• Proceedings of the KIEE Conference
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• 2004.05a
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• pp.33-37
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• 2004

To meet an increasing demand for high performance in gun dynamic plant, both a precise and a fast response positioning are strongly required for the gun servomechanism control. A mode switching control(MSC) system, which includes a fine stabilizing controller, fast positioning one and a switching function, is widely used to meet this requirement. Stabilization is performed through PID controller, while proximate time optimal servo(PTOS) is used for target designation. Because gun dynamic have large damping comparing to acceleration, PTOS algorithm with damping is newly derived. This paper adopts the initial value compensation method that improve the transient response after switching. Some simulation results are given to show the effectiveness of our scheme.

• Transactions of the Korean Society of Automotive Engineers
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• v.21 no.4
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• pp.8-15
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• 2013

Recently many kinds of electric vehicles have been developed as many governments demand the environmental friendly vehicles. In this paper, study of load optimization for the electric vehicle which has multiple axle power system was conducted. For the analysis of the vehicle which has three or four driving axles, a method based on the geometry and assumptions that considering axles as a spring model and normal forces of the axles are proportional to the displacement of the axles was applied with basic vehicle dynamics. With the developed vehicle analysis technique, algorithm to find the optimal motor operating points was developed. Using this algorithm, it was possible to find the optimization of vehicle load distribution for multiple axles according to the driving cycles. Also, control logic for the vehicle can be developed based on the optimization simulation results.

• Advances in Automotive Engineering
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• v.1 no.1
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• pp.105-121
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• 2018

The hybrid electric powertrain is a robust solution that allows for major improvements in both fuel economy and emission reduction. In the present study, a through-the-road hybrid vehicle model with an electric motor driving the rear axle and an Internal Combustion Engine (ICE) driving the front axle has been constructed. We then present a systematic method for the determination of a real time applicable optimal Energy Management Strategy (EMS) for a hybrid road vehicle. More precisely, we compare the performance of rule-based EMS strategies to an optimization-based strategy, namely ECMS (Equivalent Consumption Minimization Strategy). The comparison is conducted in parallel with a parameterization of the size of the internal combustion engine and the implementation of a Continuously Variable Transmission (CVT) that allows following the line of best fuel economy. For the FTP-75 driving cycle, the constrained engine On-off control algorithm is shown to offer a 28% improvement potential of fuel consumption compared to the conventional internal combustion engine while the ECMS strategy achieves an improved potential of nearly 33%.

• Journal of the korean Society of Automotive Engineers
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• v.14 no.5
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• pp.95-106
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• 1992

Active control of acoustic noise is an application area of adaptive digital signal processing with increasingly interest along the last year. This work studies the implementation of the multichannel LMS filter and the application of this algorithm for the reduction of the noise inside a vechicle cabin using a number of 'secondary sources' drived by adaptive filtering of a reference noise source. Firstly, we propose the use of an adaptive method for the time-varient optimal convergence factor. Secondly, we propose the use of adaptive delayed inverse model to estimate the elastic-acoustic transfer function presented in vechicle cabin. The original, primary source is often periodic, with a known fundamental frequency. A suitably filtered reference signal can thus be used to drive the secondary sources. An algorithm is presented for adapting the coefficients of an FIR filter feeding such a secondary source in such a way as to minimize the output of a suitably placed microphone. In this algorithm, the coefficients of adaptive filter driving an array of secondary sources can be adapted to minimize the sum of the squares of the outputs of a number of error microphones. The multichannel LMS algorithm displays that such an algorithm is considered suitable to used for the global suppression of noise in vehicle cabin.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.1624-1627
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• 1997

The 6-DOF parallel manipulator is a closed-kindmatic chain robot manipulator that is capable of providing high structural rigidity and positional accuracy. Because of its advantage, the parallel manipulator have been widely used in many engineering applications such as vehicle/flight driving simulators, rogot maniplators, attachment tool of machining centers, etc. However, the kinematic analysis for the implementation of a real-time controller has some problem because of the lack of an efficient lagorithm for solving its highly nonliner forward kinematic equation, which provides the translational and orientational attitudes of the moveable upper platform from the lenght of manipulator linkages. Generally, Newton-Raphson method has been widely sued to solve the forward kinematic problem but the effectiveness of this methodology depend on how to set initial values. This paper proposes a hybrid method using genetic algorithm(GA) and Newton-Raphson method to solve forward kinematics. That is, the initial values of forward kinematics solution are determined by adopting genetic algorithm which can search grobally optimal solutions. Since determining this values, the determined values are used in Newton-Raphson method for real time calcuation.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.26 no.1
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• pp.88-100
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• 1990

Since sea state changes engine load instantaneously, the speed governing apparatus is essential for marine engine to maintain constant speed regardless of the load. As governing apparatuses, mechanical, pneumatic, and electric governors have been employed. But, recently, according to the introduction of low speed-ling stroke engines to increase thermal efficiency, the development of governor which has better response characteristics is requisite. In this paper, to design the governor that meets above requirement, author made a performance test for the existing PID control digital governor with the aid of computer simulation, and investigated digital governor applying the optimal control algorithm, then, executed computer simulation by the same way. As the result of simulations, found that the former let engine have large overshoot and long settling time at low speed, on the other hand, the latter made engine have better response. If we design and invent a good observer for delay time element so that the optimal control theory can be applied, better governor will be expected.

• The Transactions of the Korean Institute of Power Electronics
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• v.13 no.6
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• pp.420-429
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• 2008

This paper describes design procedure and control strategy of HDC(High side DC/DC Converter) and MCU(Motor Control Unit) for diesel hybrid electric vehicle. In designing HDC and MCU for HEV high power density and reliability is strongly needed to meet the demand of automotive industry. In order to achieve the high performance of a controller, MPC5554 based control board is developed. An optimized film capacitor and inductor are also developed for high efficiency driving. Skim 63 IGBT module of SEMIKRON for automotive is used for power switching device. The most efficient cooling model for optimal size and reliability were verified by simulation. These procedures are verified by bench or driving test and the results are present in this paper.

• Journal of Auto-vehicle Safety Association
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• v.15 no.4
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• pp.16-22
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• 2023

This paper presents a proactive longitudinal motion planning algorithm for improving the safety of an automated bus. Since the field of view (FOV) of the autonomous vehicle was limited depending on onboard sensors' performance and surrounding environments, it was necessary to implement vehicle-to-vehicle (V2V) communication for overcoming the limitation. After a virtual V2V-equipped target was constructed considering information obtained from V2V communication, the reference motion of the ego vehicle was determined by considering the state of both the V2V-equipped target and the sensor-detected target. Model predictive control (MPC) was implemented to calculate the optimal motion considering the reference motion and the chance constraint, which was deduced from manual driving data. The improvement in driving safety was confirmed through vehicle tests along actual urban roads.

• Journal of the Korean Society of Industry Convergence
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• v.17 no.3
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• pp.151-169
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• 2014

We propose a new technique for autonomous navigation and travelling of mobile robot based on ultrasonic sensors through the narrow labyrinth that leave only distance of a few centimeters on each side between the guides and the robot. In our current implementation the ultrasonic sensor system fires at a rate of 100 ms, that is, each of the 8 sensors fires once during each 100 ms interval. This is a very good firing rate, implemented here for optimal performance. This paper presents an extensively tested and verified solution to the problem of obstacle avoidance. Our solution is based on the optimal placement of ultrasonic sensors at strategic locations around the robot. Both the sensor location and the associated navigation algorithm are defined in such a way that only the accurate radial sonar data is used for accurate travelling.

• Journal of the Institute of Electronics and Information Engineers
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• v.54 no.6
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• pp.123-133
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• 2017

In this paper, we developed an optimal flicker-free control algorithm operating within 16 luminance implementation bits and 512 brightness implementation pulses irrespective of LPM(LED Pixel Matrix) module configuration on dynamic driving method of LED display system. As an implementation method, we turned the refresh rate up by increasing the number of scans through multiple shift-latches which were devised from conventional shift-latch scheme for full color representation. As a result, the LED display system of this method has no flicker phenomenon because of the novel refresh rate higher than 2,040[Hz] incomparable to 240~480[Hz] of conventional system.