• 한국지능시스템학회논문지
• /
• 제20권6호
• /
• pp.793-798
• /
• 2010

본 논문에서는 소비 에너지 분석을 통한 이족보행로봇의 저전력 보행 보정 기법을 제안하였다. 먼저 이족 로봇의 보행 기본자세의 각 축별 소비 에너지를 분석하여 소비 에너지를 절감하는 기본 보행 자세를 구현하였다. 이족 로봇의 보행 기본자세를 무릎 구부리는 자세로 정하여 소비에너지를 줄이고, 무게중심을 낮추어 자세 안정성을 향상하였다. 이족로봇의 보행시 모터 전류를 측정하여 좌우 다리의 소비 전력을 분석하고, 이를 바탕으로 좌우 에너지 불균형을 제거하도록 보행 자세를 보정하였다. 보행 기본자세의 좌우 소비 전력을 고르게 분포시키게 자세를 보정함으로서 전체 소비 에너지를 감소시키고, 로봇의 좌우 자세 균형을 맞추어 보행시 안정성을 향상하였다. 제안한 소비 에너지 분석을 통한 저전력 보행 구현 방법은 임베디드시스템 기반의 소형 이족 로봇을 실제 제작하여 보행 실험을 통해 성능을 검증하였다.

• 한국지능시스템학회논문지
• /
• 제22권4호
• /
• pp.448-453
• /
• 2012

최근 다양한 환경에서 지능형 로봇의 안정된 이동방법에 대한 연구가 활발히 이루어지고 있다. 본 논문에서는 복합 바퀴-다리형 이동 로봇의 설계 방법을 제안하고, LRF(Laser Range Finder)센서를 이용한 복합 이동형 로봇의 저전력 보행 기반 장애물 회피 알고리즘을 제안하였다. 로봇의 자세 안정화와 소비에너지를 줄이기 위해 모터 전류값을 바탕으로 자세를 보정하여 저전력 보행 알고리즘을 구현하였고, 이를 기반으로 LRF센서를 이용한 장애물 회피 알고리즘을 제안하였다. 로봇의 각 다리에서 소비되는 전력을 고르게 분포시키게 자세를 보정하여 보행을 안정화시키고, 최단 경로로 장애물을 회피하여 이동함으로써 전체 소비 에너지를 감소시키며 보행 안정성을 향상하였다. 본 연구에서 제안한 방법들은 실제 복합 이동 로봇의 보행 및 장애물 회피 실험을 통해 성능을 검증하였다.

• 대한물리치료과학회지
• /
• 제28권3호
• /
• pp.76-87
• /
• 2021

Background: The purpose of this study was to evaluate the effects of power walking and square dancing on middle-aged women with hypertension. Design: Randomized controlled Trial. Methods: 30 middle-aged women with hypertension were selected and divided into two groups. 15 cases in the control group received routine treatment, and 15 cases in the intervention group received community vigorous walking and square dancing intervention on the basis of routine treatment. The intervention time was 40-60minutes/day, 5days/week, total 16 weeks. total cholesterol (TC), triglycerides (TG), high density lipoprotein cholesterol (HDL), low density lipoprotein cholesterol (LDL), angiotensin II (Ang II), Leptin, blood pressure, and heart rate were measured. Results: Body weight, body mass index (BMI), TC, TG, LOW-density lipoprotein, angiotensin II, leptin, systolic blood pressure and heart rate were significantly reduced after power walking and square dancing (p<0.05). After the experiment, TC and TG in the experimental group were lower than those in the control group (p<0.05), while HDL was higher (p<0.05). Conclusion: The results of this study suggest that power walking exercises and square dances are significant effects on lipid mechanism and heart rate.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 2001년도 ICCAS
• /
• pp.171.2-171
• /
• 2001

This paper presents a force control of a arm of walking training robot. The current gait training apparatus in hospital are ineffective for the difficulty in keeping constant unloading level and constraining patients to walk freely. The proposed walking training robot is designed to unload body weight effectively during walking. The walking training robot consists of unloading manipulator and mobile platform. The manipulator driven with a electro-mechanical linear mechanism unloads body weight in various level. The mobile platform is wheel type, which allows to patients unconstrained walking. Unloading system with electro-mechanical linear mechanism has been developed, which has advantages such as low noise level, light weight, low manufacturing cost and low power consumption. A system model for the manipulator ...

• 한국정밀공학회지
• /
• 제19권12호
• /
• pp.38-44
• /
• 2002

A walking training robot is proposed to provide stable and comfortable walking supports by reducing body weight load partially and a force control of an arm of walking training robot using sliding mode controller is also proposed. The current gait training apparatus in hospital are ineffective for the difficulty in keeping constant unloading level and for the constraint of patients' free walking. The proposed walking training robot effectively unloads body weight during walking. The walking training robot consists of an unloading manipulator and a mobile platform. The manipulator driven by an electro-mechanical linear mechanism unloads body weight in various levels. The mobile platform is wheel type, which allows patients to walt freely. The developed unloading system has advantages such as low noise level, lightweight, low manufacturing cost and low power consumption. A system model fur the manipulator is established using Lagrange's equation. To unload the weight of the patients, sliding mode control with p-control is adopted. Both control responses with a weight and human walking control responses are analyzed through experimental implementation to demonstrate performance characteristics of the proposed force controller.

• The Journal of Korean Physical Therapy
• /
• 제27권4호
• /
• pp.228-233
• /
• 2015

Purpose: Gait is the most basic element when evaluating the quality of life with activities of daily living under ordinary life circumstances. Symmetrical use of the lower extremities requires complicated coordination of all limbs. Thus, this study examined asymmetry of muscle activity quadriceps femoris and tibialis anterior as a baseline for training during over-ground walking and stair walking of stroke patients. Methods: Subjects were 14 stroke patients included as one experimental group. Gait speed used in this study was determined by the subject. Low extremity paretic and non-paretic EMG was compared using the surface EMG system. Results: The low extremity EMG difference was statistically significant during over-ground walking and stair walking (p<0.05). The result of low extremity EMG substituted symmetry ratio formula was compared to EMG symmetry ratio in both legs during over-ground walking and stair walking. The average symmetry ratio of quadriceps femoris during over-ground walking was 0.65, and average symmetry ratio of quadriceps femoris during stair walking was 0.47, with significant difference (p<0.05). Conclusion: EMG data was higher in stair walking than over-ground walking. However, in the comparison of symmetry ratio, asymmetric EMG of quadriceps femoris was significantly increased during stair walking. These findings suggested that application of stair walking for strengthening of both legs can be positive, but the key factor is maintaining asymmetrical posture of both legs. Therefore, physical therapists should make an effort to reduce asymmetry of quadriceps femoris power during stair walking by stroke patients.

• 한국지능시스템학회논문지
• /
• 제16권4호
• /
• pp.443-448
• /
• 2006

본 논문에서는 이족 로봇 보행 중 전력 소비가 적고 안정한 저전력 보행 궤적 생성 방법을 재안하고, 생성된 보행 궤적의 구현을 위해 25 자유도를 갖는 이족 로봇을 설계 제작하였다. 본 논문에서 제안된 방법에서는 발목 사용 보행의 장점을 이용하고 보행 중 무릎을 크게 굽히는 동작을 줄이기 위해 기존 보행 방법과는 달리 우선 가장 안정한 VPCG 궤적을 생성 하고 생성된 궤적에 따른 발목과 골반의 보행 궤적을 생성한다. 이와 같이 함으로써 이족 로봇이 보행 중 항상 무릎을 굽히지 않으므로 전체 보행 중 전력 소비를 최소화 한다. 한편 제작된 이족 로봇은 발목 사용 시 지면과 잘 접지되는 발 구조와 골반을 유연하게 동작 할 수 있는 특징을 가진다. 마지막으로 이족 로봇의 실제 보행 실험 및 소비 전력 측정 결과, 본 논문에서 제안된 방법이 발목을 사용하지 않는 기존 방법에 비해 더 안정하고 전력 소비가 더 적음을 확인할 수 있었다.

• Nuclear Engineering and Technology
• /
• 제49권3호
• /
• pp.632-637
• /
• 2017

Even though the potential for an accident in nuclear power plants is very low, multiple emergency plans are necessary because the impact of such an accident to the public is enormous. One of these emergency plans involves a robotic system for investigating accidents under conditions of high radiation and contaminated air. To develop a robot suitable for operation in a nuclear power plant, we focused on eliminating the three major obstacles that challenge robots in such conditions: the disconnection of radio communication, falling on uneven floors, and loss of localization. To solve the radio problem, a Wi-Fi extender was used in radio shadow areas. To reinforce the walking, we developed two- and four-leg convertible walking, a floor adaptive foot, a roly-poly defensive falling design, and automatic standing recovery after falling methods were developed. To allow the robot to determine its location in the containment building, a bar code landmark reading method was chosen. When a severe accident occurs, this robot will be useful for accident condition monitoring. We also anticipate the robot can serve as a workman aid in a high radiation area during normal operations.

• 한국운동역학회지
• /
• 제24권2호
• /
• pp.167-172
• /
• 2014

The purpose of this study was to investigate walking standard time and joint powers of the lower extremities on the changes of illuminations in the elderly women. Ten older women ($70.90{\pm}3.28$ years, $154.70{\pm}3.47$ cm, $53.80{\pm}5.39$ kg) with normal vision and no gait disabilities participated in this study. All the experiments were performed on a level walkway from low to high lighting (six conditions). A 3-dimensional motion capturing system, force-plate, and EMG were used to acquire and analyze walking motion, force, and muscle activity data; the sampling frequency was 100 Hz, 1000 Hz and 1000 Hz respectively. To test the differences on walking standard time and joint powers of the lower extremities between the six lighting conditions, one-way repeated ANOVAs were evaluated. The following results were drawn: First, mean standard time was about 1.3 sec/stride, and velocities were smaller with lighting increasing except 100 Lx. Second, the joint power patterns of ankle and knee were not consistent, but only hip joint power was a greatest in 6 Lx and a smallest in 400 Lx. Third, standard times(100 Lx<300 Lx, 400 Lx) were statistically significant, and hip joint max powers (100 Lx>others) were also statistically significant. But ankle and knee joint max power were not statistically significant. These results showed that standard times from low to high lighting were not consistent, and hip joint of 100 Lx has a greatest rotational torque. We suggested that gait strategies of them as to changing illuminations were not consistent and findings may represent a lack of adaptability in the elderly women.

• 한국기계기술학회지
• /
• 제13권4호
• /
• pp.137-141
• /
• 2011

Driving mechanism, the central part of a robot, was designed in this study. Power for the motive drive was acquired by directly connecting the motor shaft in worm shape of the low-end DC motor, car window motor, to a decelerator. The decelerator consists of a worm gear to receive power from the motor shaft, a pinion gear to be connected in line with the worm gear, and an output shaft to be engaged to the pinion gear. Motion driving is achieved by the power from the motor shaft with the designed gears, transferred to the deceleration mechanism and to the output gear.