Here is the official explanation of what the Activity is, which can be found on the same page where builders should share their submissions:
Tensegrity has taken the LEGO world by storm over the past week and we would love to see what kind of fantastical “floating” creations you can make using the structural principle of tensegrity! To show us that your build actually works, you must build your creation using real LEGO bricks and include a short video showing your creation.
This is part of a series on LEGO Ideas that gives little tasks for builders to get involved with – there are no prizes, they are just a way to get involved with building something quick for fun. Each challenge is intended to be something quick and fun, unlike the more in-depth building required for a competition or product idea.
The deadline for this Activity is April 28 at 10.00am CEST.