Development of a Washer-Dryer with Kansei Ergonomics

Washer-dryer machines with slanted drums have recently become popular in Japan. Using three-dimensional motion capture devices, we measured and analyzed user posture while using such machines. Subjective Kansei and usability questionnaires were also used. After the measurements, the usersʹ postures were analyzed with a human kinematic model. Three types of machines were used for the experiment: a European-type horizontal-drum washer, a conventional Japanese washer with a vertical drum and a new washer-dryer design with a higher-profile slanted drum. The sum of the estimated percentage of maximum voluntary contraction (elbow, hip, knee, ankle) for the new washer-dryer was 116; it was 133 (knee tension was high) for the European washer and 284 (ankle tension was 110, which exceeds the limit) for the conventional Japanese washer. Subjective fatigue and overall evaluations rated the new washer-dryer significantly better than the European and conventional Japanese washers.The operation of an automatic washing machine is complex and difficult because of its many functions. The usability of the control panel on the new SANYO AQ3000 washing machine was also improved. We conducted usability experiments in both the planning and preproduction phases using software and hardware prototypes. The first part of the evaluation using a software prototype highlighted the requirement to clarify the distinction between operating phases. The second evaluation experiment compared between the previous model and a new hardware prototype which buttons were relocated. We confirmed that the result was more usable than the previous model. The new model AQ3000 was released in February 2008 and was well received in the marketplace.