Proceedings of ISon 2019, 6 th Interactive Sonification Workshop, KTH Royal Institute of Technology, Sweden, November 18, 2019 INTERACTIVE SONIFICATION FOR CORRECTION OF POOR SITTING POSTURE WHILE WORKING Kotaro Okada Graduate School of Kyoto Sangyo University Department of Frontier Information Science Kyoto, Japan i1888024@gmail.com Shigeyuki Hirai Kyoto Sangyo University Faculty of Information Science and Engineering Kyoto, Japan hirai@cse.kyoto-su.ac.jp ABSTRACT People who sit while working may unconsciously take a bad pos- ture, such as a stoop. It causes a high physical load or may result in poor work efficiency. Since a bad posture occurs when people are in a state of concentration, they may not notice it by themselves. In order to solve this problem, we propose a system to make the posture state noticeable without disturbing the work significantly. This system indicates a bad posture via sounds in real-time, includ- ing the ambient music, by applying interactive sonification. This paper describes our prototype system for interactive sonification of postures while sitting, along with the sound designs. We also discuss results from a preliminary evaluation of our sound designs, with regard to their usefulness in helping users notice and correct bad postures. 1. INTRODUCTION Changes in the social workforce over the past few decades have forced office workers to spend a long time sitting in the work- place. This, coupled with a lifestyle that tends to make people sit at home, results in health problems such as back and neck injuries[1]. Keeping a bad posture for a long time has been shown to exacer- bate health problems[2]. There is evidence that links the use of computers to the risk of developing musculoskeletal pain and dis- orders. A survey of 512 office workers found that the prevalence of neck pain for 12 months was 45.5%[3]. Reports of lifetime prevalence of neck pain in the general population range from 67- 80%[4]. Without proper measures, an increase in the prevalence of neck pain is expected. Over time, poor posture can cause pain, muscle pain, tension, headaches, and long-term complications such as osteoarthritis[5]. Most upper limb disorders and symptoms (neck, shoulder, elbow, and wrist pain) are associated with the use of computers on poorly- positioned workstations[6]. As one of the factors necessary to maintain a stable sitting po- sition, Shibata cites ”attention to sustain in work activities”[7]. A person can detect a poor posture based on physical factors such as stable sitting balance ability and sensory feedback and can main- tain a sitting posture in an appropriate posture. However, main- taining an ideal sitting posture during work activities requires the ability to handle dual tasks, that is, the ability to concentrate on the work activity while simultaneously detecting and correcting bad postures. It is very difficult for most people to check their pos- ture while working on a task[8]. Many techniques for solving this problem use visual feedback, but on-screen warnings may not be appropriate as warnings because they can interfere with the tasks being performed on the computer[9]. During this decade, there has been an increase in the recogni- tion of interactive sonification[10] using non-verbal sounds. This is a field of information audibility and auditory display research[11]. Interactive sonification is defined as the use of sound within a tightly closed human computer interface where the auditory sig- nal provides information about the data being analyzed or the in- teraction itself. By applying this method, it is considered possible to notify posture deterioration without interfering with the user’s work. The sound requires design aspects that considers the balance between work concentration and notification of posture deteriora- tion. This research aims to examine the sound design of the posture correction system that converts posture into sounds interactively and does not disturb the user s work. This paper describes the outline of the prototype system, its sound design, and the result of a preliminary evaluation. However, the current research is at an early stage, and the design policy and content of each sound set have aspects of trial and challenge. 2. RELATED WORK 2.1. Interactive Sonification Research on the application of interactive sonification includes studies by Matsubara et al.[12], Hirai et al. Bathonify[13], and Cesarini et al.[14]. In a study by Matsubara et al., which was con- ducted in the field of rehabilitation, they developed and evaluated a system that makes slight angular changes in the ankle accord- ing to the frequency pitch of a continuous sine wave source. It was shown that auditory feedback is not inferior to visual feed- back. Hirai et al.’s Bathonify converts bathers’ movements and biological information into sound effects and music to improve the experience of bathers and manage their health and safety from outside the bathroom. In a study by Cesarini et al., An interactive acoustic representation of hydrodynamic pressure changes caused by a swimmer’s hand-water-interaction induced more symmetri- cally the hand motion in sports swimming. As a result, it was evaluated that the functional sound helps to change the interaction between hands and water. 2.2. Posture Correction by Interactive Sonification Studies on the audibility of posture include the posture improve- ment assist systems developed by Enokibori et al. [15] and Itami et ISon2019-1 101