• Journal of the Korean Society for Precision Engineering
• /
• v.28 no.11
• /
• pp.1265-1271
• /
• 2011

These days the number of aged and disabled people is increasing rapidly. But most of the disabled or the aged who have the ability to work, want to engage in economic activities and solve social restrictions as well as their bad financial conditions. This paper concerns about the tracking control of an electric wheelchair robot for welfare vehicle where the seat and electric wheelchair are separated and electric wheelchair robot must be autonomously controlled without the help of assistant. So the aged or the disabled people can drive welfare vehicle by himself by adopting this system. Therefore the concept of both an autonomous driving of electric wheelchair and path tracking robots is required in this system. Finally we suggested fuzzy controller in order to control the path tracking of electric wheelchair robot and compared the capability of the proposed controller with conventional PID controller.

• Journal of Internet of Things and Convergence
• /
• v.10 no.2
• /
• pp.69-75
• /
• 2024

This paper proposes an IoT-based indoor autonomous driving system that applies SLAM (Simultaneous Localization And Mapping) and Navigation techniques in a ROS (Robot Operating System) environment based on TurtleBot3. The proposed autonomous driving system can be applied to indoor autonomous wheelchairs and robots. In this study, the operation was verified by applying it to an indoor self-driving wheelchair. The proposed autonomous driving system provides two functions. First, indoor environment information is collected and stored, which allows the wheelchair to recognize obstacles. By performing navigation using the map created through this, the rider can move to the desired location through autonomous driving of the wheelchair. Second, it provides the ability to track and move a specific logo through image recognition using OpenCV. Through this, information services can be received from guides wearing uniforms with the organization's unique logo. The proposed system is expected to provide convenience to passengers by improving mobility, safety, and usability over existing wheelchairs.

• Journal of rehabilitation welfare engineering & assistive technology
• /
• v.10 no.2
• /
• pp.133-139
• /
• 2016

An electric wheelchair is a assistive device to maneuver on the ground. Tip-over of an electric wheelchair is increasing every year. Dynamic stability metric test item in KS P 7176 has not ensured safety of electric wheelchair on the slope. This study presents design the foldable electric wheelchair that can load in the car and analysis of tip-over measurement which is easily computed for electric wheelchair. Wheelchair frame is designed with a four-bar link mechanism for a foldable structure, and seat module, battery and power driving module can be separated. This analysis is performed during a maneuver on the ground by force-moment stability metric. Several elements, center of gravity position, rotational radius and acceleration, were evaluated how to affect stability metric. This stability metric can reduce tip-over of wheelchair and provide a clue to make of dynamic stability test item.

• Journal of Institute of Control, Robotics and Systems
• /
• v.22 no.7
• /
• pp.552-556
• /
• 2016

Obstacle detection is a key feature in the safe driving control of electric wheelchairs. The suggested obstacle detection algorithm was designed to provide obstacle avoidance direction and detect the existence of cliffs. By means of this information, the wheelchair can determine where to steer and whether to stop or go. A 3D depth camera (Microsoft KINECT) is used to scan the 3D point data of the scene, extract information on obstacles, and produce a steering direction for obstacle avoidance. To be specific, ground detection is applied to extract the obstacle candidates from the scanned data and the candidates are projected onto a 2D map. The 2D map provides discretized information of the extracted obstacles to decide on the avoidance direction (left or right) of the wheelchair. As an additional function, cliff detection is developed. By defining the "cliffband," the ratio of the predefined band area and the detected area within the band area, the cliff detection algorithm can decide if a cliff is in front of the wheelchair. Vehicle tests were carried out by applying the algorithm to the electric wheelchair. Additionally, detailed functions of obstacle detection, such as providing avoidance direction and detecting the existence of cliffs, were demonstrated.

• Journal of rehabilitation welfare engineering & assistive technology
• /
• v.6 no.1
• /
• pp.9-15
• /
• 2012

In this paper, the feasibility of a wheelchair carrier for the disabled own driver is checked kinematically to fit one of current domestic vans by drawings, design. A van with 9 passengers is selected for the modification to attach the wheelchair carrier and test the operation in real situation. The trajectory and motion process are studied to protect from the interception with outside body of van, and the conceptual design is proceeded kinematically. For the detail design, the stress analysis and driving mechanism with power supply must be studied and selected basically.

• Journal of the Ergonomics Society of Korea
• /
• v.27 no.3
• /
• pp.23-32
• /
• 2008

This study attempts to develop improved ingress and egress in vehicle for disabled wheelchair people who driving is available, after investigating the ingress and egress relation demand and the inconvenient factor in the vehicle. An experiment was performed for that disabled wheelchair people to analyze the characteristics of ingress and egress relation operation through the questionnaire survey and the camera photographing. The results suggest various improvements possibilities in inside handlebar as a main factor. Through analysis of disabled wheelchair person's ingress and egress tendency, the alternative shape and position of inside handlebar are suggested. Also, this paper aimed to draw ingress and egress improvement proposal by executing a verification experiment and collecting the preferences from disabled people.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2013.05a
• /
• pp.1395-1396
• /
• 2013

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.21 no.12
• /
• pp.857-866
• /
• 2020

'Movement' is an expanded concept of 'place' where people act, interact with one another and achieve a specific purpose at every moment. Wheelchairs, as a mobility aid, have a profound impact on improving the quality of physical and psychological well-being for the mobility disadvantaged groups who have mobility difficulties. Such mobility aids were developed mainly for outdoor activities, but in recent years, mobility aids for indoor spaces, the main living environment, are also being developed. Because indoor mobility aids generally move short distances repeatedly, this study examined the characteristics of lithium-ion batteries in short-distance driving of battery-powered wheelchairs and compared them with the characteristics of lithium-ion batteries in continuous driving. The result showed that the driving time for short-distance driving was 2.8% shorter than that of continuous driving. The current supplied to the motor was 15.4% higher for short-distance driving than that of continuous driving.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.12 no.8
• /
• pp.3360-3365
• /
• 2011

This paper deals with method to measure the user's driving-will force and to control the power-assisted wheelchair. To solve this problem, we extract the user's driving-will by using the mathematical motor model. And then, we get the linear and angular velocity at the center of the vehicle. Wheel velocities are also measured from center velocity. Finally, power-assisted electric wheelchairs are controlled by these data. Here all processes are verified by simulation.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.21 no.11
• /
• pp.851-860
• /
• 2020

With an increase in the aging population and a rising social interest in health and welfare, studies to improve healthcare in the elderly are being actively conducted. This study attempted to improve the current design and manufacture of elevating electric wheelchairs to enhance user safety and convenience. Seat design based on the user's body shape, convenience while boarding or alighting, caster turning radius and, safety and stability features that prevent shaking when the user gets up or sits down were improved. A driving experiment was conducted to evaluate the operation of the indoor electric wheelchair designed and manufactured with these additional functionalities. During the test, the performance parameters evaluated were continuous driving time, turning radius, maximum lifting and lowering load, maximum lifting height, noise level, minimum distance sensing by the driving auxiliary sensor, ability to interact with server and app programs, and the duty cycle maximum error rate. The test confirmed that this improved electric wheelchair successfully met target parameters. In a future study, we will evaluate this improved electric wheelchair from a user's perspective for its usability parameters, such as satisfaction, convenience and stability.