Now, Sometimes these things that I make I make because I had a really, really quick idea brought on by something I saw out in the wild. This is one of them. I was stuck behind an 18-wheeler in a construction zone, and this trailer belonged to a company that made or sold garage doors. I thought, “Hey! There’s another logo I could kinda make up for no reason in particular!” Thankfully no one is paying me to make this.

The trick, though, was to get the motion of the garage door down pat. Garage doors are made up of long panels which are bolted to one another with hinges, and as they travel along an arched track, they follow one another like roller-coaster cars. This render isn’t perfect in its motion, but if you’re not paying close enough attention, it’s not too bad.

Relevant Websites

Nothing, this time.

Relevant Resources

Everything is 100% After Effects, and it shows.

Technical Details

The first step was to figure out the best way to organize the project. There are three rows, and each row has three panels. So I started with a single shape layer and drew out a red rectangle. I duplicated this twice and used the align tools to get their spacing equal. I also centered their individual anchor points inside the rectangle. Shape layers are weird in that the anchor of the layer stays in the center of the canvas, but the shape itself has its own anchor which is centered in the shape. This is a setting in preferences and is not the default behavior. I didn’t need to center the anchors, but I felt better about doing it. The last step here was to group these three layers into a “row” precomp.

Contents of the row precomp.

With the precomp on the main canvas, I did have to move the anchor because the three rows I needed each had to be 3D in order to be rotated the way a garage door panel would. The anchor, then, needed to be placed at about 98% of the way at the top of each row.

The wheels at the ends of each row of a garage door panel are attached to the hinges which connect the rows to one another. That means that “bend” of the garage door happens roughly at the top of each row.

Once the bottom row precomp was set to 3D, the row was moved to it’s final position at the bottom of the canvas. At 4 seconds, I added keyframes for Position and Orientation. Scrubbing back to 0 seconds, I moved the row up on the Y axis, and back on the Z axis. The panels move from the interior of the garage forward, and when they reach the arc of the track, begin to rotate. This was handled by setting the Orientation to 270 degrees on the X axis. Finally, I changed the Position motion path from a straight line to an arc. Because this was the first row panel, I had to make the downward traversal longer than the horizontal in order to accommodate the second and third rows.

I duplicated the bottom row to make the middle row. This one required some relative finessing because as it was it followed the bottom row’s motion exactly. I needed this middle row to stop above the first row, so I changed the final position to where it needed to be. Unfortunately this screwed up my timing and the relative positions of the rows. The solution was to scrub back to 0 seconds and pull the middle row back along the Z axis. Ideally the distance traveled by each of the rows would be the same, and they would need to follow the same arc, but the bottom panel needs a longer vertical traversal, the middle needs a balanced vertical/horizontal traversal, and the top and final panel would need a longer horizontal traversal. I had to work with the bezier handles to get the arcs to conform to one another after creating the top panel and moving it even further back along the Z axis.

Bottom panel’s Position path. Note the longer vertical traversal.
Middle panel’s Position path. Here, the traversals are balanced.
Top panel’s Position path. This time, the horizontal traversal is the longest.

With some keyframe tweaking to get the timing correct, and some futzing with Orientation values as each panel moved, I managed to get a fairly OK moving garage door. The resulting Scale and Position change to the door, and the text, were added just because I felt I needed to do something with animation, even if it was pretty lame in the end.

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