ArmKeyBoard: a mobile keyboard instrument based on chord-scale system and tonal hierarchy

Abstract

Traditional keyboard instruments, with their sheer size and key anisotropy, although are versatile in musical expression, are difficult to learn and inconvenient to carry around; and its linear layout somewhat rules out the musical possibility of non-linearity. Trying to address this, we design a keyboard with both linear and non-linear layouts based on chord-scale system and tonal hierarchy. Several flipping mechanisms and mapping algorithms are devised to try to equip this small portable keyboard with as much musical expression capability as possible as compared with a traditional keyboard. Evaluation results show that both the musical outcome and user experience of ArmKeyBoard are satisfactory, although people may still prefer a linear keyboard to a non-linear one.