Cause Exploration of Accuracy Deterioration with Time Progress in Localization Using a Speckle Odometer

A speckle odometer has been developed for estimating the self-position of a mobile robot. However, the speckle odometer suffers from the accuracy deterioration of measured values when it is used for a long time. One of the causes for this deterioration is known to be the temperature change in the odometer, but it is unclear which part of the device is responsible for such a change. The objective of this research is to investigate the relationship between the temperature and the measurement error and to reduce the distance measurement error by providing a temperature compensation. Therefore, a device using an NTC thermistor as a temperature sensor is manufactured in this research to measure the temperature of the speckle odometer. Furthermore, such a device is added to the speckle odometer to record the temperature changes during the travel measurement. From the recorded data, the relationship between the temperature and the measurement error is examined, and the places that affected the errors in the measured travel are clarified.