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KINE 3301 Biomechanics of Human Movement. Center of Mass. Chapter 12. Segmental Method for Computing Center of Mass. Segment Segment Weight (N ) CM Location (%) Proximal End Head 0.032 x BW + 18.70 66.3 Top of Head Trunk 0.532 x BW – 6.93 52.2 1 ST Cervical
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KINE 3301 Biomechanics of Human Movement Center of Mass Chapter 12
Segmental Method for Computing Center of Mass Segment Segment Weight (N) CM Location (%) Proximal End Head 0.032 x BW + 18.70 66.3 Top of Head Trunk 0.532 x BW – 6.93 52.2 1STCervical Upper Arm 0.022 x BW + 4.76 50.7 Shoulder Forearm 0.013 x BW + 2.41 41.7 Elbow Hand 0.005 x BW + 0.75 51.1 Wrist Thigh 0.127 x BW – 14.82 39.8 Hip Lower Leg 0.044 x BW – 1.75 41.3 Knee Foot 0.009 x BW + 2.48 40.0 Ankle From: Chandler, R. F., C. E. Clauser, et al. (1975).
How to Use Segmental Method • Determine the X, Y location of the endpoints of all body segments. • Determine the weight of each segment. • Determine the location of each segments center of mass. • Multiply the segment weights by the x or y coordinates and then divide by the total weight to determine the location of the body center of mass.
Sagittal View Example Segment Segment Weight (N) CM Location (%) Proximal End Head 0.032 x BW + 18.70 66.3 Top of Head Trunk 0.532 x BW – 6.93 52.2 1ST Cervical Thigh0.127 x BW – 14.82 39.8 Hip In the back handspring assignment we are assuming that the right and left limbs move symmetrically, so the weights must be doubled, in cell F5 enter the following: =2*((0.127*$L$2)-14.82)