Leonardo Da Vinci proposed a simple machine to trace an ellipse. Descartes discussed about the use of mathematical machines to solve geometry problems [1]. Another important use of linkages in geometry is due to Kempe [2] who proposed a mechanism for tracing straight lines. The usefulness of mathematical machines in the teaching of geometry is also witnessed by the works of Courant and Robins [4] and Cundy and Rollet [3]. Interesting work has been made available on the internet by the Italian Mathematical Machines Association [5]. In our presentation it will be discussed the experience of the authors for simulating with GeoGebra noteworthy mathematical linkages.
[1] Descartes, R., La Géométrie, A.Hermann, Librarie Scientifique, Paris, 1886, http://www. gutenberg.org/files/26400/26400-pdf.pdf
[2] Kempe, A.B., How to Draw a Straight Line-A Lecture on Linkages, 1877, http://www. gutenberg.org/files/25155/25155-pdf.pdf
[3] Martyn Cundy, H., Rollet, A.P., Mathematical Models, Tarquin Publications, 1989
[4] Courant, R., Robbins, H., What is Mathematics ?, Oxford University Press, 1969
[5] Associazione Macchine Matematiche (Mathematical Machines Society), Italy, http://www. macchinematematiche.org/