[TC12] The Unrollable

[Lipko]

I think the cabin just pops out on the other side (with the help of yellow shocks) and only the seat and the steering wheels rotate.

[kodlovag]

Thank you for commenting, I'm happy you like it.

5 hours ago, BusterHaus said:

How does the seat switch orientation to keep the driver's head up?  I can't figure out - it seems like the seat is too wide to rotate inside the cage, and from what I can see the cage doesn't rotate...

 

2 hours ago, BrickbyBrickTechnic said:

I agree with this. Will there be a video?

 

5 minutes ago, Lipko said:

I think the cabin just pops out on the other side (with the help of yellow shocks) and only the seat and the steering wheels rotate.

Exactly, the cabin only flips to the other side, and only the seat with the steering wheel rotates. This is the 3rd or 4th version of the seat, which finally can rotate around inside the cage. All the previous versions were too wide or too tall, and got stuck into the roof. I plan to make a video later, when I start building from real bricks. Since that I will try to make some pictures in LDD, which shows the seat in rotation.

20 hours ago, MangaNOID said:

I guess the driver would have to slamm the gears into the reverse set of gears too if the car flips? will the model be free rolling or do you have drive gears etc to hook up?

also looks like you need a double, double deffuser or once upside down the car would not be as aerodynamic

Edit: I just re read the first topic post 

On the white side the diffuser supposed to be a down-force wing, to keep the aerodynamics. It would be useful to have the wing one stud higher, but at this moment I can't see a way do dynamically lift it.

[BusterHaus]

@kodlovag Thanks for the explanation, can't wait to see the seat in action! 

[mocbuild101]

It's not the whole cabin that rotates, it's just the seat and steering wheel...

Edit: whoops... I didn't see the second page

 

Edited September 6, 2017 by mocbuild101

[Didumos69]

Sorry, didn't see the last few posts.

Edited September 6, 2017 by Didumos69

[mocbuild101]

27 minutes ago, Didumos69 said:

Sorry, didn't see the last few posts.

So I'm not the only one that made that mistake!

[agrof]

Might be not the most wacky, but the concept itself is really remarkable! I do like the overall design too, homogeneous, sleek, nice to look at. Great build so far. 

[kodlovag]

Long time since the last post. I found some of the missing parts in PaB walls of a LEGO store, and ordered the rest from Bricklink, and waiting to arrive. It took some time to order, becasue I collected them together with the parts for my modular building. Hopefully, by the end of the week they will be there. Then I can start building. I can't wait

[Boulderer]

Do I understand correctly, that you find Technic pieces in your local PaB wall?  I've never seen a single Technic piece in all my visits. 

[Marxpek]

This is one great design, i do miss the wacky part a bit, but it is an amazing car!

[kodlovag]

On 2017. 09. 18. at 3:48 PM, Boulderer said:

Do I understand correctly, that you find Technic pieces in your local PaB wall?  I've never seen a single Technic piece in all my visits. 

I was inaccurate. There is a normal PaB wall, however it never had any Technis parts. But there is additional bulk Lego in big bins, separated by color families. It contains a selection of parts currently in manufacturing, all brand new, many hundred different pieces. Sometimes you can find expensive and rare bricks, and there are Technic parts too. But Technic is very limited, usually axles, pins and connectors are available, while gears and long liftarms are definitely rare.

During my last visit I could only find normal bricks missing from the front of the car, but I was unlucky with parts 22961 and 87082, which I still need.

[Boulderer]

The bins of pieces isn't something I've seen at the Lego stores here in the UK.  Sounds like a treasure trove of fun 

I can now say that I've seen technic pieces at a PaB wall!  Found 12l Axles and 1x12 technic bricks (red) at the PaB at Manchester Lego Discovery Centre Shop.  It's one of the smallest PaB walls I've seen but, the first to have stocked technic pieces. 

Edited September 29, 2017 by Boulderer
Update on PaB wall contents.

[kodlovag]

Finally, I have the missing pieces, and could start building. Yesterday I completed the version 1. The steering, engine, flipping mechanism and rotating seats are all work.

Unfortunately, there will be a version 2, because I have serious problems with the rear suspension. By design, the rear suspension use the same shock absorbers, as the flipping mechanism. But the shock absorber has the hard spring, and instead of compressing the springs, it bends the suspension arms back. I already tried to strengthen the chassis at the rear suspension, but it doesn't help at all, the suspension arms still bend back by approx 1/2 stud. I cannot try a soft spring, because I don't have any, just the yellow hard. And I'm afraid, that the problem is worse, than just a spring hardness. It could be on the design level, because the 60 degrees spring orientation relative to vertical is too far from the ideal parallel, and in case of compressed spring the value is even worse.

I don't want to turn off the rear suspension, but I have no idea, what can I try. Maybe some rubber based suspension...

[Didumos69]

12 minutes ago, kodlovag said:

And I'm afraid, that the problem is worse, than just a spring hardness. It could be on the design level, because the 60 degrees spring orientation relative to vertical is too far from the ideal parallel, and in case of compressed spring the value is even worse.

I also think this is a design issue, it probably also causes friction in the suspension arm movement. Can't you make it symmetrical, with angled springs coming from both the back and the front, or would the suspension be too rigid? EDIT: bad idea, the rear spring would not flip along with the front spring.

EDIT2: Maybe with a spring coming in from the back that is even more slanted, with the rear end of the spring centered between the outer positions of its front end. Btw, I would also try to get rid of the ball-joints in the rear suspension so there is no need for the stabilizing links.

Edited October 1, 2017 by Didumos69

[Leonard Goldstein]

1 hour ago, kodlovag said:

Finally, I have the missing pieces, and could start building. Yesterday I completed the version 1. The steering, engine, flipping mechanism and rotating seats are all work.

Unfortunately, there will be a version 2, because I have serious problems with the rear suspension. By design, the rear suspension use the same shock absorbers, as the flipping mechanism. But the shock absorber has the hard spring, and instead of compressing the springs, it bends the suspension arms back. I already tried to strengthen the chassis at the rear suspension, but it doesn't help at all, the suspension arms still bend back by approx 1/2 stud. I cannot try a soft spring, because I don't have any, just the yellow hard. And I'm afraid, that the problem is worse, than just a spring hardness. It could be on the design level, because the 60 degrees spring orientation relative to vertical is too far from the ideal parallel, and in case of compressed spring the value is even worse.

I don't want to turn off the rear suspension, but I have no idea, what can I try. Maybe some rubber based suspension...

Hi kodlovag,

maybe you could arrange the suspension arms parallel to the driving direction. And if the arms would be close to the spring, there would be almost no bending, just tension in the suspension arm. Of course there will be a little change of distance between the wheels and the differential. With a cardan ball (32494) instead of a universial joint (61903) you could compansate this.

Edit: Great design by the way!! I hope you can solve the problems and make it to the contest!

Greetings

Leonard_Goldstein

Edited October 1, 2017 by Leonard Goldstein

[kodlovag]

Whoohoo... The rear suspension finally works!

On 2017. 10. 01. at 4:54 PM, Didumos69 said:

EDIT2: Maybe with a spring coming in from the back that is even more slanted, with the rear end of the spring centered between the outer positions of its front end. Btw, I would also try to get rid of the ball-joints in the rear suspension so there is no need for the stabilizing links

 

On 2017. 10. 01. at 6:47 PM, Leonard Goldstein said:

maybe you could arrange the suspension arms parallel to the driving direction. And if the arms would be close to the spring, there would be almost no bending, just tension in the suspension arm. Of course there will be a little change of distance between the wheels and the differential. With a cardan ball (32494) instead of a universial joint (61903) you could compansate this.

Thanks for the suggestions. I also discussed the issue with my brother (he's not a Lego fan, but building and racing with model cars and has closely related experience), and he came with a ton of ideas. Mostly bad, but one worked perfectly. I had only one link in the rear suspension, and I had to remove the other, because it collided with the spring. But therefore I had a free ball joint on the steering hub. I attached a stabilizer link to it, and set it to the driving direction, and fixed it to the chassis under the side boxes. It's so simple... Now the suspansion arm is absolutely stable, and cannot bend a single mm backward. And the rear suspension started to work immediately! Very similar idea to Leonards suggestion, but the arms are not rearranged, just an extra link is added.

Before this I also tried my idea with the rubber based symmetric suspension, but I failed. Theoretically it could work, but requires very strong rubber belt with very precisely set length. And I failed to set the length. Furthermore I planned to use non-Lego rubber belt, which would be probably aginst the rules.

So yesterday night I fully assembled the car. The rear suspension still has to be fine tuned, and I have to increase the length of the car by 1 stud, because the side panels limit the free movement of the rear suspension. But I can see the light at the end of the tunnel.

[Didumos69]

That's great news! I can't wait to see images and eventually a video.

[Boulderer]

I'm really looking forward to seeing the final outcome of this build.  

[doug72]

Nice digital images but when are we going to see WIP images of actual construction ?

Edited October 3, 2017 by Doug72

[kodlovag]

15 hours ago, Doug72 said:

Nice digital images but when are we going to see WIP images of actual construction ?

I plan to take photos tonight. I have to charge the battery of my camera. In worst case I will use my phone. I prefer showing LDD images during the design and construction process, they are more clear (at least for me). I don't have too much Technic parts, and I have to disassemble previous MOC to build something new. I never risk the existence of a good MOC just to try something new and fail. I design everything digitally, and only when I think it is good enough and I have all the necessary parts, will start disassembling the old MOC and building the new one. In my real life I also design everything in CAD software before paying a single EUR for the prototype. During the design process I can only show LDD images, while the actual construction takes only 1-2 days. Then I can show real photos of the completed MOC.

On 2017. 09. 18. at 5:33 PM, Marxpek said:

This is one great design, i do miss the wacky part a bit, but it is an amazing car!

 

On 2017. 09. 06. at 9:05 AM, agrof said:

Might be not the most wacky, but the concept itself is really remarkable! I do like the overall design too, homogeneous, sleek, nice to look at. Great build so far. 

 

On 2017. 10. 02. at 4:01 PM, Jim said:

Hi,

Back from my holiday, which means back online again.

This is a message to inform you that voting will be a little bit different for this (and maybe future) contest. Voting will consist of a public part (members) and a jury part (undisclosed group of selected professionals  ). More information will be disclosed in due time. The purpose of this voting scheme is to give people who build in the spirit of the contest a better chance to win (instead of high scores for things that simply look cool). Another benefit is that people are not able to calculate the winner beforehand.

 

I have a bad feeling... I read through the Contest Information Topic and the Entry Topic, watched the videos, evaluated the opponents, and so on. I feel, my car is not wacky enough. Especially if I compare against for example Doug's Boydell Stomper.

I need more WACKYNESS!

So I decided to upgarde the car to 4 wheels drive... in a wacky way. The rear wheels are already have drive, the fake 2 cylinder engine. The front drive requires some extra parts:

• 2 pcs of 6x6 radar dishes
• 2 hamsters

One for each wheel . In case the fuel tank is empty, or engine malfunction, the car will be powered by the hamster wheels! The race has to be finished!

[Didumos69]

Although understandable, I think it's a pitty you genuflect to people complaining about not wacky enough. In my opinion your rolling over feature combines wacky and classy in an excellent way. No need to go the less serious direction imo. But it's your build of course.

[MangaNOID]

I was really looking forward to this car without too much overt wackiness. Even though as @Didumos69 has pointed out the concept is still wacky. Either way I'm still looking forward to this cars finish. 

I Ve already been thinking how this could be automated on rollover to automatically reverse the wheel direction so the vehicle carries on going forward.

[kodlovag]

46 minutes ago, MangaNOID said:

I was really looking forward to this car without too much overt wackiness. Even though as @Didumos69 has pointed out the concept is still wacky. Either way I'm still looking forward to this cars finish. 

I Ve already been thinking how this could be automated on rollover to automatically reverse the wheel direction so the vehicle carries on going forward.

What do you mean reversing the wheel direction? There is no PF in this car. I'm pushing it forward. After rollover I'm still pushing it forward. The engine will rotate in the opposite direction, but who cares? The same is true for the cabin steering wheel: works correctly only at one state of the car, and reverse way after rollover. But the other steering point over the front wheel works correctly on both state of the car.  I already proved it to myself, that there is no such fixed mechanism, which allows correctly working cabin steering in both state of the car, because of symmetry reasons. Maybe it could be done with gears, which moving with gravity. Like in a transmission, which could be set to reverse. Only difference would be, that gravity set the driving ring, instead of a manual switching arm. But there is simply no space for such a mechanism in this compact car. Compact is relative to other supercars, it's only ~660 parts, and most of the usable space is occupied by the flipping cabin. So all functionalities were simplified as much as possible, while keeping the fun and the playability.

[kodlovag]

And some real photos, as I promised. See my flickr album to see more

I'm not sure if there are 3 good photos there. I definitely have to repeat the whole photo session at daylight. Probably during the weekend.

[MangaNOID]

I know it's all manual but I'm thinking how to make it auto (for myself)