Influences of Tactile Sensation on Pinch Force under Loaded and Unloaded Conditions

Although researchers have studied various parameters that affect grip force, few studies investigate the effects of tactile sensation on pinch force. This study aims to determine the influences of tactile sensation on pinch force with a special emphasis on screw knobs under loaded and unloaded conditions. The participants included 32 manual workers who were required to pinch and turn the knobs to generate pinch force under reduced and increased sensations simulated using cotton and nitrile gloves. The data were analysed using the analysis of variance via Minitab 16. Results show that the pinch force exerted for reduced sensations is higher than that of increased sensations because the reduced friction increased skin-object slippages, which caused participants to spontaneously increase their force to prevent slippages. This study serves as a guideline to potentially improve the design of objects operated with pinch grips to be safe and suitable for manual, sedentary or general tasks.