• Journal of the Korea Institute of Military Science and Technology
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• v.17 no.5
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• pp.703-710
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• 2014

An Image-Based Target Tracker maintains LOS(Line Of Sight) to a target by controlling azimuth and elevation gimbals of an ISS(Inertially Stabilized System). Its controller produces the gimbals commands of the ISS using tracking errors provided by an image tracker. The control performance of the target tracker with PI controller generally used for tracking controller is limited because of bandwidth limitation by time delay yielded by image capture and processing of the image tracker. In this paper, tracking controller using target states estimator is proposed which can enhance the tracking performance under the highly dynamic maneuvering conditions of the ISS and the target. Simulation results show that the proposed method can improve the tracking performance than that with only PI controller.

• IEMEK Journal of Embedded Systems and Applications
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• v.13 no.6
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• pp.321-328
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• 2018

This paper presents an automatic target tracking flight system using a PID controller based on velocity command of a multirotor UAV. The automatic flight system includes marker based onboard target detection and an automatic velocity command generation replacing manual controller. A quad-rotor UAV is equipped with a camera and an image processing computer to detect the marker in real time and to estimate the relative distance from the target. The marker tracking system consists of PID controller and generates velocity command based on the relative distance. The generated velocity command is used as the input of the UAV's original flight controller. The operation of the proposed system was verified through actual flight tests using a marker on top of a moving vehicle and tracks it to successfully demonstrate its capability using a quad-rotor UAV.

• Journal of Institute of Control, Robotics and Systems
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• v.14 no.10
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• pp.1053-1061
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• 2008

In this paper, a moving target tracking using a binocular vision for an omni-directional mobile robot is addressed. In the binocular vision, three dimensional information on the target is extracted by vision processes including calibration, image correspondence, and 3D reconstruction. The robot controller is constituted with SPI(serial peripheral interface) to communicate effectively between robot master controller and wheel controllers.

• Journal of the Korea Institute of Military Science and Technology
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• v.20 no.3
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• pp.352-361
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• 2017

This paper proposes a design and fabrication of the test equipment that is implemented as a part of the airborne tracking radar inspection under the environment of indoor simulation. This test equipment provides controlling the operation status of airborne tracking radar and replicating the velocity and range information of target by generating a variety of target signal. This is mainly composed of radar operation controller, target signal generator, horn antenna driving devices. Radar operation controller is able to perform the controlling of radar operation mode and monitoring in real time by serial communication. Target signal generator is generated doppler signal and range delayed signal using virtual target of RF-band. Horn antenna driving devices perform a role of target simulating exercise. In the end, the performance is demonstrated using experiment results of test equipment for airborne tracking radar.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.40 no.2
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• pp.118-128
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• 2012

The goal of this paper is to design the target tracking controller for a quadrotor micro UAV using a vision sensor. First of all, the mathematical model of the quadrotor was estimated through the Prediction Error Method(PEM) using experimental input/output flight data, and then the estimated model was validated via the comparison with new experimental flight data. Next, the target tracking controller was designed using LQR(Linear Quadratic Regulator) method based on the estimated model. The relative distance between an object and the quadrotor was obtained by a vision sensor, and the altitude was obtained by a ultra sonic sensor. Finally, the performance of the designed target tracking controller was evaluated through flight tests.

• Proceedings of the KIEE Conference
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• 1995.11a
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• pp.583-586
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• 1995

In this paper, a nor fuzzy control algorithm for the target tracking system is proposed, and its characteristics are analyzed and compared with those of the traditional PID controller. Fuzzy rules are generated experimentally using Mamdani's minimum operation and the center of area method. The experimental results prove that the proposed fuzzy algorithm is excellent in our tracking system and its performance is superior to that of the PID controller.

• Journal of Institute of Control, Robotics and Systems
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• v.10 no.6
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• pp.510-518
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• 2004

The PID trajectory tracking controller for robotic systems shows performance limitation imposed by inverse dynamics according to desired trajectory. Since the equilibrium point can not be defined for the control system involving performance limitation, we define newly the quasi-equilibrium region as an alternative for equilibrium point. This analysis result of performance limitation can guide us the auto-tuning method for PID controller. Also, the quasi-equilibrium region is used as the target performance of auto-tuning PID trajectory tracking controller. The auto-tuning law is derived from the direct adaptive control scheme, based on the extended disturbance input-to-state stability and the characteristics of performance limitation. Finally, experimental results show that the target performance can be achieved by the proposed automatic tuning method.

• International Journal of Control, Automation, and Systems
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• v.1 no.1
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• pp.83-92
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• 2003

The outdoor antenna servo system is subject to has significant torque disturbances from wind pressures and gusts on the antenna structures, as well as bearing and aerodynamic frictions. This control system should provide a sharp directivity in spite of the environmental disturbances and internal uncertainties. Therefore, the implementation of a real-time controller is necessary for the precise generation of the reference signal and robust tracking performance. In this paper, the discrete-time controller for the quick tracking of a target communication satellite is designed by applying the sampled-data $H_{\infty}$ control theory along with the reference signal generated by an improved conventional step-tracking algorithm. The sampled-data $H_{\infty}$controller demonstrates superior robustness for the longer sampling period when compared with a simple PID controller.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.1 s.94
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• pp.200-209
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• 1999

This paper presents a precise tracking control scheme for the proposed parallel robot using artificial neural network. This control scheme is composed of three feedback controllers and one feedforward controller. Conventional PD controller and artificial neural network are used as feedback and feedforward controller respectively. A backpropagation learning strategy is applied to the training of artificial neural network, and PD controller outputs are used as target outputs. The PD controllers are designed at the robot dynamics based on inter-relationship between active joints and moving platform. Feedback controllers insure the total stability of system, and feedforward controller generates the control signal for trajectory tracking. The precise tracking performance of proposed control scheme is proved by computer simulation.

• Journal of Institute of Control, Robotics and Systems
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• v.19 no.5
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• pp.450-456
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• 2013

This paper suggests the target tracking method improved for the collaboration of the quad rotor type UAV (Unmanned Aerial Vehicle) and omnidirectional Unmanned Ground Vehicle. If UAV shakes or UGV moves rapidly, the existing method generates a phenomenon that the tracking object loses the tracking target. To solve the problems, we propose an algorithm that can track continually when they lose the target. The proposed algorithm stores the vector of the landmark. And if the target was lost, the control signal was inputted so that the landmark could move continuously to the direction running out. Prior to the experiment, Proportional and integral control were used in 4 motors in order to calibrate the Heading value of the omnidirectional mobile robot. The landmark of UGV was recognized as the camera adhered to UAV and the target was traced through the proportional-integral-derivative control. Finally, the performance of the target tracking controller and proposed algorithm was evaluated through the experiment.