Lets Discuss.. How the Enchanted Mirror achieves it's Transformation

C can't be U shape because you'd see it as the mirror moves both wide and down at the same time. Again, the only way that would work is if there is nothing behind the mirror where it grows horizontally. For that to work, the mirror can only grow the width of the mirror's frame sides. Else, you'd see the gap when the mirror is in the start position or you'd see the U shape when it was opening.

Trust me, I worked through this as well and was my first thought because of the chair rail piece made it seem obvious as a place to hide a seam. I was also thrown when the chair rail wasn't atthe bottom of the mirror.. but like Rob posted, it's actually aligned with the top edge of the mirror frame which is more than coincidental

Looking at the video again (now that I'm at the computer), it would appear the mirror only grows horizontally LESS than the width of the mirror frame.. which was the requirement for this to be.. So it is quite possible to only have C move, be U shape, and the U is actually the size of the final opening.. with the rest of the space simply being covered by the mirror frame iself.. and no wall at all. Nice eyes @Rob562 - the dimensions seem to work for this as I look again.

Let me do a new graphic..

So do we think the chair rail moves into the vertical column as the mirror expands, or does the mirror just float over top of it as the mirror expands? Simplicity in design would say float over it... less moving parts. Any proposed ideas?

Ok, here's a new image showing the sliding surface and the wall being only the bottom panel.

Rob's observations made me go back and reconsider that layout (trust me, I tried over and over to make it work) but the conclusion shows the importance of little things can lead to great simplifications. By selecting the size of the mirror frame itself correctly, you can achieve a great simplification of the solution. This is seen in programming, engineering, design, etc.. elegance often comes from very specific choices.

That said.. here's my new animation. I don't have any lingering concerns about it except it would be interesting to know how the frame is articulated itself. The transparency tries to illustrate how the fixed wall is not really behind the mirror frame in the start position, but rather the opening matches the final position of the mirror. Purple is the pink wall behind the fixed wall...

Yup, that's it.

You mentioning the chair rail got me thinking that it, too *might* move and be what the frame sides are attached to. That would allow the horizontal stretch and the vertical stretch be able to independently move from each other. The bottom frame would just have to be "linked" somehow with a free-moving point to allow the bottom frame to pull down the telescoping sides no matter what position the sides are in.

Having the chair rail move would also make for a solid join between the frame and the rail so that they wouldn't have to design a cutout in the side edge of the frame for the rail to go underneath.

-Rob

the fact the mirror frame slides down over the chair rail after it has moved outward is what makes me think hard.. this would require a gap behind the mirror at the start point if the rail didn't move. But making the rail move just for this seems inefficient.

One way it could be done that might be 'cleaner' is.. imagine if the chair rail were allowed to move left to right and were simply spring mounted to force it against the mirror frame. That way, as the mirror moved out, the chair rail would automatically push out as well, sliding into the vertical column, and being mounted to the fixed portion of the wall.

I love this thread!

Here are some screenshots I've made watching the effect. Look that green line due to the door reflections on the right.