• Proceeding of EDISON Challenge
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• 2016.03a
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• pp.516-517
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• 2016

I use Jansen mechanism to reduce the unnecessary motion of car body and improve the motion performance capability in the rugged terrain To reduce the unnecessary motion, the positional variation of a main body of vehicle should be minimized. In order to reduce the change of height and control the speed at every moment when vehicle move, 16 legs or more are installed on a crankshaft and the paths of leg motions need to be considered in the rugged terrain. The vehicle will be optimized so that it produces a sufficient speed and torque for practical use. Finally, I designed proper body with Edison simulation. The simulation is good for beginners of mechanism design.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.49 no.10
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• pp.637-645
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• 2000

This study was represented the improvement of the flexible position control for linear motion of hybrid type linear pulse motor(HLPM). The driving method used a minute 125 microstep drive instead of full step drive method. The digital control method was applied to the PI control for more stable position control, at this time the PI control parameters have gained by a Ziegler-Nichols turning method. The loop transfer function of control system was combined with both motor transfer function and digital PI control equation. Such, the proper for digital PI control system is verified to through the simulation and experimental result of the stability step response and bode plot with proper gain and phase margin.

• Korean Journal of Applied Biomechanics
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• v.20 no.3
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• pp.311-318
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• 2010

This study examined the double piked dismount among the landing techniques of parallel bars based on three-dimensional motion analysis. Four male national gymnasts were the subjects. This study was performed to provide quantitative data highlighting players strengths and weaknesses to enable more stable landing technique. The variables analyzed were the position and velocity of center of gravity(CG) and angles of shoulder joints, hip joints, and trunk. The results are as follows: S1 secured the height of flight with fast vertical rise. After the easy spin in the air, he conducted a stable landing maintaining a proper hip joints angle. S2, S3, and S4, however, began the backward somersault already before leaving the bars, so they moved backward greatly making it more difficult to achieve a higher flight path. As a result, they couldn't control the velocity of their backward movement at landing. For a stable landing, they have to maintain the negative shoulder angle when rising, minimize both antero-posterioror side-to-side movements by doing a strong tap using hip joints, to secure the height of flight before the somersault. Results also show that at the descent, they should conduct rapid spinning by increasing their shoulder and hip joints to the maximum while controlling their velocity.

• International Journal of Control, Automation, and Systems
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• v.6 no.4
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• pp.551-558
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• 2008

This paper deals with the real-time stable walking for a humanoid robot, ISHURO-II, on uneven terrain. A humanoid robot necessitates achieving posture stabilization since it has basic problems such as structural instability. In this paper, a stabilization algorithm is proposed using the ground reaction forces, which are measured using FSR (Force Sensing Resistor) sensors during walking, and the ground conditions are estimated from these data. From this information the robot selects the proper motion pattern and overcomes ground irregularities effectively. In order to generate the proper reaction under the various ground situations, a fuzzy algorithm is applied in finding the proper angle of the joint. The performance of the proposed algorithm is verified by simulation and walking experiments on a 24-DOFs humanoid robot, ISHURO-II.

• Clinics in Shoulder and Elbow
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• v.18 no.2
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• pp.105-112
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• 2015

In orthopedic trauma surgery, treatment of intraarticular distal humerus fractures is a challenge. With development of implants and biomechanical studies, surgical strategies with recommendations including preoperative computed tomography images, proper approaches and open reduction and internal fixation with dual plates have emerged. In addition, as an effort to provide stable fixation to permit early elbow motion, different methods of internal fixation, particularly plate configuration, have evolved. Using dual plates, either oriented parallel to each other or orthogonal, stable fixation has been achieved and satisfactory clinical outcomes have been reported. With rationales and advantages/disadvantages of each plate configuration, both techniques are selected according to surgeons' preference, and, in specific cases, one could be preferred over another. The key to successful fixation by either technique is obtaining anatomical reduction with restoration of two stable columns of the distal humerus.

• 제어로봇시스템학회:학술대회논문집
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• 1990.10a
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• pp.731-735
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• 1990

The mobile robot, named as KAEROT, is designed to go up and down stairs in nuclear facilities. To get a proper stable motion, kinematic modeling and analysis are seriously considered and new climbing algorithm is proposed focused on the stability. A couple of small wheels of one planetary wheel have to contact the surface ol stairs all the time to give the guarantee for stability and safety. To confirm the validity of the proposed algorithm, simulation is carried out. The results make evident of feasibility for the algorithm.

• Clinics in Shoulder and Elbow
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• v.19 no.1
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• pp.43-47
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• 2016

Many types of osteotomy have been proposed for the treatment of cubitus varus deformity of the elbow, and various methods for fixation of the osteotomy site have also been described. However, no method has been perfect. We treated two cases of cubitus varus elbow deformity with step-cut osteotomy using a new fixation method with two crossing screws and an anatomically designed locking plate. Active assisted elbow range of motion (ROM) exercise was permitted at postoperative 3 days, after removal of the drainage. Preoperative and postoperative humerus-elbow-wrist angles and ranges of motion of the two patients were compared. At 3 months followup, each patient had recovered the preoperative elbow ROM, and achieved the complete bony union of the osteotomy site and proper correction of the cubitus varus deformity. In addition, the appropriate remodeling of the lateral bony protrusion was observed. Therefore, we introduce a new fixation method for achievement of stable fixation allowing immediate postoperative elbow motion after corrective osteotomy for cubitus varus deformity in young adults.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.12C
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• pp.1209-1216
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• 2003

The transcoding is needed to modify the bit rate of the video bitstream in accordance with the bandwidth of a variety of channels in order to provide users with a realtime multimedia service and more stable and credible VOD(Video On Demand) service on various wire/wireless network. This paper suggests how to guarantee the video quality in the transcoding process, taking the activity and direction of the macroblock into consideration, thereby reducing the calculation. The threshold of the macroblock's activity and direction is applicable to the different videos, with the DCT coefficients from the intermediate data in the decoding process. Moreover, the suggested video transcoding algorism enables us to maintain the proper video quality and reduce the calculation through the video bit rate change experiment in H.263 environment.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.1780-1783
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• 2005

In this paper ZMP was considered in order to get a walking stability, so the gait in the stable domain was realized through putting the stability margin in the sole domain of a foot. It is assumed that the robot's legs have 12 joints to operate a open-loop drive and there was no external disturbance under walking phases, additionally, the robot is walking on the flat plane. It was observed that the robot's walking trajectory, locus of COM and ZMP after imposing the motion to each joint. For realizing the simulation considering ZMP and movement of mass center, it was checked if it is stable for the constraint robot model to walk in stability and the feasibility was estimated about its dynamic gait. Eventually it was shown that a constraint gait algorithm is able to realize. To verify the proper walking process, ZMP(Zero Moment Point) theory is applied and the simulation has been done by ADAMS.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• v.11B no.2
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• pp.28-33
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• 2001

The subject of this study is to improve the position performance of the linear motion for hybrid type Linear Pulse Motor (HLPM). Generally, there are two applicable methods to ensure precise position control ; a good processing method. This paper is suggested an electrical 125 microstep driving method so as to achieves the excellent control performance, besides the small mechanical manufacture of teeth pitch. The compensation method of digital PI control is apply to step response of stable position control, step error, vibration suppression and the approach to high stability, and the Ziegler-Nichols tuning method is applied to the proper design of control parameter. The proposed control method has been verified by simulation results of the suitable gain and phase margin of bode plot, and from experiment result of step response.