Jansen Strandbeest

Theo Jansen’s walking machine

Theo Jansen builds amazing walking machines.
Each leg is an eight-bar linkage. The Wolfram Demonstration Project models this linkage in a Mathematica notebook. See the link:




Periodic Table

NIST Periodic Table

Periodic Table

Periodic Table

The National Institute of Standards and Technology provides an on-line periodic table. Access it and other information at the link:  Periodic Table

National Institute of Standards and Technology

National Institute of Standards and Technology

Geometric Dimensioning and Tolerancing

This is a link to notes on Geometric Design and Tolerancing by Prof. Graeme Britton of Raffles Design Institute, Singapore.

Prof. Britton's Notes on GD&T

Prof. Britton\’s Notes on GD&T

A pdf version of Prof. Britton’s lecture is available at:

Here is another excellent set of notes from the Technical College of New Jersey on geometric dimensioning and tolerancing.