An investigative sensitivity study of Ovako working posture analyzing system (OWAS)

Abstract The purpose of this study is to investigate the sensitivity of the Ovako working posture analyzing system. This paper also focuses on the identification of insensitive and highly sensitive posture zones. The OWAS sensitivity analysis, together with the ordinal regression analysis, offers deeper insights into the methodology for assessing posture. A full factorial design was used to account for all possible combinations of body members. To assess the sensitivity, one parameter of the body part was changed while other parameters were left unchanged to understand its effect on the output score. Combinations of postures in which no change was observed and corresponding ranges were noted. Posture ratings with sudden jumps were also noted. Ordinal regression analysis was performed to identify the body variable with the greatest impact and its weight in estimating the OWAS action category. Ergonomic practitioners can be made aware of insensitive and sensitive zones when assessing posture.