Keigo Matsushima Tomonori Kubota Haruka Murakami Satoshi Sato Kohei Ogawa Voice Volume Gauge: A Minimal Interface Solution for Operator's Vocal Adaptation in Teleoperated Social Robots. 2026 June 77 18 Int. J. Soc. Robotics 5 https://doi.org/10.1007/s12369-026-01416-9 db/journals/ijsr/ijsr18.html#MatsushimaKMSO26 streams/journals/ijsr