Extremely Sensitive Tension Sensor

• EXTREME PARAMETER: Project with Our Smallest Participation
• ACTIVITY AREA: Research and Development
• INDUSTRY SECTOR: Research and Development
• CLIENT: Institute of Physics, Slovak Academy of Sciences
• PROJECT LEADER: Ing. Vladislav Valent

Since all of us ANDIS partners are originally the employees of today´s FEI STU college, we have never been avoiding science and technology projects. On the contrary – each return to the academic ground was a welcome change of our life rhythm, the opportunity to refresh old memories and, at the same time, the source of new information and a challenge to do something „special“.

This case was not different. The project was initiated by the Institute of Physics, Slovak Academy of Sciences and we were invited to cooperate because of our openness towards the academic world, in which the laws of physics are still valid even today.

The whole project was running for several years, we only had the opportunity to cooperate with this top-notch science institution during its final part. For long years, the employees of the Slovak Academy of Sciences were developing a special magnetic material, which, thanks to its properties, was opening truly unseen horizons for new technical applications. Everyone who has been working in the basic research, in any science sector, knows how difficult it is to invent something nobody had invented before and, on top of that, find a useful practical application for this precious theoretical result.

The Institute of Physics of Slovak Academy of Sciences succeeded in doing that. The magnetic material mentioned above truly had unique properties and the scientists from SAV not only were able to discover these properties and describe them by formulas, but also to use them in the praxis. They designed a tension sensor with extreme sensitivity. The target was very ambitious – a 10cm long sensor, bolted to a tunnel or bridge construction pillar, should register microshifts caused by the movements of the upper part of the earth crust, aging of the concrete pillar or fatigue of the gigantic iron construction. The long term measurement and evaluation of the microshifts would enable the monitoring of the „development“ of these inanimate giants, to reveal hidden technical flaws and to prevent from possible consequences.

To illustrate the sensitivity of such a sensor, imagine the following: an iron bar is fixed in a horizontal position to a table with a clamp on one end. The bar has a cross section of 1x5 cm and the length of let´s say 20 cm. The tension sensor along with an electronic evaluation system is attached to the side of the bar. Should you place a common paper business card on the loose end of the iron bar, do you know what would happen? That´s clear! The iron bar would bend under the weight of the business card! Would you notice that? Not a chance! The tension sensor would! Not only that, it would also measure the amount of tension produced by the business card.

We took part in this project and contributed a little to its realization. But the admiration goes to the employees of the Slovak Academy of Sciences – to see a business card bending an iron bar, that truly was an impressive experience.

Technical information about the project