Postural analysis in HMI design: an extension of OCRA standard to evaluate discomfort level

Purpose: The aim of this work consists in developing a design methodology for preventive ergonomics and comfort analyses of Human-Machine-Interface (HMI). Design/methodology/approach: Our method is based on the simulation of the main posture that a digital human model (a manikin representing, for example, a car’s driver) takes while using a machine (in this work, driving a car), in order to judge human safety and comfort during interaction with dashboard, instruments’ panel, levers and other commands. The ergonomic analyses are made using an appropriately modified OCRA (Occupational Repetitive Actions Index) protocol, in order to evaluate different involvement degrees of upper limb segments in comfort action range. Findings: The three-F principle -Human fit, form and functionis becoming the most addressed guideline for improvement and appeal-increasing of product in the current demanding global marketplace. Our work uses modern technologies and new design methods, developed by our research team, and allows to manage and optimize Human Machine Interface under “comfort” point of view. Research limitations/implications: Today, designers attempt to elaborate product development methodologies that conform itself towards best comfort performance; our work helps them to override several problems that a product development plan shows. Future developments can be made using biomechanical parameters and studies in order to better quantify and evaluate the comfort parameters. Practical implications: Using our approach and methods, comfort analysis can be made in the earliest part of the design development of a product so that designers can appreciably reduce time to market and improve and innovate comfort performances. Originality/value: First paper on this matter has been presented by one of the authors in 2008 in a World Automotive Congress; it has been the first paper on this specific matter. All over the world, new research frontier, on these topics, is going towards HMI evaluation under physical comfort and cognitive ergonomics point of view. Our paper represents, today, the newest and more specific development method, especially in automotive field of research.