Previous post: Theoretical background of the Linear FCDT (https://hackaday.io/project/11225-a-new-high-accuracy-tilt-sensor/log/46957-theoretical-background-of-the-linear-fcdt)
In the previous post I showed how we can calculate Vsec1, and Vsec2 with respect to the tilt of the sensor. I also pointed to that the measuring range and the sensitivity of the Linear FCDT is strongly depend on the L/R ratio. (Where L and R are shown in the previous post"s first picture.)
In this post I'm going to compare the theoretical and experimental curves of our Linear FCDT.
Our Linear FCDT was tested with the AD598 signal conditioner IC, which is used with LVDTs. The coil length of the sensor was L = 18 mm; the radius of the inner cell was R = 3 mm; the amplitude of the excitation voltage was A = 6 V; the frequency was f = 11 kHz; the M cell constant was determined using the already known dimensions of the cell, and the extreme values of Uout:The theoretical curve was determined with the knowledge of the L/R = 6 rate, and the M cell constant: