Sequential Dual Clutch Gearbox

[Leviathan]

Hi everyone,

I just want to share with you my last functional dual clutch gearbox. It's a very long project. I wanted my own gearbox for my future Moc. Today, the best gearboxes are, on my mind, Sheepo's gearboxes, those from Sariel and NK and from France there are Steph77 and Durian for the 4 speeds gearboxes.

The box is modular. Achieved to be easily buildable. This is one of the stretch of the gearbox.

There are the gearbox features :

-Dimensions (L x W x h) : 18 x 18.5 x 8.5 cm

-Dimensions (studs) : 24 x 24 x 10

-Weight (With motors) : 620g

-Weight (Without moteurs) : 450g

-Speeds order : R - 1 - 2 - 3 - 4 - 5 - 6 - 7 - 8

With a speed of 1700tr/min ( powered by two RC motors), you have these speeds :

R :100tr/min

1 :200tr/min

2 : 220tr/min

3 : 330tr/min

4 : 350tr/min

5 : 590tr/min

6 : 650tr/min

7 : 980tr/min

The best thing is to show you all the features into a video :

Curiously, I cannot post a video correctly. May I'm not a true member yet...

The shifter is very reliable and efficient. (I do not know all the technicals english terms for my gearbox).

Explanations of the mechanism : (sorry in forward for ma bad vocabulary, but I'm a student so "listen and study" are my religion ! Let's go :

The video help a lot to complete my explanations.

There was a little bit of reverse engineering to have a reliable shifter for all the speeds. The Sheepo's PDK gearbox helped me a lot... I prefer notice that to be clear. He doesn't give me informations. I've just used the pictures on the net. That's all :)

There are two "little" gearboxes. One for even speeds + Reverse, and one for the odd speeds. A "skate" which move in translation (I'm searching a synonym of charriot in french) push each liftram as you can see on the picture. Indeed, with this system you have all yours speeds pushed sequentially. This the part of the PDK, thank Sheepo :)

On the video there isn't a reverse. Today, I found an issue to that.

Speaking about the dual clutch.

I searched for a long time before finding a reliable and strong system. I'm very proud of the result.

With one servo-motor, I control the speeds shifter and the shifter for the dual clutch. With this kind of clutch, I always have a speed activated. It's difficult to me to explain the working, but to have one clutch engaged and not the other, I use somme cams. The french PG52 helps me a lot to have a functional dual clutch.

So, finally this is my project. Now, I have a functional gearbox and I can start my next supercar (or Hypercar...)

Thank you to have read all of that. If you have some questions, it will be a pleasure to awnser you :) I think, it could more easier for me awnsering instead of introducing a complex topic

This is Leviathan, and I see you next time !

Edited March 29, 2016 by Alasdair Ryan

[Leonardo da Bricki]

Very impressive! I could understand what you meant well enough. Will there be instructions for it?

[Kit Fisto]

I second the question for the instructions!It's awesome.

[Didumos69]

Impressive work!

To post a video use exactly the format below and only replace the video id (in this case ORFjotIkhTY):

[media]http://www.youtube.com/watch?v=ORFjotIkhTY[/media]

[John Daniels]

I am thoroughly impressed, your transmission runs very smoothly, and you were able to create the proper shifting mechanism. Great job!

To embed a video you just have to remove the "s" from "https," and it should look like this:

Edit: It looks like Didumos69 beat me to it in regards to the video, and he provided an example of the code.

Edited March 29, 2016 by John Daniels

[brunojj1]

This thing is something I was thinking about some while ago. The alternating gear shifter between the 2 parallel gearboxes was the main problem I couldn´t overcome yet.

How will you connect both outputs? With a differential? Or will there be a clutch between? I also second the request for some kind of instructions, I´m curious how it works.

Hopefully it will provide the kind of heavy duty performance in a big vehicle, yes - let´s say hypercar ! Very well done !

Edited March 29, 2016 by brunojj1

[BusterHaus]

How will you connect both outputs? With a differential? Or will there be a clutch between?

If the shaft that's not active is free-running, all that's needed is a gear between the two outputs. I see the not active shafts rotate very slowly, suggesting that they are not engaged.

[Leviathan]

Thank you for all you support and for the video ahahah ! I really appreciate you messages :)

In order to answer brunojj, BusterHaus is right. When one clutch is active, the other one is free-running. So to have one transmission shaft, you have to put one gear between the two outputs. That's one my last objectives to accomplish my gearbox. I've also put a functional reverse which working ! That's fantastic, isn't it ?

To have one shaft transmission, I plug this system on the front of the gearbox :

For the others, yes there will be some instructions ! But I have to designed it on ldd before ^^

Thanks a lot,

This is Leviathan and I see you next time !

[Beard]

Great work, I will definitely try this some day.

[nerdsforprez]

This is a wonderful built and something I think the community had been thinking about for quite some time. Way too step up and produce!

[kieran]

That's nice, seems to work very well.

[CollinsLegoTechnicDen]

Can not wait for instructions mate ! looks fascinating as heck ;)

[Leviathan]

Hi everyone !

Here my progress on my gearbox. I've just finished a new version, more reliable and more compact.

I think it's could be a good idea to poll up this topic because the TLC Porsche is coming and maybe some people wanted to put a real dual clutch gearbox into the car ^^ instead of the 4R + 4D one...

The new gearbox volume is optimized about 20%. It is very interessant into a moc to have a gearbox which spends less space. In addition, the rear differential is placed directly into the box to earn space. All the design is based on modularity. Each component (rear axle, dual clutch, ...) is design separately. The assembly is very fun like the old one.

We have the same specifications that the old one. So, there is not a video.

There is a servo for the two shifters and two RC motors for the transmission and a grand total of 8 speeds.

The gearbox is very optimized for 1/9 scale and more for 1/8 scale. The box is also ready for 1/10 scale but if you want put this gearbox on it, you must certainly add some modifications. However, it's still possible, trust me.

The new dimensions are in studs :

- 16 x 16 x 9 (Lenght x width x hight)

Let's go, photos :

A comparison with the old one. She looks like smaller, isn't it ?

If you have any questions or suggestions, it will be a pleasure to answer to it.

I'll see you next time !

[MRP_]

My goal in life, is to someday, come close to starting to think about learning how to begin to understand this.

[tomek9210]

Nice job making it smaller! What car are you going to build?

[arshiaIQ]

Oh great... after a long time we're seeing a new sequential gearbox...

Great mechanism!

How much is it reliable?

What is it going to be? Is it a model of a real car?

Also would you make a 3D model of it? Or a photo sequence while building one? Youll receive great feedbacks!

Goodluck!

[arshiaIQ]

Anybody here? Why is this topic dead? Author please help me... Im really interested in it

[Leviathan]

Thank for your returns :)

You think this topic is dead, come on see it on Techlug... ^^

The question of reliability is a hard one. Into the box, there are two critical mechanisms : The dual clutch and the speeds shifter. The dual clutch is 100% reliable. No fails during my trials. However, the shifter is not 100% efficient. There are some fails between the reverse and and the speed one. I really have to find an issue to that. So I could say for the shifter, 90% reliable.

This a part of the Bugatti Veyron gearbox. But, the Porsche gt rs is coming, so I'll replace the original 4 speeds + 4 reverse by my dual clutch sequential gearbox. Today, a lot of sport car have a gearbox like this one. So I really want to build an universal chassis to build all super cars I want :)

I started instruction on LDD but it is very long and I don't want to spend my time on it. So I will make certainly photo sequence like you say when I'll correct all my currents problems on the gearbox.

I really want to share this model but I want to share something easy to build without settings and illegals builds.

If you have questions, do not hesitate to ask me :)

[tomek9210]

Have you tested it under some load? Isn't there too much friction on some gears? No gears grinding?

[Leviathan]

Have you tested it under some load? Isn't there too much friction on some gears? No gears grinding?

I'm on it ! I'm building a little chassis to test the gearbox on the road. It'is sooooo fun !! I put Two bb on it for simulate a charge. There is no friction on gear whatever the speed. I saw some grinding when you walk against a wall but that is normal :)

The seventh speed is very powerful. However, the movement is not very linear, it is jerky. I don't know why. When I remove the wheels, the problem disappear. My future Moc will be a 4x4 transmission so this is not a problem for me today.

I will post a video soon because it 's amazing to see the gearbox move alone on the floor !

[tomek9210]

It is jerky because of the space between teeth of each gear. When you add many gears, there is a lot of space and it takes some time before power is transferred to wheels. Also clutch gears have teeth too and axle needs to be rotated a bit before gear is engaged.

[Leviathan]

It is jerky because of the space between teeth of each gear. When you add many gears, there is a lot of space and it takes some time before power is transferred to wheels. Also clutch gears have teeth too and axle needs to be rotated a bit before gear is engaged.

No I don't talking about that kind jerky. I'm talking about my non linearity of my movement. When you start the motor you have a little gap of time before engage the movement like you say. But you only have this problem at the beginning. One of the advantages of the dual clutch is a shifting very smooth.

I'm talking about a displacement on the floor in the same direction not linear, with some jerk. It's very visible when the speed is low. Today I can't explain that. I really have to make a video to explain that.

[arshiaIQ]

Thank for your returns :)

You think this topic is dead, come on see it on Techlug... ^^

The question of reliability is a hard one. Into the box, there are two critical mechanisms : The dual clutch and the speeds shifter. The dual clutch is 100% reliable. No fails during my trials. However, the shifter is not 100% efficient. There are some fails between the reverse and and the speed one. I really have to find an issue to that. So I could say for the shifter, 90% reliable.

This a part of the Bugatti Veyron gearbox. But, the Porsche gt rs is coming, so I'll replace the original 4 speeds + 4 reverse by my dual clutch sequential gearbox. Today, a lot of sport car have a gearbox like this one. So I really want to build an universal chassis to build all super cars I want :)

I started instruction on LDD but it is very long and I don't want to spend my time on it. So I will make certainly photo sequence like you say when I'll correct all my currents problems on the gearbox.

I really want to share this model but I want to share something easy to build without settings and illegals builds.

If you have questions, do not hesitate to ask me :)

Take the photo sequence and dont wait to make it perfect, we'll help you to make it best, maybe i could do smtng with the shifter mechanism... ive spent a lot of time for making reliable shifters

If you use sheepo's bugatti shifter, ive to say it doesent work at all without certain bands

[tomek9210]

Is the 2L yellow axle connector at the front the input? Is it possible to make it AWD?

[Leviathan]

ive spent a lot of time for making reliable shifters

If you use sheepo's bugatti shifter, ive to say it doesent work at all without certain bands

I don't use sheep's bugatti shifter, neither Shelby's shifter. I've reproduce the Porsche Pdk shifter to shift up down speeds. On my gearbox, I've really optimized it to make it more reliable and more smaller. The second shifter for the dual clutch is a French one. The designer is Steph77. I've improve it to be torque resistant. This shitter is 100% reliable.

Update :

I ve finished the first shifter to make it 100% reliable. It's done ! I'll publish more information soon :)

Is the 2L yellow axle connector at the front the input? Is it possible to make it AWD?

So, that is one of the skills on the gearbox. You can have a RWD, AWD or FWD because the yellow axle connector is the.... output !

I explain myself :

On this picture, on the left you have two yellow axles connectors, right ? They are the two inputs. One for each RC motor. The power is distributed on the two mini gearboxes and you finally have two inputs. One directly on the differential (on the left) and one at the front (on the right). So you can do whatever transmission you want.

If you have any questions, please ask me :)