A Relationship Study on the Biomechanically Assessed Height and Weight-Frequency Combinations of Manual Lifting and Lowering Operations

• Main Authors: Chia-Chien Ho, 何佳倩
• Other Authors: Lai-Chin Lu
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/31174317674991411060

碩士 === 國立高雄應用科技大學 === 工業工程與管理系 === 99 === This study uses biomechanics to investigate the relationship between lifting and lowering operations and the lumbar vertebrae, by employing The MotionMonitor™ 3D motion detection system and entering the angle values from the motion capture system into the IOSH handling assessment program. The lower back L5/S1 lumbar vertebral load value data associated with various types of operations from 8 test subjects were collected for this study to understand the impact that the handling operations have on the load level on the lower back L5/S1 lumbar vertebrae region. A total of 12 types of operations were included in this study, namely the BMI groups (BMI<24, BMI>24), handling heights (shoulder height of 135cm, waist height of 95cm, knee height of 55cm), and weight-frequency combinations (7kg at 4 times/minute, 14kg at 2 times/minute). The results revealed that: 1. Based on the assessments from the Motion and IOSH models, we know that the lumbar vertebral load value of those with a higher BMI was greater than those with a lower BMI, and the difference was significant. However, the Motion assessment tool showed that the difference in values between these two groups was not significant when the test was conducted at a height of 95cm. 2. Both the Motion and IOSH results indicated that when the handling height was at knee level (≤55cm), the lumbar vertebral load value clearly went up and the difference was significant. 3. Both tools showed significant effects on the lumbar vertebral load value within the weigh-frequency combination tests. The Motion assessment indicated that when handling 14kg twice a minute at a height of 55cm, the pressure within the L5/S1 joints exceeded 4,000N, and it exceeded 3,400N for the IOSH model. Therefore, the handling weight must be a factor of consideration. 4. The IOSH load values were usually significantly higher than that of the Motion assessment, indicating that the IOSH model tended to overestimate the force imposed on the lumbar vertebral region during the assessments. However, when the handling height was at 55cm, the Motion load value was higher than that of the IOSH assessment, indicating that the IOSH assessment model was not as sensitive within the low handling height range. 5. The load value associated with lowering was greater than the load value associated with lifting during the Motion lifting and lowering operation assessment at a height of 55cm, and the difference was significant. There were no significant differences with the other types of operations. However, there were no significant differences in the IOSH lifting and lowering operations within any of the operation types.