This study aimed to analyze the muscular activity associated with the proper function, stability, and mobility of the shoulder joint. In the field of orthopedics, the shoulder joint is recognized as having extensive mobility. Using an electromyograph (sEMG), the muscular activity in 10 elderly male subjects was analyzed during joint movements while performing isokinetic exercises. The muscular activity of an agonist was analyzed using both the percent maximum voluntary contraction (%MVC) and the EMG (µV) value before normalization. The %MVC quantified four motions (flexion, extension, abduction, and adduction) for the 10 upper limb muscles whereas the latter did not. The results showed that the pectoralis major (clavicular insertion) activated as an agonist during abduction and adduction. A comparison of when the muscles activated based on each motion revealed that the middle deltoid muscle activated the fastest during abduction. This research is expected to facilitate measurement of the shoulder function for both rehabilitation equipment and their associated programs.

Objective: The aim of this study is developing an elderly automatic showering system by optimizing nozzle position and angle of water injection on ergonomics approach. Background: The elderly living in nursing home or hospital were increased by an aging population. Helping the elderly on showering is so hard. In addition, the existing showering/bathing systems are not effective because shower pattern of the elderly and washed range of nozzle were not considered. Method: Firstly, basic specification were determined by anthropometric approach. Secondly, position of nozzle and angle of water injection were determined through observation of elderly behavior on showering. And, finally, they were optimized by washing test and showering simulation. Results: On showering importance of body parts were able to analysis through observation of elderly behavior. The position of nozzle and angle of water injection was able to optimize by showering simulation. The automatic showering system was developed by considering their results. Conclusion: The most important technology of developing a showering system is the determining position of nozzle and angle of water injection, number of nozzle. It was developed by applying its results through user centered-research. Application: The user centered-research of developing products was able to apply directly to develop automatic bath, showering products etc. Further more it was available to apply senior friendly products.

Objective: The aim of this study is to set the design direction of the lift chair's tilting seat for development. Background: Great attention has been shown to the development of senior friendly product, because of increasing elderly population rapidly in Korea. Therefore, we need to study on sit-to-stand(STS) motion of elderly systematically for developing lift chair that is one of senior friendly products. Method: In this study, we analyzed joint moment(knee, hip) and muscle activity (Erector spinae, Rectus femoris, Vastus lateralis) on STS motion of elderly(female, 60~70: 7) and young people(female, 20~30: 7) using 3 dimension motion capture camera, force plate, wireless EMG. Results: The results of muscle activity showed a similar trend but the results of joint moment were a lot of differences between the young and the elderly. Conclusion:The results of knee joint moment suggest the angle(10~30deg)-adjustable seat that can be better than to find the optimal seat's angle. Application: The method and results of this study are expected to develop senior friendly product and verification as well as be available to various application.

Objective:The aim of this study is to design an auto showering system regarding bed type for old people or bedridden patients. Background: The rapid growth concerning the aging population leads to an increase in elderly bedridden patients living in senior care centers and hospitals where care givers have difficulty bathing older people with limited mobility. Method: In this study, a showering equipment for experiment was based on anthropometric and researching existing products. The nozzle position was optimized by showering tests and simulations using showering equipment. Results: The problems regarding the existing products were analyzed and the nozzle position was optimized through showering tests. The number, position, and spraying angle of the nozzle were optimized through showering simulations. The automatic showering system concerning bed type was designed by considering their results. Conclusion: When designing an automatic showering system, the most important design element involves determining the position of nozzle and angle of water injection and the number of nozzles. The system was developed by applying the results through user centered-research. Application: The user centered-research for developing products was applied directly in order to develop automatic baths, showering products etc. Furthermore, it was also available to be applied towards senior friendly products.