http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Effect of the relative rotation axis position of the stretching machine and ankle
Yuma SHIRAISHI,Shogo OKAMOTO,Naomi YAMADA,Koki INOUE,Yasuhiro AKIYAMA,Yoji YAMADA 제어로봇시스템학회 2019 제어로봇시스템학회 국제학술대회 논문집 Vol.2019 No.10
At the onset of a stroke, paralysis of the lower leg typically causes a foot deformity called the foot drop. Stretching is an effective technique for physical therapy. An automated stretching machine provides the option to incorporate long-term stretching at home. We have remodeled a commercial foot exerciser to function as a stretching machine for ankle dorsiflexion [1]. It is believed that the rotation axis of such machines should be aligned with the biomechanical axis of the human body, which is the design principle our prototype is based on. However, there have been no studies that have investigated the best position of the axis required to achieve effective stretching. In this study, we evaluated several positions of the machine’s rotation axis in the sagittal plane with respect to the stretching effect and physical burden (safety). The force applied on the foot and ankle dorsiflexion angle were measured during the stretching experiments. We computed the work involved in ankle dorsiflexion and the force not contributing to the dorsiflexion movement, which served as indicators for the stretching effect and potential physical burden, respectively. It was found that the best position of the machine’s rotation axis can be above the ankle.
High Accurate Detection of Inclined Cracksin Concrete Structures Using an Acceleration Pickup
Shozou Miyoshi,Masayuki Okamoto,Shogo Tanaka 제어로봇시스템학회 2009 제어로봇시스템학회 국제학술대회 논문집 Vol.2009 No.8
The present paper proposes a method for the detection of inclined cracks in concrete using an acceleration pickup. The sensor on the concrete surface observes the stationary wave sinside the structure whose frequencies depend on the distance to the crack. The method can recognize the profile of the in clined crack with a high accuracy by the following two procedures. The 1st procedure: we model the sensor output as an output of alinear dynamic system with an unknown parameter and measure the accurate propagation distance from the sensor to the crack by applying a maximum likelihood method at each in spection point. The 2nd procedure: we apply a least squares method considering the reflection efficiency of the elastic waves at the inclined crack and the directivity characteristic of the sensor.
Validation of trip-induction system on a treadmill by comparison with a walking lane
Hazuki Miyata,Akiyama Yasuhiro,Yoji Yamada,Shogo Okamoto 제어로봇시스템학회 2019 제어로봇시스템학회 국제학술대회 논문집 Vol.2019 No.10
Trip-related falls, which account for a significant portion of falls by the elderly, often result in serious injury. A method to evaluate fall risk accurately will be increasingly required in the aging society. For this purpose, it is necessary to analyze the natural reaction motion against tripping. We therefore developed a device and method to induce tripping at an arbitrary time during walking on a treadmill. To evaluate the validity of that method, another experiment that induced tripping on a walking lane was conducted. The reaction motions in the two environments were then compared. In this study, we focused on the difference in the preferred walking speed between the ground and the treadmill. The results suggest that the joint patterns during the reaction motion become similar when the subjective velocities, not the physical velocities, become the same for the subject, whereas physical parameters such as the trajectory of the center of mass become similar when the physical velocities match. These results help to understand the reaction motion against tripping and to reproduce the natural reaction motion on the treadmill.
Investigation into Hand Impact Force During Forward Falls on Uneven Terrain
Saeed Abdolshah,Nader Rajaei,Yasuhiro Akiyama,Yoji Yamada,Shogo Okamoto 한국정밀공학회 2020 International Journal of Precision Engineering and Vol.21 No.3
Outdoor falls predominantly occur because of environmental factors, such as tripping caused by uneven terrain; as a result, the faller may land on an uneven surface. Forward falls are among the most frequent causes of fractures. Previous investigations concentrated on the evaluation of impact forces acting on the hand/wrist on even terrains; however, further studies are necessary to evaluate the impact force during forward falls on uneven surfaces, which may occur frequently in daily activities. This study investigated the distal/proximal hand impact force during forward falls on even/uneven terrain. A series of fall experiments in which the distal and proximal areas of the hand contacted the ground simultaneously (even surface) or at different times (uneven surface) was conducted. The results showed that the magnitude of the peak impact forces acting on the distal and proximal areas are strongly associated with the terrain shape and the contact timing. Although in all experiments, a significant portion of the impact force was exerted on the proximal area of the hand, the earlier distal-ground contact reduced the peak proximal impact force significantly. The results of this study are beneficial for finding strategies to reduce fall-related injuries and the design of protective gloves and wrist guards to satisfy fracture prevention requirements.