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Dear colleagues on Biomch-L:
I had some problems in reading the article:
Davis, RB III, Ounpuu, S, Tyburski, D, and Gage, JR (1991). A gait data
collection and reduction technique. Human Movement Sciences 10, 575-587.
On page 583, they provided equations for the hip joint. In my observation
based on figure 3 on the same page, equations 5 and 7should read as
follows:
Xh = - ( Xdis + Rmarker ) * cos(BETA) - C * cos(THETA) * sin(BETA) (5)
Zh = + ( Xdis + Rmarker ) * sin(BETA) - C * cos(THETA) * cos(BETA) (7)
where, THETA = 28.4 deg (SD = 6.6 deg), and BETA = 18 deg (SD = 4 deg). The
meaning of Xdis, Rmarker are provided in the article.
Am I misunderstading something here or is it just a matter of typo? Or BETA
could be negative. I wish to get some input from the readership of Biomch-L
and especially from the authors of the paper.
Thanks!
Young-Hoo
---------------------------------------------------------
Young-Hoo Kwon, Ph.D.
Senior Researcher, Biomechanics Department
Korea Sport Science Institute
223-19 Gongneung-2-Dong
Seoul, 139-242
KOREA
Phone: +82-2-9709-555
Fax: +82-2-9709-502
Internet: y-hkwon@sports.re.kr
---------------------------------------------------------
Effective on August 1, 1997
---------------------------------------------------------
Assistant Professor
Biomechanics Laboratory, PL202
School of Physical Education
Ball State University
Muncie, IN 47306
U.S.A.
---------------------------------------------------------
I had some problems in reading the article:
Davis, RB III, Ounpuu, S, Tyburski, D, and Gage, JR (1991). A gait data
collection and reduction technique. Human Movement Sciences 10, 575-587.
On page 583, they provided equations for the hip joint. In my observation
based on figure 3 on the same page, equations 5 and 7should read as
follows:
Xh = - ( Xdis + Rmarker ) * cos(BETA) - C * cos(THETA) * sin(BETA) (5)
Zh = + ( Xdis + Rmarker ) * sin(BETA) - C * cos(THETA) * cos(BETA) (7)
where, THETA = 28.4 deg (SD = 6.6 deg), and BETA = 18 deg (SD = 4 deg). The
meaning of Xdis, Rmarker are provided in the article.
Am I misunderstading something here or is it just a matter of typo? Or BETA
could be negative. I wish to get some input from the readership of Biomch-L
and especially from the authors of the paper.
Thanks!
Young-Hoo
---------------------------------------------------------
Young-Hoo Kwon, Ph.D.
Senior Researcher, Biomechanics Department
Korea Sport Science Institute
223-19 Gongneung-2-Dong
Seoul, 139-242
KOREA
Phone: +82-2-9709-555
Fax: +82-2-9709-502
Internet: y-hkwon@sports.re.kr
---------------------------------------------------------
Effective on August 1, 1997
---------------------------------------------------------
Assistant Professor
Biomechanics Laboratory, PL202
School of Physical Education
Ball State University
Muncie, IN 47306
U.S.A.
---------------------------------------------------------