Hands are important tools for manual work. Although researchers have identified factors that influence the grip efforts of an entire hand, there appears to be limited research concerning the use of different pinch techniques and how they affect the performance of pinch effort. Therefore, the aim for this pilot study is to determine the effects of different pinch techniques on pinch effort. A total of 110 manual workers from a wooden pallet manufacturing firm participated in this study, which involved an experiment and survey to investigate the most preferred pinch technique applied on screw knobs. The techniques used were the 3-jaw chuck, pulp-2 and lateral pinch. A total of 6 screw knobs of different shapes and sizes were used. After the data were collected, descriptive and Cronbach's alpha reliability analyses were carried out. The results show that the preferred pinch technique for the small cylindrical knob, small sphere knob and all large knobs is the lateral pinch. However, the 3-jaw chuck pinch is preferred for the small 5-lobes knob. This study provides preliminary information for further research on pinch techniques and their influences on the pinching outcomes of individuals.

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Failure in proper design of ergonomic hand tools can lead to the prevalence of hand-related injuries. In order to improve the ergonomics of hand tools, numerous studies have been done on causal factors related to these injuries such as grip postures, grip forces and torque directions. Nevertheless, there appears to be limited studies concerning how pinch effort can change with different types of tactile sensations. Therefore this study aims to determine the effects of different tactile sensations on pinch effort. A total of 110 manual workers from the wooden pallets and furniture manufacturing firm participated in the study. The descriptive analyses were conducted in Microsoft Excel 2010 and the reliability of data was verified using Cronbach's alpha reliability analyses. The results show that individuals can produce a greater pinch effort while gripping objects that have a high friction coefficient between the fingers and the grip surface. This study improves our understanding on the implications of different tactile sensations and potentially decreases workplace hazards for eventual improvements on safety, health and medical costs.

Hand and finger-related injuries are increasingly common in the manufacturing industry. In relation to this, researchers have conducted various studies and found that a clockwise torque can produce a greater grip force than a counterclockwise torque direction, hence improving the grip control and exertion of an individual. However, there appears to be limited studies that explore this theory in the circumstances of pinch grips. Thus, the aim of this study is to explore the effects of different torque directions on the pinch grips. 6 prototype industrial screw knobs were designed, produced and evaluated by surveying 160 workers from a manufacturing firm. The results show that although the sizes are different, the effort to turn the knobs with a counterclockwise torque direction is still greater than the effort with a clockwise torque direction, which can technically mean that the pinch exertion in a clockwise torque direction is relatively greater. Based on these findings, guidelines can be developed to further improve hand tool designs and the capacity of torque exertions to potentially increase human performance and the effectiveness in tasks at the workplace.

The most common body parts that sustain injuries at the workplace are the hands and fingers. In association to this, researchers have conducted various studies on grip span, forces, postures, contact area and strength. However, it appears that limited studies have been done on the design of screw knobs of ergonomic shapes and sizes for pinch grip activities. Thus, the aim of this study is to design, develop and assess screw knobs of ergonomic shapes and sizes for pinching activities. Several designs of screw knobs were designed and fabricated. The assessment of the knobs involved workers from a manufacturing firm. The ratings on the efforts to pinch and turn the knobs were collected using surveys and analyzed with reliability and descriptive and analyses. The results show that the workers mostly preferred using the small 5-lobes knob. However, the large ball knob was the least preferred knob to be used. The findings of this study can be used to create design guidelines on knob shapes and sizes to develop safer, more ergonomic and efficient knobs.