Physical Mock ups 1

[Everydaylearning]

Has anyone found some good “toys” or other objects that mechanisms can be made out of to visualize forces and motion? Sometimes it’s better to physically manipulate something rather than seeing it on a computer and 3D printing is expensive

 

[JohnRBaker]

Find some old Erector set parts...

...or Lego Technic elements...

...but if cost is not an issue, I would look into the 'simulating' product sets from Fischertechnik, a sort of cross between Erector and Lego, but on steroids...

...for more details about some of the Fischertechnik products, go to:

https://www.fischertechnik.de/en/products/simulating

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

 

[JohnRBaker]

Here's a video showing the simulation of a factory using the Fischertechnik products:

https://www.youtube.com/watch?time_continue=89&v=BApxuYlsT_w

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

 

[BrianPetersen]

Or 3D print it. Here's an awesome one (caution, some language NSFW) ...

https://www.youtube.com/watch?v=8TdmZi2E1EE

 

[3DDave]

Have you got a list of functions you'd like to demonstrate?

 

[itsmoked]

Popsicle sticks work well.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[Everydaylearning]

I'm just looking for very basic mechanisms. Right now im interested in putting together an offset slider crank mechanism. 3D printing is obviously the way to go, that was a cool video! But sadly it is too cost prohibitive right now.

 

[3DDave]

https://www.youtube.com/watch?v=YibSFhXyoUQ

using formed wire

https://www.youtube.com/user/denha/videos

an endless inspiration

https://www.youtube.com/user/thang010146/videos?shelf_index=0&view=0&sort=dd

- CAD mechanisms, by the thousands.
-> The About page for Thang:

https://www.youtube.com/user/thang010146/about

Checking for "rolling ball sculpture" and "automata" on youtube will show a vast array built using welded and soldered wire, cardboard, wood, scraps of various kinds.

One of my favorites in the genre of "Rube Goldberg" setups

https://www.youtube.com/watch?v=qybUFnY7Y8w

Done in a single take, after many, many failed ones.

As one comment goes:

Lee G
2 years ago
This video would have Rube Goldberg spinning in his grave. Which would set off a pully that sends a ball into a set of dominos. This would trigger a marble maze. The last marble would drop and hit a wooden board. The wooden board would drop and raise a big flag on a flagpole that says 'What an amazing video and song'.

 

[GregLocock]

Meccano for preference, lego techniks (sp?) these days.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

http://eng-tips.com/market.cfm?

 

[glass99]

We cut up manila folders and staple or tape them in my office all the time. Less glamorous than the Fischer technik stuff but works really well for all kinds of structural ideas. We have modeled adhesive connections, switchback stairs, wind tunnel cladding, glass cylinders, a folding mechanism for a gate, vierendeel trusses, an idea for an origami canopy and tons of other stuff. And it always saves a ton of time bc you get to the right answer and it lets the FEA just be a check.

The thing about manila folders as opposed to Lego or something is that
1. You always have materials on hand
2. you can make surfaces as well as beams
3. You can make any 2D shape or any developable surface
4. You can make "pins" with a stapler
5. Its really quick
6. its thin enough to capture buckling behaviors
7. If you add in rubber bands you can visualize stress.
8. You can print on it from CAD if you need to make accurate cutouts

I used to use foam core board, but its almost an order of magnitude slower and less flexible. I literally just start cutting with scissors and don't even trace it out with a pencil first. Bc its so cheap and quick you can afford to iterate like a dozen or more times.

We have a hot glue gun on hand too, though doesn't see much use these days. We also have a 3d printer which frankly is not very useful for this kind of thing.

 

[btrueblood]

glass99,

A utube channel I follow calls that method "CAD" - for "Cardboard Assisted Design".

 

[rb1957]

we call it "arts and crafts" ... you don't need a full CATIA model of something before you work with it !

another day in paradise, or is paradise one day closer ?

 

[chicopee]

If it is a relatively simple mechanism, I'll scale down the parts of the model,draw the model parts on thick paper, cut the drawings with scissors and connect the parts at the joints with thumbtacks, then apply movement.

 

[MacGyverS2000]

Had all three of those you mention, John... as a young-un, I was lucky enough to have a local store stock Fischer Technik kits. A bit pricey, but well worth it. Now it's near impossible to find in the States.

Dan - Owner

http://www.Hi-TecDesigns.com

 

[glass99]

btrueblood: Cardboard Assisted Design! Perfect! But I couldn't find it on YouTube. Can you post a link?

Chicopee: when you use thumbtacks, do you have a board on hand to stick them into? What receives the point?

We also do a lot of pencil sketching in the office, and a cardboard model is only one step up from that. I am a big fan of the yellow and black Staedtler Noris pencils for this purpose. Really strong german made lead which can stand up to a good argument about how a detail should be drawn, and can be used well on tracing paper in a way that mechanical pencils can't.

 

[JohnRBaker]

I had Erector sets as a kid, but it wasn't until we had our own sons before Lego's became popular. As for Fischer Technik, my interaction was visiting their operation in Germany as they were a client of ours (thy, like Lego, used our CAD system in their design and manufacturing facilities).

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

 

[btrueblood]

Glass, the series is called "Project Binky" - a couple of UK chaps modifying an original Austin Mini for AWD.

 

[CWB1]

as a young-un, I was lucky enough to have a local store stock Fischer Technik kits. A bit pricey, but well worth it. Now it's near impossible to find in the States.

I don't recall if its Jo-Ann's or Hobby Lobby, but one of the craft chains here in MI stocks a Fischer Technik. I concur with your statement about the cost being well worth it, had some as a kid and my mother bought my father and I each a kit a few years ago for Xmas.

As for modeling, I've gotten quick enough with parametric modeling that its my go-to for thought experiments.

 

[BrianPetersen]

We've used cardboard-and-duct-tape structures to see if we could fit something into a tight space without having an existing robot smash into it. If the robot does smash into it, oh well, now we know.

 

[SandCounter]

I've used card board with tacks and pencil erasers as pinned joints to demonstrate a linkage concept.

I used to count sand. Now I don't count at all.