Speaker
Description
For the years, seismic geophone production technology has monopolized to industrial countries and
developing countries were less engaged in this field. Recent scientific researches and extending of
exploration seismology in developing countries has persuade them to work on this important filed of
instrumental seismology as a base of safe and low cost instrument production.
As our case, we have taken great steps towards advance sensor technology and this paper presents
manufacturing and analysis of a novel, absolute velocity geophone. Main geophone parameters; resonant
frequency, magnetic flux of permanent magnet, and physical dimensions, were considered as inputs and
spring dimensions, spring stiffness, spurious frequency and the generator constant are obtained as outputs.
Applying professional ANSYS analysis; effects of variation in proof mass, spring design, and damping
constant of coils on frequency response to step and random vibration are studied.
Static stress analysis of springs in horizontal and vertical directions are calculated and results were used
optimizing output parameters. A geophone with frequency of 10Hz and proof mass of 10gr is designed
which its distinctive characteristic is having high spurious frequency of 460 Hz in comparison with
existing types. Finally the theoretical and simulations are compared to the real experimental data.
