Mechanical Buffalo – Conceptual Design

After considering several possible ideas for dynamic, fully 3D-printed toys, including things like transformers figurines and twisty puzzles, I have settled on creating a mechanical buffalo crank toy. The buffalo will have moving legs, at minimum, that will be actuated by a crank to make it appear to be running. I will ultimately create a printable kit with assembly instructions and upload it to Thingiverse for other users to replicate.

First Impressions

• “I REALLY want to print this and put it together! It’s great because it looks cool, utilizes interesting mechanical concepts, and I don’t need to go to the store to buy a bunch of extra parts to make it. I can just print everything I need right here at home.” -Thingiverse User
• “This would make a cool gift for my kid. I can even put it together with him/her to show them how it works.” -Parent
• “GO BUFFS!” -CU alum

What Will It Do?

• A crank will be used to make the legs of the buffalo move back and forth.
• As noted in ‘first impressions’, the primary aesthetics will be ‘DIY’, ‘children’s toy’, and ‘Colorado Buffaloes.’
• Stretch goal 1: Make the tail and head move too.
• Stretch goal 2: Create a model of an actual bison (rather than the CU logo) and implement the same concepts. This could change the Colorado Buffaloes aesthetic into either “nature” or “Americana” depending on other embellishments made to the final design and the user’s color choices.

Inspirations

• Twisty Puzzles (https://www.youtube.com/watch?v=83a_DX8WDe8)
• Heart gears (https://www.youtube.com/watch?v=70dKZjP4NOo)
• Transformer toys (https://youtu.be/RYQUVr4qwHc?t=3m30s — http://tfwiki.net/wiki/Bumblebee_(G1)/toys#Generation_1)
• Hand-cranked horse toy (https://s-media-cache-ak0.pinimg.com/564x/88/96/27/8896272972178cf6b3783c262e7181df.jpg – via Pinterest)
• Automata (https://www.youtube.com/watch?v=YGoVssO3yEU, https://www.youtube.com/watch?v=0gjyVqwrf3E)
• 100% 3D-printed assemblies on Thingiverse (https://www.thingiverse.com/make:150667, http://www.thingiverse.com/thing:257911 – no assembly required on this one either!)

Design Considerations

The trickiest part of this project will likely be making the mechanical buffalo user-friendly for assembly. Unfortunately, this is a problem that can only be addressed through iteration.

I plan on documenting the design process on Thingiverse. Here is my first post, which is the initial box (housing): http://www.thingiverse.com/thing:1384028. It is composed of two halves that snap-fit together using bossed features. The bottom half will ultimately serve as the chassis for the gears.

Photoview Rendering

Results of initial Makerbot Print

Budget

I don’t anticipate spending any money on this project aside from prior overhead costs. I already have over 4 kg of 3D-printer filament (black, gold, silver, white, and clear) and my own 3D-printer at home. Additionally, I have free access to the Makerbots in Fleming at any time. Once the design is finalized, I may decide to send the final version of the toy to Shapeways for a professional quality print job (~$25-$50). However, it is likely I would use a DIY method for treatment instead, especially since I already have the required materials available (http://airwolf3d.com/2013/11/26/7-steps-shiny-finish-on-abs-parts-acetone/).  Either way, I do intend to create an attractive display model!

Timeline

3/9 – Gear Design finalized, movable legs created

3/16 – System integration – gear design with movable legs

3/18 – Functioning prototype created

3/28 – Design for Assembly improvements for Thingiverse

4/6 – Stretch goals attempted by this time – decide how to proceed

4/13 – Final designs sent for professional printing (two week lead time) OR final model parts receive acetone treatment

4/15 – Final display model finished!

LET’S DO IT!

Design Review Presentation (Video)