Validation of a computer-simulation model for human ambulation on stilts.
Pan-C; Miller-K; Chiou-S; Kau-T; Current-R
American Industrial Hygiene Conference and Exposition, May 8-13, 2004, Atlanta, Georgia. Fairfax, VA: American Industrial Hygiene Association, 2004 May; :3
The objective of this study is to validate a model to evaluate overexertion and potential fall-related injuries associated with the use of stilts. Under normal gait conditions, this computerized model could be used to evaluate stresses in various anatomical joints and simulate whole-body postural instability. Three construction workers between the ages of 34 and 40 with at least 12 months of experience in the use of stilts were recruited for walking tasks on 24-inch stilts. Twenty-eight reflective markers were placed on the subjectís body and stilts. The model was validated using whole body center of mass and ground reaction forces. A PEAK motion system and two Kistler force platforms were used to collect data, producing an output file with time-synchronized records of both kinetic and kinematic measures. Inverse- and direct-dynamics simulations were performed using the model to generate center of mass and ground reaction force. For three coordinates (X, Y, Z) of the center of mass, the results of univariate analyses indicated very small variability (0.14 cm +/- 0.11 cm, 5.4 cm +/- 0.07 cm, 3.71 cm +/- 0.03 cm) for the mean difference between the model and the actual measurement. The results of correlation analyses indicated similar trends for three coordinates (rx = 0.82, ry = 0.88, rz = 0.99). Plotting the magnitude and vertical ground reaction force for both right and left feet showed small discrepancies, but the overall shape was identical between the model and the actual measurement. The percent difference between the model and the actual measurement for three coordinates of the center of mass, as well as magnitude and vertical ground reaction force, never exceeded 20%. Using this validated model, researchers will be able to examine whether stilt use increases the joint loadings and postural instability parameters while walking on stilts.
Simulation-methods; Models; Injuries; Posture; Demographic-characteristics; Age-factors; Analytical-models; Analytical-methods; Humans; Construction-workers
Disease and Injury: Traumatic Injuries
American Industrial Hygiene Conference and Exposition, May 8-13, 2004, Atlanta, Georgia