Shai, Offer

Read here about Offer Shai, a tensegrity researcher at Tel-Aviv University, Israel.

Overview

Offer Shai was a professor on the Faculty of Engineering, Tel-Aviv University, Ramat Aviv, Israel. His work focused on deployable, folding tensegrity structures.

Partial list of Tensegrity-Related Publications

Partial list of Tensegrity-Related Publications by Shai

• Recski A. and Shai O., "Tensegrity Frameworks in the One-Dimensional Space", will appear in European Journal of Combinatorics, 2010.

• Recski A. and Shai O., "One-Dimensional Synthesis of Graphs as Tensegrity Frameworks", 4th Japanese-Hungarian Symposium on Discrete Mathematics and Its Applications, June 3-6, 2005 in Budapest, Hungary.

• Recski A. and Shai O., "One-dimensional synthesis of graphs as tensegrity frameworks", 4th Japanese-Hungarian Symposium on Discrete Mathematics and its Applications, 2005, 284-288, Budapest.

• Recski A. and Shai. O., "One dimensional Synthesis of Graphs as Tensegrity Frameworks", ESI- Program 2006: Rigidity and Flexibility, April 23 – May 6, in The International E. Schrödinger Institute for Mathematical Physics, Vienna, Austria, 2006.

• Shai O., Tehori I., Bronfeld A., Slavutin M. and Ben-Hanan U., “Adjustable Tensegrity Robot based on Assur Graph Principle”, ASME International Mechanical Engineering Congress and Exposition, November 13-19, Lake Buena Vista, Florida, 2009, USA.

• Shai O., Orki O., Slavutin M., Ben-Hanan U. and Tehori I., "Employing Assur Tensegrity Structures Methods for simulating a Caterpillar Locomotion", Proceedings of the ASME International Design Engineering Technical Conferences & Computers and Information in Engineering Connference, August 15-18, 2010, Montreal, Quebec, Canada.

Selected Videos

Deployable Tensegrity Mast

In 2009 Shai's team published text and video on a deployable tensegrity mast. In the video below, Shai lectures on the theory behind the deployable mast.

In the videos below, the mast deploys and maneuvers.

3x4 strut mast with pneumatic struts, folding and unfolding

In this video a 3x4 unfolding mast, with pneumatic struts, is telescoped and folded back up. Shai explains some of the principles involved. The mast portion was filmed in 2006.

3x2 strut mast with pneumatic struts, folding and unfolding

This video has a 3x2 mast with detailed slides, videos and close-ups.

Selected Readings

Selected readings on tensegrity related topics by Shai and his students.

Adjustable Tensegrity Robot

Adjustable Tensegrity Robot Based on Assur Graph Principle by Shai, Tehori, Bronfeld, Slavutin, Ben-Hanan Link: http://www.scribd.com/doc/35190328/Adjustable-Tensegrity-Robot-Based-on-Assur-Graph-Principle-by-Shai-Tehori-Bronfeld-Slavutin-Ben-Hanan

A tensegrity robot is proposed and built of cables and actuators, based on the Assur Truss. The main idea of the control system of the device, that was also mathematically proved, is that changing the length of only one element, causes the robot to be at the singular position. Therefore, the system measures the force in only one cable, and its length is modified accordingly by the control system.

One-Dimensional Synthesis of Graphs

One-Dimensional Synthesis of Graphs as Tensegrity Frameworks by Recski, Shai Link: http://www.scribd.com/doc/29350951/One-Dimensional-Synthesis-of-Graphs-as-Tensegrity-Frameworks-by-Recski-Shai

Tensegrity structures are pin-connected frameworks where some of the members are cables or struts. Today, tensegrity structures interest researchers in engineering, mathematical and biological communities. The edge set of a graph G is partitioned into two subsets EC[ES. A tensegrity framework with underlying graph G and with cables for EC and struts for ES is proved to be rigidly embedable into a 1-dimensional line if and only if G is 2-edge-connected and every 2-vertex-connected component of G intersects both EC and ES. Polynomial algorithms are given to find an embedding of such graphs and to check the rigidity of a given 1-dimensional embedding.

Links and References

Deployable tensegrity mast project page: http://www.eng.tau.ac.il/~shai/dtm/dtm.html

The home page of Offer Shai's department is at http://www.eng.tau.ac.il/~shai/. Don't miss the video at http://www.youtube.com/watch?v=7R-EJAyC-V8, or see Itay's videos on http://www.youtube.com/user/itayteho.