Precision-Calibration of Fiber-Optics Gyroscopes for Mobile Robot Navigation

Fiber-optics gyroscopes (“gyros”) are gaining importance as a means for improving dead-reckoning accuracy in mobile robots. In the past, the relatively high drift rate of moderately priced gyros presented the foremost technical limitation of these devices. More recently, fiber-optics gyros with very low drift rates have become available and affordable. Because of their low drift rate attention is warranted to sources of errors that were previously considered as of secondary importance. In the KVH E-Core RD2100 gyros that were examined at our lab we found that the non-linearity of the scale-factor and temperature dependency caused significant errors. A calibration method, described in this paper, reduces the resulting errors by one order of magnitude.