I am BEYOND confused by this. What is it? Can you provide more context?
I think it is supposed to be a cutting pattern for the corners joint of bumpers.
Speaking as someone who reads and uses pattern drawings to sew, I don’t get it either.
It’s a pattern for the cloth cover to go over a mitered corner of standard FRC bumpers. The left side goes on a fold. The other heavy black lines are cut lines. The length will vary based on the length of a side; the dashed line indicates the end of the wood. The stitching goes along the gray line. I posted in response to post#2 in this thread. The two lengths are given since there is no scale on an image.
That looks familiar. It’s very similar to the pattern for the parts of team 192’s bumpers from '13 and '14. We had reversible bumpers with sewn mitered corners. In '14 the cloth was a single loop that fit snuggly over the bumper wood and foam.
Here are some pictures of the making of a example corner of the bumper fabric, as well as a close up corner of '14 bumpers and '13 and '14 bumpers on their respective robots. (Might want to start from the bottom photo)
Pre-sewn corner bumpers are available through robopromo.com. No cutting or sewing necessary. Here’s a helpful video that that shows you how simple it is!
There’s also a corner bumper cover that we offer for quick color change. Here is the link to that video: