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유도전동기 노이즈 저감과 속도 제어를 위해 H-Bridge회로를 통해 L298모터 제어에 관한 연구이다. 일 반적으로 PWM방식은 인버터에 발생된 고조파와 노이즈 그리고 스위칭 주파수, dv/dt와 di/dt 스위칭 방법에 의 해 영향을 받는다. 모터의 속도는 단속되는 전압 펄스폭에 따라서 다르게 되므로 이 펄스의 폭을 ATMEGA128의 타이머 카운터를 이용해 제어한다. ATMEGA128의 L298을 연결하고 그 후단에 유도전동기를 연결한다. 그리고 타이머 카운터 0에서 프로그램으로 버튼을 누르면 버튼 값을 체크하여 switch문을 통해 구분하고 Up버튼이면 0CR 값을 10씩 올리고 Down버튼이면 10씩 내리도록 하면 모터의 스텝각 등의 기본 특성이 다양하게 나타난다. 본 연구에서는 H-Bridge을 이용한 유도전동기의 노이즈 저감을 위한 출력 필터 설계를 목적으로 한다.

This is a study on L298 motor control through H-Bridge circuit for noise reduction and speed control of induction motor. The PWM method is affected by the harmonics and noise generated in the inverter and the switching frequency dv/dt and di/dt switching method. Since the speed of the motor varies according to the intermittent voltage pulse width, the width of this pulse is controlled using the timer counter of ATMEGA128. Connect the L298 of ATMEGA128 and connect the induction motor to the rear end. Then press the button with the program at timer counter 0. At this time, check the button value and increase the 0CR value by 10 if it is the Up button through the switch statement, and decrease it by 10 if it is the Down button. At this time, various basic characteristics such as the step angle of the motor appear. The purpose of this study is to design an output filter for noise reduction of induction motors using H-Bridge.

The adaptive power control of Code Division Multiple Access (CDMA) systems for communications between User Equipments (UEs) with a link-budget based Signal-to-Interference Ratio (SIR) estimate which has distance information is applied to three inner loop power control algorithms. The speed estimation performances of these algorithms with their consecutive Transmit-Power-Control (TPC) ratios are compared to each other, and it is concluded that the speed can be estimated using the TPC ratio information of Consecutive TPC Ratio Step-size Closed Loop Power Control (CS-CLPC) and Fixed Step-size Power Control (FSPC).

There has been increasingly large demand for next generation high speed transport system to compliment air travel and for aerospace vehicle launchers for uses such as low orbit space transports. In this study, characteristics of two pulsed power accelerator designs commonly referred as Rail Gun and Gauss Gun were tested with the custom designed experimental set up. Velocity and various side effects during the operation of the accelerator, such as “suck-back” effect and rail erosion were noted and were used to achieve minimum set of controls defined as controlled acceleration, deceleration and deflection respectively. The experimental system with four sets of acceleration motors were able to achieve acceleration with measured energy efficiency peaking at 3 percent. It was concluded that the concept of transport system utilizing electromagnetic pulsed power system can be viable with relatively simple requirements while allowing unique designs without its form factor limited to conventional strictly linear path.

The purpose of this study was to investigate the effect of recumbent cycling with integrated volitional control electrical stimulation (IVES) on gait ability in stroke patients. Six stroke patients (all male; average age, 55.7±8.3 years) participated. Recumbent cycling (R-cycling) was per-formed with and without IVES in the power assist (IVES-P) mode. The targeted muscle for electrostimulation was the tibialis anterior. Patients performed 10 min of IVES-P mode plus R-cycling (program A) or R-cy-cling alone (program B), once per day, 5 times per week. Patients com-pleted two sets of each program, alternating between programs each week. Gait speed and the number of steps numbers on a 10-m walking test was assessed before and after each interventional session. Pro-gram A improved gait speed, but not the number of steps, to a greater extent than that in program B. Specifically, the combined intervention significantly improved gait speed in the first set, but not the second set of the intervention. R-cycling with IVES-P mode improved gait speed during the recovery stage in stroke patients to a greater extent than that achieved with R-cycling alone. Thus, this combined therapy has poten-tial as a standardized treatment in the field of rehabilitation medicine.

자율주행 시스템의 수용성 보장은 중요하다. 시스템 수용성 요소 중 하나인 자율주행 종방 향 제어기는 상위 제어기와 하위 제어기로 구성된다. 상위 제어기는 Cruise 제어와 Space 제어 를 상황에 맞는 제어를 결정하고 필요한 목표 속도를 만든다. 하위 제어기에서는 목표 속도를 추종하기 위한 가속도 신호를 만들어서 제어를 수행한다. 본 논문에서는 상위 제어기에서 Cruise 제어와 Space 제어전환 문제에서 발생하는 차간거리 변동을 개선하는 알고리즘을 제안 한다. 제안한 방법은 Cruise 제어에서 Space 제어로 전환되는 시점에 Cruise 제어에 Approach 알고리즘을 추가하여 전환 거리에서 Space 제어로 전환되도록 하는 것이다. 이를 통해서 ± 12m 초기 오차에서 ±4m까지 오차를 개선했으며 실차검증을 수행하였다.

Driver acceptance of autonomous driving is very important. The autonomous driving longitudinal controller, which is one of the factors affecting acceptability, consists of a high-level controller and a low-level controller. The host controller decides the cruise control and the space control according to the situation and creates the required target speed. The sub-controller performs control by creating an acceleration signal to follow the target speed. In this paper, we propose an algorithm to improve the inter-vehicle distance fluctuations that occur in the cruise control and space control switching problems in the host controller. The proposed method is to add an approach algorithm to the cruise control at the time of switching from cruise control to space control so that it is switched to space control at the correct switching distance. Through this, the error was improved from 12m error to 4m, and actual vehicle verification was performed.

최적 이론은 평가지표에 의해 구성된 비용함수를 최소화하는 자장 좋은 해를 구하는 이론이다. 최적제어 기는 최적 이론을 적용하여 비용함수를 최소로 하는 시스템의 제어 입력을 구하여 상태 피드백 제어기를 구성한 다. 적분기를 갖는 최적제어기를 IP(Integral Proportional) 제어기의 구조와 동일하도록 설계하여 그 구조를 보이 고 시스템 파라미터와 가중치로 제어 이득의 설정할 수 있음을 보인다. 그 결과를 전동기에 적용하여 0.1% 이내 의 정상상태 속도 추종 오차를 가짐을 확인할 수 있다.

Optimal theory is a framework for finding the best solution that minimizes a cost function composed of evaluation metrics. An optimal controller applies this theory to design a state feedback controller that determines the control input minimizing the cost function. The optimal controller with an integrator is designed to match the structure of an IP(Integral Proportional) controller, demonstrating that control gains can be set using system parameters and weights. Applying this result to a motor confirms that the steady-state speed tracking error remains within 0.1%.

In this study, the change in the mold opening stroke of important functional parts according to the 20, 50, 80, and 100% increase in the injection speed of a hydraulic 150 ton hydraulic injection molding machine was studied to verify the accuracy of the injection speed and mold opening stroke and the reproducibility of the standard deviation. The null and alternative hypotheses were confirmed by conducting hypothesis verification according to the experimental condition change using the experimental design method.

The author introduces a test platform system that has been developed for variable-speed controlmoment gyroscopes(VCMGs). VCMGs are important actuators for spacecraft attitude control. The testplatform consists of two VCMGs driven by servo motors and sensor modules. The control program hasbeen coded by the NI LabVIEW. Accelerometers and gyros have been used to measure the attitude angleand angular speed of the platform. The 2nd order low pass filters have effectively filtered out noisesfrom measurements. Wheel speeds and gimbal angles have been controlled satisfactory by PI control. Through some tests, moment generation has been verified. The moment has been generated ascommanded. However, friction effect by a ball bearing, that supports the platform’s rotation, has beennot negligible. As further studies, friction reduction will be studied. In conclusion, this test platform willbe used for engineering education and research.

본 연구는 도시부 첨두시간에 수요 초과로 발생하는 만성 정체와 상류 교차로까지 확산되 는 스필백을 완화하기 위한 상류부 속도제어 전략을 다룬다. 모터스포츠의 세이프티카 개념을 응용하여 상류 링크의 자율주행 선두 군집에 속도 상한을 부여하고, VISSIM 기반으로 자율주 행 시스템 보급률(Market Penetration Rate, MPR) 0%, 25%, 50%, 75% ,100%별로 시나리오를 구 성하여 대기행렬 길이와 SSAM 대리 안전지표로 효과를 평가하였다. 분석 결과 MPR 75% 이 상에서 스필백 위험과 대기행렬이 유의하게 감소하고 대기행렬이 축 방향으로 분산되었다. 다 만 과도한 감속은 안전성 향상 효과를 줄이고 변동성을 키우는 trade-off가 확인되었다. 본 연구 는 자율주행 혼재 단계에서 실시간 속도제어를 통해 완전 자율주행 도입 이전에도 교통관리와 안전성을 향상시킬 수 있음을 기대하며 그 정책적 근거를 제시한다.

This study examines an upstream speed-control strategy to mitigate chronic peak-period congestion and spillback propagation in urban corridors. Inspired by the motorsport Safety-Car concept, an upper speed limit is applied to a leading platoon of automated vehicles on upstream links. Using VISSIM, scenarios were designed for Market Penetration Rates (MPR = 0%, 25%, 50%, 75%, 100%), and their effects were evaluated through queue lengths and surrogate safety measures derived from the Surrogate Safety Assessment Model (SSAM). Results show that, at MPR levels of 75% and higher, spillback risk and queue lengths significantly decrease and queues become more longitudinally dispersed along the corridor. However, excessive deceleration partially offsets safety gains and increases variability, indicating a trade-off between stability and efficiency. The findings suggest that adaptive, real-time speed control in mixed traffic can enhance traffic management and safety even before full automation, providing a practical policy basis for early-stage autonomous driving environments.