Publications

IdPublisherVenueTitleSummaryCategoriesAuthorYearLinkPDF
98Society for the Advancement of Material and Process EngineeringA Machine Learning-based Portable Inspection Method For Evaluation Of Tool Surface Condition And Release Coating In Composites Manufacturing

Composites Manufacturing, Tooling Inspection, Machine …

Conference paperC. Schoenholz, S. Li, K. Bainbridge, V. Huynh, A. Gray, X. Chen, and N. Zobeiry2022

https://www.researchgate.net/publication/360973644_A_machine_learning-based_portable_inspection_method_for_evaluation_of_tool_surface_condition_and_release_coating_in_composites_manufacturing

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97Advanced Intelligent Mechatronics Understanding and Controlling the Sensitivity of Event Cameras in Responding to Static Objects

Reflectivity, Sensitivity, Mechatronics, …

Conference paperQ. Gao* , X. Sun* , Z. Yu, and X. Chen2023

https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10196152

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96American Control ConferenceLeast Squares Solution for System Identification with Non-uniform Data under a Coprime Collaborative Sensing Scheme

Closed-form solutions, Collaboration, Control systems, System …

Conference paperJinhua Ouyang, Xu Chen2023

https://ieeexplore.ieee.org/document/10156141

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95American Control ConferenceTarget Tracking Under Delayed and Irregularly-Sampled Visual Feedback for a Robotic Air-Hockey System

Target tracking, Atmospheric modeling, Robot vision …

Conference paperHui Xiao and Xu Chen2022

https://ieeexplore.ieee.org/document/9867354

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94ASME Letters Dyn. Sys. ControlMulti-Track Melt Pool Width Modeling in Powder Bed Fusion Additive Manufacturing

modeling, control implementation, powder bed fusion, additive manufacturing, control applications, dynamics and control, …

Journal paperDan Wang, Xu Chen2023DOWNLOAD
93ASME Letters Dyn. Sys. ControlA Recursive System Identification With Non-Uniform Temporal Feedback Under Coprime Collaborative Sensing

recursive system identification, collaborative sensing, identifiability, least-squares method, model reparameterization, fast input slow …

Journal paperJinhua Ouyang, Xu Chen2023DOWNLOAD
92Journal of Materials Research and Technology 26 (2023)Microstructure and Microhardness of Electron Beam Melted Ti-6Al-4V Components with Differential Thickness in Initial Deposition Layers

Additive manufacturing, Electron beam melting, Powder bed fusion, Ti-6Al-4V, Microstructure, …

Journal paperM. S. Bin Abdullah, E. Bol, G. Kelley, C. Doyle, R. Schleusener, M. Mojib, X. Chen, D. Arola, and M. Ramulu.2023

https://www.sciencedirect.com/science/article/pii/S2238785423021348?via%3Dihub

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91Introduction to Modern Controls – with Illustrations in MATLAB and Python

You will learn how to use state- space methods to make, study, and control dynamic systems. You will explore topics like state-space models and solutions, stability, controllability, observability, state-feedback control, optimal control, observers, observer state feedback controls, least square estimation, Kalman filter, and Linear Quadratic Gaussian optimal …

BookXu Chen and Masayoshi Tomizuka2023

https://faculty.washington.edu/chx/project/intro-modern-control-book/

90Materials Today CommunicationsA review of aging, degradation, and reusability of PA12 powders in selective laser sintering additive manufacturing

This paper reviews the state-of-the-art on important aspects of aging mechanisms and degradation behaviors of polyamide 12 powders in …

Journal paperFeifei Yang, Navid Zobeiry, Ramulu Mamidala, Xu Chen2022

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892022 IFAC Mechatronics & MOVIC symposiumA robotic chess player and the impacts of mechanical and environmental setting in data collection

Robotic chess player, mechanical and environmental …

AbstractColin Acton; Xiaohai Hu; Mingyu Wang; Xu Chen2022

to appear

to appear

88IEEE/ASME Transactions on MechatronicsAdaptive Lighting for Curved and Nonuniform Objects in Optomechanical Inspection Systems

We discuss the mathematical problem formulation, analytic solution, optimality of the proposed lighting, and experimental results in imaging curved …

Journal paperMark Gerges; Xu Chen2022

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to appear

87IEEE/ASME Transactions on MechatronicsPreheating Temperature Control and Low-Contrast Imaging Data Analytics for Laser Powder Bed Fusion

We propose a model-based multizone heating control for minimizing the powder bed temperature deviation and an image analytics framework for process …

Journal paperTianyu Jiang; Mengying Leng; Xu Chen2022

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86ISFA 2022 | International Symposium on Flexible AutomationA Mass-Transfer Based Approach to Model and Predict Volatile Organic Compound Emission from Selective Laser Sintering

This work proposes a mass-transfer and experiment-data based approach to model and predict VOC emission in …

Conference paperFeifei Yang; Xu Chen2022

to appear

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852021 Annual International Solid Freeform Fabrication SymposiumA Control of Surface Quality in Selective Laser Sintering Additive Manufacturing with Reclaimed Polyamide Materials

Aiming to improve the surface quality, we propose a novel approach for SLS with (extremely) aged polyamide 12 …

Conference paperFeifei Yang; Tianyu Jiang; Xu Chen; Greg Lalier; John Bartolone2021

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842021 IEEE/ASME International Conference on Advanced Intelligent Mechatronics (AIM)Control-oriented Mechatronic Design and Data Analytics for Quality-assured Laser Powder Bed Fusion Additive Manufacturing

This paper presents the design of a full-scale, fully accessible polymer laser powder bed fusion testbed with tailored mechatronic designs for in-situ monitoring and …

Conference paperTianyu Jiang; Mengying Leng; Xu Chen2021

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83ASTM International Selected Technical PapersControl-oriented In-situ Imaging and Data Analytics for Coaxial Monitoring of Powder Bed Fusion Additive Manufacturing

The objective of this study is to discuss a data processing infrastructure for coaxial sensing towards consistent and repetitive additive …

Conference paperTianyu Jiang; Mengying Leng; Xu Chen2021

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82Journal of Manufacturing ProcessesA combined theoretical and experimental approach to model polyamide 12 degradation in selective laser sintering additive manufacturing

In this work, we propose a first-instance kinetic model considering the effects of both oxygen and laser to model the material degradation in polyamide 12 …

Journal paperFeifei Yang; Xu Chen2021

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81The International Journal of Advanced Manufacturing TechnologyQuantitative influences of successive reuse on thermal decomposition, molecular evolution, and elemental composition of polyamide 12 residues in selective laser sintering

This work experiments successive reuse of polyamide 12 residues and quantitatively monitors the thermal decomposition, molecular evolution, and compositional changes of the material in SLS …

Journal paperFeifei Yang; Angela Schnuerch; Xu Chen2021

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80Polymer Degradation and StabilityEvaluating poly (ether ether ketone) powder recyclability for selective laser sintering applications

This work evaluates the changes that occur in thermally treated PEEK powder through spectroscopic, morphological, and rheological …

Journal paperAkanksha Patel; Varun Venoor; Feifei Yang; Xu Chen; Margaret J. Sobkowicz2021

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79ASME Letters in Dynamic Systems and ControlNew Hammerstein Modeling and Analysis for Controlling Melt Pool Width in Powder Bed Fusion Additive Manufacturing

This paper first builds a finite element model (FEM) of the thermal fields to look into the convoluted thermal interactions during the PBF …

Journal paperDan Wang; Xinyu Zhao; Xu Chen2021

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78ASTM International Conference on Additive Manufacturing (ASTM ICAM 2020)A new kinetic modelling of polyamide 12 degradation in selective laser sintering

By a combined theoretical and experimental mapping of the actual material degradation rates into the oxidation physics, we obtain the coefficients of the actual coupled oxygen and laser effects in …

Conference paperFeifei Yang, Xu Chen2021

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77International Journal of Intelligent Robotics and ApplicationsRobotic Target Following with Slow and Delayed Visual Feedback

This paper presents a visual servoing algorithm for target following under slow and delayed feedback. It’s an extended version of my DSCC 2019 …

Journal paperHui Xiao, Xu Chen2020

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76Polymer TestingProcess control of surface quality and part microstructure in selective laser sintering involving highly degraded polyamide 12 materials

To improve the surface quality and to build interrelations between process parameters and surface quality, we propose a novel approach for SLS with (extremely) aged polyamide 12 …

Journal paperFeifei Yang; Tianyu Jiang; Greg Lalier; John Bartolone; Xu Chen2020

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75Journal of Dynamic Systems, Measurement and ControlClosed-loop High-fidelity Simulation Integrating Finite Element Modeling with Feedback Controls in Additive Manufacturing

This paper builds a first-instance closed-loop simulation framework by integrating high-fidelity finite element modeling with feedback controls originally developed for general mechatronics …

Journal paperDan Wang; Xu Chen2020

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74Journal of Manufacturing ProcessesA process control and interlayer heating approach to reuse polyamide 12 powders and create parts with improved mechanical properties in selective laser sintering

This work proposes a new process control method to maximize reusability of aged and extremely aged polyamide 12 …

Journal paperFeifei Yang; Tianyu Jiang; Greg Lalier; John Bartolone; Xu Chen2020

DOI

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73Dynamic Systems and Control Conference (DSCC) 2020New Hammerstein Modeling and Analysis for Controlling Melt Pool Width in Powder Bed Fusion Additive Manufacturing

This paper first builds a finite element model (FEM) of the thermal fields to look into the convoluted thermal interactions during the PBF …

Conference paperDan Wang; Xinyu Zhao; Xu Chen2020

to appear

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722020 International Symposium on Flexible AutomationActive interlayer heating for sustainable selective laser sintering with reclaimed polyamide 12 powders

Selective laser sintering; powder reuse; powder aging and degradation; interlayer heating; …

Conference paperFeifei Yang; Tianyu Jiang; Xu Chen; Greg Lalier; John Bartolone2020

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71IEEE/CAA Journal of Automatica SinicaH-infinity-based Selective Inversion of Nonminimum-phase Systems for Feedback Controls

this paper provides a new treatment of unstable zeros in inverse design. We provide first an intuitive pole-zero-map-based inverse tuning to verify the basic principle of the unstable-zero …

Journal paperDan Wang; Xu Chen2020

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702020 International Symposium on Flexible Automation Closed-loop Simulation Integrating Finite Element Modeling with Feedback Controls in Powder Bed Fusion Additive Manufacturing

This paper builds a first-instance closed-loop simulation framework by utilizing the output signals retrieved from the finite element model …

Conference paperDan Wang; Xu Chen2020

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69Renewable EnergyMultivariable Robust Blade Pitch Control Design to Reject Periodic Loads on Wind Turbines

wind turbine; vibration rejection; energy …

Journal paperYuan Yuan; Xu Chen; Jiong Tang2020

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68ASME Letters in Dynamic Systems and ControlControl-oriented Modeling and Repetitive Control in In-layer and Cross-layer Thermal Interactions in Selective Laser Sintering

builds a modeling and control framework of the key thermodynamic interactions between the laser source and the materials to be …

Journal paperDan Wang; Tianyu Jiang; Xu Chen2020

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67IEEE Transactions on Industrial ElectronicsA Collaborative Sensing and Model-Based Real-Time Recovery of Fast Data Flows From Sparse Measurements

multirate signal processing; information recovery; disturbance beyond Nyquist …

Journal paperHui Xiao; Yaakov bar-shalom; Xu Chen2019

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66ASME Dynamic Systems and Control ConferenceFollowing Fast-Dynamic Targets With Only Slow And Delayed Visual Feedback—A Kalman Filter and Model-Based Prediction Approach

We propose a new framework with Kalman filters and multirate model-based prediction (1) to reconstruct fast-sampled 3D target position and velocity data, and (2) to compensate the time delay for general robotic motion …

Conference paperHui Xiao; Xu Chen2019

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65IEEE Transactions on Control Systems TechnologyLocal Loop Shaping for Rejecting Band-Limited Disturbances in Nonminimum-Phase Systems With Application to Laser Beam Steering for Additive Manufacturing

local loop shaping; energy modulation; disturbance observer; inverse-free control; selective laser sintering; additive …

Journal paperTianyu Jiang; Hui Xiao; Jiong Tang; Liting Sun; Xu Chen2019

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64ASME Dynamic Systems and Control ConferenceWide-band Loop Shaping for Modulation of Energy Transmission in Nonminimum-phase Systems

introduces a loop-shaping approach to create such wideband closed-loop behaviors, with a particular focus on systems with nonminimum-phase …

Conference paperTianyu Jiang; Jiong Tang; Xu Chen2018

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63American Control ConferenceA multirate repetitive control for fractional-order servos in laser-based additive manufacturing

studies repetitive control (RC) algorithms to advance the quality of repetitive energy deposition in laser-based additive manufacturing …

Conference paperDan Wang; Xu Chen2018

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62International Symposium on Flexible Automation Synthesis and Analysis of Multirate Repetitive Control for Fractional-order Periodic Disturbance Rejection in Powder Bed Fusion (Best Paper Award)

studies control approaches to advance the quality of repetitive energy deposition in powder bed fusion (PBF) additive …

Conference paperDan Wang; Xu Chen2018

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61ASME Dynamic Systems and Control ConferenceModel-based Sparse Information Recovery by Collaborative Sensor Management

considers the real-time recovery of a fast time series (e.g., updated every T seconds) by using sparsely sampled measurements from two sensors whose sampling intervals are much larger than T (e.g., MT and NT, where M and N are …

Conference paperHui Xiao; Yaakov Bar-Shalom; Xu Chen2018

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60SPIE Smart Structures and Materials + Nondestructive Evaluation and Health MonitoringPeriodic wind disturbance rejection using robust individual pitch control

a robust individual pitch control strategy is presented to deal with periodic load disturbances on wind turbines under operating point …

Conference paperYuan Yuan; Xu Chen; Jiong Tang2018

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59Mechanical Systems and Signal ProcessingDiscrete-time nonlinear damping backstepping control with observers for rejection of low and high frequency disturbances

disturbance observer; augmented observer; discrete time control; …

Journal paperWonhee Kim; Xu Chen; Youngwoo Lee; Chung Choo Chung; Masayoshi Tomizuka2018

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58MechatronicsRejecting Fast Narrow-band Disturbances with Slow Sensor Feedback for Quality Beam Steering in Selective Laser Sintering

disturbance rejection; nyquist frequency; control algorithm; selective laser …

Journal paperHui Xiao; Tianyu Jiang; Xu Chen2018

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57IEEE Transactions on Control Systems TechnologyTransmission of Signal Nonsmoothness and Transient Improvement in Add-on Servo Control

transient control; discontinuity; impulsive …

Journal paperTianyu Jiang; Xu Chen2018

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56IEEE Transactions on MechatronicsA Spectral Analysis of Feedback Regulation Near and Beyond Nyquist Frequency

feedback regulation; high-gain control; Nyquist frequency; sampled-data …

Journal paperDan Wang; Xu Chen2018

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55Control Engineering PracticeA multirate fractional-order repetitive control for laser-based additive manufacturing

selective laser sintering; laser scanning mechanism; numerical simulation; multirate sampled-data …

Journal paperDan Wang; Xu Chen2018

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54Annual Inter- national Solid Freeform Fabrication SymposiumRealtime Control-Oriented Modeling and Disturbance Parameterization for Smart and Reliable Powder Bed Fusion Additive Manufacturing

develop and validatea surrogate modeling of in-process disturbances induced by the periodic in- and cross-layerthermomechanical …

Conference paperXu Chen; Dan Wang; Tianyu Jiang; Hui Xiao2018

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53United States Patent Data storage devices and methods with frequency-shaped sliding mode control (US patent 9542966)

the servo controller is configured to generate an adjusted position error signal based on a position error signal and an estimated microactuator position …

PatentMinghui Zheng; Xu Chen; Masayoshi Tomizuka; Wei Xi; Guoxiao Guo2017

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52ASME Information Storage and Processing Systems ConferenceControl of Dual-Stage HDDs With Enhanced Repetitive Disturbance Rejection

the dual-stage HDD is introduced to enhance the HDD control performance for extended bandwidth and improved disturbance …

Conference paperShiying Zhou; Minghui Zheng; Xu Chen; Masayoshi Tomizuka2017

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51ASME Dynamic Systems and Control ConferenceAn Inverse-Free Disturbance Observer For Adaptive Narrow-Band Disturbance Rejection With Application To Selective Laser Sintering (Best Vibration Paper Award, ASME DSCD)

a Youla-Kucera parameterization based forward-model selective disturbance observer (FMSDOB) is proposed for flexible servo control with application to …

Conference paperTianyu Jiang; Hui Xiao; Xu Chen2017

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50IEEE International Conference on Advanced Intelligent MechatronicsMulti-band beyond-Nyquist Disturbance Rejection on a Galvanometer Scanner System

introduces a multi-rate control scheme to fully reject narrow-band beyond-Nyquist disturbances in galvanometer scanner …

Conference paperHui Xiao; Xu Chen2017

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49Advances in Mechanical EngineeringA tutorial on loop-shaping control methodologies for precision positioning systems

precision control; feedback design; Youla–Kucera parameterization; disturbance rejection; loop shaping; galvo …

Journal paperDan Wang; Xu Chen2017

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48IEEE Transactions on MagneticsAdaptive Loop Shaping for Wide-Band Disturbances Attenuation in Precision Information Storage Systems

adaptive control; disturbance …

Journal paperLiting Sun; Tianyu Jiang; Xu Chen2017

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47International Journal of Adaptive Control and Signal ProcessingA Robust Optimal Design for Strictly Positive Realness in Recursive Parameter Adaptation

strictly positive real; adaptive control; system …

Journal paperHui Xiao; Loan D; Landau; Xu Chen2017

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46ASME Journal of Dynamic Systems, Measurement, and ControlDisturbance Observer-Based Pitch Control of Wind Turbines for Enhanced Speed Regulation

wind turbine; vibration rejection; energy …

Journal paperYuan Yuan; Xu Chen; Jiong Tang2017

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45ASME Dynamic Systems and Control ConferenceDisturbance Observer Based Control Design for Wind Turbine Speed Regulation

an internal model-based disturbance observer (DOB) design combined with a PID type feedback controller is formulated for wind turbine speed and power …

Conference paperYuan Yuan, Xu Chen, Jiong Tang2016

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44International Symposium on Flexible AutomationSpectral Distribution and Implications of Feedback Regulation beyond Nyquist Frequency

a fundamental challenge in digital and sampled-data control arises when the continuous-time plant is subject to fast disturbances that possess significant frequency components beyond Nyquist …

Conference paperDan Wang; Masayoshi Tomizuka; Xu Chen2016

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43SPIE Smart Structures and Material Systems + Nondestructive Evaluation and Health MonitoringDisturbance Observer Based Pitch Control of Wind Turbines for Disturbance Rejection

a disturbance observer based (DOB) control scheme is illustrated to reject the unknown low frequency disturbances to wind …

Conference paperYuan Yuan; Xu Chen; Jiong Tang2016

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42Mediterranean Conference on Control and AutomationInterlaced Direct Adaptive Regulation Scheme Applied to a Benchmark Problem

an adaptive regulation scheme using the Internal Model Principle and an IIR Youla-Kučera controller parametrization is proposed for the suppression of multiple unknown and time varying narrow band …

Conference paperIoan Doré Landau; Abraham Castellanos Silva; Luc Dugard; Xu Chen2016

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41American Control ConferenceExtended State Observer with Phase Compensation to Deal with High-frequency Vibrations in Hard Disk Drives

proposes a phase compensator to recover the inherent phase loss in the traditional …

Conference paperMinghui Zheng; Xu Chen; Masayoshi Tomizuka2016

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40American Control ConferenceEnhanced Wide-Spectrum Vibration Suppression Based on Adaptive Loop Shaping

a direct adaptive control approach is proposed based on adaptive loop shaping and disturbance observer …

Conference paperLiting Sun; Xu Chen; Masayoshi Tomizuka2016

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39American Control ConferenceInput-to-output Discontinuity and Transient Improvement in Add-on Control Design

presents an exact formula for computing the output discontinuity during add-on servo, and discusses its influence on transient performance in different control …

Conference paperTianyu Jiang; Paul Hanrahan; Xu Chen2016

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38American Control ConferenceMultirate Forward-model Disturbance Observer for Feedback Regulation beyond Nyquist Frequency

provides a discrete-time regulation scheme for exact sampled-data rejection of disturbances beyond Nyquist …

Conference paperXu Chen; Hui Xiao2016

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37IEEE Transactions on Control Systems TechnologyDiscrete-time Reduced-Complexity Youla Parameterization for Dual-input Single-output Systems

precision control; loop shaping; vibration rejection; discrete-time Youla parameterization; dual-stage actuation; dual-stage hard disk drives; multi-input single-output …

Journal paperXu Chen; Masayoshi Tomizuka2016

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36Systems & Control LettersMultirate Forward-model Disturbance Observer for Feedback Regulation beyond Nyquist Frequency

disturbance beyond Nyquist frequency; disturbance rejection; disturbance …

Journal paperXu Chen; Hui Xiao2016

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35European Journal of ControlModified direct adaptive regulation scheme applied to a benchmark problem

Adaptive regulation; Active vibration control; Inertial actuators; Multiple narrow band disturbances; Youla–Kučera parametrization; Internal Model …

Journal paperAbraham Castellanos Silva; Ioan Doré Landau; Luc Dugard; Xu Chen2016

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34United States Patent Data storage device comprising slew rate anti-windup compensation for microactuator (US patent US9007714)

an input signal to a compensator is generated, wherein the compensator is configured to generate a microactuator control …

PatentMinghui Zheng; Xu Chen; Haiming Wang; Young-Hoon Kim; Wei Xi; Kuang-Yang Tu2015

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33International Conference on Complex Systems EngineeringAn Open-source Selective Laser Sintering Additive Manufacturing System

International Conference on Complex Systems …

PosterTianyu Jiang; Xu Chen2015
32American Control ConferenceReal-time kinematic modeling and prediction of human joint motion in a networked rehabilitation system

a networked-based rehabilitation system is introduced for lower-extremity …

Conference paperWenlong Zhang; Xu Chen; Joonbum Bae; Masayoshi Tomizuka2015

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31American Control ConferenceDiscrete-time output feedback nonlinear control for combined low- and high-frequency disturbance compensation

present a discrete-time output feedback nonlinear control algorithm for reference tracking under both broad-band disturbances at low frequencies and narrow-band disturbances at high …

Conference paperWonhee Kim; Xu Chen; Chung Choo Chung; Masayoshi Tomizuka2015

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30AutomaticaPseudo Youla-Kucera parameterization with control of the waterbed effect for local loop shaping

control of waterbed; local loop shaping; all-stabilizing …

Journal paperXu Chen; Tianyu Jiang; Masayoshi Tomizuka2015

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29International Journal of Adaptive Control and Signal ProcessingOverview and new results in disturbance observer based adaptive vibration rejection with application to advanced manufacturing

disturbance observer; narrow-band loop shaping; manufacturing …

Journal paperXu Chen Masayoshi Tomizuka2015

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28United States Patent Disk drive filtering disturbance signal and error signal for adaptive feed-forward compensation (US patent US8922938)

a disturbance signal is generated in response to a vibration, and the disturbance signal is filtered with a first filter comprising a frequency response to generate a filtered disturbance …

PatentXu Chen; JianGuo Zhou; Wei Xi; Kuang-Yang Tu; Guoxiao Guo2014

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27United States Patent Methods for Closed-loop Compensation of Ultra-high Frequency Disturbances in Hard Disk Drives and Hard Disk Drives Utilizing Same (US patent US863005)

a disturbance observer (DOB) uses the control command and the plant output to generate a delayed and estimated version of the disturbance. The DOB comprises a Q filter having a selected center …

PatentXu Chen; Wei Xi; Young-hoon Kim; Kuang-Yang Tu2014

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26ASME Dynamic Systems and Control ConferenceAdaptive suppression of high-frequency wide-spectrum vibrations with application to disk drive systems

presents an adaptive algorithm to identify and suppress these high-frequency wide-spectrum …

Conference paperLiting Sun; Xu Chen; Masayoshi Tomizuka2014

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25ASME Dynamic Systems and Control ConferenceAdaptive sliding mode spacecraft attitude control

an adaptive sliding mode spacecraft attitude controller, has the advantage of not requiring knowledge of the inertia of the spacecraft, and rejecting unexpected external disturbances, with global asymptotic position and velocity …

Conference paperYizhou Wang; Xu Chen; Masayoshi Tomizuka2014

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24World Congress of the International Federation of Automatic ControlTransient enhancement in add-on feedforward algorithms for high-performance mechatronic systems

analyze the problem of control injection in feedforward compensation, and discuss the transient enhancement in add-on feedforward …

Conference paperXu Chen; Masayoshi Tomizuka2014

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23World Congress of the International Federation of Automatic ControlDiscrete-time frequency-shaped sliding mode control for audio-vibration rejection in hard disk drives

a discrete-time frequency-shaped sliding mode control (FSSMC) is proposed for audio-vibration rejection in Hard Disk Drives …

Conference paperMinghui Zheng; Xu Chen; Masayoshi Tomizuk2014

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22ISCIE/ASME International Symposium on Flexible AutomationSelective iterative learning control to deal with iteration-dependent disturbances (Best Paper Finalist)

discuss a new ILC strat-egy with a disturbance observer (DOB) and a time-varying Qfilter for improved …

Conference paperLiting Sun; Xu Chen; Masayoshi Tomizuka2014

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21ASME Annual Conference on Information Storage & Processing SystemsA nonlinear feedback control scheme for transient performance enhancement in hard disk drives

aims to develop a nonlinear control algorithm to break the limitations of linear PID controls and improve the transient performance during the short-span track seeking / settling in hard disk drives …

Conference paperMinghui Zheng; Xu Chen; Masayoshi Tomizuka2014

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20IEEE Transactions on Control Systems TechnologyNew repetitive control with improved steady-state performance and accelerated transient

repetitive control; control of waterbed; manufacturing …

Journal paperXu Chen ; Masayoshi Tomizuka2014

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19ASME Journal of Dynamic Systems, Measurement, and ControlOptimal decoupled disturbance observers for dual-input single-output Systems

disturbance observer; dual-stage precision …

Journal paperXu Chen , Masayoshi Tomizuka2014

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18ASME Dynamic Systems and Control ConferenceControl design for cancellation of unnatural reaction torque and vibrations in variable-gear-ratio steering system

proposes a control method to cancel this unnatural torque. We address the problem by using a tire sensor and a set of feedback and feedforward …

Conference paperAtsushi Oshima; Xu Chen; Sumio Sugita; Masayoshi Tomizuka2013

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17IEEE/ASME International Conference on Advanced Intelligent MechatronicsReduced-complexity and robust youla parameterization for discrete-time dual-input-single-output systems

explore special forms of Youla parameterization for obtaining stabilizing controllers for DISO systems, and discuss concepts to achieve reduced-complexity formulations with clearer design …

Conference paperXu Chen; Masayoshi Tomizuka2013

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16European Control ConferenceSelective Model Inversion and Adaptive Disturbance Observer for Rejection of Time-varying Vibrations on an Active Suspension

an idea of selective model inversion (SMI) for a (possibly nonminimum phase) plant dynamics at multiple narrow frequency regions, so that vibrations can be estimated and canceled by …

Conference paperXu Chen; Masayoshi Tomizuka2013

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15American Control ConferenceControl methodologies for precision positioning systems (Tutorial Paper)

considers the control aspect for precision positioning. In motion control systems at nano/micro levels, it has been noted that the control algorithm should be customized as much as possible to the spectrum of …

Conference paperXu Chen; Masayoshi Tomizuka2013

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14ASME Information Storage and Processing Systems ConferenceNeural-network based automatic pid gain tuning in the presence of time-varying disturbances in hard disk drives

presents automatic online gain tuning of PID controllers based on neural …

Conference paperLiting Sun; Xu Chen; Masayoshi Tomizuka2013

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13IFAC Symposium on Mechatronic SystemsInverse-based local loop shaping and IIR-filter design for precision motion control

discuss a feedback loop-shaping approach to address such a class of control …

Conference paperXu Chen; Atsushi Oshima; Masayoshi Tomizuka2013

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12American Society for Precision Engineering Spring Topical Meeting and the MIT Laboratory for Manufacturing and Productivity Annual SummitAdd-on loop shaping via youla parameterization for precision motion control

discuss add-on loop-shapingideas via Youla parameterization, aka all stabilizing controller parameterization, for improvedservo …

Conference paperXu Chen; Masayoshi Tomizuka2013

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11European Journal of ControlSelective model inversion and adaptive disturbance observer for time-varying vibration rejection on an active-suspension benchmark

narrow-band loop shaping; adaptive …

Journal paperXu Chen; Masayoshi Tomizuka2013

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10ASME Dynamic Systems and Control Conference | Motion & Vibration ConferenceDecoupled disturbance observers for dual-input-single-output systems with application to vibration rejection in dual-stage hard disk drives (Best Paper in Session Award)

presents a new extension of the DOB idea to dual-input-single-output systems, and discusses an optimal Q-filter …

Conference paperXu Chen; Masayoshi Tomizuka2012

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09ASME Dynamic Systems and Control Conference | Motion & Vibration ConferenceA convex optimization approach for solving the robust strictly positive real (spr) problem

proposes a convex optimization approach to address the robust SPR …

Conference paperXu Chen; Masayoshi Tomizuka2012

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08ASME/JSME Joint International Conference on Micromechatronics for Information and Precision EquipmentReduced-complexity adaptive youla parameterization for broadband-vibration rejection in dual-stage hard disk drives

ASME/JSME Joint International Conference on Micromechatronics for Information and Precision …

Conference paperXu Chen; Masayoshi Tomizuka2012
07IEEE/ASME International Conference on Advanced Intelligent MechatronicsAn enhanced repetitive control algorithm using the structure of disturbance observer

presents a new structural configuration of the internal model principle in repetitive control, wherein designers have more flexibility in the repetitive loop-shaping design, and amplification of non-repetitive errors can be greatly …

Conference paperXu Chen; Masayoshi Tomizuka2012

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06IEEE Transactions on Control Systems TechnologyA minimum parameter adaptive approach for rejecting multiple narrow-band disturbances with application to hard disk drives

narrow-band loop shaping; adaptive control; …

Journal paperXu Chen; Masayoshi Tomizuka2012

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05World Congress of the International Federation of Automatic ControlSpiral servo writing in hard disk drives using iterative learning based tracking control

discusses high precision tracking control algorithms for the writing of spiral servo …

Conference paperXu Chen; Masayoshi Tomizuka2011

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04ASME Annual Conference on Information Storage & Processing Systems A structure for all stabilizing controllers and its applications to narrow-band disturbance rejection in hard disk drives

ASME Annual Conference on Information Storage & Processing …

Conference paperXu Chen; Masayoshi Tomizuka2011
03IFAC Symposium on Mechatronic SystemsAn indirect adaptive approach to reject multiple narrow-band disturbances in hard disk drives

presents an indirect adaptive control scheme that rejects unknown multiple narrow-band disturbances in hard disk drive …

Conference paperXu Chen; Masayoshi Tomizuka2010

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02ASME Dynamic Systems and Control ConferenceUnknown multiple narrow-band disturbance rejection in hard disk drives-an adaptive notch filter and perfect disturbance observer approach

an adaptive control scheme is developed to reject unknown multiple narrow-band disturbances in a hard disk …

Conference paperXu Chen; Masayoshi Tomizuka2010

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01American Control ConferenceOptimal plant shaping for high bandwidth disturbance rejection in discrete disturbance observers

robustness of the DOB is improved by shaping the true plant with a cascaded frequency shaping filter, while the nominal plant model remains …

Conference paperXu Chen; Masayoshi Tomizuka2010

DOI

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