I am honored by the invitation to give a lecture at this Conference on Vacuum Microbalance Techniques. I have very good memories
of such meetings over 35 years, first in the USA, and then alternating in Europe and Africa. Those who have participated in
several conferences of this series know that major developments from manually operated to automated balances have been presented
there and documented in the Proceedings of these Conferences. I would like to give a few examples from my own work.
Balances utilising the principle of free magnetic suspension can be very useful for thermogravimetric experiments, where aggressive atmospheres and high pressures are applied. Magnetic coupling systems with automatically controlled attraction can be used for direct conversion of weight into an electric signal or for the separation of object and beam balance. The magnetic suspension balance is described and a new versatile magnetic coupling system is presented. Due to its low weight, this coupling can be combined with a microbalance.
The paper gives a survey of the history of damping methods for balances. Representation on Egyptian drawings demonstrate that
the person performing the weighing shortened the measuring time by holding the suspension cords and touching the beam. By
means of delimiters, the Romans constricted the deflection amplitudes. In the 19th century, the movements of precision balances
were damped with a brush. For analytical balances, locking mechanism were developed, often combined with levers lifting the
weighing scales and the beam in order to relieve the knife-edges. Half-arresting was used to curtail weighings. Air damping
was invented by Arzberger in 1875, and eddy current damping by Marek in 1906. In electronic balances, lag, lead and filter
elements and absorptive attenuators are used. For digital balances, the fast-reacting nullification of eddy signals is applied.
Authors:Th. Gast, T. Brokate, E. Robens, Z. Ali, and K. Pavey
The influence of mass and force on the frequency of vibrating bodies today is widely applied. In Part I of the survey the historical roots are reviewed and the physical principles of the several arrangements modes of operation explained.
Authors:E. Robens, D. Möhlmann, R. Staudt, Th. Gast, and M. Eger
European and American Missions to Mars will be focussed on the search for
life, and of water, as a precondition for the existence of complex organisms.
Besides the polar ice caps of carbon dioxide and water, in the upper few meters
of the Martian surface, water and ice bound to the soil surface, is expected.
Therefore we propose to investigate the storing capability of Martian soil
in situ. This planned quite new type of investigation makes use for the first
time of a balance at a celestial body outside Earth.
Authors:E. Robens, D. Möhlmann, Th. Gast, R. Staudt, and M. Eger
The balance is the most widely used complex measuring instrument in
science and techniques. To install a balance on Mars is a challenge for numerous
aspects of in situ measurements in the next decade. By means of a balance
useful parameters could be determined and a variety of investigations could
be carried out there. Possible applications of a balance on Mars are reviewed.
Choice of type and demands on the balance with regard to the conditions on
Mars are discussed. The first step is to test a load cell with strain gauge