out of high gear ratio setup, so it still works.

@frosttgasian1168

3 жыл бұрын

I’d imagine torque would be multiplied for the lower gear. If you think about it, the high gear is overdrive and when the clutch slips the ratio drops to 1:1, increasing the torque

It is fascinating, what everything is possible to make from Lego... 👍👍

this video is brilliant

i rewatched this several times. It’s genius.

@ferdoreznik

2 жыл бұрын

Thanks. 🙂

Really nice man good job

отличная идея! будем использовать )

So genius in its simplicity.

Very simple but awesome solution to a big question.

@LucasDynamics

Жыл бұрын

I have build a even smaller automatic gearbox if you want you can check it out on my channel...

Brilliant!

thank you for explaining nice vid

Very impressive. You could add something like a rachet to stop feedback under heavy load. Although I barely saw that happen in the testing you showed.

A more complicated version of just using the slip clutch alone, awesome.

This is the basic principle of the Voith DIWA automatic gearboxes mainly used in city buses. While stationary and at the beginning of acceleration, the engine's torque is fully transferred through the (internal, it's not seperate as with most gearboxes) torque converter and the lower the speed difference between engine and gearbox output the more this shifts towards the parallely operating fully mechanical 1st gear. At a certain speed difference the torque converter will then become almost completely needless and the fully mechanic 2nd gear is engaged. With this gearbox type, the torque converter is only functional in 1st gear and is disabled from 2nd (of the 2, 3 or 4 gears) onwards, but is used as a retarder, just to have mentioned this.

Such a good idea

Thats so cool Great job man

I have been looking for this so long

In particular range of load it behaves like gearbox. However, under the very high load: engine works, vehicle stops and clutch slips different direction. I like the solution with the clutch/friction, as it enables smooth rotation speed change depending on load. It's great! Nevertheless, I prefer the friction between "gears" (like in planetary gear), when the minimal speed (the first gear) is limited by the engine power, not by gear clutch. Regards

This is a super cool design and is actually a fairly similar idea the Toyota Hybrid system uses (except obviously much more complex, being motor-generators rather than gearboxes and they can adjust to act like a CVT instead of a 2-speed gearbox)

Extraordinary !

@tazargroups.r.o.2152

2 жыл бұрын

Thank you 😃

It's compact and it looks to be efficient too! Very good job !👍🙂

@LucasDynamics

Жыл бұрын

I have build a even smaller automatic gearbox if you want you can check it out on my channel...

that's a really cool little device, might have to build one now

Very good

Amazing!

Thank you for explaining and not just showing it.

@LucasDynamics

Жыл бұрын

I have build a even smaller automatic gearbox if you want you can check it out on my channel...

Very clever.

I never realized what the white gear was for until now

From one frontier its a true automatic gearbox, but the target of gearbox is with decreasing rotation speed increase strong of rotation. The white gear is getting part of the rotation moment. That means, that you simply decreasing rotation speed, without chanching rotation strong. P. S. sorry for my english and commas. I am from Russia

Fantastic construction - and very well explained... thank you! 😀👍

@LucasDynamics

Жыл бұрын

I have build a even smaller automatic gearbox if you want you can check it out on my channel...

AWESOME!!!

Yes this is the right approach when you try to use a differential like a gear box, (in the lego world)

Some seriously clever engineering here for a fun Lego project!

@LucasDynamics

Жыл бұрын

I have build a even smaller automatic gearbox if you want you can check it out on my channel...

That is the Best gearbeitet ever made

Best innovation you can change the world good luck

@ferdoreznik

3 жыл бұрын

Thanks 🙂

Brilliant

You are basically doing what Toyota is doing in their CVT cars. They use a planetary gear with 1 output free spinning until you want to accelerate. At the point you want to accelerate they apply a force to the free spinning gears causing the energy to redirect into the wheels. Now you could use a clutch for this but Toyota was like nah lets use an electric generator motor for that. So they take away energy from the gears which is used to power the electric motor. (And stuff like the AC.) Since a planetary gear is solid metal the transmission basically never has to be replaced. And since they don't use a clutch the amount of force is never really that big. You can activate reverse while still driving forwards and nothing will break.

Great idea! However I found that using two motors instead of the clutch works better. I used a non Lego product called Sbrick in order to shift manually via bluetooth. Using different gear ratios helped my vehicle pick up speed but still have the power to take off from a start.

Good job

I really appreciated the simplicity of the solution, much better than other solutions that require more pieces. I have actually applied your solution to one of my MOCs, my red station wagon, which is equipped with two L motors. But unfortunately the friction clutches (one for each motor) spin the opposite direction it should when stressed, probably due to the MOC's weight (850g)... I believe in my case each motor should get two friction clutches, but there's no room for this upgrade. Anyways, just sharing the experience, I'll apply it to a lighter model instead. Cheers!

@LucasDynamics

Жыл бұрын

I have build a even smaller automatic gearbox if you want you can check it out on my channel...

Thanks!!!!!! Now i can make an offroader that won't constantly go slow

Nagyon jó ötlet!

Theoretically, could you stack 2 of these for a wider range of speed? I'm assuming it would become slower but stronger

@yeetmanishere

7 ай бұрын

Cvt with legos

@iacopotuttino5515

5 ай бұрын

Technically yes

1:35 Minor correction: even when one of the outputs of an open differential is stationary, it still splits *torque* evenly. It's the power that goes to the other output.

@ferdoreznik

3 жыл бұрын

Yes you are right in splits the power 50:50 all the time. But the rotation goes to one output only. that is important to understand that you can even combine inputs, not only split.

For a basic automatic transmission made from lego, it is wonderful. I'm a little surprised that the lego makers didnt come up with it. Ir they haven't taken your idea and used it

@LucasDynamics

Жыл бұрын

I have build a even smaller automatic gearbox if you want you can check it out on my channel...

Thanks for this cool video and the time you spent on explaining. Question: Does/ doesn't the friction gear wear out quickly in this construction?

@ferdoreznik

3 жыл бұрын

There are iron plates pushing on plastic, I thin it will last some days, but of course it is just a toy. Important for me was to demonstrate that this way can work.

@Bassotronics

2 жыл бұрын

Good if replaced for a fluid clutch aka torque converter.

@CrusaderSports250

2 жыл бұрын

@@Bassotronics unfortunately Lego doesn't do one.☺.

@Bassotronics

2 жыл бұрын

@@CrusaderSports250 I made one one time with model team hubs and fan blades inside. It was filled with low viscosity corn syrup. Lol I was 16 and a lil whack with inventions.

Nice explanation :)

*”Let me explain you”* So cute 😄

My friend made one of these when we were kids. He chained 3 together in series to have more gear ratios.

Brilliant,

Nice 👍

Freaking Legend. Totally going to build this going forward. Much Appreciated.

@LucasDynamics

Жыл бұрын

I have build a even smaller automatic gearbox if you want you can check it out on my channel...

normally i would think of "auto transmission" as say first gear max is 60 mph, when i get to 60 mph the gearbox would automaticly switch to second gear, etc etc till last gear. but this is a good enough model :D good job!

Thanks

it really work!

Nice idea :)

this must be one of the best gearboxes ive seen on YT

This obviously works, nice gearing, but my understanding from tests and logic says: *there cannot be two fixed gear ratios in one closed gear system* So if it slips, every rotation of the output axle is possible. Obviously this burns some energy as it doesn't use torque to shift, but force x rotation = power. But your great accomplisment: You modelled a local (higher) output torque maximum into the slip range. However, increase the breaking force on the output, it can always completely stop rotating, no matter how high the motor force is. Still kind of a good overload protection for the motor.

@ferdoreznik

2 жыл бұрын

Yes you are right. It is also motor protection. And in extra high loading the clutch oscilates and it helps to overcome some high obstacles. Its interesting concept and after many tests I realized that it is great mechanism. Especially for its small dimensions.

You can achieve that function in a better way, with a magnetic clutch, that way there's wear. You could also cascade it to make it 3 or 4 speed or whatever you want.

Dude, that was educational af -- subscribing for more like this. 👍🏻

@LucasDynamics

Жыл бұрын

I have build a even smaller automatic gearbox if you want you can check it out on my channel...