The Xiaomi Mijia Mi Sphere is a great 360 degree spherical panorama camera. The companion selfie stick is very handy but it doesn't have a threaded insert to attach it to a tripod. This thing fits on the bottom after carefully removing the end cap (roll the rubber cover down and unscrew the two screws). A 3/8-16 nut is needed to complete this thing.
With this adapter, I can now use the Manfrotto 209 Table Top Tripod (without Head) to take 360 panos without holding the camera. If you have a tripod with a 1/4-20 thread, you can use an readily available 3/8" to 1/4" tripod thread adapter.
I used 8 perimeter shells and 4 layers on top and bottom to strengthen the flange.
Bolt the nut in the cavity with epoxy or superglue.
Fusion 360 and Simplify3D