When the arms of a robot move to pick up an egg or an electric lamp, the greatest precision possible is essential. To this end, advances in the science and technology of materials have provided the design and control of systems equipped with sensors and actuators built with new materials.

The Automation Group at the Department of Electricity and Electronics of the Faculty of Science and Technology at the Leioa campus of the University of the Basque Country (UPV-EHU) is studying the stimulus-response characteristics of various kinds of materials to be used in the generation and measurement of precise movements in electromechanical systems in miniature and in robotics.

The studies focused on two types of materials in concrete, and which had promising characteristics for micropositionng applications: shape-memory alloys (SMA) and magnetic shape memory (MSM) alloys or ferromagnetic shape memory alloys (FSMA). All these smart alloys are new materials, catalogued as intelligent for their ability to memorise shape and other novel properties.

Shape-memory alloys are capable of remembering their original size and shape despite having undergone a deformation process. The most common alloy amongst these is that generically known as nitinol, given that it is made of almost 50% nickel and almost 50% titanium. It is on the market and is sold in the form of wire.

Magnetic shape memory alloys are ferromagnetic materials capable of withstanding large transformations that are reversible both in shape and size when a magnetic field is applied to them. They do not exist as yet commercially and are currently only made in research laboratories.

The team built a number of potentially useful devices for robotics, using these shape memory materials, and investigated new applications fundamentally aimed at light or miniaturised electromechanical systems.-Elhuyar Fundazioa