시각적 피드백을 이용한 수동휠체어 주행훈련 시스템의 생리적 및 기계적 효율성 분석

강정선,홍응표,김규석,장윤희 한국재활복지공학회 2022 재활복지공학회논문지 Vol.16 No.2

Wheelchair propulsion exercise is a beneficial aerobic exercise for wheelchair users who are easily exposed to metabolic or cardiovascular diseases due to lack of exercise. However, simple and repetitive indoor wheelchair propulsion exercise on a wheelchair treadmill gives users boredom and making it difficult to continue exercising for a long time. Recently, the development of an exercise system that adds interest and fun by using virtual reality technology is in progress. Therefore, our research institute developed a virtual reality-based non-immersive wheelchair driving training system that provides visual feedback during wheelchair propulsion. In this study, the difference in physiological and mechanical efficiency according to the provision of visual feedback during wheelchair propulsion was compared and analyzed for 10 people with spinal cord injury and lower extremity amputation. As a results of the study, under condition of visual feedback, the heart rate, maximum oxygen consumption, and respiration rate per minute significantly increased(p<.05) as the wheelchair driving speed and propulsion frequency increased by 36.5% and 12.4%, respectively, and it was confirmed that the force transmission efficiency in the traveling direction during wheel propulsion significantly increased. In the state where visual feedback was provided, the subject proceeded with more active wheel propulsion, which is consequently interpreted as improving the mechanical efficiency and physiological factors for wheel propulsion. Providing visual feedback during wheelchair treadmill exercise is expected to help improve exercise efficiency of wheelchair users. 운동부족으로 인해 대사성 또는 심혈관 질환에 노출되기 쉬운 휠체어 사용 장애인들에게 휠체어 추진 운동은 유익한 유산소 운동이다. 그러나 실내 휠체어 트레드밀 위에서 수행되는 단순·반복적인 휠체어 추진 운동은 사용자에게 지루함을 유발하여 장시간 지속적인 운동을 어렵게 만든다. 최근에는 가상현실 기술을 활용하여 흥미와 재미를 추가한 운동 시스템의 개발이 이루어지고 있다. 이에 본 연구소에서는 휠체어 추진 운동 중 시각적 피드백이 제공되는 가상현실 기반의 비몰입형 휠체어 주행훈련시스템을 개발하였다. 본 연구에서는 척수손상과 하지절단으로 인한 휠체어 사용자 10명을 대상으로, 휠체어 추진 시 시각적 피드백의 제공 유무에 따른 생리적 및 기계적 효율성의 차이를 비교 분석하였다. 연구결과, 시각적 피드백이 제공된 상태에서 휠체어 주행 속도와 추진 빈도가 각각 36.5%, 12.4% 증가하면서 휠체어 주행 중 심박수, 최대 산소 소비량 및 분당 호흡률이 유의하게 증가하였으며(p<.05), 휠 추진 시 직진 방향의 힘 전달 효율이 유의하게 증가함을 확인하였다. 시각적 피드백이 제공된 상태에서 피험자는 보다 활동적인 휠 추진을 진행하였고, 이는 결과적으로 휠 추진에 대한 기계적 효율성과 생리적 요인을 향상시킨 것으로 해석된다. 휠체어 트레드밀 운동 시 시각적 피드백의 제공은 휠체어 사용자의 운동 효율성을 향상시키는데 도움이 될 것으로 기대된다.

Torque and Power Outputs on Different Subjects during Manual Wheelchair Propulsion under Different Conditions

황선홍,김승현,손종상,김영호 한국물리학회 2012 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.60 No.3

Manual wheelchair users are at a high risk of pain and injuries to the upper extremities due to mechanical inefficiency of wheelchair propulsion motion. The kinetic analysis of the upper extremities during manual wheelchair propulsion in various conditions needed to be investigated. We developed and calibrated a wheelchair dynamometer for measuring kinetic parameters during propulsion. We utilized the dynamometer to investigate and compare the propulsion torque and power values of experienced and novice users under four different conditions. Experienced wheelchair users generated lower torques with more power than novice users and reacted alertly and sensitively to changing conditions. We expect that these basic methods and results may help to quantitatively evaluate the mechanical efficiency of manual wheelchair propulsion.

Upper Limb Joint Motion of Two Different User Groups During Manual Wheelchair Propulsion

황선홍,김승현,손종상,김영호,이진복 한국물리학회 2013 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.62 No.4

Manual wheelchair users have a high risk of injury to the upper extremities. Recent studies have focused on kinematic and kinetic analyses of manual wheelchair propulsion in order to understand the physical demands on wheelchair users. The purpose of this study was to investigate upper limb joint motion by using a motion capture system and a dynamometer with two different groups of wheelchair users propelling their wheelchairs at different speeds under different load conditions. The variations in the contact time, release time, and linear velocity of the experienced group were all larger than they were in the novice group. The propulsion angles of the experienced users were larger than those of the novices under all conditions. The variances in the propulsion force (both radial and tangential) of the experienced users were larger than those of the novices. The shoulder joint moment had the largest variance with the conditions, followed by the wrist joint moment and the elbow joint moment. The variance of the maximum shoulder joint moment was over four times the variance of the maximum wrist joint moment and eight times the maximum elbow joint moment. The maximum joint moments increased significantly as the speed and load increased in both groups. Quick and significant manipulation ability based on environmental changes is considered an important factor in efficient propulsion. This efficiency was confirmed from the propulsion power results. Sophisticated strategies for efficient manual wheelchair propulsion could be understood by observation of the physical responses of each upper limb joint to changes in load and speed. We expect that the findings of this study will be utilized for designing a rehabilitation program to reduce injuries.

수동 휠체어 추진 속도에 따른 상지 관절 생체역학적 영향 분석

황선홍 대한의용생체공학회 2022 의공학회지 Vol.43 No.4

It is known that chronic pain and injury of upper limb joint tissue in manual wheelchair users is usually caused by muscle imbalance, and the propulsion speed is reported to increase this muscle imbalance. In this study, kinematic variables, electromyography, and ultrasonographic images of the upper limb were measured and analyzed at two different propulsion speeds to provide a quantitative basis for the risk of upper extremity joint injury. Eleven patients with spinal cord injury for the experimental group (GE) and 27 healthy adults for the control group (GC) par- ticipated in this study. Joint angles and electromyography were measured while subjects performed self-selected com- fortable and fast-speed wheelchair propulsion. Ultrasound images were recorded before and after each propulsion task to measure the acromiohumeral distance (AHD). The range of motion of the shoulder (14.35 deg in GE; 20.24 deg in GC) and elbow (5.25 deg in GE; 2.57 deg in GC) joints were significantly decreased (p<0.001). Muscle activation levels of the anterior deltoid, posterior deltoid, biceps brachii, and triceps brachii increased at fast propulsion. Spe- cifically, triceps brachii showed a significant increase in muscle activation at fast propulsion. AHD decreased at fast propulsion. Moreover, the AHD of GE was already narrowed by about 60% compared to the GC from the pre-tests. Increased load on wheelchair propulsion, such as fast propulsion, is considered to cause upper limb joint impingement and soft tissue injury due to overuse of the extensor muscles in a narrow joint space. It is expected that the results of this study can be a quantitative and objective basis for training and rehabilitation for manual wheelchair users to prevent joint pain and damage.

표준형 휠체어 추진시 휠손잡이 촉수위치 특성에 관한 연구

권혁철(Kwon Hyuk-Cheol),공진용(Kong Jin-Yong) 한국전문물리치료학회 2002 한국전문물리치료학회지 Vol.9 No.2

The purpose of this paper is to provide the reader with a pertinent information and research trends of biomechanics in wheelchair propulsion. Biomechanical studies for wheelchair propulsion mainly focus on the most suitable propulsion performance and methods for preventing upper extremity injuries. Recent issue have concentrated on wheelchair propulsion style and cycle mainly because of the high prevalence of repetitive strain injuries in the upper extremely such as shoulder impingement and carpal tunnel syndrome. Optimizing wheelchair propulsion performances as well as medical reflections are presented throughout the review. Information on the underlying musculoskeletal mechanisms of wheelchair propulsion has been introduced through a combination of data collection under experimental conditions and a more fundamental mathematical modelling approach. Through a synchronized analysis of the movement pattern and muscular activity pattern, insight has been gained in the wheelchair propulsion dynamics of people with a different level of disability (various level of physical activity and functional potential). Through mathematical modelling, simulation, and optimization (minimizing injury and maximizing performance), underlying musculoskeletal mechanisms during wheelchair propulsion is investigated.

Effects of Tire Pressure on Biceps Brachii and Triceps Brachii Activity When Operating a Manual Wheelchair

( Sang-yeol Lee ),( Su-kyoung Lee ) 대한물리의학회 2016 대한물리의학회지 Vol.11 No.3

PURPOSE: This study was measured the differences in the flexor and extensor muscle activities of the elbow joints based on the tire pressure of wheelchairs during propulsion, investigating the optimal tire pressure for improving occupants’ propulsion and avoiding related injury. METHODS: Ten healthy volunteers (10 men aged 23.1 ± 1.9 years, weight: 67.9 ± 3.4 kg, height: 175.1 ± 2.7 cm) took part in the study. The mean values used in the statistical process were obtained from values measured while a subject sitting on a wheelchair propelled himself forward for 10 meters on a flat floor at maximum speed. The tire pressure of the wheelchairs was set at 100 psi, 50 psi, and 25 psi. All of the subjects performed wheelchair propulsion for each pressure. This study was measured the activation of the biceps brachii and triceps brachii muscles on the dominant side during wheelchair propulsion. The measured data was analyzed using one-way analysis of variance (ANOVA) via the statistical package for the social sciences (SPSS) version 12.0 for Windows to compare the muscle activity. RESULTS: The muscle activities of the biceps brachii and triceps brachii were significant differences between each pressure group. The post hoc test found statistically significant differences between 100 psi and 50 psi and 100 psi and 25 psi for the biceps brachii and triceps brachii muscles, respectively. CONCLUSION: The maintaining proper tire pressure in a wheelchair may help to prevent overuse syndrome in the occupant’s elbow joints.

운동역학 : 트레드밀 상에서 휠체어 추진시 속도 변화에 따른 추진 기술의 차이 규명

임비오(ImBiO) 한국체육학회 2004 한국체육학회지 Vol.43 No.2

The purpose of this study was to investigate propulsive strategies of the wheelchair with changes of treadmill speed (1.11, 1.39, 1.67, and 2.22 m/s). Nine basketball-wheelchair college athletes were participated in this study. The model of basketball wheelchair (Model: BW-02) was 16 degrees of camber, 61cm of the size of rearwheel, 32cm of the height of seatback, 41cm of seat length, 38cm of the width of frame, and 56cm of the height of the frame. Two dimensional analysis was performed with using recorded data from VHS camera. ANOVA was used for statistical analysis. The results of this study was followed. First, according to the increases of speed, the recovery time remained constant whereas cycle time was decreased with decreases of propulsive time. The decreases of cycle time caused the increases of propulsive frequency. Second, the beginning of angle was decreased with increases of speed. While the end of angle was increased, there was no changes in propulsive angle. Third, with increases of speed, hand was closely approached to the TDC. This explained that the direction of force was apply to the vertical axis. It decreased the negative horizontal force of upper body and wheelchair. Fourth, there were characteristics of performance between push and pull range of handrim at the low speed. However, there was found for the push range at the high speed. This study analyzed the differences of propulsive strategies on treadmill. It would guide to plan for wheelchair training program and to teach strategies

Optimal Seat and Footrest Positions of Manual Standing Wheelchair

유제성,손종상,조민,최은경,안순재,김신기,김영호 한국정밀공학회 2017 International Journal of Precision Engineering and Vol.18 No.6

A standing wheelchair is highly recommended to an individual suffering from secondary complications due to long-term sitting in a standard wheelchair. However, the newly-designed standing wheelchair has hand rims separate from the wheels, likely affecting the biomechanical characteristics and the efficiency of propulsion. The objectives of this dissertation were aimed to propose a method to determine the optimal riding position by evaluating energy expenditure during manual standing wheelchair propulsion. Ten elderly male subjects were asked to propel the hand rims with nine different seat (while sitting) and footrest (while standing) positions. During the experiments, kinematic and kinetic data were simultaneously obtained using a 3D motion capture system and a brake-type wheelchair dynamometer, respectively. Upper-limb joint torques and total propulsion energy were determined using a planar link-segment model with the optimization technique based on minimal joint torque criteria. Shorter subjects had the lowest total propulsion energy expenditure in the downward-forward and middle-forward positions, while closest to the hand rims. However, taller subjects had the lowest total propulsion energy expenditure in the downward-center and middle-center positions, while a little further from the hand rims. We believe that these methods and results will be helpful in assessing the adequacy of the riding position of various types of wheelchair.

수동 휠체어 추진 중 상지 역동역학 모델

송성재(S. J. Song) 한국재활복지공학회 2013 재활복지공학회논문지 Vol.7 No.1

수동 휠체어의 추진은 추진 동작의 낮은 효율로 인하여 사용자의 상지 관절에 고통과 부상까지 유발할 수 있다. 이에 따라 수동 휠체어 추진 중에 발생하는 상지 관절의 운동역학적 해석이 필요하다. 본 연구에서는 수동 휠체어 추진 중 상지 관절에 작용하는 토크를 구할 수 있는 2차원 역동역학 모델을 개발하였다. 개발한 모델은 시상면에서 상완, 하완, 손에 해당하는 3개의 체절로 상지를 구성하였고 몸통으로부터 3개의 체절을 회전조인트로 연결한 개방연쇄구조를 갖는다. 역동역학 해는 뉴턴-오일러 방법으로 구하였고 요구되는 입력자료는 실험을 통하여 획득하였다. 수동 휠체어 추진에 필요한 상지 거동의 운동학적 자료는 3차원 동작분석 시스템에서 추출하였고 역동역학 모델의 외력에 해당하는 운동역학적 자료는 브레이크식 다이나모미터에서 추출하였다. 역동역학 모델을 이용한 해석을 통하여 수동 휠체어 추진에 따른 상지 관절의 회전각과 관절 토크를 구하였다. 개발된 모델은 상지 관절에 관한 생체역학적 해석 도구이며 적은 노력으로 3차원 역동역학 모델로 확장하는 토대가 된다. Manual wheelchair propulsion can lead to pain and injuries of users due to mechanical inefficiency of wheelchair propulsion motion. The kinetic analysis of the upper limbs during manual wheelchair propulsion needs to be studied. A two dimensional inverse dynamic model of upper limbs was developed to compute the joint torque during manual wheelchair propulsion. The model was composed of three segments corresponding to upper arm, lower arm and hand. These segments connected in series by revolute joints constitute open chain mechanism in sagittal plane. The inverse dynamic method is based on Newton-Euler formalism. The model was applied to data collected in experiments. Kinematic data of upper limbs during wheelchair propulsion were obtained from three dimensional trajectories of markers collected by a motion capture system. Kinetic data as external forces applied on the hand were obtained from a dynamometer. The joint rotation angles and joint torques were computed using the inverse dynamic model. The developed model is for upper limbs biomechanics and can easily be extended to three dimensional dynamic model.

의자차 뒷바퀴 축의 위치에 따른 의자차 추진력과 지구력

이미영,김수일 한국전문물리치료학회 2003 한국전문물리치료학회지 Vol.10 No.2

This study was carried out to help the comprehensive rehabilitation of spinal cord injuries by measuring propulsion force and endurance exerted on wheelchair handrims, and predicting the differences among three different rear axle positions. The BTE (Baltimore Therapeutic Exerciser) work simulator was used on 9 paraplegia to test the force and endurance during wheelchair propulsion. The 141 large wheel of the BTE work simulator and a standard wheelchair with removed handrims were used for simulating wheelchair propulsion. The neurological and demographical characteristics of the patients were collected by personal interviews and direct examinations. The Kruskal-Wallis test was used to compare force and endurance among the groups. The strongest maximum isometric strength was produced when the rear axle of the wheelchair and the acromion process were on the same coronal plane. Although there were no significant differences statistically, moving the rear axle forward did result in greater isotonic strength. The research suggests that better functional activity of persons with paraplegia is possible when the rear axle of the wheelchair is appropriately adjusted.