# Design and Application of the BiVib Audio-Tactile Piano Sample Library
## 1 Introduction  
During instrumental performance musicians are exposed to auditory, visual and also somatosensory cues. This multisensory experience has been studied since long [1; 2; 3; 4; 5], however the specific interaction between sound and vibrations has been object of systematic research since the 1980's [6; 7; 8; 9; 10; 11; 12], when tactile and force feedback cues started to be recognized to have a prominent role in the complex perception-action mechanisms occurring during musical instrument playing [13]. More recently, research on the somatosensory perception of musical instruments has been consolidated, as testified by the emerging \"musical haptics\" topic [14]. This increased interest is partly due to the increased availability of accurate yet affordable sensors and actuators, capable of recording touch gestures and rendering vibrations and force, respectively. Using these devices, complex experimental settings can be realized to measure and deliver multisensory information in a musical instrument, often as a result of a real-time analysis and synthesis process taking place during the performance [15; 16; 17]. Once integrated with traditional audio microphone and loudspeaker systems, touch sensors and actuators can be employed first to investigate the joint role of the auditory and somatosensory modality in the perception of a musical instrument, and then torealize novel musical interfaces and instruments building on the lessons of the previous investigation. Through this process, richer or even unconventional feedback cues can be conveyed to the performer, with the aim of increasing engagement, and hence the initial acceptability and subsequent playability of the new instrument [18; 19; 20; 21]. In this scenario, the availability of multimodal databases combining and synchronizing different streams of information (audio, video, kinematic data of the instrument and performer in action, physiological signals, interactions among musicians etc.) is increasingly recognized as an essential asset for studying music performance. Recent examples include the \"multimodal string quartet performance dataset\" (QUARTET) [22], the \"University of Rochester multimodal music performance dataset\" (URMP) [23], the \"database for emotion analysis using physiological signals\" (DEAP) [24], the \"TU-Note violin sample library\" [25]. Furthermore, initiatives aiming at systematizing the creation of these databases have recently appeared, such as RepoVizz [26], a framework for storing, browsing, and visualizing synchronous multimodal data. Overall, this scenario suggests an increasing attention to the design of musical instrument sound databases, motivated by the concrete possibility for their content to be reproduced in instrumental settings including not only loudspeakers and headphones, but also haptic and robotic devices. The piano represents an especially relevant case study not only for its importance in the history of Western musical tradition, but also for its potential in the musical instruments market due to the universality of the keyboard interface, a feature that has traditionally induced novel musical instrument makers to propose conservative instances of the standard piano keyboard whenever this interface made possible to control even revolutionary sound synthesis methods [27]. It is no accident that, also in recent years, sales of digital pianos and keyboard synthesizers have shown a growing trend as opposed to other instrument sales ([[https://www.namm.org/membership/global-report](https://www.namm.org/membership/global-report)]([https://www.namm.org/membership/global-report](https://www.namm.org/membership/global-report))). For the same reason, researchers on new musical instruments have steadily elected the piano keyboard as the platform of choice for designing expansions of the traditional paradigm, affording a performer to accurately play two local selections of 88 available tones with the desired amplitude and temporal development [28; 29].