bluuebunny/crossref_metadata_2025 huggingface dataset:
Integrated System Identification and Control Design for an IC Engine Variable Valve Timing System
Authors: Ren Zhen , Zhu Guoming G.
Published: February 2011

This paper applies integrated system modeling and control design process to a continuously variable valve timing (VVT) actuator system that has different control input and cam position feedback sample rates. Due to high cam shaft torque disturbance and high actuator open-loop gain, it is fairly difficult to maintain the cam phase at the desired constant level with an open-loop controller. As a result, multirate closed-loop system identification is a necessity. For this study, multirate closed-loop system identification, PRBS q-Markov Cover, was used for obtaining linearized system models at different engine operational conditions; and the output covariance constraint (OCC) controller, an H2 controller, was designed based upon the identified model and evaluated on the VVT test bench. Performances of the designed OCC controller was compared with those of the baseline PI controller on the test bench. Results show that the OCC controller uses less control effort and has less overshoot than those of PI ones.
Compensating the Distributed Effect of a Wave PDE in the Actuation or Sensing Path of Multi-Input and Multi-Output LTI Systems
Authors: Bekiaris-Liberis Nikolaos , Krstic Miroslav
Published: February 2011

The problem of compensation of infinite-dimensional actuator or sensor dynamics of more complex type than pure delay was solved recently using the backstepping method for PDEs. In this paper we construct an explicit feedback law for a multi-input LTI system which compensates the wave PDE dynamics and stabilizes the overall system. Our design is based on a novel infinite-dimensional backstepping-forwarding transformation. We illustrate the effectiveness of our design with a simulation example of a single-input second order system, in which the wave input enters the system through two different channels, each one located at a different point in the domain of the wave PDE. Finally, we consider a dual problem where we design an exponentially convergent observer that compensates the distributed effect of the wave sensor dynamics.
A Control Oriented SI and HCCI Hybrid Combustion Model for Internal Combustion Engines
Authors: Yang Xiaojian , Zhu Guoming G. , Sun Zongxuan
Published: February 2011

The combustion mode transition between SI (spark ignited) and HCCI (Homogeneously Charged Compression Ignition) of an IC (Internal Combustion) engine is challenge due to the thermo inertia of residue gas; and model-based control becomes a necessity. This paper presents a control oriented two-zone model to describe the hybrid combustion that starts with SI combustion and ends with HCCI combustion. The gas respiration dynamics were modeled using mean-value approach and the combustion process was modeled using crank resolved method. The developed model was validated in an HIL (Hardware-In-the-Loop) simulation environment for both steady-state and transient operations in SI, HCCI, and SI-HCCI hybrid combustion modes through the exhaust valve timing control (recompression). Furthermore, cooled external EGR (exhaust gas re-circulation) was used to suppress engine knock and enhance the fuel efficiency. The simulation results also illustrates that the transient control parameters of hybrid combustion is quite different from these in steady state operation, indicating the need of a control oriented SI-HCCI hybrid combustion model for transient combustion control.
Development and Experimental Validation of a Control-Oriented Diesel Engine Fuel Consumption and Brake Torque Predictive Model for Hybrid Powertrain Control Applications
Authors: Chiara Fabio , Wang Junmin , Patil Chinmaya B. , Hsieh Ming-Feng , Yan Fengjun
Published: February 2011

This paper describes the development and experimental validation of a control-oriented, real-time-capable, Diesel engine instantaneous fuel consumption and brake torque model under warmed-up conditions. Such a model, with the capability of reliably and computationally-efficiently estimating the aforementioned variables at steady-state and transient engine operating conditions, can be utilized in the context of real-time control and optimization of hybrid powertrains. The only two inputs of the model are the torque request and the engine speed. While Diesel engine dynamics are highly nonlinear and very complex, by considering the Diesel engine and its control system (engine control unit (ECU)) together as an entity, it becomes possible to predict the engine instantaneous fuel consumption and torque based on only the two inputs. A synergy between different modeling methodologies including physically-based grey-box and data-driven black-box approaches were integrated in the Diesel engine model. The fueling and torque predictions have been validated by means of FTP72 test cycle experimental data from a medium-duty Diesel engine at steady-state and transient operations.
In-Wheel Motor Fault Diagnosis for Electric Ground Vehicles
Authors: Wang Rongrong , Wang Junmin
Published: February 2011

This paper presents an in-wheel motor fault diagnosis method for fault-tolerant control of four-wheel independently driven (4WID) electric vehicles. 4WID electric vehicle is one of the promising architectures for electric ground vehicles. While such a vehicle architecture greatly increases the flexibility for vehicle control, it also raises the requirements on system reliability, safety, and fault tolerance due to the increased number of actuators. A fault diagnosis approach for finding the faulty in-wheel motor/motor driver pair is developed. The proposed diagnosis approach does not need a precise knowledge on tire-road friction coefficient (TRFC). Robustness analysis shows that the approach can work well in the presence of tire modeling errors. Simulations using a high-fidelity, CarSim, full-vehicle model indicated the effectiveness of the proposed in-wheel motor/motor driver fault diagnosis approach.
Optimization of Time-Series Data Partitioning for Parameter Identification
Authors: Sarkar Soumik , Mukherjee Kushal , Jin Xin , Ray Asok
Published: February 2011

This paper presents a data-driven method of parameter identification in nonlinear systems based on the theories of symbolic dynamics. Although construction of finite-state-machine models from symbol sequences has been widely reported, similar efforts have not been expended to investigate partitioning of time series data to optimally generate symbol sequences. A data-set partitioning procedure is proposed to extract features from time series data by optimizing a multi-objective cost functional. Performance of the optimal partitioning procedure is compared with those of other traditional partitioning (e.g., uniform and maximum entropy) schemes. Then, tools of pattern classification are applied to identify the ranges of multiple parameters of a well-known chaotic nonlinear dynamical system, namely the Duffing Equation, from its time series response.
Wavelet-Based Feature Extraction for Behavior Recognition in Mobile Robots
Authors: Jin Xin , Mukherjee Kushal , Gupta Shalabh , Ray Asok
Published: February 2011

This paper introduces a dynamic data-driven method for behavior recognition in mobile robots. The core concept of the paper is built upon the principle of symbolic dynamic filtering (SDF) that is used to extract relevant information in complex dynamical systems. The objective here is to identify the robot behavior from time-series data of piezoelectric sensor signals from the pressure sensitive floor in a laboratory environment. A symbolic feature extraction method is presented by partitioning of two-dimensional wavelet images of sensor time-series data. The K-nearest neighbors (k-NN) algorithm is used to identify the patterns extracted by SDF. The proposed method is validated by experimentation on a networked robotics test bed to detect and identify the type and motion profile of mobile robots.
Predicting Blood Glucose Levels Around Meals for Patients With Type I Diabetes
Authors: Cameron Fraser , Niemeyer Gu¨nter
Published: February 2011

Insulin pumps and continuous glucose monitors enable automatic control of blood glucose (BG) levels for patients with type 1 diabetes. Such controllers should carefully assess the likely future BG levels before injecting insulin, since the effects of insulin are prolonged, potentially deadly, and irreversible. Meals pose a strong challenge to this assessment as they create large, fast disturbances. Fortunately, meals have consistent and predictable effects, if their size and start time are known. We present a predictive algorithm that embeds meal detection and estimation into BG prediction. It uses a multiple hypothesis fault detector to identify meal occurrences, and linear Kalman filters to estimate meal sizes. It extrapolates and combines the state and state covariance estimates to form a prediction of BG values and uncertainties. These inputs enable controllers to assess and trade off the acute risks of low and chronic risks of high BG levels. We evaluate the predictor on simulated and clinical data.
The Impact of Retroactivity on the Input/Output Static Characteristics of a Signaling Component
Authors: Ventura A. C. , Jiang P. , Ninfa A. J. , Van Wassenhove L. , Merajver S. D. , Del Vecchio D.
Published: February 2011

In prior work, we have shown that just as in many engineering systems, impedance-like effects appear at the interconnection of biomolecular systems. These effects are called retroactivity, to extend the notion of impedance to biological systems. Signaling components, such as covalent modification cycles, play a central role in the transmission of signals within a cell and from outside the cell. They are typically found in highly interconnected architectures in which a component has several downstream clients. In this paper, we show that retroactivity from downstream targets decreases the sensitivity of response to an input stimulus.
Quantitative Characterization of Steady-State Ankle Impedance With Muscle Activation
Authors: Lee Hyunglae , Ho Patrick , Rastgaar Mohammad A. , Krebs Hermano Igo , Hogan Neville
Published: February 2011

Characterization of multi-variable ankle mechanical impedance is crucial to understanding how the ankle supports lower-extremity function during interaction with the environment. This paper reports quantification of steady-state ankle impedance when muscles were active. Vector field approximation of repetitive measurements of the torque-angle relation in two degrees of freedom (inversion/eversion and dorsiflexion/plantarflexion) enabled assessment of spring-like and non-spring-like components. Experimental results of eight human subjects showed direction-dependent ankle impedance with greater magnitude than when muscles were relaxed. In addition, vector field analysis demonstrated a non-spring-like behavior when muscles were active, although this phenomenon was subtle in the unimpaired young subjects we studied.
A Two Step Optimization Based Iterative Learning Control Algorithm
Authors: Volckaert Marnix , Swevers Jan , Diehl Moritz
Published: February 2011

This article introduces a general formulation of model based iterative learning control (ILC). The formulation is valid for both linear and nonlinear systems. It is a two step approach, such that after each repetition of the task two (non)linear least squares problems have to be solved. In the first step an optimal model correction is calculated. This is a nonparametric correction to the model in order to describe the measured output signal more accurately. This model correction is used in the second step, which is a model inversion problem. Conventional linear ILC is shown to be a particular case of this general formulation.
A Monopropellant-Powered Muscle Actuation System
Authors: Shen Xiangrong , Christ Daniel
Published: February 2011

This paper describes the design and control of a new monopropellant-powered muscle actuation system for robotic systems, especially the mobile systems inspired by biological principles. Based on the pneumatic artificial muscle, this system features a high power density, as well as characteristics similar to biological muscles. By introducing the monopropellant as the energy storage media, this system utilizes the high energy density of liquid fuel and provides a high-pressure gas supply with a simple structure in a compact form. This addresses the limitations of pneumatic supplies on mobile devices and thus is expected to facilitate the future application of artificial muscles on bio-robotic systems. In this paper, design of the monopropellant-powered muscle actuation system is presented as well as a robust controller design that provides effective control for this highly nonlinear system. To demonstrate the proposed muscle actuation system, an experimental prototype was constructed on which the proposed control algorithm provides good tracking performance.
Active Knee Prosthesis Control With Electromyography
Authors: Wu Sai-Kit , Waycaster Garrett , Shen Xiangrong
Published: February 2011

This paper describes a new electromyography (EMG) based control approach for powered above-knee prostheses. In the proposed control approach, the EMG signals are utilized as the direct control commands to the prosthesis, and thus enable the volitional control by the wearer, not only for locomotive functions, but for arbitrary motion as well. To better integrate the AK prosthesis into the rest of the human body, the control approach incorporates a human motor control mechanism-inspired ‘active-reactive’ model, which combines an active control component that reflects the wearer’s motion intention, with a reactive control component that implements the controllable impedance critical to the safe and stable interaction with the environment. The effectiveness of the proposed control approach was demonstrated through the experimental results for arbitrary free swing and level walking.
Adaptive Control of Multi-Agent Systems for Finding Peaks of Unknown Fields
Authors: Jadaliha Mahdi , Lee Joonho , Choi Jongeun
Published: February 2011

In this paper, we consider a deterministic adaptive control framework to design and analyze a class of multi-agent systems that locate peaks of unknown static fields in a distributed and scalable manner. Each agent is driven by swarming and gradient ascent efforts based on its own recursively estimated field via locally collected measurements by itself and its neighboring agents. The convergence properties of the proposed multi-agent systems are analyzed. We also provide a sampling scheme to facilitate the convergence. The simulation study confirms the convergence analysis of the proposed algorithms.
Role of Automated Symbolic Generation of Plant Models in Control Education
Authors: Tripathi Sumit , Shah Hrishi , Lee Leng-Feng , Krovi Venkat
Published: February 2011

A critical precursor to deployment of model-based controllers for articulated-mechanical-systems is availability of a systematic means for generating plant-model-equations. However, the complexity and tractability of generating and analyzing models serves to limit the size of the chosen examples. Hence, we examine the use of contemporary symbolic-computation tools to assist with the automated symbolic equation generation and subsequent analysis to support control systems course work. In particular, we seek to establish linkage between traditional-approach and block-diagram-based symbolic-modeling and controller-development. The Furuta Pendulum example allows us to showcase the emergence of model-complexity, even in relatively-simple two-jointed mechanical system, while studying various aspects of model-creation, model-linearization and model-based controller development in a timely manner.
Approximating a MIMO, 1D Diffusion System to a Low Order, State-Space Form in Order to Facilitate Controller Design
Authors: Schor Alisha R. , Asada H. Harry
Published: February 2011

Chemical distribution is an important factor in many biological systems, driving the phenomenon known as chemotaxis. In order to properly study the effects of various chemical inputs to an in vitro biological assay, it is necessary to have strict control over the spatial distribution of these chemicals. This distribution is typically governed by diffusion, which by nature is a distributed parameter system (DPS), dependent on both space and time. Much study and literature within the controls community has been devoted to DPS, whose dynamics are marked by partial differential equations or delays. They span an infinite-dimensional state-space, and the mathematical complexity associated with this leads to the development of controllers that are often highly abstract in nature. In this paper, we present a method of approximating these systems and expressing them in a manner that makes a DPS amenable to control using a very low order model. In particular, we express the PDE for one-dimensional chemical diffusion as a two-input, two-output state-space system and show that standard controllers can manipulate the outputs of interest, using pole placement and integral control via an augmented state model.
Towards Electronic Stability Control for Two-Wheeled Vehicles: A Preliminary Study
Authors: De Filippi Pierpaolo , Tanelli Mara , Savaresi Sergio M. , Corno Matteo
Published: February 2011

This paper presents a preliminary study on active stability control systems for motorcycles. The design of such a control system is a fully open problem, and it constitutes quite a challenging task due to the complexity of two-wheeled vehicles dynamics. To address this problem, this paper presents a thorough analysis of the input and output variables which may be considered for stability control and proposes a preliminary controller architecture. The closed-loop performance are tested on a multi-body motorcycle simulator and the results favorably witness the potential safety increase enabled by the controller.
Source Seeking for Nonholonomic Unicycle With Speed Regulation
Authors: Ghods Nima , Krstic Miroslav
Published: February 2011

The simplest strategy for extremum seeking-based source localization, for sources with unknown spatial distributions and nonholonomic unicycle vehicles without position measurement, employs a constant positive forward speed. Steering of the vehicle in the plane is performed using only the variation of the angular velocity. While keeping the forward speed constant is a reasonable strategy motivated by implementation with aerial vehicles, it leads to complexities in the asymptotic behavior of the vehicle, since the vehicle cannot settle—at best it can converge to a small-size attractor around the source. In this paper we regulate the forward velocity, with the intent of bringing the vehicle to a stop, or as close to a stop as possible. The vehicle speed is controlled using simple derivative-like feedback of the sensor measurement (the derivative is approximated with a washout filter) to which a speed bias parameter Vc is added. The angular velocity is tuned using standard extremum seeking. We prove two results. For Vc in a certain range around zero, we show that the vehicle converges to a ring around the source and on average the limit of the vehicle’s heading is either directly away or towards the source. For other values of Vc > 0, the vehicle converges to a ring around the source and it revolves around the source. Interestingly, the average heading of this revolution around the source is more outward than inward—this is possible because the vehicle’s speed is not constant, it is lower during the outward steering intervals and higher during the inward steering intervals. The theoretical results are illustrated with simulations.
Responsible Eigenvalue Approach for Stability Analysis and Control Design of a Single-Delay Large-Scale System With Random Coupling Strengths
Authors: Qiao Wei , Sipahi Rifat
Published: February 2011

A class of linear time-invariant (LTI) consensus system with multiple agents and communication delays among the agents is studied. The delay margin of this MIMO system, that is, the largest amount of the delay that the system can withstand without loosing stability, can be studied by the authors’ Responsible Eigenvalue (RE) concept. RE is able to compress the considered stability problem into the stability problem of a single agent system, from which RE captures the delay margin of the entire MIMO system. RE is used here to design controllers for the MIMO system for the objective of increasing the delay margin. Case studies demonstrate connections between coupling strengths, graph Laplacian, the delay margin of a large-scale consensus system, and control synthesis.
Nonlinear Fault Detection and Isolation for a Lithium-Ion Battery Management System
Authors: Marcicki Jim , Onori Simona , Rizzoni Giorgio
Published: February 2011

Lithium-ion batteries are a growing source for electric power, but must be maintained within acceptable operating conditions to ensure efficiency and reliability. Therefore, a robust fault detection and isolation scheme is required that is sensitive enough to determine when sensor or actuator faults present a threat to the health of the battery. A scheme suitable for a hybrid electric vehicle battery application is presented in this work. The diagnostic problem is formulated as a nonlinear parity equation approach, but is modified for the considered application. Sliding mode observers are designed for input estimation, while the output voltage estimation is performed using an open loop model. The selection of optimal thresholds given a maximum allowable probability of error is also considered. An assessment of the design using real-world driving-cycle data leads to the conclusion that the estimation error of the observers determines a lower bound on the minimum detectable fault magnitude.
LPV-Based Air-Fuel Ratio Control of Spark Ignition Engines Using Two Gain Scheduling Parameters
Authors: Postma Marius J. , Nagamune Ryozo
Published: February 2011

The three way catalytic converter (TWC) is a critical component for the mitigation of tailpipe emissions of modern internal combustion (IC) engines. Because the TWC operates effectively only when the air-fuel ratio is very close to stoichiometric, accurate control of the air-fuel ratio is required. The dynamics of the IC engine can be modeled as a first order plus dead time for controller design purposes and vary with both engine speed and air flow. Traditional control schemes using time-invariant controllers have been successful in guaranteeing stability over the operating range of the engine but have introduced a degree of conservatism. To reduce the conservatism, a gain scheduling controller taking both engine speed and air flow as scheduling parameters is proposed. A linear parameter varying model of the plant is constructed and the controller design method is formulated in terms of linear matrix inequalities yielding a convex optimization problem. The resulting closed-loop system has guaranteed stability and performance over the designed operating range of the engine. Simulations are performed to validate and compare the controller with a time-invariant controller as well as a gain scheduling controller that takes only engine speed as a scheduling parameter.
Header Height Control of a Combine Harvester System
Authors: Xie Yangmin , Alleyne Andrew , Greer Ashley , Deneault Dustin
Published: February 2011

There are appreciable losses in crop output at all the stages in grain production like harvesting, transportation, storage, etc. To reduce grain loss during the harvesting process, it is desirable to effectively control the header height of the combine harvester. The desired header height control is able to follow the shape of the terrain and reject disturbances from the ground. This paper presents an optimal state feedback LQR controller to achieve the control objectives. By properly defining the states and choosing the cost function, the full state feedback controller is shown to accomplish the control goals. Then a reduced states feedback controller, which uses a skyhook damper in the controller, is used to simplify the full state feedback controller. Simulation results show that with less feedback information, the reduced order state feedback controller preserves the ability to achieve good reference tracking and disturbance rejection.
Dynamic Modeling of a Bi-Driven High Speed Ball Screw System
Authors: Wang Jinsong , Liu Yan , Zhao Tong , Ye Peiqing
Published: February 2011

The traditional lumped modeling method in 2 degree of freedoms of a bi-driven high-speed ball screw system can not accurately characterize the high frequency mechanical resonance, which usually limits the dynamic performance of the system. This paper proposes a hybrid parameter modeling method for the bi-driven system. The workbench is modeled with lumped method in 3 degree of freedoms considering the physical dimension of the workbench and the installation location of the ball-nut and slider. The ball screw is modeled with a novel distributed parameter approach with the boundary conditions of the thrust bearings and coupling to describe its elastic characteristics. The ball screw model is integrated into the workbench one to construct a hybrid one, which is optimized by simulation on a typical test bed. The optimized model ignores unimportant parameters of the workbench one and reduces the order of the ball screw one. Compared with the experiment, the optimized hybrid model accurately characterizes both the workbench and ball screw resonance frequency of the bi-driven ball screw system.
Semi-Autonomous Avoidance of Moving Hazards for Passenger Vehicles
Authors: Anderson Sterling J. , Peters Steven C. , Pilutti Tom E. , Tseng H. Eric , Iagnemma Karl
Published: February 2011

This paper presents a method for semi-autonomous hazard avoidance in the presence of unknown moving obstacles and unpredictable driver inputs. This method iteratively predicts the motion and anticipated intersection of the host vehicle with both static and dynamic hazards and excludes projected collision states from a traversable corridor. A model predictive controller iteratively replans a stability-optimal trajectory through the navigable region of the environment while a threat assessor and semi-autonomous control law modulate driver and controller inputs to maintain stability, preserve controllability, and ensure safe hazard avoidance. The efficacy of this approach is demonstrated through both simulated and experimental results using a semi-autonomously controlled Jaguar S-Type.
A Pneumatic Artificial Muscle Actuated Above-Knee Prosthesis
Authors: Waycaster Garrett , Wu Sai-Kit , Shen Xiangrong
Published: February 2011

This paper describes the mechanical design and control approach for an above-knee (AK) prosthesis actuated by pneumatic artificial muscle. Pneumatic artificial muscle (PAM) affords great potential in prosthetics, since this type of actuator features a high power density, and similar characteristics to human muscles. However, there is no application of PAM in AK prosthetics in existing literature to the best knowledge of the authors. In this paper, a design of the prosthesis is presented, which provides sufficient actuation torque for the knee joint in energy consuming locomotive functions such as fast walking and stair climbing. The corresponding control approach is also presented, which combines an impedance-based locomotive controller with a lower-level sliding-mode torque control approach. Experiments on the proposed AK prosthesis have also been conducted to demonstrate the ability to mimic normal gait characteristics.
Interactions Between Fish and Robots: An Experimental Study
Authors: Aureli Matteo , Fiorilli Francesca , Porfiri Maurizio
Published: February 2011

In this paper, we present an experimental study of gregarious fish collective behavior in the presence or absence of biomimetic vehicles. This study is aimed at developing a first understanding of fish shoal controllability using robotic exogenous mates. Macroscopic features of the group schooling are identified through laboratory experiments, conducted in a controlled environment. Experimental evidence proves the existence of qualitatively different shoal collective responses to the exogenous mate. We adapt global observables from statistical mechanics to capture the main features of the shoal collective motion, and identify possible distinct states of aggregation. Further, we investigate the effect of the exogenous mate on the shoal by using a diffusion mapping analysis performed on the global observables. The analysis shows that the exogenous mate is able to exert organizing control actions on the schooling behavior that generally result into a higher cohesion for the shoal.
Topological Analysis of Numerosity-Constrained Social Networks
Authors: Abaid Nicole , Porfiri Maurizio
Published: February 2011

In this study, we present a class of directed graphs with bounded degree sequences, which embodies the physical phenomenon of numerosity found in the collective behavior of large animal groups. Behavioral experiments show that an animal’s perception of number is capped by a critical limit, above which an individual perceives a nonspecific “many”. This species-dependent limit plays a pivotal role in the decision making process of large groups, such as fish schools and bird flocks. Here, we consider directed graphs whose edges model information-sharing between individual vertices. We incorporate the numerosity phenomenon as a critical limit on the intake of information by bounding the degree sequence and include the variability of cognitive processes by using a random variable in the network construction. We analytically compute measures of the expected structure of this class of graphs based on cycles, clustering, and sorting among vertices. Theoretical results are verified with numerical simulation.
Pinpointed Muscle Force Control Taking Into Account the Control DOF of Power-Assisting Device
Authors: Ding Ming , Kurita Yuichi , Ueda Jun , Ogasawara Tsukasa
Published: February 2011

The demand for rehabilitation robots is increasing for the upcoming aging society. Power-assisting devices are considered promising for enhancing the mobility of senior citizen and people with disability. Other potential applications are for muscle rehabilitation and sports training. Various power-assisting devices have been developed for supporting the human joint torque in factory. The main focus of our research is to propose a Pinpointed Muscle Force Control (PMFC) method to control the load of selected muscles by using power-assisting device, thus enabling pinpointed motion support, rehabilitation, and training by explicitly specifying the target muscles. In past research, we have made some achievements. However, using the past control method, all joint torque need to be controlled individually. Limited by the current technology, it is difficult to develop such power-assisting device. In this paper, we developed the muscle force control method by taking into account the control DOF of power-assisting device. Using this method, any existing power-assisting device can be used to realize PMFC, even if this device cannot control all joint torque individually. The validity of this advanced PMFC method and the effects from the control DOF are confirmed in simulation and experiments.
Predictive Energy Management for Parallel Hydraulic Hybrid Passenger Vehicle
Authors: Deppen Timothy O. , Alleyne Andrew G. , Stelson Kim A. , Meyer Jonathan J.
Published: February 2011

In this paper, a model predictive control (MPC) approach is presented for solving the energy management problem in a parallel hydraulic hybrid vehicle. The hydraulic hybrid vehicle uses variable displacement pump/motors to transfer energy between the mechanical and hydraulic domains and a high pressure accumulator for energy storage. A model of the parallel hydraulic hybrid powertrain is presented which utilizes the Simscape/Simhydraulics toolboxes of Matlab. These toolboxes allow for a concise description of the relevant powertrain dynamics. The proposed MPC regulates the engine torque and pump/motor displacement in order to track a desired velocity profile while maintaining desired engine conditions. In addition, logic is applied to the MPC to prevent high frequency cycling of the engine. Simulation results demonstrate the capability of the proposed control strategy to track both a desired engine torque and vehicle velocity.
Preview-Based Output Tracking of Nonminimum-Phase Linear Systems via Trajectory Decomposition: Nanomanipulation Example
Authors: Wang Haiming , Kim Kyongsoo , Zou Qingze , Xu Hongbing
Published: February 2011

In this article, a trajectory-decomposition-based approach to output tracking with preview for nonminimum-phase systems is proposed. When there exists a finite (in time) preview of the future desired trajectory, precision output tracking of nonminimum-phase systems can be achieved by using the preview-based stable-inversion technique. The preview-based stable-inversion technique has been successfully implemented in various high-speed positioning applications. The performance of this approach, however, can become sensitive to system dynamics uncertainty. Moreover, the computation involved in the implementation of this approach can be demanding. In the proposed approach, such preview-based inversion related challenges are addressed by integrating the notion of signal decomposition and the iterative learning control technique together. Particularly, a library of desired output elements and their corresponding control input elements is constructed, and the ILC techniques such as the recently-developed model-less inversion-based iterative control (MIIC) are used to obtain the control input elements that achieve precision output tracking of the corresponding desired output elements. Then the previewed future desired trajectory is decomposed as a summation of desired output elements, and the control input is synthesized by using the input elements selected for the corresponding output elements with chosen pre-actuation time. Furthermore, the required pre-actuation time is quantified based on the stable-inversion theory. The proposed approach is illustrated through simulation study of a nanomanipulation application using a nonminimum-phase piezo actuator model.
Robust Stability Design of PI Controllers for a Non-Reheat Steam Generator Unit
Authors: Gogoi Manoj , Emami Tooran , Watkins John M.
Published: February 2011

In this paper a graphical design method is introduced for finding all proportional integral (PI) controllers that stabilize a single area non-reheat steam generation unit for a range of plant parameters. This problem is solved by finding all achievable PI controllers that robustly stabilize the system. Additive uncertainty modeling is used to describe the uncertain perturbed system. A key advantage of this procedure is that it depends only on the frequency response of the system and does not require the plant transfer function coefficients.
Realization of Finishing Cuts Under Changing Machining Conditions by Machining Support Robots
Authors: Osada Tsuginobu , Yano Ken’ichi , Fofana Mustapha S.
Published: February 2011

Finishing processes such as deburring are performed on a wide variety of products in various quantities by workers on a piece-by-piece basis. Accordingly, the accuracy of the product depends on the worker’s skill. The aim of this research is to develop a finish machining support system. The machining is supported by using a haptic device and controlled by a bilateral control system. Here, we propose a control method based on a machining model made up of several components, including tool speed, feed speed of the tool and others, in order to control the robots under conditions in which it is possible to achieve highly accurate machining surfaces. The motion of a slave robot that requires precise control is controlled automatically, and the worker is given the force calculated by this control method. The effectiveness of this system is shown in a machining experiment.
Equidistance Tracking Nonlinear Controller for Under Actuated Autonomous Underwater Vehicles
Authors: Taheri Behzad , Richer Edmond
Published: February 2011

A new method of path planning and tracking while maintaining a constant distance from underwater moving objects has been developed for autonomous underwater vehicles (AUVs). First a kinematics controller that generates the proper trajectories is designed. Then a dynamics sliding mode controller is employed to drive the vehicle on the desired trajectories. The dynamics controller is robust against the parameter uncertainty in the dynamics model of the vehicle. Results of numerical simulations for INFANTE-AUV model show excellent performance for tracking of an object on sinusoidal trajectory.
Individual Pitch Control for Wind Turbine Load Reduction Including Wake Modeling
Authors: Yang Zhongzhou , Li Yaoyu , Seem John E.
Published: February 2011

Individual Pitch Control (IPC) can greatly benefit the load reduction for wind turbine above the rated power. This research investigates advanced IPC schemes with the wake interaction included. The Jensen wake model is applied for composing the rotor wind profile for downstream turbines under wake interaction, and a switched control strategy is thus developed based on the composite wind profile. The wind profile was generated by modifying the TurbSim codes. The state-space models of wind turbine were generated via FAST. Based on such model, individual pitch controllers were designed following the disturbance accommodating control (DAC) framework for regions of different wind speeds. Simulation results showed that the proposed switching DAC can better reject the wake induced asymmetric load than the single DAC, in addition to the rejection of wind shear disturbance, hub-height wind disturbance. The improvement was observed for rotor speed regulation and reduction in steady loads and fatigue loads in 2P of the tower-base yaw moment.
Grasp Effort Evaluation Based on Muscle Activity
Authors: Ikeda Atsutoshi , Kurita Yuichi , Ogasawara Tsukasa
Published: February 2011

This paper proposes an estimation method of product usability based on tendon forces. The aim of this study is estimation of product usability using the tendon force during an object manipulation. Proposed method focuses on the forces of the tendons which are connected to the muscles. First, we explain the estimation method of product usability. The product usability is estimated quantitatively from the tendon forces. The tendon skeletal model of the index finger and the thumb is constructed to calculate the tendon forces. The tendon forces are calculated based on grasping information using a tendon skeletal model. Next, the cylinder pinching simulation using the proposed method is shown. The simulation result is compared with the human experimental result to evaluate the effectiveness of the proposed method. The sensory evaluation of the subjective grasp effort was conducted with five subjects. The calculated score of the simulation reflects the questionnaire survey result by the subjects. As an application, we show the evaluation results of the cell-phone button pushing. The calculated score by the simulation is also compared with the human questionnaire score. These results indicate that the proposed method can be used for the quantitative evaluation of the product usability.
A Modular-Type Three-Axis Vibration Isolation System Using Negative Stiffness
Authors: Hoque Md. Emdadul , Mizuno Takeshi , Ishino Yuji , Takasaki Masaya
Published: February 2011

A vibration isolation system is presented in this paper which is developed by the combination of multiple vibration isolation modules. Each module is fabricated by connecting a positive stiffness suspension in series with a negative stiffness suspension. Each vibration isolation module can be considered as a self-sufficient single-degree-of-freedom vibration isolation system. 3-DOF vibration isolation system can be developed by combining three modules. As the number of motions to be controlled and the number of actuators are equal, there is no redundancy in actuators in such vibration isolation systems. Experimental results are presented to verify the proposed concept of the development of MDOF vibration isolation system using vibration isolation modules.
Constrained Model Predictive Control of a Continuous Annealing Furnace
Authors: Bitschnau L. , Jakubek S. , Kozek M.
Published: February 2011

For the design of constrained model predictive control of a continuous annealing furnace both the modeling of an industrial furnace and the structure of an appropriate constrained predictive control scheme are presented. The model of the furnace comprises a partitioning of the furnace into suitable heating zones, a description of the spatially discretized moving steel strip, and a dynamic formulation of the heaters. The final process model is of linear state space form and utilizes the energy flow to the heaters as inputs, the ambient temperatures as disturbances, and the temperatures of the strip elements and the heaters as states. The model can be easily adapted to varying operation conditions since all important design parameters of the furnace and the strip can be modified on-line. Utilizing measurement data from an industrial furnace for the model validation shows excellent agreement. The constrained predictive control scheme explicitly considers the disturbance, allows for the inclusion of reference values for the inputs, and simultaneously guarantees constraints on the maximum temperature of the heaters. This structure is shown in simulations to reliably obey multiple and contradictory technological restrictions of the process without the need for lengthy parameter optimizations.
Eigenvalue Assignment Control Method for Linear Time-Varying System With Disturbances
Authors: Zou Xiaotian , Yang Qinmin , Cao Chengyu
Published: February 2011

This paper presents a novel Ackermann-like eigenvalue assignment control architecture for a linear time-varying system in the presence of time-varying disturbances. Eigenvalue assignment architectures are presented as a way to achieving feedback stabilization. This method does not require the transformation of the original system into a phase-variable canonical form nor the computation of the PD-eigenvalue of the original system. An example is given to demonstrate the performance of this proposed control method.
Active Vibration Control of Two Coupled Beams Using Descriptor System State Feedback
Authors: Manderla Maximilian , Schlake Jan , Konigorski Ulrich
Published: February 2011

Based on two stiffly-coupled beams a non-standard approach of modelling and control is introduced, which is based on a descriptor representation of the system. A differential-algebraic model of the mechanical system can be derived intuitively, which directly serves for feedback design. The main contribution of this work is the presentation of a suitable parametric control law in terms of the full set of descriptor states. It is based on a classical coupling control and explicitly shows all degrees of freedom for feedback design. Exemplarily, damping assignment for the two-beam system is performed and some numerical and experimental results are provided for validation.
Robust Control Approach on Diesel Engines With Dual-Loop Exhaust Gas Recirculation Systems
Authors: Haber Benjamin , Wang Junmin
Published: February 2011

This paper presents a robust control approach to achieve an independent control authority over the intake manifold conditions of a medium-duty, V8, Diesel engine with the use of a complex air-path system. The intake manifold conditions in question include gas temperature, pressure, and oxygen mass fraction. The purpose of achieving such a high control authority over these intake manifold conditions is to explore the possibilities of extending the operating ranges of advanced combustion modes like low temperature diffusion combustion (LTDC), homogenous charge compression ignition (HCCI), and pre-mixed charge compression ignition (PCCI). Independent control of these air-path variables is made possible by using a dual-loop exhaust gas recirculation (EGR) system with a two-stage, variable geometry turbocharging (VGT) system. A multi-input-multi-output robust air-path controller was designed based on a control-oriented model identified using a high-fidelity GT-Power model of a medium-duty Diesel engine. Simulation results illustrate the effectiveness of the controller over a limited engine operating range.
Analysis and Design of Hardware Architectures and Control Algorithms for an EPAC
Authors: Formentin Simone , Alli Giovanni , Savaresi Sergio M. , Castelli Dezza Francesco
Published: February 2011

EPACs (Electric Pedal Assisted Cycles) represent a very efficient and fashionable mean of non-polluting transport. They are useful for bringing education, for health service and they guarantee the lowest energy cost per distance traveled. In this paper, a power kit has been designed and implemented on a real electric bicycle. In particular, hardware architectures and control algorithms are developed together, taking in account shared needs. An optimal choice of the components and an innovative overboost strategy characterize the provided system. Experimental results and comparison with a benchmark product available in the market demonstrate the efficiency of the whole system.
Simulation Study and Experimental Testing of Foot-Terrain Dynamics in Piezoelectric Micro-Robots
Authors: Ryou Jeong Hoon , Oldham Kenn
Published: February 2011

In micro-scale environment, contact forces such as adhesion and electrostatic forces, which are generally assumed to be negligible in general macro scale devices, affect the motions of MEMS devices significantly. This paper is an initial exploration of how such forces might influence the locomotion of multi-legged micro-robots, by matching the analytical dynamic simulations to the result from experiments on micro devices including a simple micro-cantilever beam and a bulk piezoelectrically-actuated micro-robotic prototype. Results imply that foot-terrain impacts focusing on primary effects related to electrostatic forces, adhesion forces, and an appropriate coefficient of restitution can provide a reasonable model of micro-scale behavior of a robotic foot.
Dynamic Compensation and Rapid Resonance Identification in Ultrasonic-Vibration-Assisted Microforming System Using Magnetostrictive Actuator
Authors: Wang Zhihua , Zou Qingze , Faidley LeAnn , Kim Gap-Yong
Published: February 2011

In this article, a mechatronic system to compensate for the effect of hardware dynamics and achieve rapid resonance identification for an ultrasonic-vibration-assisted microforming system is developed. Recently, micromachining technology, including microforming, microjoining, and micropunching, has attracted great interests due to the need of miniaturized manufacturing system in emerging applications. It has been demonstrated that significant benefits such as reduction of input energy and prolongation of tool life can be gained by introducing ultrasonic vibration into the micromachining process, particularly when the vibration is maintained at the resonant frequency of the vibrating workpiece. However, the fundamental mechanism of ultrasonic vibration effect during the micromachining process has not yet been understood; the electrical actuators currently used to generate the ultrasonic vibration are bulky and not suitable for miniaturization of the micromachining system; and the control of ultrasonic vibration is primitive and far from being optimal. Motivated by these challenges, a microforming platform based on magnetostrictive actuator has been developed recently. Based on this microforming experiment platform, the main contributions of this article are two folds: (1) the use of a novel iterative learning control technique along with a vibration oscillation regulation circuit to compensate for the effect of the magnetostrictive actuator dynamics on the ultrasonic vibration generation, and thereby maintain the same vibration amplitude across a large excitation frequency range, and (2) the use of the Fibonacci search algorithm to achieve rapid online identification of the resonant frequency. Experimental results obtained from the developed magnetostrictive-based microforming platform are presented and discussed to demonstrate the proposed approach.