A Multi-String Traversing Violin-Playing Robot for Carnatic Music

Abstract

Over the past several decades, robotic musicianship researchers have mainly focused on Western music with only limited efforts addressing musical styles from other regions, such as South Indian Classical music (a.k.a. Carnatic music) - a music form popular in the southern part of India. In this work, we present Hathaani v2, a robotic system capable of performing Carnatic music on the violin. The robot is designed to translate pitch information into left-hand finger placement and amplitude information into bowing changes and dynamics, based on any monophonic audio recording. The left-hand mechanism is capable of reaching arbitrary finger positions along the strings, allowing the robot to play gamakas - continuous pitch ornamentations that are fundamental to Carnatic music. The differential bowing mechanism provides both pressure and angle modulation, while maintaining mechanical rigidity and allowing visual engagement for the audience. We assessed the system’s ability to perform gamakas through expert listening studies involving ten professional musicians on intonation, timbre, quality of bowing, hand coordination, gamaka authenticity, and clarity. The proposed robot outperforms the baseline on all of the evaluated parameters, achieving average scores exceeding 4 on a 5-point Likert scale (0.5 increments). This work has the potential to transform education and production of Carnatic music by offering programmatic solutions that support complex gamakas. Compared to software-based emulations, this physical violin-playing robot offers an accurate and expressive medium for conveying the nuances of Carnatic music performance.