Jeong-Ju Jeong

This paper presents a new direct active and reactive power control (DPC) scheme for a three-phase gridconnected voltage source inverter (VSI) based on the passivity viewpoint using the port-controlled Hamiltonian(PCH) system. The proposed controller consists of feedforward and feedback parts. The feedforward part (the referenceinputs) is generated through the flatness of the dynamics of the VSI model, which makes the error dynamicsin the form of PCH system. The nonlinear feedback part is designe

We propose a new approach for virtual lane prediction. The main contribution of the proposed method is that the predicted virtual lane can be substituted for lane detection using a camera sensor when the camera image processing fails to detect the lane. The proposed method generates the predicted virtual lane using the relative movement between a vehicle and a lane. To predict the lane, a third-order polynomial function of the longitudinal distance is used as a lane model. Each coefficient of th

In this paper, we propose the use of fault-tolerant techniques for an autonomous lane keeping system (LKS) under sensor failure of the camera vision sensor. When the output of the vision sensor is not available to the LKS due to malfunction and/or environmental conditions, it is necessary for the lateral control system to maintain its stability before the driver takes over control authority. We propose a method for fault-tolerant control using the lateral kinematic vehicle motion model. The kine

This paper presents a nonlinear feedback controller for a permanent-magnet synchronous generator(PMSG) wind turbine system based on port-controlled Hamiltonian system. For the simplification, this work focuseson the nonlinear control law of the grid side converter (GSC) that is directly connected to the grid and affectedduring network disturbances. The proposed controller is designed through the analysis of PMSG GSC model fromthe passivity viewpoint in order to regulate the reference of the DC v

A fault detection method with parity equations is proposed in this paper. Due to its low cost implementation, the velocity of the motor is not measurable in electric parking brake (EPB) systems. Therefore, residuals are not reliable when estimating the motor velocity with a low-resolution encoder. In this paper, we propose a fault detection method with sensorless estimation using current ripples that estimates the position and velocity of the motor by detecting periodical oscillations of the arm

Monitoring of the cutting force signals in a cutting process has been well emphasized in machine tool communities. Although the cutting force can be directly measured by a tool dynamometer, this method is not always feasible because of high cost and limitations in setup. In the paper an indirect cutting force monitoring system is developed so that the cutting force in a turning process is estimated based on an AC spindle drive model. This monitoring system considers the cutting force as a distur

In this study, we present an estimator of vertical tire forces based on Unscented Kalman Filter(UKF) to improve the performance of the chassis control. When the vehicle is maneuvered to change lanes, the vertical load transfer caused by the centrifugal force can affect cornering stability and rollover. In the previous study, a Kalman Filter with a fixed gain, obtained from infinite horizon, has been conventionally used. However, this estimator does not fully compensate for the model’s uncertaint

In this paper, we develop a sliding mode controller that uses a nonlinear sliding manifold for the permanent magnet synchronous motor. The proposed controller makes sure that both currents and velocity tracking error converge into equilibria. Nonlinear sliding manifold consists of current dynamics and nonlinear functions which are designed with velocity tracking error and its integrated term. The nonlinear functions are designed to guarantee that velocity tracking error converge into zero. The c

It is known that HIV (Human Immunodeficiency Virus) infection, which causes AIDS after some latent period, is a dynamic process that can be modeled mathematically. Effects of available anti-viral drugs, which prevent HIV from infecting healthy cells, can also be included in the model. In this paper we illustrate control theory can be applied to a model of HIV infection. In particular, the drug dose is regarded as control input and the goal is to excite an immune response so that the symptom of i

This paper presents a robust controller using a Linear Parameter Varying (LPV) model of a lane-keeping system with parameter reduction. Both varying vehicle speed and roll motion on a curved road influence the lateral vehicle model’s parameters, such as tire cornering stiffness. Thus, we use the LPV technique to take the parameter variations into account in vehicle dynamics. However, multiple varying parameters lead to a high number of scheduling variables and cause massive computational complex

In this paper, we propose a fault tolerant method for lane recognition in a vision-based lane keeping system (LKS). In the presence of vision sensor failure due to malfunction and/or environmental conditions, LKS immediately releases its control. For vehicle safety, it is required to provide available virtual lane information to LKS until the driver becomes aware of the situation and takes over control of the steering system. Thus, we cope with vision system failure by proposing a new lane estim

In this paper, we propose cascade-form velocity controller for a permanent magnet synchronous motor (PMSM). The proposed controller consists of a sliding-mode controller (SMC) for the inner current control loop and a model-predictive controller (MPC) for the outer velocity control loop. With SMC, we can ensure that the current tracking error always converges to zero in finite time. The SMC is designed to track the desired currents. Additionally, with MPC, we can obtain the optimal velocity contr

This paper presents an advanced °attening method to precisely analyze nanostructures by using atomic force microscopy. Distortions caused by the slope of a sample and nonlinearities of the Z scanner can a®ect the height of the scanned image and make the scanned image di±cult to use for quantitative analysis. We propose an advanced °attening method to °atten an image that does not require the user to be experienced. The distortions can be measured and systematically removed from a scanned image.

We propose a multi-rate sensor fusion of vision and radar using Kalman filter to solve problems ofasynchronized and multi-rate sampling periods in object vehicle tracking. A model based prediction of object vehicles isperformed with a decentralized multi-rate Kalman filter for each sensor (vision and radar sensors.) To obtain theimprovement in the performance of position prediction, different weighting is applied to each sensor’s predicted objectposition from the multi-rate Kalman filter. The pr

Assigning the correspondences among moving objects, which are measured from two different sensors such as radar and vision, is difficult when the ego vehicle is changing its lane. In this paper, we propose a robust and reliable decision method of the correspondences between radar and vision when the ego vehicle is changing its lane. A particle filter that consider the yaw rate of the ego vehicle and a convex hull method are proposed to improve the object ID association. In addition, the overall