Hoberman Sphere: http://physicstoys.blogspot.com/p/physics-toy-store.html Isokinetic structure. This special assembly of fold-able linkages consisting of rigid bars and simple hinges is kinematically over constrained- motion can only occur along the radial direction and the movement of any hinge creates motion in all the joints. The engineering and physics behind deploy-able space structures! ➡️ Follow the link above for info on where to get this and other amazing items featured here on Physicsf

When you spin a fully expanded Hoberman Sphere, it rotates slowly. But if you collapse it mid-spin, the rotation speeds up dramatically. First we need to know that momentum measures how difficult it is to stop a moving object and it depends on the object's mass and velocity: ▪︎ Linear momentum refers to straight line motion (a tennis ball is easier to stop than a bowling ball). ▪︎ Angular momentum applies to spinning objects and depends on mass and angular velocity (a coin flip is easier to stop

Hoberman Actuator with Sphere https://www.physicsfunshop.com/search?keywords=hoberman This actuator mechanism creates kinetic art out of a Hoberman sphere, designed to smoothly expand and contract the isokinentic structure. The Hoberman sphere itself is a special assembly of foldable linkages consisting of rigid bars and simple hinges is kinematically over constrained- motion can only occur along the radial direction and the movement of any hinge creates motion in all the joints. The engineering

When you spin a fully expanded Hoberman Sphere, it rotates slowly. But if you collapse it mid-spin, the rotation speeds up dramatically. First we need to know that momentum measures how difficult it is to stop a moving object and it depends on the object's mass and velocity: ▪︎ Linear momentum refers to straight line motion (a tennis ball is easier to stop than a bowling ball). ▪︎ Angular momentum applies to spinning objects and depends on mass and angular velocity (a coin flip is easier to stop