Indoor Navigation System by Combining Ultrasonic Wave TOA and Inertial Measurement. - Romprakhun Tientadakul; Hiroaki Nakanishi; Tomoo Shiigi; Zichen Huang; Lok Wai Jacky Tsay; Naoshi Kondo (SICE, 2020)

A Noise Tolerant Spread Spectrum Sound-Based Local Positioning System for Operating a Quadcopter in a Greenhouse. - Zichen Huang; Lok Wai Jacky Tsay; Tomoo Shiigi; Xunyue Zhao; Hiroaki Nakanishi; Tetsuhito Suzuki; Yuichi Ogawa; Naoshi Kondo (Sensors, 2020)

A sound-based positioning system with centimeter accuracy for mobile robots in a greenhouse using frequency shift compensation. - Zichen Huang; Tomoo Shiigi; Lok Wai Jacky Tsay; Hiroaki Nakanishi; Tetsuhito Suzuki; Yuichi Ogawa; Naoshi Kondo (Comput. Electron. Agric., 2021)

Spread Spectrum Sound with TDMA and INS Hybrid Navigation System for Indoor Environment. - Romprakhun Tientadakul; Hiroaki Nakanishi; Tomoo Shiigi; Zichen Huang; Lok Wai Jacky Tsay; Naoshi Kondo (J. Robotics Mechatronics, 2021)