A Study on Ergonomic Hazard and Compatibility of Controls in Operator Cab of Overhead Cranes

• Main Authors: Chih-Hsian Hsu, 許智翔
• Other Authors: Cheng-Lung Lee
• Format: Others
• Language: zh-TW
• Published: 2003
• Online Access: http://ndltd.ncl.edu.tw/handle/bkzd72

碩士 === 朝陽科技大學 === 工業工程與管理系碩士班 === 91 === Abstract The overhead cranes are the most widely used electric-mechanical aids for raising, lowering as well as moving large and heavy loads through a limited distance on the shop-floors in factories. Some injuries occurred from manual handlings can then be reduced. The purpose of this study was to explore the operators’ cognition of safety and health, symptom of musculoskeletal disorders and issue of movement compatibility of controls in crane cab through the 152 effective questionnaires. Furthermore, the working postures of cab operators were video-taped in workplaces and then saved into computer in laboratory with a freeze frame every 30 seconds. A total of 63 working postures was coded and analyzed with the techniques of OWAS and RULA. In the study, the result showed that 50% of workers required high skills and 73.6% paid high attention during crane operations. There were 90.1% of 152 interviewees experienced musculoskeletal pains in the past. More than 50% of workers suffered in neck, shoulder, upper and lower back. As to the part of movement compatibility of the controls, the motion setting in up/down direction for joystick and poke shaft is different between experienced and inexperienced cab operators. The relevant departments and organizations need to have attention. With the techniques of OWAS and RULA, the risk of working postures of cab operators exists. It was showed that 61.9% for AC2 (OWAS) and 12.6% for AL2, 69.8% for AL3, 17.5% for AL4 (RULA). The result revealed that the outcomes are apparently different in these two evaluation systems and RULA is more accurate due to the characteristics of sitting posture, repetitive motion of upper limbs, and vibration factor in the working environment for cab-operating task.