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A high-accuracy differential resonant pressure sensor with two similar resonators is proposed using the linear fitting method to guarantee its output linearity without polynomial compensation. Results reveal that the nonlinearity of the differential resonant pressure sensor is largely dependent on the tensile/compressive sensor pressure–stress ratio c when two similar resonators are used separately as compressive and tensile elements. Nonlinearity decreases sharply with an appropriate ratio c. A theoretical model is proposed to obtain minimal nonlinearity and shows satisfactory agreement with the simulation results. The impact factors of ratio c are analyzed to facilitate adjustments with the designed value. Moreover, micromachining methods are used to fabricate sensing chips. Experiment results show that the nonlinearity and measurement sensitivity of the proposed differential resonant pressure sensor are ±0.02% FS and 35.5 Hz kPa−1 with the linear fitting method in a pressure range of 0–200 kPaA and temperature range of −40 °C to +40 °C. The differential linear fitting method largely decreases compensation complexity without polynomial fitting for high-precision pressure measurement.

Simulation mathematical model of maneuverability such as zig-zag and turning circle test under different rudder and speed is built and the rudder rotary response effect on ship maneuverability parameters is analyzed extensively. In the paper, MMG (maneuvering model group) model is adopted to set up the 3 degrees of freedom governing equations of ships, in which the rudder rotary response is approximated by the assumption of uniform rotary speed. A sea-going vessel of 10 thousand deadweight tonnages is selected as the numerical simulation target to investigate the rudder rotary response effect on ship maneuverability parameters, such as the zig-zag and turning circle test. Some meaningful conclusions are concluded through comparative analysis, the conclusions indicate that rudder rotary response has remarkable effect on ship maneuverability, and it is a significant factor which needs to be taken into consideration for actual ships.