SBIR Phase II: Ultrasonic 3D Rangefinding for Mobile Gesture Recognition

This Small Business Innovation Research (SBIR) Phase II project proposes the development of an ultralow-power ultrasonic three-dimensional (3D) rangefinder system for mobile gesture recognition. The proposed 3D rangefinder uses an array of tiny piezoelectric ultrasound transducers which are built on a silicon wafer using microfabrication techniques. Custom electronics are used to control the transducers and the system emits sound into the air and receives echoes from objects in front of the transducer array. The proposed ultrasonic 3D rangefinder has the potential to be small and low-power enough to be left on continuously, giving devices such as smartphones, tablets, and wearable electronic devices a way to sense physical objects in the surrounding environment. Based on the smartphone market alone, the potential market size for this device is over one billion units per year. Mobile contextual awareness will enable 3D interaction with smartphones and tablets, facilitating rich user interfaces for applications such as gaming and hands-free control in automobiles. Looking beyond the smartphone and tablet market, the proposed rangefinder will feature size and power advantages that will permit integration into centimeter-sized devices which are too small to support a touchscreen. During Phase II, the major technical goals of this project are to transfer the ultrasound transducer manufacturing from a university laboratory to a commercial production facility, to develop a custom integrated circuit for signal processing, and to develop engineering prototypes. In Phase I, micromachined ultrasound transducers having a novel structure designed to improve manufacturability were developed and a demonstration prototype was built using signal processing algorithms running on a personal computer. In Phase II, the ultrasound transducers will be manufactured in a commercial facility for the first time and signal processing algorithms will be realized on a custom mixed-signal integrated circuit. A prototype package for the transducer and integrated circuit chips will be developed and detailed acoustic testing of the packaged prototypes will be conducted.