Prof. dr Dubravka Mijuca

To Foster Credible and Reliable Implementation of Computational Mechanics in Industry

Finite Element Analysis of Tensegrity Structures

Tensegrity Framework Definition:

Tensegrity is an ordered finite collection of points in Euclidean space, called a configuration, with certain pairs of these points, called cables constrained not to get further apart; and certain pairs of these points, called struts constrained not to get closer together.

Tensegrity Structures belong to the class of the deployable structures technologies, used for booms, solar arrays and antennas on spacecraft; for portable shelters and retractable roofs; and for kinetic exhibition displays. In the past, these technologies have been developed by trial and error and for specific applications, but the current growing demand for deployable structures requires a new approach, as for example is the analysis with finite element approach.

Today's engineers, who already have Kevlar cords stronger than steel, will soon use concrete springs to absorb crashes, erect glass walls stronger than solid aluminum, and work with nickel-titanium sheets that can fold up and unfold by themselves on command, and rigid protective coverings that can heal themselves when fractured. The new model of efficient structures will incorporate materials that erect, mechanically service, maintain, and repair themselves.

On the next picture the deflection of the (6,24,3,3) tensegrity octahedron modeled by cables and beams finite elements, can be seen (Mijuca, 2002):

the model problem is analysed in STRAUS Finite Element software package

Click to download "gif" file with the vibrations of the first four mode shapes of the above model problem.

Click to download "gif" file with the deflection vs. frequency.

Click to download "gif" file with the animation file for the frequency with maximal deflections.

05 Nov 2009