42128 C Model - Fairground Tilting multiple spinning platforms

[Mr Jos]

After my B-Model where I couldn't use the turntable available in the 42128 [Heavy-Duty Tow Truck], I wanted to make something usefull with as many as possible functions going on around that piece.

I came up with a tilting platform fairground attraction.

 

Functions (only 42128 pieces):

 - Manual tiltable platform with pneumatic pump and 2x 1x11 cylinders.

 - Manual control for spinning the platform at base with knob.

 - Manual control for spinning an element on the 4 arms (I added 4 minifigs for seeing better the movement of these platforms) at base with knob.

 - Full walking platform closed for walking when cylinders in lowest position for boarding.

The 2 spinning functions are not linked together, they can be controlled individually.

Platform going up:

 

Functions (with extra pieces): Compressor not made yet, I will try to make it with minimal extra pieces, I'll try only 2/4 pumps and few T-pieces. If possible all liftarms from 42128 set.

 - Compressor driven by controlable motor for speed/height of the platform moving up/down.

 - Controlable motor for controlling the valve (no need for extra pieces, only motor)

 - Controlable motor for spinning the whole platform.

 - Controlable motor for spinning the 4 arms mini platforms.

All items I think that will be needed to do this is in this picture on the left side. I will try to use the PS4 controller for controlling all movements.

 

The name of this MOC is fitting for the minifigs, that can end up spinning very fast in all directions.

Depending if there's a need I will make a video of this. It's here

 

Edited August 12, 2021 by Mr Jos

[Mr Jos]

Manual control mode;

Automatic control mode; I tried to make it simple, put all 3 motors on in 1 time with 1 point locking it in place with a 3L pin with bush.

The compressor is in parallel with the manual pump, that still works.

 

I made a small program with Pybricks MicroPython controlling it with the PS4 controller, and it works, but the motor for the valve is not strong enough for precise control. I will try to add some gearing to it and see what happens.

Compressor frame made completely with items from the 42128. Only things added 4x 5,5L pump, 5x T piece, manometer to see the pressure doesn't go to high. ~1 bar is needed for lifting the platform.

Edited August 11, 2021 by Mr Jos

[Mr Jos]

Found some time for a video

Motorized control with EV3, programmed with Pybricks MicroPython, PS4 controller used with Bluetooth.

Big thanks @Pybricks for making all my projects possible, easy to control motor speeds as you can see in the video, slow ramping up/down for the platform motors etc.

Edited August 11, 2021 by Mr Jos

[Mr Jos]

5 hours of 3D Modelling in correct order steps later,

Thought more people would be interested in combining multiple movements through a turntable, that is moveable itselve, whilst maintaining it as a very small footprint, but guess I was wrong. This wasn't a MOC to make a fairground, but just to prove the TECHNIC possibilities of combined pneumatics, turntables, gearing etc in narrow spaces.

That's why I won't put time into making instructions for this one, but I can use the 3D model to recreate this if I ever want to display it anywhere, or at a STEM learning point. Guess I'll only post here another MOC if I make a Supercar or Truck (Which I will never do, I only make things no one else would think of, or think would be possible).

/End of monologue.

Edited August 12, 2021 by Mr Jos
Removed some frustration

[Gray Gear]

Its a weird ride but kind of cool that it works using pneumatics 

[Brickend]

I'm sure a lot of people appreciated the effort to goes into creating presentations but I'd also imagine there were quite a few who perhaps felt a tiny bit mislead by the title and the relative quantity of EV3 needed, which in itself massively narrows the audience?

What it does demonstrate to me is that a really good fairground ride truck could be built out of 42128.

[Mr Jos]

4 hours ago, Brickend said:

I'm sure a lot of people appreciated the effort to goes into creating presentations but I'd also imagine there were quite a few who perhaps felt a tiny bit mislead by the title and the relative quantity of EV3 needed, which in itself massively narrows the audience?

What it does demonstrate to me is that a really good fairground ride truck could be built out of 42128.

Title I have to say was found from wikipedia, as I couldn't find a name for it. It seems wikipedia put all fairground attractions that move in more then 1 direction in the group "Spin 'n Puke", and as I didn't find a fitting one I sticked with the groupname.

First and most important part was that it would work with only 42128 parts, EV3 came only into play once it worked, as that's what I like to do, making things work remotely. My B model even didn't use EV3, no fancy name. As far as I know it's the first (published) forklift using (multistage) pneumatics and no gear rack/only string on reel for pulling up.

Could I have made way better/nicer models with same functions? Hell yes if I din't limit myselve to this set's parts. At this moment doing right that, I threw everything from 42128 into a ziplock bag keeping it separate from my usual LBG bricks, and started making a bigger version of this fairground ride but LBG/black/yellow only, that will have full size carts spinning instead of just the minifigs in this C-model. I was limited with the low amount of panels in the set keeping me from making it big enough to have carts where the figs could sit in.

The real life possibilities for this (In this video where I start it) ride #6, #5, #4 and #1. All hydraulic lifting platform rides with more movements on the platform unlike a centrifuge that only rotates the platform rapidly.

Edit: Tried to rename the topic title to generic. But it seems you can't change topic names (or I can't find where). Thanks @Gray Gear

Edited August 12, 2021 by Mr Jos

[Gray Gear]

@Mr Jos just click "edit" on the original poast 

[Mr Jos]

Thanks,

And now a 'small' challenge, as it's to make it as small as possible.

 - It should stay within the width of a Type 3 turntable preferably and stay as low profile as possible underneath the turntable.

 - 3 independent movements being 90° on the incoming axles. #1 = Turntable Type 3, #2 and #3 should be coming from under the turntable (fixed chassis) and ending up above the turntable, so it can move something above it.

 - Bonus points; Have all 3 incoming axles in 1 plane parallel with the turntable (this is needed for a tilting arm, as the 3 axles will need a universal joint right in the turning point of the arm at the bottom).

- Jackpot; Having no parts at the opposite side of the input axle (on my photo, right side of turntable should not have anything underneath. (From center to right side as less as possible items)

 - All gearing has to be strong guided so gears will not skip with some resistance put on the output.

This is a pretty Technic challenge, many will not even think about what is underneath/inside a machine.

This kind of build could not only be used for a attraction like this, but also on a truck/construction equipment etc...

A little help as what I've come up with today so far,

3 Long axles are temporary for building more and checking what length axle will be needed next, these are the inputs being all in the same plane, with 1 stud between them.

- Output Turntable, red gear and tan gear all turn independent with the ability to withstand some force applied on them.

- Height under turntable 4studs, width 7 studs max.

- Length from center turntable to last gears needed 8studs, this could maybe be shorter but the length doesn't matter to me.

 

Finding the Technic limits with Lego, that's what I try to find (and fail many times of course, but I keep trying.

[Mr Jos]

And a working solution so far, 5 stud wide arm (can't go smaller I think? Support arms are needed for the pivot points next to the axles. Yellow input axle turns the red output gear. Grey input the tan one. Black rotates the turntable. Maximum angle for lifting the arm is 45°, found out in the previous build the universal joints don't like more than that anyway.

Whole arm could be much shorter, I added 12L axles with long connectors just for making it longer to have a big workplace for making the top construction.

Edited August 13, 2021 by Mr Jos

[pleegwat]

I've been nerdsniped on this. The shallowest way to pass a second function through a turntable is the blue 20z double bevel gear with pinhole. You can interact with this from both sides with 12z single bevel gears in the same layer as the turntable's mounting holes, and the axles for that can run through the mounting holes.

The problem, then, is how to make your way in for the other two functions. Particularly the gear driving the turntable you generally want to be in the same place.