| 摘要 |
A joint unit which provides a cluster of up to six ball-and-socket joints. The balls of the ball-and-socket joints are arranged as, or as part of, a substantially close-packed cluster, and a binder supports the balls in position and provides a socket for each ball. The joint unit provides multiple ball-and-socket joints concentrated into a small volume, and is useful for many different applications, but especially for making crystallographic, geometric or molecular models. |
