Measuring system for avalanche research in Davos Scientists at the Federal Institute for Snow and Avalanche Research in Davos (Switzerland) wanted to record the course of avalanches as they race downhill and to measure the forces exerted when they impact with obstacles. For this purpose, a test zone measuring more than 2.5 km was established in the Valléee de la Sionne in collaboration with Mettler & Fuchs. Various structures were erected in the middle of the avalanche path, including various masts, a steel wall and a gallery roof. These structures were equipped with Kistler sensors for measuring forces and velocities. The object is to use the data from field tests to check the validity of the theoretical guidelines and to calibrate and improve the computer programs used to calculate dry snow and dense flow avalanches. Scientists from France, Spain and Austria are already using this spectacular system for their own experiments. Study into muscular atrophy Patients who are bedridden for a lengthy period suffer considerable muscular atrophy. This problem is even more pronounced in astronauts who spend a long time in weightless conditions. The Zurich Polytechnic laboratory for biomechanics directed by Professor Stüssi has investigated these conditions in a large project. The Torque Velocity Dynamometer (TVD) was developed in a very short time in collaboration with the European Space Agency (ESA), Kistler and other partners. This compact high-performance instrument for training and measuring enabled astronauts to carry out a selective analysis of the atrophy of various muscles in weightless conditions. Once again, Kistler sensors displayed their enormous loading capacity in the most confined space. The results of the study should help, on the one hand, to reduce muscular atrophy in bedridden patients and, on the other hand, to allow longer manned space flights. Measuring vibration forces The main drive system of satellite launch vehicles produces heavy vibration during the launch phase. To ensure that the satellite remains undamaged while being transported into space, pre-flight simulations are carried out on the satellite or its individual components. Vibration tests are of particular importance. The components are tested for their suitability on a vibrating table. If a component vibrates at its natural frequency, there is a danger that it will be destroyed. The standard procedure today is to monitor and check vibration forces with accelerometer in combination with a 3-component force-measuring device, in order to measure the reaction forces on the component simultaneously. To this end, a large number of 3-component force sensors are mounted on the test object or special dynamometers are employed as well. If the component vibrates at its natural frequency during the vibration test, vibration forces increase rapidly. These forces are limited by damping (notching) individual frequency ranges of the stimulation. This procedure is generally referred to as "force limited vibration testing". Wheel bearing forces Special version for measuring forces at wheel bearings of street cars, locomotives and trams. TVD (Torque Velocity Dynamometer) TVD with foot HIF (human interface) for measuring muscular atrophy. Measurement of vibration forces Space satellites and their components are subjected to vibration testing. Vibration forces are measured with a special multi-component dynamometer. The force measurement monitors the vibration process. www.kistler.com 33