# Tensegrity Powerto the People

 Tensegrities have been around for a long time, but not specifically referred to as such. Examples are the spokes, hub and rim of a bicycle wheel, a bow and arrow, a spider web, suspension bridges, . . . There are scholarly articles on the statics and dynamics of tensegrities. There are youtube videos purporting to show how to construct tensegrities with various numbers of struts and cables, there are books on how to construct them as well. In none of these sources did I yet see any reference to the way I make tensegrities. Admittedly, my way is more pedestrian than the other ways. My procedure is to build a jig out of wood, attach the struts to various faces of this jig, thus securing the struts in space relative to one another, though free to rotate. Next, the structure is stringed, meaning that strings are added, tying together the ends of various struts. If the structure is strung correctly, when the jig is removed, the strings are still tight, and we have a self-supporting tensegrity. There is no need to calculate in advance the lengths of the strings, because the ends of the struts they join are at a fixed distance from one another. If the structure is not strung correctly geometrically, when the jig is removed, the structure falls down and is not self supporting. Here is a set of photos from the first tensegrity workshop at TCNJ using the method of scaffolding. Thanks to Gabe Randazzo for the first six, and to David Sanchwez for the seventh. Photo 1 Photo 2 Photo 3 Photo 4 Photo 5 Photo 6 Photo 7 Robert Burkhardt has an interesting mathematical theory for constructing tensegrity domes, as well as a book on the statics of tensegrities using nonlinear programming. Robert Connelly and Allen Back have written a widely read article on the mathematics of tensegrities in The American Scientist. Also, Connelly and Whitely have started a serious study of the dynamics of tensegrities. Here is a small picture gallery of some of Kenneth Snelson's small sculptures Here is some of the literature on tensegrities Here is a 16-foot high bamboo tensegrity A nice collection of tensegrity images Some tensegrity sculpures by the sculptor William Collins. Here is a 2-part video of a talk I gave in Dorin Zeilberger's Experimental Math Seminar on April 4. 2013 part 1 part 2