Geometric mobiles: From conceptualization of motion in space to rational design

The author uses geometrically definable shapes for mobile members in such a way that equations can be written for moment balance to yield analytical s olutions for determining the suspension points of the members. This avoids the need for trial-and-error construction. Geometrically definable shapes a lso make it possible to use jigsaw layout of mobile members to minimize was te of materials. The author finds that these two "constraints" add an intel lectual dimension to mobile-making. To facilitate the realization of a mobi le maker's conceptualization of shape and motion in space, the author recom mends small indoor mobiles, which can be made to respond to weak air curren ts such as those produced by body movement and human breath.