Patent ID: 9683849
Date: 2017-06-20
CPC Classifications: G01C,G01S

Claim:
1. A method for improving the accuracy of a vehicle navigation module including a gyroscope and a navigation filter, the method comprising: storing average gyroscope biases as a function of temperature, the average gyroscope biases as a function of temperature obtained by averaging gyroscope biases over a plurality of temperature cycles; computing gradients of gyroscope bias as a function of temperature from the average gyroscope biases as a function of temperature; estimating a gyroscope bias at a first temperature based on a reference rotation rate when the reference rotation rate is available by: (i) measuring a rotation rate at the first temperature using the gyroscope, and (iii) comparing the measured rotation rate with the reference rotation rate; and, estimating a gyroscope bias at the first temperature, when no reference rotation rate is available, via linear extrapolation from a known bias value at a second temperature, the linear extrapolation taking into account a difference between the first temperature and the second temperature and a gradient of gyroscope bias at the second temperature from the computed gradients of gyroscope bias.