Patent ID: 6805009
Filing Date: 2004-10-19
Classification: G01M,G01N

Abstract:
A resonant sensor for determining structural property changes characterised by a structure (2) mounted to be capable of resonating, the structure (2) having a cyclically symmetrical configuration with two independent degenerative modes of vibration of a common natural frequency, and means (24,26,28,30,32,34,36,38) for exciting the structure (2) to resonate according to said two degenerate modes, regions (8,12,16,20) of the structure (2) being modified such that, on changes in the structural properties of the modified regions (8,12,16,20), the natural frequencies (f1,f2) of the two modes of vibration become different, the difference in frequencies (&Dgr;f) being proportional to the change in structural properties.