Hideo Kumagai

Development of a dual-axis thermal convective gas gyroscope

This paper presents the development of a dual-axis gas gyroscope, whose working principle is based on the convective heat transfer and thermoresistive effect of lightly doped silicon. The working principle and the cross-sensitivity of the gas gyroscope are also analyzed. Experiments were performed to confirm the simulation results and good agreement has been achieved. The measured sensitivities for the X-axis and Y-axis were 0.107 mV deg−1 s−1 and 0.102 mV deg−1 s−1, respectively. Compared with a gyroscope of the same configuration but using tungsten as a sensing element, this gyroscope has 42 times greater sensitivity and one quarter the power consumption. These advantageous characteristics are inherited from the high TCR and high resistance of lightly doped p-type silicon. Nonlinearity and cross-sensitivity were measured to be smaller than 0.07% FS and 0.5% FS, respectively. The effect of acceleration on the sensitivity is 0.02 (deg s−1)/g and the measurement resolution based on sensitivity and noise analyses is 0.05 deg s−1. The relations between sensor performance, power consumption and ambient temperature were also realized.

A dual axis thermal convective silicon gyroscope

This paper presents the design, simulation and fabrication of a semiconductor gas gyroscope. The proposed sensor can detect dual axis of angular rate. The gyroscope configuration consists of two main parts, the piezoelectric pump and the micro sensing part, which consists of four thermistor wires with dimension of 400 /spl times/ 4 /spl times/ 2 /spl mu/m/sup 3/, (length /spl times/ width /spl times/ thickness). Good agreement between the sensitivity simulation results and the experimental data has been realized. This gas gyroscope is expected to be applied in ship anti-rolling and stabilization systems.

A dual axis gas gyroscope utilizing low-doped silicon thermistor

This paper presents the design, simulation and fabrication of a dual axis semiconductor gas gyroscope. The sensor configuration consists of a piezoelectric pump and a micro thermal sensing element, packaged in an aluminum case with diameter and length of 14mm and 25mm, respectively. Good agreement between the sensitivity simulation results and the experimental data has been realized. This sensor is to be applied in ship anti-rolling and stabilization systems.

Development of a Dual Axis Convective Gyroscope with Embedded Heater and Low Thermal-stress Thermistors

In this paper, we present a novel structure of the sensing element or thermistor for the gas gyroscope. The thermistor is heated by a heater core, which is power -supplied independently. This design allows low voltage on the thermistor so that the noise on output voltage is reduced. Both heater and thermistor are optimized in order to reduce the thermal induced stress which occurred in the old thermistors at its working temperatures. The effect of thermal stress appeared in a p-type silicon thermistors reducing the performance of sensor by 7.5%, which is calculated and confirmed by directly measuring relative change of the resistance of the thermistor. A circular flow inside the hermetic case is simulated in detail by utilizing 3D transient compressible flow with the interaction of fluid-solid phase. The working principle and the effect of the jet-pump integrated inside the sensor are explained and validated by experiments using anemometry technique.

Optimization and characterizations of the dual axis gas gyroscope

This paper presents the optimization of the sensing element and characterizations of the dual axis gas gyroscope. Six different design of the sensing element were simulated to obtain higher sensitivity with lower power consumption. The influence of the arms structure to the thermal distribution along the thermistor was clarified. The working principle and the cross-sensitivity of the gas gyroscope are also analyzed. Experiments were performed to confirm the simulation results and good agreement has been realized. The sensor is expected to be applied in ship anti-rolling and stabilization systems

A dual axis silicon gyroscope based on thermal convective effect [ship applications]

This paper presents the design, simulation and fabrication of a dual axis semiconductor gas gyroscope. The sensor configuration consists of a piezoelectric pump and a micro thermal sensing element, packaged in an aluminum case with diameter and length of 14 mm and 25 mm, respectively. Good agreement between the sensitivity simulation results and the experimental data has been realized. This sensor is to be applied in ship anti-rolling and stabilization systems.