Triple Axis Augmented Crate

Hi, wonderful people!

Yay, complicated motion! Why have one hinge point for a lid when you can have three, right?! But seriously, this ridiculously complicated motion structure does achieve something significant - it allow the lid to pivot over the back of the box and end up flat against the back, vertically. And more importantly it's mesmerising!

It's perhaps surprising, though that designing the pivoting motion was not the time- consuming part of the model - that was achieved by drawing arcs and moving pivot points around until the motion worked in a way that allowed struts to be located in places that worked for printing without supports. The tough bit was actually testing the moving parts and discovering which things in real life did not move the way they were supposed to.

In the abstract, a hinge joint should move in a rotational way, but the reality is that a printed hinge has a gap in it or else it would be a single piece of plastic. And this means that parts move up and down and back and forth depending on the forces involved. This can become a huge problem when there are multiple parts involved, and they all move in an inconvenient way, because things get jammed and stuck.

Fortunately, there are ways to mitigate this! Sometimes it's as simple as making sure the space between two parts is slightly greater than the interior movement potential in the hinge, but that isn't always practical. So, we end up with things like little ramps that intercept a colliding part and redirect somewhere more desirable. You can see these things in action in the Axial Augmentation Crate lid - the parts all naturally sag with gravity as the lid is raised from the front, and then the parts shift into each other, but instead of getting jammed together they are gently coerced into rotating, and then everything is nice and smooth.

Print Description

This is an articulated, print-in-place model so make sure your first layer is nice and neat and that there aren't any print artifacts like stringing or overextrusion that might bond moving parts together!

Print Dimensions

The Triple Axis Augmented Crate occupies 124mm x 179mm on the build plate and is 179mm tall.

Supports Needed?

Not at all!  Designed for straightforward printing!

Scalability

This should scale reasonably well - tolerances are generous enough to handle significant scaling down (I printed it just fine at 60%) and large enough to allow for upscaling (though no guarantees for what happens to the motion when the tolerances increase! :P)

Print Orientation

The model prints upside-down, with the articulated lid on the print bed.

Further Thoughts

This does make me wonder if there's some way to take advantage of the locking propensity of hinges... could things be jammed up together intentionally to drive a particular type of motion?

Happy printing!

xoxo

Sven.

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480 Triple Axis Augmented Crate