Evaluation process based on users need : ergonomic evaluation of multimedia games for visually impaired children AurØlie Buaud (1,2), Dominique Archambault (2), Benot Roussel (1), Patrick Truchot (1) (1) Laboratoire de recherche en GØnie des SystLmes Industriels ENGSI-INPL, 8 rue Bastien Lepage, BP 647, 54010 NANCY, France (2) INSERM U483 / INOVA  UniversitØ Pierre et Marie Curie 9, quai Saint Bernard, 75252 Paris Cedex 05, France Keywords : ergonomic evaluation, usability testing, computer games, visually impaired children Abstract The evolution of the design methods in order to create products answering of users needs, pass by the integration of the human sciences. These disciplines such as the ergonomics, the psychology, the sociology (), allow better understanding of needs and human behaviours in front of product. The TiM project (Tactile Interactive Multimedia computer games for visually impaired children) intends to offer to young visually impaired children the possibility to play computer games in an autonomous way. The computer games must be adapted to users needs. To achieve this goal, this project integrates the human factor in this development process, namely during the evaluation process. Through this project, this paper suggests presenting ergonomic evaluation more specifically usability testing. of the computer games for young visually impaired children (3 to 10 years old). Traditional measures of usability such as productivity arent appropriate to evaluate childrens application. The indicators should be challenge, control and satisfaction. In order to improve and design new games, the results concern essentially the sound an tactile interfaces. The recommendations allow to the blind children to navigate and to localise easily in the game. 1. Introduction According to Rabardel [1] " the knowledge of human, of his behaviors, reasoning and representations, must be at the heart of design: in the process of design, the engineering must be centred on the human ". In the research, the ergonomics allow to better understand users needs and human behaviors in order to improve the usability of a product. In the design process, the ergonomic analysis is realised during the extraction of the users needs (to realise products specifications) and during the products evaluation. Through the TiM project (Tactile Interactive Multimedia computer games for visually impaired children) this paper will present the usability evaluation to design multimedia products: computer games for blind children and serve visually impaired children. This project intends to offer to young visually impaired children the possibility to play computer games in an autonomous way. The computer games must be adapted to users needs. To achieve this goal, the team is multidisciplinary with different specialists working in human sciences (ergonomic specialists, therapists specialised in visually impaired children,). Traditional measures of usability such as productivity indices, speed and efficiency of task completion, are not generally appropriate to evaluate childrens products [2].Through examples of adapted games, we will present the objectives of the tests, some results and a adapted game. 2. Usability and Usability testing of computer games 2.1 Usability and Usability testing