ot---SpinLaunch

pretty neat concept, curious to see how it works out and how they control the navigation of the projectile/payload.

I dunno, The whole thing sound like a sucker play, to get money from folks that have no real idea how much load is going to be applied (pretty much instantly) to the main bearings when that balanced arm drops it's 400KG mass on launch.
Doing some pretty basic math comes up with some really big numbers for the rotational speeds required, and anyone that doubts that it is likely to register on the Richter scale, ought to borrow a couple extra wheel weights and install them on one side of their tire, before they drive to work.
Used to be one of the 'evil prick' tricks to play was to stick a padlock through the U-joint on a fella's truck, to limit his speed going home...

Short of ejecting an equal mass out the back side of the launcher, with all the attendant problems of bleeding off the energy, I cannot see the launcher doing nearly what they propose.