• Journal of IKEEE
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• v.26 no.2
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• pp.249-256
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• 2022

The prosthetic leg is a device that performs walking instead of a amputated lower limb, and require a change in locomotion mode by providing the user's intention to respond to a discontinuous locomotion environment. Research has been conducted to detect the users' intentions through biomechanical features inside the socket that directly contacts the cut site in demand for natural locomotion mode changes without external control equipment. However, there is still a need for a sensor system that is suitable for the internal environment of the main body and socket of the cut site. Accordingly, this paper proposed a film-type sensor system that is suitable for the main body characteristics of the cut site, is not affected by the temperature and humidity conditions inside the socket, and is easy to manufacture in various sizes. The proposed sensor is manufactured base on Velostat film and takes into account the pressure measurement characteristics that vary with size. Through the experiment, the change in the internal pressure of the socket due to the intentional posture performance of the wearer was measured, and the possibility of detecting the intention to change the locomotion mode was confirmed.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2007.04a
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• pp.7-10
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• 2007

This paper presents a fuzzy footstep planner for humanoid robots in complex environments. First, we define locomotion primitives for humanoid robots. A global planner finds a global path from a navigation map that is generated based on a combination of 2.5 dimensional maps of the 3D workspace. A local planner searches for an optimal sequence of locomotion primitives along the global path by using fuzzy footstep planning. We verify our approach on a virtual humanoid robot in a simulated environment. Simulation results show a reduction in planning time and the feasibility of the proposed method.

• ETRI Journal
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• v.36 no.1
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• pp.99-105
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• 2014

This paper presents a new locomotion mode recognition method based on a transformed correlation feature analysis using an electromyography (EMG) pattern. Each movement is recognized using six weighted subcorrelation filters, which are applied to the correlation feature analysis through the use of six time-domain features. The proposed method has a high recognition rate because it reflects the importance of the different features according to the movements and thereby enables one to recognize real-time EMG patterns, owing to the rapid execution of the correlation feature analysis. The experiment results show that the discriminating power of the proposed method is 85.89% (${\pm}2.5$) when walking on a level surface, 96.47% (${\pm}0.9$) when going up stairs, and 96.37% (${\pm}1.3$) when going down stairs for given normal movement data. This makes its accuracy and stability better than that found for the principal component analysis and linear discriminant analysis methods.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.05a
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• pp.883-889
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• 2005

Micro robots have been developed for many applications: medical, industrial, military, and so on. A small mobile robot was built and it has three legs made of bimorph piezoelectric actuators. It proceeds by vibrating the rear leg and it rotates by vibrating one of the front legs. The locomotion of the robot is described by relative position of mass center and the friction between the legs and the floor. This paper describes the principles of locomotion and modeling of the robot Modeling was simulated to investigate the dynamics of its mobility. The simulation results verified the modeling by showing similar movement of the robot as measured. It remained, however, several problems through experiments such as crooked direction of forward movement and proceeding speed.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.435-440
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• 2007

Fish-mimetic robots or fish-mimetic propulsors have been developed or under construction. A mechanical system cannot have the same functions as bio-organic systems. Thus, the hydrodynamic characteristics of fish locomotion should be well understood in order to develop and control a feasible intelligent fish-mimetic robot with its optimal motion pattern known. In this paper, a mackerel-mimetic robot fish is fabricated in order to understand the hydrodynamic characteristics of fish locomotion. A simplified unsteady flow theory is also applied to the hydrodynamic analysis of the motion of the anterior part of the robotic fish. The normal and axial forces of the fish are measured by changing the amplitude and frequencies of fanning motion. It is found that the present theoretical results agree with the measured data.

• Journal of Biomedical Engineering Research
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• v.15 no.1
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• pp.27-34
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• 1994

In this paper. a way to analysis a corridor scene for a vehicle's automatic locomotion is presented In general, it's necessary for a vision system of vehicles to identify its positions in given environments. The suggested algorithm is to decide base lines of a corridor image using the vanishing point finding. Feature points are extracted on the base line using a base line extraction tree. This algorithm is suitable for a motorized wheelchair's self locomotion in a building.

• Journal of Biomedical Engineering Research
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• v.10 no.2
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• pp.109-111
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• 1989

An electrical stimulator was designed to induce locomotion for paraplegic patients caused by central nervous system injury. Optimal stimulus parameters, which can minimize muscle fatigue and can achieve effective muscle contraction were determined in slow and fast muscles in Sprague-Dawley rats. Stimulus patterns of our stimulator were designed to simulate electromyographic activity monitored during locomotion of normal subjects. Muscle types of the lower extremity were classified according to their mechanical property of contraction, which are slow muscle (msoleus m.) and fast muscle (medial gastrocneminus m., rectus femoris m., vastus lateralis m.). Optimal parameters of electrical stimulation for slow muscles were 20 Hz, 0.2 ms square pulse. For fast muscle, 40 Hz, 0.3 ms square pulse was optimal to produce repeated contraction. Higher stimulus intensity was required when synergistic muscles were stimulated simultaneously than when they were stimulated individually. Electrical stimulation for each muscle was designed to generate bipedal locomotion, so that individual muscles alternate contraction and relaxation to simulate stance and swing phases. Portable electrical stimulator with 16 channels built in microprocessor was constructed and applied to paraplegic patients due to lumbar cord injury. The electrical stimulator restored partially gait function in paraplegic patients.

• Proceedings of the KIEE Conference
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• 1987.07b
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• pp.1260-1263
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• 1987

This paper describes the mobile robot system to recognize the guidance tape, and presents the locomotion algorithm. This system converts video imago to binary image by setting an optimal threshold and obtains the parameters to move the robot. The mobile robot moves according to the programmed route in memory. But after recognized the obstacle on the locomotion routs, this system constructs the new route and the robot moves following the new route.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.658-663
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• 2005

This paper presents the steering control algorithm of a locomotion robot using a quaternion. The locomotion robot is to be moved on an irregular floor that can inevitably result in the errors of both position and orientation. Especially the orientation error should be compensated every work in order to adjust the misaligned values of current orientation to those commanded values. In this paper, we propose a new steering control algorithm between the two values by using a quaternion with spherical cubic interpolation. The proposed algorithm is shown to be effective in terms of vibration when compared to a conventional simple compensation without interpolation, by using $MATLAB^{(R)}$ and $VisualNastran4D^{(R)}$.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.2211-2216
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• 2005

This paper describes a novel navigation algorithm using a locomotion interface with two 6-DOF parallel robotic manipulators. The suggested novel navigation system can induce user's real walking and generate realistic visual feedback during navigation, using robotic manipulators. For realistic visual feedback, the virtual environment is designed with three components; 3D object modeler for buildings and terrains, scene manager and communication manager component. The walking velocity of the user is directly translated to VR actions for navigation. Finally, the functions of the RPC interface are utilized for each interaction mode. The suggested navigation system can allow a user to explore into various virtual terrains with real walking and realistic visual feedback.