Question

Displacement h The attached Figure shows a capacitive-displacement sensor designed to monitor small changes in work-piece position. The two metal cylinders are separated by a plastic sheath/bearing of thickness 1 mm and dielectric constant at 1 kHz of 2.5. If the radius is 3 cm, find the sensitivity in pF/m as the upper cylinder slides in and out of the lower cylinder. (€=8.854188 x 10-12 F/m; c= FOE7A,

Answer 1

solution. This question is gelated with the subject mechatronics. Plate sepasation thickness, d= 1 mm Diclatsic constant , k = 2.5 Radius 10 m. 2 R = 3cm = 3x10 m peomitivity, I E = 8,854188 x16 !? Fim PF/m. Shared cylindrical area = 8.85 Plate Common area = А A = 27Rh Capacitance, c = KEA d. KE 27Rh d on Keo Rh by - sensitivity with respect to the height, h is defined c changes with hi how dc dh = 25k ER DAKE d 2 = 27 X 2.5% 8.85 X 3x16 -3 lo = 4170.46 PF/m. Hence, sensitivity = 4170 46 Pflm