无温度传感器的金属振动陀螺温度补偿

Temperature Compensation of the Metallic Vibratory Gyroscopes (MVG) without Temperature Sensors

关键词:  金属振动陀螺  温度系数  零偏漂移  温度补偿

Key words:  Metallic Vibratory Gyroscope  Temperature coefficient  Bias drift  Temperature compensation

摘要:

金属振动陀螺是一种低成本、长寿命的新型简并模谐振陀螺,其结构相对简单,加工相对容易实现。但是,金属材料的温度系数和热膨胀系数大,其受到温度变化的影响明显,温度漂移对器件最终性能的影响较为明显。因此,对金属振动陀螺进行温度补偿,可以显著提高器件性能指标。建立了金属振动陀螺的温度模型,确定环境温度对器件谐振频率和零位偏移的影响关系。研究发现,金属振动陀螺谐振频率的温度系数具有超高线性度,可以替代温度传感器的作用,直接用谐振频率作为温度补偿量的输入。基于温度模型,进一步建立了温度漂移补偿模型,计算金属振动陀螺谐振频率的温度系数和零位偏移的温度关系,并对金属振动陀螺的温度漂移进行补偿。通过实验结果验证,金属振动陀螺谐振频率的温度系数为0.0536 Hz/℃,线性度达3.4×10-6,零位偏移和温度呈二次曲线关系,温度补偿后,金属振动陀螺的随机漂移可降低65%左右。

Abstract:

The metallic vibratory gyroscope (MVG) is a novel degenerated mode resonant gyroscope with a low cost and long life, which has a simple structure and is accessible to machine. As the metal materials have a large temperature coefficient and thermal expansivity, the temperature has an evident effect on the bias drift of the devices. Thus, the temperature compensating of the MVG could improve the gyroscope's performance significantly. This paper finds a temperature model of the MVG, to establish the relationship between the resonator frequency, bias and the environment temperature. The model shows that the MVG has a quite high temperature coefficient linearity about the resonation frequency, which makes the resonation frequency could be inputted as a compensating value and replaces the temperature sensors. Based on the temperature model of the MVG, a temperature compensating model is built to calculate the temperature coefficient of the resonation frequency and the temperature sensitivity of the bias. Then, the bias drift of the MVG, caused by the temperature, is compensated. The experiment results show that the device has a temperature coefficient of the resonation frequency of 0.0536 Hz/℃, with a linearity of 3.4×10-6. The bias drift reaches a quadratic curve relationship with the temperature. This compensation method decreases the bias drift of the MVG by about 65%