Using zero velocity updates to improve the dead-reckoning performance of a planetary wheeled robot.

What is it about?

In this study, we focus on improving the navigational performance of the blind-driving (a dead-reckoning model used in Mars rovers) mode. In other means, if the blind-driving mode can be improved, computationally expensive visual-based methods will be used less often, and the rover can travel more and faster. We attempted to improve it by leveraging the use of zero-type constraint equations in the navigation filter. In order to use the zero-updates, the rover needs to stop. But fortunately, the planetary rovers are often in the stopping conditions for several reasons. When the rover stops or commanded to stop, the IMU can sense this action and can be used as a pseudo-measurement. This measurement update enhances the navigation solution.

Featured Image

Photo by Dominik Scythe on Unsplash

Photo by Dominik Scythe on Unsplash

Why is it important?

This work presents several strategies for enhancing the accuracy of wheeled planetary rover navigation. When using all of the presented update strategies together, the proposed approach was demonstrated to significantly reduce the rate of the rover localization error growth. Besides, we showed that slippage could be detected by using a threshold on the velocity residuals and the slip ratio estimate. The primary value of this approach is that it can be used within current and future planetary rovers, as well as many other wheeled robots that frequently stop, to improve onboard localization performance without any hardware changes or major alterations in operations.

Perspectives