The relationships between piezoelectric characteristics of a ceramic cylindrical resonator and the performances of a vibratory gyroscope such as sensitivity and zero offset were assessed by an equivalent circuit model. It was confirmed that the temperature stabilities of the gyroscope performances depend on temperature variations of mechanical quality factor (Qm), damped capacitance (Cd) and resonant frequency (fr).The piezoelectric characteristics were investigated in the ternary system of PbTiO_3-PbZrO_3-Pb(Mn_(1/3)Sb_(2/3))O_3, and reduction of Pb (Mn_(1/3)Sb_(2/3)) OS proportion less than 5 mol percent and addition of Sm_2O_3, Fe_2O_3 and MnO improved the temperature stabilities of Qm, Cd and fr. Consequently a material having temperature variation ranges of Qm, Cd and fr within + 12 percent approx -29 percent, +16 percent approx -9 percent and +0.2 percent approx -1.1 percent respectively at -30 deg C approx +80 deg C was obtained.Finally, a gyroscope having a temperature variation range of sensitivity within +- 10 percent and that of zero offset within +-10 deg /s was obtained, which is applicable to direction sensors of car navigation systems.
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