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BIOMECHANICAL 3-D ANALYSIS OF A HUMAN SIT-TO-STANDING SEQUENCE 
USING TWO CCD VIDEO CAMERAS 
Masako TSURUOKA, Ryosuke SHIBASAKI, Elgene O. BOX, Shunji MURAI 
Murai Lab., Dept. of 5th, Institute of Industrial Science, University of Tokyo 
7-22-1, Roppongi, Minato-ku, Tokyo 106 JAPAN 
Tel: + 81-3-3402-6231 Ext. 2560. 1. 2. 3, Fax: + 81-3-3479-2762 
E-mail : masako@shuniji.iis.u-tokyo.ac.jp 
Eiji MORI, Dept. of Rehabilitation, National Higashi Saitama Hospital, JAPAN 
Takao WADA, Dept. of Internal Medicine, Inagi Municipal Hospital, JAPAN 
KEY WORDS: Biomechanical Analysis, Center of Gravity, Moment of Inertia, Kinetic Energy, 3-D Videogrammetry 
ABSTRACT 
Recently, biomechanical 3-D analysis of human movement has become more important for medical kinesitherapy in 
rehabilitation. This paper presents a new approach employing a personal computer-aided system for analysis of the sit-to- 
standing movement in hemiplegic patients. This study is based on three components: a system of a synchronization of 
hardware linking the two CCD video cameras, a 3-D videogrammetric system for non-metric cameras with self-calibration 
and 3-D biomechanical analyses of human movement. Dynamic analyses were done focusing especially on the following 
aspects in biomechanical analysis: Center of body gravity, Moment of inertia, Angular velocity, Kinetic energy. It was 
observed that the seriously hemiplegic patients have difficulties in flexion and extension movements of knee joints of the 
plegic-side of the body, instability of the center of body gravity and larger moment of inertia and kinetic energy. This system 
will be used widely in the field of rehabilitation. 
1. INTRODUCTION 
Biomechanical 3-D analysis of human movement has attracted more and more attention in medical rehabilitation. It 
applies principles of physical dynamics to the analysis of human movement. In this study, a new personal computer-aided 
system using two non-metric CCD video cameras was developed. When the personal computer is operated, the video 
recorders which are linked to the two CCD video cameras are configured to start and stop simultaneously. Fig.1 shows the 
synchronization hardware system for hemiplegic subjects who cannot walk alone, the ability to stand up from a chair is an 
important factor for maintaining independence in their daily lives. Fig. 2 shows a hemiplegic patient who are using a wheel 
in the rehabilitation center of the hospital. By observing the standing sequence, through comparative dynamic experiments 
on seriously or moderately hemiplegic patients, one can see that each plegic-side of the body carries stress in daily 
movement and also that each normal-side has burdens. The results of the present study suggest that 3-D video- 
grammetry and biomechanical algorithms and analysis provide important indexes for a quantitative understanding of patient 
movement for medical kinesitherapy in the field of rehabilitation. 3 
Video Controller 
LED 
| Swicth CPU Main Controller 
Amplifier MC6821 
  
  
  
  
  
  
  
  
  
  
  
  
CCD Video Camera 
     
Human Movement 
Fig. 1 The Synchronized System Fig. 2 Hemiplegic Patient using a Wheel Chair 
IAPRS, Vol. 30, Part 5W1, ISPRS Intercommission Workshop "From Pixels to Sequences", Zurich, March 22-24 1995 
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