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Digital Definition of the Deflected Shape of the Human Body in Seated Postures for Ergonomic Design in CAD Models
ISSN: 0148-7191, e-ISSN: 2688-3627
Published June 26, 2001 by SAE International in United States
Annotation ability available
An advanced biofidelic shape of the human body is needed in computer-aided design (CAD) models for ergonomic design. To be used in seat and automotive design, this advance in biofidelity must be a 3D CAD tool that includes the deflected shape of the human body and must include skeletal landmarks, especially those related to load paths. The CAD tools must represent the range of the population and must also represent the full range of seated postures.
To develop our CAD models, a 3D anthropometric study was undertaken that used skeletal landmarks to define relative positions of transverse cross-sections that describe both the “visible” and “invisible” shape of the seated body. Data were collected on large males, average males and small females. Subjects were measured in several postures while sitting on flat foam pads. Transverse sections were measured at the center of gravity of each thigh, under the ischial tuberosities and at the S2, L4, T8 and T4 spinal levels. A coordinate measurement machine (CMM) was used in conjunction with a strain strip to measure the shape of each section. The resulting transverse sections define the deflected shape (patent pending) of the seated body for three body sizes.
The transverse section data were combined with 2D center line sections (patent pending) developed previously. Skeletal landmarks were used to define frames of reference to combine the transverse sections with the center line sections of the human body. The shape between regions was interpolated with C2 continuity using the transverse sections and center line curves as controls. The resulting models of the body define the 3D biofidelic seated shape that is required to estimate the design of the optimal seat and seating package for the human occupant-driver.
CitationBrodeur, R. and Reynolds, H., "Digital Definition of the Deflected Shape of the Human Body in Seated Postures for Ergonomic Design in CAD Models," SAE Technical Paper 2001-01-2106, 2001, https://doi.org/10.4271/2001-01-2106.
SAE 2001 Transactions Journal of Passenger Cars - Mechanical Systems
Number: V110-6; Published: 2002-09-15
Number: V110-6; Published: 2002-09-15
- Manary MA Schneider LW Flannagan CC Eby BH Evaluation of the SAE J826 3D manikin. Measures of driver positioning and posture SAE 941048 Warrendale, PA 1994
- Schneider LW Robbins DH Pflug MA Snyder RG Development of anthropometrically based design specifications for an advanced adult anthropometric dummy family 1 1983
- Frost BL Hubbard RP Boughner RL Development of human back contours for automobile seat design SAE 970590 Warrendale, PA 1997
- Robinette, K.M. CAESAR Measures Up. Ergonomics in Design 8 3 17 23 Human Factors and Ergonomics Society Santa Monica, CA 2000
- Yamazaki N 1992 Analysis of sitting comfortability of driver's seat by contact shape Ergonomics 35 5 6 677 692
- Reynolds HM Brodeur RR Aljundi S. ERL, A CAD-based model of human occupants in SAE Human Factors in Seating Comfort 2001. SAE 2001-01-0393 World Congress Detroit, MI March 5-8 2001
- Reynolds HM Hubbard RP Anatomical frames of reference and biomechanics Human Factors 22 2 171 176 1980
- Ugural AC 1991 Mechanics of Materials McGraw-Hill, Inc. NY
- Brodeur, RR Cui, Y. Reynolds, HM Locating the Pelvis in the Seated Automobile Driver SAE 960481 Automotive Design Advancements in Human Factors: Improving Drivers' Comfort and Performance (SP-1155) 41 48 SAE Warrendale, PA 1996
- Dempster, WF Space Requirements of the Seated Operator Geometrical, Kinematic, and Mechanical Aspects of the Body with Special Reference to the Limbs Wright Air Development Center July 1955
- Gordon, CC et al. 1988 Anthropometric Survey of U.S. Army Personnel: Methods and Summary Statistics US Army Natick Research, Development and Engineering Center Natick, MA 01760-5000 September 1989
- SAE Standard J826 Devices for the use in defining and measuring vehicle seating accommodation Body Eng Comm, Soc. Auto. Eng, Approv. Nov. 1962
- Setyabudhy RH Ali A Hubbard RP Beckett C Averill RC Measuring and modeling of human soft tissue and seat interaction SAE 970593 Warrendale, PA 1997