Lego Technic Automatic 4-speed Transmission Prototype

[jonhlennon]

I am more impressed on how you managed to create a 'resistance sensor' with the rubber band and the lever.

Using a diff and a rubber band to measure resistance? Someone, give this man a job at LEGO.

[fuchs_]

The problem is, that the clutches aren't getting locked in perfectly, the angle of the clutch stepper, is only sometimes in the perfect 90 degree position needed, to have a flawless shift. If you would just simply ad a 90 degree stepper to the clutch stepper as for example used in the bugatti chiron you could get rid of the stepper standing at a wrong angle. The transmission would then not shift in a liniear motion but in 4 steps, which will make it more accurate and stabalized in 2nd and 3rd gear.

Pls like so he can see.

Edit: Yo grammar police chill down, im fqin German

2nd Edit: You could try using the axle connectors with the clicking mechanism instead of the smooth connectors, where the clutch moves freely. Could work too, because the gears kinda click and lock in place and a certain amount of tension is needed to reach the next gear. Replacing one of the axle-connectors should be enough.

[theq]

Sariel: I've run out of ideas on how to improve this.
Me: All is lost if this genius cant crack it.

[TechnoFishlego]

Finally and automatic transmission that works

[willtubes]

I've probably been subscribed to you since about 2015. Not sure of the exact date, but I'm always glad to see an email notifying me that you uploaded a video!

[ssisk]

Bro...
Most people: Look, I made a car out of Lego...
Sariel: I made a self adjusting automatic transmission, it's not perfect can you guys give me ideas on how to perfect it?
The rest of us:... ... This guy made an automatic transmission out of Lego?... Can barely comprehend that let alone help you lol...
Nah but seriously good luck on it, that's a game changer right there...

[Stigsens]

I was building lego since i was a baby, 49 years ago. (Being from Denmark) when I see what you guys come up with, i get so so humble and proud at the same time. That a tiny (in the start) company in Denmark produce small plastic bits, that can be used like this. You guys are so creative....

[zemax]

My engineering teacher : where did you get those mechanics knowledge?






Me: you wouldn't get it

[Krish]

Lego is such an amazing thing, as a kid me and my dad we've always played with Legos mostly with the old technics sets and I think it helped me a lot to get the necessary skills and mindset to mechanical things. Now as a grown up I fix aircrafts but I'm sure it all started with Legos.

[PhoenixClank]

This is brilliant! I've seen this concept applied to 2-speed transmissions, but I would have never thought about something like this!
As for the stalling in "neutral", maybe the gap between consecutive gears wouldn't be as large if you built a true dual-clutch gearbox? It would probably be a lot bulkier. I know Sheepo built a PDK for his Porsche model, with actual (rubber-based, I think) clutches instead of relying on these transmission rings.

[tthe_scotsman]

That is absolutely ingenious! Apart from designing a whole bloody transmission! The rubber band design is just superb! Amazing work!

[peregreena]

When the clutch decouples for shifting down gear, the torque goes to zero and the mechanism goes into shift up mode. There is a delay because the mechanism takes some time to go from down to up shifting. Only when the down shifting is complete before the mechanism is into up shifting mode, the shift is successful.
So a further delay would make downshifting more reliable. It could be done with a directional friction brake on the gear selector wheel.
Or maybe freeze the gear selector in place until the shift has completed.

[tymt]

That differential and rubber band mechanism is very impressive, I never would’ve come up with that. Great job

[coopervanbonn]

I’m so glad that we finally have a 2nd (That I know of) automatic transmission in this hobby. I built the version from Lego Technic Mastery, but the frame was very odd and hard to fit into a model, in addition to only having 2 gears. (It’s a fantastic design still, and very compact, I just never plan for these things haha) I would imagine that playing with the tension of both the stepper band and the shifter band could be used to find a ratio that would be smoothest? Just an idea. Now, back to building! 🐶

[jessicacopeland]

Great video!

Shift solution: PRE-SELECT CIRCUIT (same method used in automotive automatics)

It helps to have two tension loads, but you can do it with the one.

1st- adjust the shift mechanism to operate at a higher tension on the rubber band (this would be the same as increasing line pressure in a hydraulically controlled transmission)

2- separate your up/down shift linkages and circuits

3- use coilover shock pieces, or two pulleys and another rubber band for secondary/auxiliary energy storage, with a ratchet mechanism to contain it until the shift is required

5- can either use cams (as you used for shift circuits) or any other type of rapid release mechanism to release energy from the auxiliary so the the full engagement is made independently from input rotation.

This would be similar to a ratchet shifter used in cheap drag cars. The other option would be either a dual clutch mechanism, or spring loaded bending type ratchet engagement. In the latter, you replace the clutches with ratchet mechanisms (free rotation in one direction, engaged in the other). You can use a simple rocker mechanism to switch between the two. Be sure to have the input side with a spring pretension to alleviate hard shifts or skipped shifts (and associated gear damage).

[cmetaphor]

Awesome work as always. What about some sort of centrifugal clutch mechanism? It would be too big, but might work. Or even several clutches with varying degrees of force needed to engage.

In my head it would work backwards, with the least amount of resistance on the output shaft, all four clutches are engaged, as the force builds, the weakest slips, causing the gear ratio change when only 3 clutches ares spinning. Etc etc until only the last clutch has engaged (1st gear) or could even be adjusted to slip to prevent over-stressing the motor?

Grain of salt. I've got ideas in my head but not enough experience (yet) to implement it. I just know I've seen functional clutches in Lego in the past. 🤷‍♂️

[MrWraith]

I don’t care what people thing or say about this. But this dude made something insane. I never thought it could be done. But they did it.

[StrxngeThings]

Never have I seen such detailed videos like this, I just want to say that whatever you are doing keep it up, favorite channel at the moment. Cheers lad. Also tell the hamsters I said hi. :)

[thettguy]

living the dream man. My 10 year old self wanted to do this project 43 years ago. Congratulations.