Objective: To investigate relationships among grip forces, normal forces, contact area for cylindrical handles, handle diameter, hand size, and volar hand area. Background: Data describing those relationships are needed to predict thrust forces and torque capability. Method: Additional analyses were performed retrospectively on data collected in two previous studies in which participants performed maximum grip exertions on cylinders (diameter 38—83 mm) while grip force, normal force, and contact area were recorded. The length, width, and volar area of the hand were measured. Results: Average total normal force on cylinders was 2.3 times greater than grip force measured using a split cylinder (R2 = 65%), regardless of the handle diameter examined. The ratio of handle diameter to hand length explained 62%, 57%, and 71% of the variances in grip force, normal force, and contact area, respectively. Estimated hand area (hand length × width) had a linear relationship with measured hand area (using photographs; R2 = 91%), although it was 8% less than the measured area. Conclusion: This work describes the relationship between normal force and grip force independent of handle size (for handle diameters from 38 to 83 mm). Normal force and contact area can be explained by the interaction between handle size and hand size. Hand area can be estimated by hand length times width. Application: The quantitative relationships described in this paper can be used in the design of objects and hand tools to determine optimal handle sizes for maximizing grip force, total normal force, or contact area.
Get full access to this article
View all access options for this article.
References
1.
Aghazadeh, F., Waikar, A.M., Lee, K.S., Backhouse, T., & Davis, P. (1989). Impact of anthropometric variables and sex on grip strength. In A. Mital (Ed.), Advances in industrial ergonomics and safety I (pp. 501-505). London: Taylor & Francis.
2.
Aldien, Y., Welcome, D., Rakheja, S., Dong, R., & Boileau, P.-E. (2005). Contact pressure distribution at hand-handle interface: Role of hand forces and handle size. International Journal of Industrial Ergonomics, 35, 267-286.
3.
Amis, A.A. (1987). Variation of finger forces in maximal isometric grasp tests on a range of cylinder diameters. Journal of Biomedical Engineering, 9, 313-320.
4.
An, K.N., Chao, E.Y., Cooney, W.P., & Linscheid, R.L. (1979). Normative model of human hand for biomechanical analysis. Journal of Biomechanics, 12, 775-788.
5.
An, K.N., Ueba, Y., Chao, E.Y., Cooney, W.P., & Linscheid, R.L. (1983). Tendon excursion and moment arm of index finger muscles. Journal of Biomechanics, 16, 419-425.
6.
Ayoub, M.M., & Lo Presti, P. (1971). The determination of an optimum size cylindrical handle by use of electromyography. Ergonomics, 14, 509-518.
7.
Bao, S., & Silverstein, B. (2005). Estimation of hand force in ergonomic job evaluations. Ergonomics, 48, 288-301.
8.
Blackwell, J.R., Kornatz, K.W., & Heath, E.M. (1999). Effect of grip span on maximal grip force and fatigue of flexor digitorum superficialis. Applied Ergonomics , 30, 401-405.
9.
Bobjer, O., Johansson, S.-E., & Piguet, S. (1993). Friction between hand and handle: Effects of oil and lard on textured and non-textured surfaces; Perception of discomfort. Applied Ergonomics, 24, 190-202.
10.
Buchholz, B., Armstrong, T.J., & Goldstein, S.A. (1992). Anthropometric data for describing the kinematics of the human hand. Ergonomics, 35, 261-273.
11.
Bullinger, H.J., Kern, P., & Solf, J.J. (1979). Reibung zwischen Hand und Griff: Der Einfluss von Material und Oberfläche auf das Reibungsverhalten zwischen Hand und Arbeitsmittelhandseite [The effects of materials and surface on the frictional behavior between hand and handle] (Research Report 213). Bremerhaven, Germany: Wirtschaftsverlag NW.
12.
Comaish, S., & Bottoms, E. (1971). The skin and friction: Deviations fromAmonton's laws, and the effects of hydration and lubrication. British Journal of Dermatology, 84, 37-43.
13.
Coulomb, C.A. (1785). Théorie des machines simples [Theory of simple machines]. Mémoire de Mathématique et de Physique de l'Académie Royale, 10, 161-342.
14.
Crawford, J.O., Wabine, E., & Nayak, L. (2002). The interaction between lid diameter, height and shape on wrist torque exertion in younger and older adults. Ergonomics, 45, 922-933.
15.
Dong, R.G., McDowell, T.W., & Welcome, D.E. (2005). Biodynamic response at the palm of the human hand subjected to a random vibration. Industrial Health, 43, 241-255.
16.
Dong, R.G., Schopper, A.W., McDowell, T.W., Welcome, D.E., Wu, J.Z., Smutz, W.P., et al. (2004). Vibration energy absorption (VEA) in human fingers-hand-arm system. Medical Engineering and Physics, 26, 483-492.
17.
Dong, R.G., Wu, J.Z., Welcome, D.E., & McDowell, T.W. (2008). A new approach to characterize grip force applied to a cylindrical handle. Medical Engineering and Physics, 30, 20-33.
18.
Edgren, C.S., Radwin, R.G., & Irwin, C.B. (2004). Grip force vectors for varying handle diameters and hand sizes. Human Factors, 46, 244-251.
19.
Fellows, G.L., & Freivalds, A. (1991). Ergonomics evaluation of a foam rubber grip for tool handles. Applied Ergonomics, 22, 225-230.
20.
Fowler, N.K., Nicol, A.C., Condon, B., & Hadley, D. (2001). Method of determination of three dimensional index finger moment arms and tendon lines of action using high resolution MRI scans . Journal of Biomechanics, 34, 791-797.
21.
Fransson-Hall, C., & Kilbom, A. (1993). Sensitivity of the hand to surface pressure. Applied Ergonomics, 24, 181-189.
22.
Garrett, J.W. (1971). The adult human hand: Some anthropometric and biomechanical considerations. Human Factors, 13, 117-131.
23.
Gemne, G., & Taylor, W. (1983). Foreword: Hand-arm vibration and the central autonomic nervous system. Journal of Low Frequency Noise and Vibration , 2, 1-12.
24.
Grant, K.A., & Habes, D.J. (1993). Effectiveness of a handle flange for reducing manual effort during hand tool use. International Journal of Industrial Ergonomics, 12, 199-207.
25.
Grant, K.A., Habes, D.J., & Steward, L.L. (1992). An analysis of handle designs for reducing manual effort: The influence of grip diameter. International Journal of Industrial Ergonomics, 10, 199-206.
26.
Greig, M., & Wells, R. (2004). Measurement of prehensile grasp capabilities by a force and moment wrench: Methodological development and assessment of manual workers. Ergonomics, 47, 41-58.
27.
Gurram, R., Gouw, G.J., & Rakheja, S. (1993). Grip pressure distribution under static and dynamic loading. Experimental Mechanics, 33, 169-173.
28.
Gurram, R., Rakheja, S., & Gouw, G.J. (1995). A study of hand grip pressure distribution and EMG of finger flexor muscles under dynamic loads. Ergonomics , 38, 684-699.
29.
Hall, C. (1997). External pressure at the hand during object handling and work with tools. International Journal of Industrial Ergonomics , 20, 191-206.
30.
Hanten, W.P., Chen, W.Y., Austin, A.A., Brooks, R.E., Carter, H.C., Law, C.A., et al. (1999). Maximum grip strength in normal subjects from 20 to 64 years of age. Journal of Hand Therapy, 12, 193-200.
31.
Härkönen, R., Piirtomaa, M., & Alaranta, H. (1993). Grip strength and hand position of the dynamometer in 204 Finnish adults. Journal of Hand Surgery, British, 18B, 129-132.
32.
Irwin, C.B., & Radwin, R.G. (2008). A new method for estimating hand internal loads from external force measurements. Ergonomics, 51, 156-167.
33.
Kamper, D.G., Fischer, H.C., & Cruz, E.G. (2006). Impact of finger posture on mapping from muscle activation to joint torque. Clinical Biomechanics, 21, 361-369.
34.
Kong, Y.-K., Freivalds, A., & Kim, S.E. (2004). Evaluation of handles in a maximum gripping task . Ergonomics, 47, 1350-1364.
35.
Kong, Y.-K., & Lowe, B.D. (2005a). Evaluation of handle diameters and orientations in a maximum torque task. International Journal of Industrial Ergonomics, 35, 1073-1084.
36.
Kong, Y.-K., & Lowe, B.D. (2005b). Optimal cylindrical handle diameter for grip force tasks. International Journal of Industrial Ergonomics , 35, 495-507.
37.
Kong, Y.-K., Lowe, B.D., Lee, S.J., & Krieg, E.F. (2007). Evaluation of handle design characteristics in a maximum screwdriving torque task. Ergonomics, 50, 1404-1418.
38.
Lee, J.W., & Rim, K. (1991). Measurement of finger joint angles and maximum finger forces during cylinder grip activity. Journal of Biomedical Engineering, 13, 152-162.
39.
Marcotte, P., Aldien, Y., Boileau, P.-E., Rakheja, S., & Boutin, J. (2005). Effect of handle size and hand-handle contact force on the biodynamic response of the hand-arm system under zh-axis vibration . Journal of Sound and Vibration, 283, 1071-1091.
40.
Mathiowetz, V., Kashman, N., Volland, G., Weber, K., Dowe, M., & Rogers, S. (1985). Grip and pinch strength: Normative data for adults . Archives of Physical Medicine and Rehabilitation, 66, 69-72.
41.
Nagashima, K., & Konz, S. (1986). Jar lids: Effect of diameter, gripping materials and knurling. In Proceedings of the Human Factors Society 30th Annual Meeting (pp. 672-674). Santa Monica, CA: Human Factors and Ergonomics Society.
42.
Peebles, L., & Norris, B. (2003). Filling "gaps" in strength data for design. Applied Ergonomics, 34, 73-88.
43.
Pheasant, S., & O'Neill, D. (1975). Performance in gripping and turning - A study in hand/handle effectiveness. Applied Ergonomics, 6, 205-208.
44.
Pylatiuk, C., Kargov, A., Schulz, S., & Doderlein, L. (2006). Distribution of grip force in three different functional prehension patterns. Journal of Medical Engineering and Technology, 30, 176-182.
45.
Radhakrishnan, S., & Nagaravindra, M. (1993). Analysis of hand forces in health and disease during maximum isometric grasping of cylinders. Medical and Biological Engineering and Computing, 31, 372-376.
46.
Rohles, F.H., Moldrup, K.L., & Laviana, J.E. (1983). Opening jars: An anthropometric study of the wrist-twisting strength of the elderly. In Proceedings of the Human Factors Society 27th Annual Meeting (pp. 112-116). Santa Monica, CA: Human Factors and Ergonomics Society.
47.
Seo, N.J. (2008). Biomechanical models of hand coupling for axial torque and push exertions. Saarbrücken, Germany: VDM Verlag Dr. Müller.
48.
Seo, N.J., &Armstrong, T.J. (2006). A preferred orientation of a cylindrical hand dynamometer for measuring grip force. In Proceedings of the 28th International Congress of the International Commission on Occupational Health (p. 134) [Abstract]. Rome: International Commission on Occupational Health.
49.
Seo, N.J., Armstrong, T.J., & Ashton-Miller, J.A. (2006). Grip forces measured with different methods. In Proceedings of the 16th World Congress of the International Ergonomics Association (IEA) [CD-ROM]. New York: Elsevier Science. Retrieved October 9, 2008, from http://www.ric.org/pdf/Seo_et_al_IEA2006_proceeding.pdf
50.
Seo, N.J.,Armstrong, T.J.,Ashton-Miller, J.A., & Chaffin, D.B. (2007). The effect of torque direction and cylindrical handle diameter on the coupling between the hand and a cylindrical handle . Journal of Biomechanics, 40, 3236-3243.
51.
Seo, N.J., Armstrong, T.J., Chaffin, D.B., & Ashton-Miller, J.A. (2008a). The effect of handle friction and inward/outward torque on maximum axial push force. Human Factors, 50, 227-236.
52.
Seo, N.J., Armstrong, T.J., Chaffin, D.B., & Ashton-Miller, J.A. (2008b). Inward torque and high friction handle can reduce required muscle efforts for torque generation . Human Factors, 50, 37-48.
53.
Seo, N.J., Armstrong, T.J., & Drinkaus, P. (in press). A comparison of two methods of measuring static coefficient of friction at low normal forces: A pilot study. Ergonomics .
54.
Smaby, N., Johanson, M.E., Baker, B., Kenney, D.E., Murray, W.M., & Hentz, V.R. (2004). Identification of key pinch forces required to complete functional tasks. Journal of Rehabilitation Research and Development, 41, 215-224.
55.
Welcome, D., Rakheja, S., Dong, R., Wu, J.Z., & Schopper, A.W. (2004). An investigation on the relationship between grip, push, and contact forces applied to a tool handle . International Journal of Industrial Ergonomics, 34, 507-518.
56.
Westling, G., & Johansson, R.S. (1984). Factors influencing the force control during precision grip. Experimental Brain Research , 53, 277-284.
57.
Wu, J.Z., & Dong, R.G. (2005). Analysis of the contact interactions between fingertips and objects with different surface curvatures. In Proceedings of the I MECH E Part H Journal of Engineering in Medicine, 219, 89-103.
58.
Yakou, T., Yamamoto, K., Koyama, M., & Hyodo, K. (1997). Sensory evaluation of grip using cylindrical objects . Japan Society of Mechanical Engineers (JSME) International Journal Series C, Mechanical Systems, Machine Elements and Manufacturing, 40, 730-735.
