Study of workability and safety of welding using virtual human model

Abstract

Recently, Japan has become a nation of aged people, and the shipbuilding industry is not excluded. To increase productivity and to maintain the safety and health of the workers in such circumstances, the current production system must be reviewed so that it will be suitable to human-oriented production. Development of biomechanics and ergonomics, together with a computer simulation technique, helps to establish a virtual ergofactory, which effectively combines both productivity and humanity. This paper focuses on welding, which is a typical job in shipbuilding, as an example of human task simulation by a virtual human model on a computer: The static strength prediction on the human body and lower back compression analysis to prevent lower back pain, the industrial disease of welders. As a result, the torque and/or forces on each segment and joint in the human body were calculated in accordance with the various working postures of welding. These showed that the welder would suffer from severe torque on the knee and also heavy compression force on the lower back in the usual squat posture (flat position). The standing position of the welder would be better for his/her health compared with the squat posture.