• Transactions of the Korean Society of Machine Tool Engineers
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• v.18 no.2
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• pp.154-161
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• 2009

In order to implement continuous-path motion on a robot, it is necessary to blend one joint motion to another joint motion near a via point in a trapezoidal form of joint velocity. First, the velocity superposition using parametric interpolation is proposed. Hybrid motion blending is defined as the blending of different two type's motions such as blending of joint motion with linear motion, in the neighborhood of a via point. Second, hybrid motion blending algorithm is proposed based on velocity superposition using parametric interpolation. By using a 3-axis SCARA (Selective Compliance Assembly Robot Arm) robot with $LabVIEW^{(R)}$ $controller^{(1)}$, the velocity superposition algorithm using parametric interpolation is shown to result in less vibration, compared with PTP(Point- To-Point) motion and Kim's algorithm. Moreover, the hybrid motion $algorithm^{(2)}$ is implemented on the robot using $LabVIEW^{(R)(1)}$ programming, which is confirmed by showing the end-effector path of joint-linear hybrid motion.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.1A
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• pp.51-57
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• 2002

In this paper, a simple interpolation technique in a frequency domain is proposed for the discrete Fourier transform(DFT) algorithm. Frequency and phase resolution capabilities of the DFT algorithm can be significantly improved by the proposed interpolation technique without increase of a DFT size(the number of points for the DFT). The new technique uses a diving point in amplitude and phase spectrums. As an application, the technique can be used for joint estimation of fine frequency and phase offsets in burst mode digital transmission. Simulation results show that the joint estimator using the technique is robust to estimation errors.

• Journal of the Korean Institute of Telematics and Electronics
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• v.24 no.5
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• pp.753-761
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• 1987

Approximation of a Cartesian straight line motion with linear interpolation in the joint space has many desirable advantages and applications. But inappropriate determination of the corresponding subtravelling and transition times makes such joint-trajectories violate the input torque/force constraints. An approach that can overcome this difficult and yield the joint trajectories utilizing the allowable maximum input torque/force is established in this paper. The effectiveness of these results is demonstrated by using a three-joint revolute manipulator.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.35 no.6
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• pp.343-349
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• 2022

This paper proposes a new topology optimization scheme to determine optimized joints for multi-component models. The joints are modeled as zero-length high-stiffness spring elements. The spring joints are considered as mesh-independent springs based on a joint-element interpolation scheme. This enables the changing of the location of the joints regardless of the connected nodes during optimization. Because the joints are movable, the locations of the optimized joints should be aggregated at several points. In this paper, the novel joint dispersal (JD) constraint to prevent joint clustering is proposed. With the joint dispersal constraint, it is possible to determine the optimized joint location as well as optimized topologies while maintaining the minimum distance between each joint. The mechanical compliance value is considered as the objective function. Several topology optimization examples are solved to demonstrate the effect of the joint dispersal constraint.

• Proceedings of the IEEK Conference
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• 2002.06e
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• pp.121-124
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• 2002

This paper explains the system which finds the data of the joint of Wire Frame(that express the body structure of the golfer) from standard golf swing movie. Also, this paper used interpolation and the method which modify the distance between a joint and a close joint to general new joint data. Last this paper explains the system that make a standard golf swing attitude by continuous display the static attitude(which are formed with Wire Frame) of golf swing operations.

• Proceedings of the KIEE Conference
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• 1989.11a
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• pp.445-449
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• 1989

Achievement of a straight line motion in the Cartesian space has a matter of great importance. Minimization of task execution time with linear interpolation in the joint space, accomplishing of a approximation of straight line motion in the Cartesian coordinate is considered as the prespecified task. Such determination yields minimum time joint-trajectory subject to input torque constraints. The applications of these results for joint-trajectory planning of a two-link manipulator with revolute joints are demonstrated by computer simulations.

• 제어로봇시스템학회:학술대회논문집
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• 1990.10b
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• pp.913-916
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• 1990

In this paper, attempts have been made to control AC synchronous servo motor used as actuators of joints of the FARA robot with high dynamic performance and precise positioning. The AC synchronous servo motors used in FARA robots have resolves as position sensors. Resolver to digital converters are used in order to obtain the information of rotor speed and position from resolver outputs. The proposed joint position control system consists of four speed controller and one position controller. Analog methods are used in the position controller, while digital methods are used in the position controller. For precise position control, PID control algorithm and interpolation functions are executed in two 16 bit microprocessors with sampling rate 2ms. Experimental results show that the proposed joint position control system can be effectively applied to industrial robots in order to obtain high dynamic performance and precise positioning. The proposed joint position control system is being used in the control of FARA robots of Samsung Electronics.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.4
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• pp.2370-2378
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• 2015

This paper proposes an algorithm using Lagrange interpolation method to realize trajectory planning for torque minimization of robot manipulators. For the algorithm, position constraints of robot manipulators should be given and the stability of robot manipulators should be satisfied. In order to avoid Runge's phenomenon, we set up time interpolation points using Chebyshev interpolation points. After that, we found suitable angle which corresponds to the points and then we got trajectories of joint's angle, velocity, acceleration using Lagrange interpolation method. We selected performance index for torque consumption optimization of robot manipulator. The method went through repetitive computation process to have minimum value of the performance index by calculated trajectory. Through the process, we could get optimized trajectory to minimize torque and performance index and guarantee safety of the motion for manipulator performance.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.49 no.1
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• pp.58-66
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• 2012

Even after establishment of H.264/AVC standard, the video coding experts group (VCEG) of ITU-T has researched on development of promising coding techniques to increase coding efficiency based on the key technology area (KTA) software. Recently, the joint collaboration team video coding (JCT-VC) which was composed of the VCEG and the motion picture experts group (MPEG) of ISO/IEC is developing a next-generation video standard namely HEVC intended to gain twice efficiency than H.264/AVC. An adaptive interpolation technique, one of various next-generation techniques, reported higher coding efficiency. However, it has high computational complexity and does not deal with various error characteristics for videos. In this paper, we investigate characteristics of interpolation filters and propose an effective fixed interpolation filter bank including diverse properties of error. Experimental results is shown that the proposed method achieved bitrate reduction by 0.7% and 1.3% compared to fixed directional interpolation filter (FDIF) of the KTA and the directional interpolation filter (DIF) of the HEVC test model, respectively.

• Journal of Advanced Navigation Technology
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• v.11 no.2
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• pp.209-216
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• 2007

In this paper, we embodied posture-stabilization and dynamic gait in a walking robot. 10 RC servo motors are used to operate joints. And the joints have enough moving ranges suitable in any walking pattern. Each joint trajectory is generated by cubic spline interpolation method and the stability of the trajectory is verified by using Zero Moment Point from the robot modeling. To avoid complex structure and expression, Zero Moment Point of the biped robot used angular acceleration is suggested. To measure the stability of the biped robot, Tilt sensor and gyro sensor are used. Finally, Personal Computer is used computer monitoring and data processing. Most of computation, such as 10 RC servo motor control, joint trajectory generating, ZMP compensation, sense measuring, etc, was used Digital Signal Processor.