This hard to find sculpture curretnly available here:
From Amazon: Hyperbolic Kinetic Sculpture
Kinetic Traced Hyperboloid: a straight rod glides through a symmetric pair of curved holes in this kinetic sculpture based on the hyperboloid, the 3D ruled surface traced by an offset revolved straight line. This version is made of anodized aluminum and rotates via gearing and a motor powered by two AA batteries in the base.
From eBay: BUY NOW
Hyperboloid Spinner: HypnoGizmo
Hyperboloid Spinner: the HypnoGizmo toy consists of a set of slanted straight nylon lines arranged to form the outline of a hyperboliod- the quadratic surface related to the revolution of hyperbola around its axis of symmetry. As the device rotates the beads slide along in succession on one of the straight paths leading to the complex visual display. So much fun math in this toy!
Choose your color and get one here:
From Etsy: BUY NOW
Hyperboloid Pencil Holder
don't forget a set of pencils:
From Amazon: BUY NOW
Colored Pencil Sets
Better yet- get some thermochromic color changing pencils!
From Educational Innovations: BUY NOW
Pencil Hyperboloid: a perfect gift for any math teacher- the precisely oriented holes in this base direct 16 pencils to reveal a hyperboloid, the 3D surface traced by revolving a diagonal(skew) line, the outline of which is the conic section of the hyperbola. A doubly ruled surface for any desktop!
Visit the Exploratorium
This exhibit reminds me of an amazing geometric sculpture where I used to work: Tractricious by Robert Wilson, founding director of Fermi National Accelerator Lab
Click this link for inexpensive hyperboloids you can own!
String Hyperboloid @exploratorium : 26 strings held straight by hanging weights can be rotated as a set to produce a hyperboliod- the quadric surface related to the revolution of hyperbola around its axis of symmetry. Note that although this 3D shape is curved, an a infinite set of straight lines (like those of the strings) lie on its surface. Turning the top disk of this exhibit raises the weights on each string so that when it is released the potential energy will transfer back and forth to kinetic energy of rotation until the energy is damped out due to friction. ? With thanks to the Exploratorium!