• Transactions of the Korean Society of Machine Tool Engineers
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• v.16 no.5
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• pp.1-6
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• 2007

This paper presents a new experimental Servo-Parameter tuning technique for a 6-axes articulated robot manipulator, especially considering robot's dynamics. First of all, investigation for proportional gain of velocity control loop by using a Dynamic Signal Analyzer(DSA) is performed. Using the FUNCTION characteristic of DSA based on the Bode plot, the Bode plot of open loop transfer function can be obtained. In turn, the integral gain of a servo controller can be found out by using the integration time constant extracted from the Bode plot of open loop transfer function. In the meanwhile, the positional gain of the servo controller can be obtained by using the Bode plot of the closed loop transfer function. Using the experimental gain tuning technique proposed in this paper, the testing linear motion of DR6-II robot has been shown to be more accurate rather than the motion with a conventional(empirical) gain tuning technique in Doosan Mecatec Co., Ltd., by improving the dynamic response of the robot as well as synchronizing each joint velocity according to the positional command of an end-effector.

• Journal of the Korea Society of Computer and Information
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• v.20 no.4
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• pp.33-40
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• 2015

This paper presents the design and implementation of the educational remote controlled robot system including remote sensing in the embedded environment. The design of sensing information processing, software design and template design mechanism for the programming practice are introduced. LPC1769 using Cortex-M3 core as CPU, LPCXPRESSO as debugging environment, C language as firmware development language and FreeRTOS as OS are used in development environment. The control command is received via RF communication by the server and the robot system which is operated by driving the various sensors. The educational procedure is from robot demo operation program as hands-on practice and then compiling, loading of the basic robot operation program, already supplied. Thereafter the verification is checked by using the basic robot operation to allow demo operation such as hands-on-training procedure. The original protocol is designed via RF communication between server and robot system, and the satisfied performance result is presented by analyzing the robot sensing data processing.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.43 no.6
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• pp.497-506
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• 2015

A composite guidance law for impact angle control against nonstationary nonmaneuvering targets is proposed. The proposed law is based on the characteristics of proportional navigation and generates two kinds of guidance commands during the homing phase. The first command is to keep the desired look angle, and the second is to attack the target with impact angle constraint. The switch of guidance phases occurs when the specific light-of-sight(LOS) angle determined from the engagement information is satisfied. The calculation method of the maximum achievable impact angle is also proposed to design easily the desired impact angle within the missile capability. Numerical simulations are performed to investigate the performance and characteristics of the proposed law.

• Journal of Biomedical Engineering Research
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• v.16 no.4
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• pp.543-554
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• 1995

This paper describes the improvement of driving stability and the control system for INMEL-VII which is motorized manual wheelchair to satisfy requirements of the disabled The INMEL-VI was based on high maneuverability of the omnidirection drive and safety But the results of field tests about two years showed some problems to the disabled in daily life such as driving stability, Pm switching noise, and rotation of motor without driving command on negative slope. To solve the problems due to an increased DC motor power and applied to direct connection method in INMEL- VII. It improved the driving circuits and set switching frequency to 5KHz to eliminate the switching noise caused by PWM control of DC motor, As compare with the INMEL-VI, INMEL-VII is improved in driving stability by transfer the weight center to forward. The results of field testing proved the improvement of the driving stability and software algorithm It has been estimated to have a hlgh practical use for powered walking aids to the disabled's daily life.

• Journal of the Korean Society of Propulsion Engineers
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• v.18 no.3
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• pp.8-16
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• 2014

This paper analyzes the effects of sideslip angle(SA) on the buzz margin of supersonic intake. The buzz margin is assumed to be stabilized by a controller which generates command depending only on the longitudinal sensor measurements. The analysis is performed based on three dimensional CFD results with which the sensor measurements can be simulated. In such a control system based on the longitudinal measurements, unexpected lateral flow perturbation results in the increase in the total angle of attack(TAoA), that causes the degradation of the engine intake performance. As a consequence, it is shown that the control stability is reduced such that additional control margin needs to be secured.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.44 no.3
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• pp.51-57
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• 2007

Without human dynamics effects, the manually operated target tracking system has poor performance or instability in real environments. The tracking system is invalid when a human is added to the control loop as a real time delay, because input signals are generated by human operator to reduce the errors between target and gun. In this paper, we consider the human operator as a part of controller and modeling the human operator as a first-order model to generate the intentional force. But it is known that human modeling is not easy because of disturbance or noise of the vehicle while moving for the target. We performed a variety of experiments with real plant to identify the model's parameters and verify the proposed operator model's efficiency.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.44 no.4 s.316
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• pp.67-73
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• 2007

An optical pick up generally has coupled dynamics between focusing and tracking servos. The coupled dynamics reduces tracking performance of optical disk drives. A conventional control method is holding the previous tracking control command in the presence of surface defect. The method has a long settling time. If the defective area is getting larger, objective lens will get away from the following track. In order to overcome this problem, this paper proposed a new control method for optical disk drives based on a prediction of tracking error and focusing error. We present how to compensate the coupled dynamics so that reduced setting time is achieved. It is verified by experiments that the proposed method brings an improved performance in the presence of surface defect as well as in the normal operating condition.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.17 no.11
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• pp.1219-1227
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• 1992

VXIbus is a standard for compatibility of instruments of multi-vendors and originated from the VMEbus. The devices for implementing VXIbus system can be categorized into the register based device and the message based device. In this paper we organized the A/D conversion module and the slot0 module, which form the register based VXIbus subsystem. The A/D conversion module is used as a digital voltmeter and LAN is used for communication between an external control computer and the slot0 module. The SCPI(Standard Commands for Programmable Instruments), which is a standard language for instruments, is transmitted from the external control computer to the slot0 module as the ASCII form, and then to the A/D conversion module after changing to the binary digit command. From the experiment. We verified that the measured voltage can be observed on external control computer and user interface can be improved by the modified graphic processing.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.13 no.5
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• pp.452-459
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• 2020

The electric actuator receives the user's command input signal (open/closed/stop), checks the status of various sensors (valve position, rotational force, motor status, etc.)in the actuator, and controls the motor forward/reverse to open and close the valve. It is a device that outputs the current state of an actuator (valve) and is used in various fields such as dams, power plants, water and sewage facilities, and oil pipeline facilities. If an electric actuator is installed in a power plant and a problem occurs during operation, it can cause a large economic loss, so system reliability is vert important. In this study, in order to increase the safety of the electric actuator, the development of an electric actuator control device capable of setting the ON/OFF time in hardware was conducted to solve the reliability problem that may occur in software. In addition, the electric actuator control device development environment was developed using Xilinx's Spartan7 FPGA and Altium tool.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.1
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• pp.1-7
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• 2012

This paper introduces the mechanical design, fabrication, and control of a biomimetic fish robot whose driving motions resemble a real fish's flexibility and movement. This robot uses two motors create flexible movement like that of a fish. Several schemes, such as neutral buoyancy, fast underwater swimming, and direction changes, are introduced. The tail of the fish robot is made of a polymer material for flexible movement. The interior of the tail contains a joint and a wire. A sine wave command was applied to the tail to produce motion resembling a real fish swimming, and a buoy control device was installed. The up and down motion of the robot fish was controlled using this device.