• Journal of the Korean Society for Precision Engineering
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• v.23 no.2 s.179
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• pp.172-180
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• 2006

Although there existed many types of manual/power hybrid wheelchairs, their use was not widespread because of their inconvenience in converting drive system and in folding frames. To carry a wheelchair in the car or to convert driving methods, some hard work of disassembling or exchanging wheels was required for most of currently available hybrid wheelchairs. In this study, the standard foldable manual wheelchair was reformed to a power wheelchair by installing the newly developed Axial Flux Permanent Magnet(AFPM) type of brush less direct current(BLDC) motor on each rear hub of wheelchair. This wheelchair could be driven by manual or electric power without exchanging. wheels, thus no additional work was needed for carriage or for power conversion. The developed wheelchair was evaluated for durability, stability, maneuverability, cost, and reliability in accordance with the Korean standards. The results indicated that the developed hybrid wheelchair was good enough for commercialization comparing to other imported wheelchairs.

• Journal of the Ergonomics Society of Korea
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• v.33 no.2
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• pp.109-124
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• 2014

Objective: This study was conducted for one-hand users including hemiplegic clients currently using general folding manual wheelchairs, so as to analyze their specific problems and recommend solutions regarding usage. Background: Traditional manual wheelchairs require considerable use and control of both hands for operation, thus adaptations become necessary for individuals with asymmetrical use of hands. Method: Thirty hemiplegic clients who were admitted to rehabilitation and convalescent hospitals participated as subjects. The research tools were general folding manual wheelchairs commonly used by people with impaired gait, and the Wheelchair Skills Tests (WST) WST-M/WCU 4.1 version was adopted as the assessment tool. All participants were asked to fill out questionnaires on demographics and wheelchair usage characteristics. Assessment procedures were performed with currently used manual wheelchairs and with/without the use of foot to control the wheelchair. Results: When the participants drove folding manual wheelchairs without the use of foot, even the lowest failure rate among the WST items tested recorded 96.7%. On the contrary, with the use of foot in maneuvering the wheelchairs, failure rates dropped noticeably and success rate among the WST items tested was as high as 86.7%. Conclusion: These findings imply that the use of one-arm (hand) propellable (drivable) wheelchair can be an active and effective solution in resolving problems for hemiplegic clients using existing manual wheelchairs. As such, the government should provide institutional support to further develop and distribute this device or technology, and promote relative research in tandem. For now, the supply of commercially available device to hemiplegic clients is deemed urgent and also a mechanism to provide the devices and relevant services. Application: This study offers viable solutions for hemiplegic clients who rely on existing manual wheelchairs to increase their mobility and occupational performance.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.05a
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• pp.1421-1422
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• 2010

• Proceedings of the KSME Conference
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• 2001.06c
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• pp.464-469
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• 2001

This work provides the biomechanical evaluations of a manual wheelchair with a bi-directional driving system. The new propulsion strategy can be accomplished by employing a special gear system that converts the oscillatory motion of a handrim into the unidirectional output motion of a wheel. A main feature of the forward. backward propulsion is to supply continuous driving torque without break. Motion. analysis has been performed through 2-dimensional image processing for measuring the kinematic properties of the upper arm and fore arm. Then, the inverse dynamics analysis has been done for obtaining the joint torques, the handrim forces and input/output powers. Results show that the output power by the forward. reverse propulsion is almost twice as much as that by conventional propulsion. Also, the new propulsion is expected to reduce the fatigues and injuries at arm joints by employing more muscle groups for movement. In conclusion, the forward. reverse propulsion can greatly improve the performances of manual wheelchairs by providing better mobility as well as by guaranteeing several advantages from a biomechanical viewpoint. Future development of a manual wheelchair optimized for the bi-directional propulsion will further improve the propulsion performances.

• Journal of Urban Science
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• v.10 no.1
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• pp.1-10
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• 2021

The purpose of this study was to evaluate accessibility condition of buildings in a college from manual wheel chair users' perspective in order to suggest improvements, and to develop 3D accessibility maps in order to assist manual wheelchair users' prior planning for the building use. In May 2020, on-site investigation was held to three buildings in Chungbuk National University. Major findings were as follows. (1) There were some building entrances that showed level difference over 2cm without proper ramp with slow slope 1/8 or less. (2) Some rooms were found to have accessibility issues to have floors with height more than 2cm, and/or to have no height-adjustable desks. (3) Although accessible restrooms were in good condition for manual wheelchair users' access and use, it is suggested to install accessible restroom for each gender in each floor for better access. Using the study results, 2-dimensional accessibility maps for each floor were developed in color and grayscale, which were further developed into 3-dimensional accessibility maps for each building.

• Journal of the Korean housing association
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• v.28 no.2
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• pp.23-33
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• 2017

This study was aimed to assess accessibility situation of pedestrian environment of University-C focusing on accessibility of manual wheelchair users and to develop accessibility campus map. During March and April 2016, barrierfree design application situation of pedestrian environment and building entrances were investigated using a structured checklist and a digital distance and slope meter. Major findings are as follow. (1) Except one case, widths of all pedestrian routes (both sidewalk and non-sidewalk routes) exceeded 2 meters. (2) As for sidewalk and driveway contact point condition, there were many spots lacking curb ramp or alterative ramp that are accessible for manual wheelchair users. (3) More than half of non-sidewalk pedestrian routes did not have bollard to separate pedestrian and vehicle flows, and more than 92% of the bollards installed were too close for wheelchair users to pass or too far to prevent vehicle access. (4) More than 59 percent of the building entrances were found impossible for manual wheelchair users to access without any assistance, and one third of the buildings did not have any single accessible entrance. Based on the study findings, campus accessibility map was developed by the researchers and disseminated through university homepage. Using the campus accessibility map, users can plan their accessible paths ahead the trip.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.7 no.1
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• pp.21-27
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• 2013

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.

• Journal of Biomedical Engineering Research
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• v.43 no.4
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• pp.241-250
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• 2022

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 (G_E) and 27 healthy adults for the control group (G_C) participated in this study. Joint angles and electromyography were measured while subjects performed self-selected comfortable 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 G_E; 20.24 deg in G_C) and elbow (5.25 deg in G_E; 2.57 deg in G_C) 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. Specifically, triceps brachii showed a significant increase in muscle activation at fast propulsion. AHD decreased at fast propulsion. Moreover, the AHD of G_E was already narrowed by about 60% compared to the G_C 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.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.3 no.1
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• pp.1-6
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• 2009

In this paper, when wheelchair user get into the vehicle, we have thorough grasp of the problems of loading wheelchair and give effect to suggest conceptual design in relation to develop manufactured goods. We choose 50 participants with disabilities who manual wheelchair or motor scooter users are able to drive own's vehicle, and the method practice in the direct survey. There are some limitations in this study especially in terms of the sampling population. The 88%(n=44) of the participant replied to the driver with disabilities need assistive devices for loading manual wheelchair. They prefer a system that robot arm brings the wheelchair out of the trunk to the driver's seat door.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.22 no.3_1spc
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• pp.580-586
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• 2013

In general, manual wheelchairs have played important roles in moving patients from one place to another. However, patients have experienced discomfort getting on and off because of the need for physical assistance. This can be more serious if a patient has handicaps involving the arms or legs. In addition, it could be unpleasant for both the patient and assistant because of the need for extensive physical contact with each other. At times, a weak nurse feels that there is a risk when transferring a heavy patient from a bed to a wheelchair. In this paper, a new non-powered wheelchair is designed to assist in transferring a patient to their bed. This design considers the convenience of both the patient and assistant when the patient is transferred from a wheelchair to a bed and vice versa. The operation minimizes the physical contact between the assistant and the patient. The new wheelchair is also lightweight and portable compared with the normal popular wheelchair.