Peak volitional torques for wrenches and screwdrivers

Abstract Effects of grip shape (regular, circular, square, and triangular), wrist orientation (3 for screwdrivers and 7 for wrenches) and duration of repeated exertions on the maximum torque males and females could exert in different postures with 4 wrenches and 4 screwdrivers were investigated experimentally. Quantitative data were collected by conducting two independent sequential experiments. Circular grips for wrenches and triangular grips for screwdrivers maximized torque exertion capability. The peak torque declined with the duration of repeated exertions but stabilized after 180 s. Wrist orientation also had a significant influence on how much torque individuals could exert. A third experiment generated torque data for two additional body postures that were not included in previous works. From this investigation, correction factors were developed to generate peak torque exertion capability data of individuals with wrenches and screwdrivers for a variety of conditions dictated by body posture, wrist orientation, duration of repeated exertions, and grip shape. The paper includes the basic torque exertion capability design data tables and the correction factors.

[1]  A Mital,et al.  Maximum Acceptable Weight of Lift as a Function of Material Density, Center of Gravity Location, Hand Preference, and Frequency , 1983, Human factors.

[2]  Vernard Foley,et al.  Dynamics of the Axe Swing , 1978 .

[3]  H. Hertzberg.  SOME CONTRIBUTIONS OF APPLIED PHYSICAL ANTHROPOLOGY TO HUMAN ENGINEERING , 1955 .

[4]  W Karwowski,et al.  Isometric and isokinetic testing of lifting strength of males in teamwork. , 1986, Ergonomics.

[5]  A. Mital.  Maximum weights of lift acceptable to male and female industrial workers for extended work shifts. , 1984, Ergonomics.

[6]  K H Kroemer,et al.  Coupling the Hand with the Handle: An Improved Notation of Touch, Grip, and Grasp , 1986, Human factors.

[7]  A. D. Swain,et al.  Maximum Torque for Small Knobs Operated with and without Gloves , 1970 .

[8]  Anil Mital,et al.  Relationship between Lifting Capacity and Injury in Occupations Requiring Lifting , 1978 .

[9]  A Mital,et al.  Effect of body posture and common hand tools on peak torque exertion capabilities. , 1986, Applied ergonomics.

[10]  C G Drury.  Handles for manual materials handling. , 1980, Applied ergonomics.

[11]  Stephan Konz.  Design of Handtools , 1974 .

[12]  R M White.  The Anthropometry of United States Army Men and Women: 1946–1977 , 1979, Human factors.

[13]  Stephan Konz.  Bent Hammer Handles , 1986 .

[14]  D O'Neill,et al.  Performance in gripping and turning -a study in hand/handle effectiveness. , 1975, Applied ergonomics.

[15]  John A. Roebuck,et al.  Engineering Anthropometry Methods , 1975 .

[16]  A. Mital,et al.  Maximum Frequencies Acceptable to Males for One-Handed Horizontal Lifting in the Sagittal Plane , 1983, Human factors.

[17]  M. M. Ayoub,et al.  Male-Female Differences in Variables Affecting Performance , 1978 .

[18]  R DRILLIS,et al.  The Theory of Striking Tools , 1963, Human factors.

[19]  M. M. Ayoub,et al.  The determination of an optimum size cylindrical handle by use of electromyography. , 1971, Ergonomics.

[20]  Michael W. Riley,et al.  An Evaluation of Knife Handle Guarding , 1986, Human factors.

[21]  M. M. Ayoub,et al.  Modeling of Isometric Strength and Lifting Capacity , 1980 .

[22]  Anil Mital,et al.  A study of factors defining the ‘operator-hand tool system’ at the work place , 1985 .

[23]  W. M. Keyserling,et al.  Preemployment strength testing: an updated position. , 1978, Journal of occupational medicine. : official publication of the Industrial Medical Association.

[24]  William S. Marras,et al.  An Evaluation of Tool Design and Method of Use of Railroad Leverage Tools on Back Stress and Tool Performance , 1986, Human factors.

[25]  P Andlauer,et al.  Oral temperature, circadian rhythm amplitude, ageing and tolerance to shift-work. , 1980, Ergonomics.

[26]  Anil Mital,et al.  Development of non-linear polynomials in identifying human isometric strength behaviour , 1984 .

[27]  M W Riley,et al.  The Effects of Handle Shape and Size on Exerted Forces , 1986, Human factors.

[28]  D. L Corrigan,et al.  Axe use efficiency A work theory explanation of an historical trend , 1981 .

[29]  Anil Mital,et al.  Comparison of Maximum Volitional Torque Exertion Capabilities of Males and Females Using Common Hand Tools , 1986 .

[30]  Colin G. Drury,et al.  Hand Placement in Manual Materials Handling , 1983 .

[31]  E R Tichauer,et al.  Ergonomic principles basic to hand tool design. , 1977, American Industrial Hygiene Association journal.

[32]  James V. Bradley.  Effect of Gloves on Control Operation Time , 1969 .

[33]  D B Chaffin,et al.  Ergonomics guide for the assessment of human static strength. , 1975, American Industrial Hygiene Association journal.

[34]  John G. Kreifeldt,et al.  Toward a Theory of Man-Tool System Design Applications to the Consumer Product Area , 1974 .

[35]  Thomas H. Rockwell,et al.  An Experimental Evaluation of Method and Tool Effects in Spike Maul Use , 1986 .

[36]  James V. Bradley.  Glove Characteristics Influencing Control Manipulability , 1969 .