3D Indoor Positioning of UAVs with Spread Spectrum Ultrasound and Time-of-Flight Cameras

• Main Authors: José A. Paredes, Fernando J. Álvarez, Teodoro Aguilera, José M. Villadangos
• Format: Article
• Language: English
• Published: MDPI AG 2017-12-01
• Series: Sensors
• Subjects: acoustic positioning system (APS); unmanned aerial vehicles (UAV); time-code division multiple access (T-CDMA)
• Online Access: https://www.mdpi.com/1424-8220/18/1/89

This work proposes the use of a hybrid acoustic and optical indoor positioning system for the accurate 3D positioning of Unmanned Aerial Vehicles (UAVs). The acoustic module of this system is based on a Time-Code Division Multiple Access (T-CDMA) scheme, where the sequential emission of five spread spectrum ultrasonic codes is performed to compute the horizontal vehicle position following a 2D multilateration procedure. The optical module is based on a Time-Of-Flight (TOF) camera that provides an initial estimation for the vehicle height. A recursive algorithm programmed on an external computer is then proposed to refine the estimated position. Experimental results show that the proposed system can increase the accuracy of a solely acoustic system by 70–80% in terms of positioning mean square error.