Field demonstration of a Mars navigation system utilizing GPS pseudolite transceivers

Tasks envisioned for future generation Mars rovers-sample collection, area survey, resource mining, habitat construction, etc.-will require enhanced navigational capabilities over the Mars Sojourner rover. Many of these tasks will involve cooperative efforts by multiple rovers and other agents, adding further requirements both for accuracy and commonality between users. This paper presents a new navigation system (a self-calibrating pseudolite array) that can provide centimeter-level, drift-free localization to multiple rovers within a local area by utilizing GPS-based transceivers deployed in a ground-based array. Such a system of localized beacons can replace or augment a system based on orbiting satellite transmitters, and is capable of fully autonomous operations and calibration. This paper describes the prototype SCPA that has been developed at Stanford to demonstrate these capabilities and then presents new results from the most recent set of field trials performed at NASA Ames Research Center. These experiments, which utilize the K9 Mars rover research platform, validate both the navigation and self-calibration capabilities of the system.