Initial Integration of UWB and GNSS Positioning Systems on a Nano UAV

Abstract

Precise and reliable localization is a fundamental requirement for autonomous unmanned aerial vehicle (UAV) operations, particularly during the landing phase, where positioning errors can lead to mission failure or UAV damage. This paper presents the integration of an ultra-wideband (UWB) positioning system and a global navigation satellite system (GNSS) receiver on a Crazyflie 2.1+ nano UAV platform. The GNSS module, a u-blox SAM-M10Q, was integrated onto the UAV, and a custom firmware driver was developed to enable logging of GNSS measurements as variables accessible to the Bitcraze client software. An experimental evaluation was conducted using four UWB anchors deployed around a designated landing zone to simulate a precision landing scenario. Position measurements from both sensors were collected at multiple altitudes during a simulated descent and compared against a local ground truth established by the UWB anchor geometry. Results demonstrate that UWB provides significantly more accurate and consistent positioning than GNSS during the final approach phase, motivating the development of a sensor fusion strategy for future work.