The gravity simulator helps students visualize how massive objects warp the fabric of space-time.
Our gravity simulator is consists of a rigid rebar and PVC skeleton and a spandex surface. The PVC skeleton (as shown in the pictures) is attached to a ring of rebar inside a common garden hose to provide a frame for the spandex.
The spandex is stretched evenly across the ring. Once an even surface is created, a weight of one to five kilograms is set in the center of the spandex, creating a cone-shaped gravity gradient. Any round object will be inclined to roll toward the weight in the center. This attractive force, when combined with a motion tangent to the ring, will result in the round object orbiting the weight in the center, thus simulating a gravity field like that of a solar system.
Multiple round objects can be added to the surface—they will exert a gravitational force on each another. This can result in complicated motions. For example, two marbles can orbit each other while simultaneously orbiting the center weight.
Credit for the idea: