If you have some warning about rain when commuting to your job or class, you might wear a jacket, or keep your umbrella at the ready. For storms that come up all of a sudden, Emiel, “The Practical Engineer” has a novel solution — an umbrella that pops up in an instant after pulling its ripcord.
The design is built around a small backpack, which conceals a shaped piece of wood that holds the mechanical bits. Mechanics include a pair of springs, as well as some fairly heavy bearings and an axle, that flip the umbrella on an external pivoting arm up and over the user. A pneumatic valve is also connected to the assembly not to power it, but to keep its speed under control.
A pin normally holds the umbrella down, attached to a cord that the Emiel can pull to release when needed for rain protection — or perhaps heat relief during a hot summer day. Parts for the project are cut on a band saw and lathe, and 3D-printed, but one of the more unique techniques used is shown around 4:30 in the video below where he loops a cord into itself to form a sort of slipknot.