High precision multiple ultrasonic transducer positioning using a robust optimization approach

Ultrasonic positioning systems are used for various types of applications across a wide variety of fields, including robot navigation, device location and pose estimation. Current ultrasonic positioning systems have limitations when simultaneously locating multiple transmitters in three-dimensional (3D) space using narrowband ultrasonic transducers. They are also unable to calculate a transmitter´s position in 3D using traditional multilateration algorithms when receivers are positioned in a single plane. Recently, we developed a robust optimization algorithm for locating a single transmitter in 3D when all the receivers were positioned in a single plane which was shown to accurately locate a single transmitter with sub-millimetre accuracy. Here, we extend this algorithm to simultaneously locating multiple transmitters by compensating signal interference using narrowband orthogonal division multiplexing (OFDM) signals. Our experimental results show that the proposed system has the precision required for medical applications and is of lower cost and complexity than alternative traditional optical systems.