| Summary: | 碩士 === 國立成功大學 === 機械工程學系 === 103 === The objectives of this study are to use mechanism analysis and inertial sensor-based motion capture system as an inexpensive alternative solution to optical motion capture system, and provide informations of upper limb joint loads during wheelchair propulsion which would be practical to wheelchair design with lower man power and joint loads.
A measurement system and upper limb/wheelchair spatial mechanism model for analyzing upper limb joint loading during the push phase of manual wheelchair propulsion was developed. The measurement system was based on MEMS inertial sensor. It consisted of one triaxial accelerometer and one triaxial rate gyroscope, and a micro control unit (MCU) for receiving informations from inertial sensing units. The upper limb/wheelchair system is a closed-loop kinematic chain, sensors can be placed on upper arm to obtain kinematic data for calculating attitude angles of upper arm. The measurements from sensor were transmitted to computer through MCU for upper limb joint forces analysis. The upper limb/wheelchair spatial mechanism model in the study is SRSR spatial mechanism, it consisted of four linkages and two ball-and-socket joints and two revolute joints. The mechanism model can analyze joints angular displacement and trajectory using homogeneous coordinate transformation matrices, joint loads, driving moments and resisting moments by kinetostatics analysis.
Experiments were done with a healthy volunteer. The result of angular displacement shows high accurate of measurement system, and the results of kinetostatics analysis indicate that the slope of ground surface has significant effect to the increase in joint loads and moments.
|
|---|
