Hello all and Michael,

I am thrilled to announce I have made my first mechanism using Moi3D!

The mechanism can be seen here: https://www.instagram.com/p/CbvZN5Kl13n/

I have few questions and I have plans to share and ask more questions here.

This came to me as an idea after I saw reciprocating rack & pinion mechanism on YouTube (eg: https://www.youtube.com/watch?v=ScB6Wd4r9Jc) as well as bevel gear mechanism (eg: https://www.youtube.com/watch?v=s0kat1CUmpk)
I tried for days and made my own mechanism (I call it reciprocating bevel gear mechanism).

Note: I thought the mechanism is genuine, however, after doing some research on the internet it was proved to me that it is not genuine! because great Dr.Thang has already shared it on YouTube at least 3 months earlier! https://www.youtube.com/shorts/pOMmBK2fe8g

Question: is there anyone who has a dedicated machine who is willing to help me with animation rendering?

Dear Michael if you think this thread is irrelevant you can delete it.

Funny mecanism!
you can make it with the free SketchUp 2017 Make and the free "Physics"
MS Physics by Anton... https://sketchucation.com/pluginstore?pln=MSPhysics

Free SKetchUp 2017 Make can be downloaded here (you must have a Google account (for example Gmail) )
https://www.sketchup.com/download/all

If you don't know MS Physics take a look here
a complete tutorial ;) 26 short videos
https://www.youtube.com/watch?v=TmQ5Cei-OjI&list=PLUIFQTbizmaH1HkiRzde6Nwmrs9bAv6lD

Here the first! ;)



If you want a very cool free 2D "Physic" prog take a look to the free Algodoo!
http://www.algodoo.com

And a Reciprocating system! ;) (Algodoo 2D)
not so elegant than your...but...

Tanx for the info Pilou :)

Moi is Amazing!!!!!!!!!!!!!!! (Thank you Michael & Max (for the nodeeditor & others)

I am excited to say I was able to create my second mechanism using Moi!

it can be seen here: https://www.instagram.com/p/Cb08ycmlFmE/

I need to mention this work is inspired by Emmett Lalish (search him on youtube) & LoboCNC (search Jeff kerr on youtube)work .Note: Emmett's design consists of a five leafed iris box while LoboCNC's design is a four leafed irisbox.

Question:
I was able to do this by trial and error! ( For the designing of the leafes) Is there anyone who knows how mathematically the leaves could be designed? Does anyone know the Geometry behind it?

Edit: https://www.instagram.com/p/Cb4vUNJr_AY/ this link contains a video of the actual 3D printed iris box (The previous link is replaced!)

Very cool Iris Door/Diaphragm.
Found this link, Frank Zhao, still studying it.
https://eleccelerator.com/3d-printed-mechanical-iris-dome-all-one-piece/

and:
https://cad.onshape.com/documents/ce2b47eea2aecc8a5af6d089/w/0dd07bf8a5f9c8a8d7210b5c/e/6c2bb5a57e74b49452e98e1f

- Brian

There is a planar 5-Iris here in IGES, which loads well in MoI, and shows the various circle arcs, including the arcs of the blades.
Their radii are a bit larger than the circular hole, with centers outside of the hole. One vertex is rounded, with the pivot center.
When the Blades are closed, the angles of the arcs are 180 degrees / number of blades. (72 degrees for 5 blades.)
https://grabcad.com/library/iris-mechanism-3

For a spherical dome iris...? Spherical triangles?
Looks like the arcs would be less than great circles.
The previous paper shows a round hat on the sphere. Place 6 around the sphere, centered below the occulus, and boolean difference three adjoining hats, to make one blade...

- Brian

ps, The color used, Hex # afc4dd is very nice. To be added to my color styles.

Here is a great software to create these goofy gears.

https://www.gearotic.com/

Thank you bemfarmer,

As you might know designing of the leafs are the most difficult part of making iris box of this type! I had to put the pivot point out of the leaf body! and later connect the pivot point via a bridge; you can see it in the below image:

I will try to share my design as well after I make a video on how it could be assembled :-) (I also think I need to confess Emmett Lalish's design is way more efficient!)

but for now you can see how the 3D print works here: https://www.instagram.com/p/Cb4vUNJr_AY/

Thank you WAYNEHILL5202,

I didn't know about that link! I will dig into it! :)

With what are made the videos above seen on Instagram ?

Hi PILOU, With Keyshot!

https://www.keyshot.com/features/

Advantages:

It is easy to use! (Simple learning curve!)

Disadvantages:

it is subscription based! 99/month! :-(

I have plans to use Blender in the future! but for now I can use Keyshot! :-)

Yep indeed it's "de luxe" animation! :)

Tanx, PILOU

Hello all,

I was able to simulate a reciprocating rack & pinion mechanism in Moi3D :)

Many thanks to Brian for his explanations as how sin function works in nodeeditor as well as James. (Thank you guys)

Note: I intentionally used two different math nodes because I thought it would prevent from having messy functions ( maybe I am wrong! )

Very cool model, Psygorn!

Is the pitch line used?

Tried a slower hertz, e.g. 0.1, to see the movement.

Travel limits, and reverse may be off a bit?
Seems to have some inertia and bounce?

- Brian
(Have not studied the code yet.)

Hi Drillbit,

Looks great!

Wayne

Hi Brian,

Thanks :-)

Explanation: the movement is ideal ( I think in reality there would be some minor issues) according to my calculations by 1 Degree rotation of a Pinion the Track moves 0.15708 units depending on clock-wise or counter clock-wise rotation of the Pinion.

I hope this explanation helps :)

And thank you again for your explanation on how sin works in nodeeditor it helped me to have it work!

Hi Wayne,

Thank you :-)

And I'd be glad to know how you made the gif?