Hoberman sphere facts for kids
.jpg)
A Hoberman sphere is a special kind of structure invented by Chuck Hoberman. It looks a bit like a geodesic dome. What makes it unique is that it can fold up very small. Then, it can expand to become much larger! It does this using a clever scissor-like movement in its joints. You might have seen colorful plastic Hoberman spheres as toys. They can expand from about 15 cm (6 inches) to 76 cm (30 inches) wide.
Contents
How Hoberman Spheres Work
A Hoberman sphere is made up of many connected parts. These parts are usually arranged in six large circles. These circles are like the lines you might draw around a globe. The way these parts are connected allows the sphere to change size.
The Clever Design
The secret to the Hoberman sphere's movement is its special joints. Each joint works like a scissors mechanism. Think about how a folding chair opens and closes. When one part moves, all the other parts move too. This linked action lets the whole sphere expand or shrink smoothly. For very large Hoberman spheres, a string or cable can be used to help them open and close.
Giant Hoberman Spheres
Hoberman spheres aren't just toys. Some very large ones have been built for science centers around the world. These giant spheres show off the amazing engineering behind the design.
World's Largest Sphere
The biggest Hoberman sphere in the world is at the AHHAA Science Center. This center is located in Tartu, Estonia. When it is fully open, this sphere is about 5.9 meters (19 feet) wide. It weighs about 340 kilograms (750 pounds) and is made from strong aircraft-grade aluminum. This huge sphere is motorized. It constantly opens and closes in a programmed way. Its movements are set to music, lights, and special effects. It hangs above the Science Court at the center.
Other Large Spheres
Before the one in Estonia, a slightly smaller Hoberman sphere was built. You can find it in the main hall of the Liberty Science Center. This center is in Jersey City, New Jersey. This sphere weighs about 317 kilograms (700 pounds). When it is fully expanded, it measures about 5.5 meters (18 feet) across. Another large Hoberman sphere was put in place in 1993. This one is at the Swiss Science Center Technorama. It is located in Winterthur, Switzerland.
See also
- Scissors mechanism
- Geodesic dome
