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ORIGINAL ARTICLE Application of time delay resonator to machine tools Alireza Akbarzadeh Tootoonchi & Mohammad Sadegh Gholami Received: 27 January 2010 / Accepted: 7 February 2011 / Published online: 9 March 2011 # Springer-Verlag London Limited 2011 Abstract Undesirable vibration can negatively affect the performance of machineries. In case of a machine tool, it negatively affects machining accuracy and tool life. Performance may be improved at the design stage by increasing machine stiffness. However, this is difficult to accomplish with existing machines. This paper implements a delay resonator (DR) on model of a typical machine tool to minimize relative vibration between the cutting tool and workpiece during machining process. The DR is a tunable vibration absorber which converts a conventional passive absorber into a marginally stable resonator. This structure absorbs all the vibratory energy at its point of attachment. A strategy called Stability chartsis used not only to resolve the stability question but also to find out gain and time delay of the absorption. Results show that relative motion between cutting tool and workpiece is reduced significantly. Keywords Delay resonator . Machine tool . Cutting tool . Vibration . Stability charts . MATLAB Simulink 1 Introduction Todays machines are required to take smaller foot print, weight less, more durable while having higher accuracy and operation speed. One way to achieve some of these require- ments is by reducing undesirable vibrations. A great deal of engineering efforts is placed to minimize undesirable vibration of machineries. There are many solutions that may be used such as changing electrical and mechanical stiffness. These parameters may be altered at the design stage for new machines that are not built yet. However, making any fundamental changes to existing machines is usually difficult to implement. Therefore, a method to improve the performance of an existing machine, with a given mechanical and electrical stiffness, is highly desirable. Among manufacturing equipment, machine tools and robots usually require higher accuracies. For example, in machining procedure, the cutting forces generated during the cutting process as well as external excitations will create undesirable vibratory motions of various structural components [1] that must be minimized. In particular, the relative motion between the cutting tool and the workpiece creates undulation on the machined surface, and hence, adversely affects the surface accuracy. Furthermore, if the amplitude of the vibration grows significantly, this undulation becomes the source of oscillatory force in the following pass, which again excites the cutting tool more and eventually leads to an unstable situation. This type of vibration is called regenerative mechanismand occurs due to the closed loop nature of machining operations [1]. One of the major concerns in designing a machine tool structure is, therefore, reducing the relative amplitude of vibration between the tool and the workpiece. If a machine tool is extremely rigid or the excitation frequency is below its first resonance frequency, the entire system will undergo a rigid body motion with no relative vibration between the tool and the workpiece. Thus, efforts are made to maximize the stiffness of a machine tool structure during design and construction. However, several functional requirements need to be satisfied within a limited space. The cost involved in building a very rigid system limits the achievable stiffness of the system, especially that of the cutting tool. Therefore, a certain amount of vibration is unavoidable during operation [2]. In the previous studies, optimization of passive vibration absorbers was effectively A. A. Tootoonchi ME Department, Ferdowsi University of Mashhad, Mashhad, Iran e-mail: [email protected] M. S. Gholami (*) M.Sc. Ferdowsi University of Mashhad, Mashhad, Iran e-mail: [email protected] Int J Adv Manuf Technol (2011) 56:879891 DOI 10.1007/s00170-011-3225-6

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  • ORIGINAL ARTICLE

    Application of time delay resonator to machine tools

    Alireza Akbarzadeh Tootoonchi &Mohammad Sadegh Gholami

    Received: 27 January 2010 /Accepted: 7 February 2011 /Published online: 9 March 2011# Springer-Verlag London Limited 2011

    Abstract Undesirable vibration can negatively affect theperformance of machineries. In case of a machine tool, itnegatively affects machining accuracy and tool life.Performance may be improved at the design stage byincreasing machine stiffness. However, this is difficult toaccomplish with existing machines. This paper implementsa delay resonator (DR) on model of a typical machine toolto minimize relative vibration between the cutting tool andworkpiece during machining process. The DR is a tunablevibration absorber which converts a conventional passiveabsorber into a marginally stable resonator. This structureabsorbs all the vibratory energy at its point of attachment. Astrategy called “Stability charts” is used not only to resolvethe stability question but also to find out gain and timedelay of the absorption. Results show that relative motionbetween cutting tool and workpiece is reduced significantly.

    Keywords Delay resonator . Machine tool . Cutting tool .

    Vibration . Stability charts . MATLAB Simulink

    1 Introduction

    Today’s machines are required to take smaller foot print,weight less, more durable while having higher accuracy andoperation speed. One way to achieve some of these require-ments is by reducing undesirable vibrations. A great deal ofengineering efforts is placed to minimize undesirable vibration

    of machineries. There are many solutions that may be usedsuch as changing electrical and mechanical stiffness. Theseparametersmay be altered at the design stage for newmachinesthat are not built yet. However, making any fundamentalchanges to existing machines is usually difficult to implement.Therefore, a method to improve the performance of an existingmachine, with a given mechanical and electrical stiffness, ishighly desirable. Among manufacturing equipment, machinetools and robots usually require higher accuracies. Forexample, in machining procedure, the cutting forces generatedduring the cutting process as well as external excitations willcreate undesirable vibratory motions of various structuralcomponents [1] that must be minimized. In particular, therelative motion between the cutting tool and the workpiececreates undulation on the machined surface, and hence,adversely affects the surface accuracy. Furthermore, if theamplitude of the vibration grows significantly, this undulationbecomes the source of oscillatory force in the following pass,which again excites the cutting tool more and eventuallyleads to an unstable situation. This type of vibration is called“regenerative mechanism” and occurs due to the closed loopnature of machining operations [1]. One of the majorconcerns in designing a machine tool structure is, therefore,reducing the relative amplitude of vibration between the tooland the workpiece. If a machine tool is extremely rigid or theexcitation frequency is below its first resonance frequency,the entire system will undergo a rigid body motion with norelative vibration between the tool and the workpiece. Thus,efforts are made to maximize the stiffness of a machine toolstructure during design and construction. However, severalfunctional requirements need to be satisfied within a limitedspace. The cost involved in building a very rigid systemlimits the achievable stiffness of the system, especially that ofthe cutting tool. Therefore, a certain amount of vibration isunavoidable during operation [2]. In the previous studies,optimization of passive vibration absorbers was effectively

    A. A. TootoonchiME Department, Ferdowsi University of Mashhad,Mashhad, Irane-mail: [email protected]

    M. S. Gholami (*)M.Sc. Ferdowsi University of Mashhad,Mashhad, Irane-mail: [email protected]

    Int J Adv Manuf Technol (2011) 56:879–891DOI 10.1007/s00170-011-3225-6

  • used to remove undesirable oscillations from mechanicalstructures by Y.C. Shin and K.W. Wang [2]. Other commonpassive approach, modification to the tool holder wasconsidered by Rivin and Kang [3], and in other studies,adding a tuned mass vibration absorber was considered byHopkins and Kosker [3]. In more recent studies, activevibration absorber was used by adding damping to a singleaxis of the structure. In this manner, Matsubara, Yamamoto,and Mizumoto used piezoelectric actuators to apply controlmoments to the boring bar. Their system uses time delay tophase shift an accelerometer signal and achieve narrowbandvelocity feedback control [3]. Subsequently, Tewani, Rouch,and Walcott mounted a piezoelectric reaction mass actuator inthe bar itself and created what they termed an active dynamicabsorber [3]. To eliminate undesirable torsional oscillations inrotating mechanical structures, an active vibration absorptiondevice called centrifugal delayed resonator was introduced byHosek et al. [4]. This device was forced to mimic an idealreal-time tunable absorber utilizing a control torque in theform of proportional angular position feedback with variablegain and time delay. In another study, a DR absorber wasimplemented on a flexible beam, and the dynamic features of

    its structure were studied by Olgac and Jalili [5]. In particular,the stability features obtained through analytical and exper-imental studies were compared. Results obtained concur withthe experimental findings better than the earlier dynamicmodels which use the finite difference method and idealclamped-clamped BCs. In other researches, many experimen-tal methods were developed for the optimization of themachine tool structural response. These approaches,however, were mainly dealt with the structural motionof a machine tool itself, not the relative vibrationbetween a cutting tool and a workpiece. Since thecutting tool or workpiece often is the most flexible part

    Concept of DR

    Selecting a representave machine tool

    Modeling

    Identifying state variables

    State-space representation of the system dynamics

    Show advantageous of using DR

    Comparing results

    DR attached to Tool holderDR attached to workpiece

    MATLAB SIMULATION model for 2 case studies

    Select g and Identify stability zoneIdentify time delay and gain

    Stability analysis of the combinedsystem (Machine + DR)

    Select location for DR

    Cutting Tool Workpiece

    Fig. 1 A detailed flow chartdepicting major steps carried outin this paper

    Ma

    Ka Ca

    Ma

    Ka Ca

    a) b)

    Fig. 2 a Passive absorber. b DR absorber with acceleration feedback

    880 Int J Adv Manuf Technol (2011) 56:879–891

  • of an entire machine tool system, optimizing the rigidityof other structural components might have little effects onreducing the relative vibration at the cutting point [6, 7].Robustness of the control strategy against fluctuations in thestructural parameters of the controlled system was addressedby Martin Hosek and Olgac [8]. A new example waspresented by Olgac and Sipahi for assessing the stabilityposture of a general class of linear time invariant–neutraltime delayed systems. The ensuing method, which is namedthe direct method, offers several unique features: It returnsthe number of unstable characteristic roots of the system in

    an explicit and non-sequentially evaluated function of timedelay, τ. Consequently, the direct method creates exclusivelyall possible stability intervals of τ [9].

    The DR vibration absorber has some attractivefeatures in eliminating tonal vibrations from the system[10]. Some of them are ability of real-time tune, perfecttonal suppression, wide range of frequencies, simplicity ofthe control implementation, and robust design [11].Additionally this single-degree-of-freedom absorber canalso be tuned to handle multiple frequencies of vibration[12]. Z. H. Wang and H. Y. Hu presented a systematic

    Table 1 Lumped spring-mass models

    Modeled asWorkpiece

    M2

    K3 C3

    K2 C2

    K1 C1

    Modeled M1

    K2 C2

    K4 C4

    Modeled asM3

    Ka Ca

    K4 C4K3 C3

    Modeled asDelay resonator Ma

    Ka Ca

    Cutting tool

    f0 sin( t)

    DR system

    Primary system

    C3K3

    K4

    M3

    M2

    Ma

    Ka Ca

    K2 C2

    C1

    M1

    K1

    C4

    a) b) Fig. 3 a Spring-mass model ofthe machine tool—DR attachedto the m3. b Machine tool,cutting tool, and workpiece

    Int J Adv Manuf Technol (2011) 56:879–891 881

  • method of stability analysis for high-dimensional dynamicsystems involving a time delay and some unknownparameters [13]. The term “unknown” means that theparameters are constants but yet to be determined. Theanalysis focuses on the stability switches of those systemswith increase of the time delay from zero to infinity. Onthe basis of the generalized Sturm criterion, the parameterspace of concern is divided into several regions deter-mined by a discrimination sequence and the Routh–Hurwitz conditions. It is found that as the time delayincreases, the system undergoes none, exactly one, ormore than one stability switches when the parameters arechosen from different regions [13].

    Takagi–Sugeno fuzzy model was extended by Chen-YuanChen to analyze the stability of interconnected systems withtime delays in their subsystems [14]. They present a stabilitycriterion in terms of Lyapunov’s theory for fuzzyinterconnected models [14]. The stabilization problem wasconsidered by F. H. Hsiao for a nonlinear multiple time-delay large-scale system [15]. They employed a neural-network (NN) model to approximate each subsystem of thelarge-scale system [15]. They established a linear differentialinclusion state space representation for the dynamics of eachNN model. Finally, a delay-dependent stability criterion wasderived to guarantee the asymptotic stability of the nonlinearmultiple time-delay large-scale systems.

    0 0.005 0.01 0.015 0.02 0.025 0.030

    0.005

    0.01

    0.015

    0.02

    τ (s)

    Gai

    n (K

    g)

    0 0.005 0.01 0.015 0.02 0.025 0.030

    500

    1000

    τ (s)

    ω (R

    ad/s

    )

    a)

    Zoom in

    DR alone

    Stable zone

    Combined system

    l = 1 l = 2 l =3

    DR alone

    Combinedsystem

    b)

    c)

    d)

    Fig. 4 Stability charts. a Plot ofgain versus time delay forcombined system and DR alone.b Plot of excitation frequencyversus time delay for DR alone.c A zoom of selected zoneshown in a. d A zoom ofselected zone shown in b

    m1 m2 m3 m4 k1 k2 k3 k4 ka C1 C2 C3 C4 Ca(kg) (N/m) (Nm/s)

    100 10 8 0.3 100e4 80e4 10e4 80e4 1e4 50 60 7 60 0.5

    Table 2 System parameters value

    882 Int J Adv Manuf Technol (2011) 56:879–891

  • In this study, our goal is to demonstrate that theundesirable vibration of a machine tool with specificworking frequency can be minimized by utilizing a DRand without altering the existing control system ormechanical structure of the machine. Therefore, a machinetool and a delay resonator are chosen to minimize therelative vibration between the cutting tool and workpiece.The DR is first attached to the cutting tool and next to theworkpiece. In both cases, the relative vibration during

    machining process are studied and reported in this paper. Adetailed flow chart depicting major steps carried out in thispaper is shown in Fig. 1.

    2 The delay resonator concept

    A brief overview of DR is presented here. DR has anunconventional control logic which is implemented on a

    0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1-1

    -0.5

    0

    0.5

    1x 10-3

    x 10-3

    x 3 (

    m)

    x 3 (

    m)

    Time (s)

    0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1-1

    -0.5

    0

    0.5

    1

    Time (s)

    a)

    b)

    Fig. 5 a Displacement of m3while g=0. b Displacement ofm3 while g≠0

    0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1-0.015

    -0.01

    -0.005

    0

    0.005

    0.01

    0.015

    x a (

    m)

    x a (

    m)

    Time (s)

    0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1-0.03

    -0.02

    -0.01

    0

    0.01

    0.02

    0.03

    Time (s)

    a)

    b)

    Fig. 6 a Displacement absorberwhile g=0. b Displacement ofabsorber while g≠0

    Int J Adv Manuf Technol (2011) 56:879–891 883

  • passive absorber. See Fig. 2a. It consists of a proportionalposition feedback with time delay. The position feedback canbe based on absolute or relative displacements of the absorber.These displacement measurements are prohibitively difficult

    for high frequency-low amplitude applications. Accelerationfeedback is much more feasible for such cases. See Fig. 2b.

    Naturally, the effects of substituting displacement mea-surements with acceleration should be carefully analyzed.

    0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1-3

    -2

    -1

    0

    1

    2

    3x 10 -4

    x 10 -3

    x 1 (

    m)

    Time (s)

    0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1-2.5

    -2-1.5

    -1-0.5

    00.5

    11.5

    22.5

    x 2 (

    m)

    Time (s)

    a)

    b)

    Fig. 7 a Displacement of m1,while g≠0. b Displacement ofm2, while g≠0

    0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1-3

    -2

    -1

    0

    1

    2

    3

    x 1 (

    s)

    Time (s)

    0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1-2.5

    -2

    -1.5

    -1

    -0.5

    0

    0.5

    1

    1.5

    2

    2.5x 10-3

    x 10-4

    x 2 (

    m)

    Time (s)

    a)

    b)

    Fig. 8 a Displacement of m1,while g=0. b Displacement ofm2,while g=0

    884 Int J Adv Manuf Technol (2011) 56:879–891

  • Using this feedback control converts the dissipative passiveabsorber structure into a marginally stable one, i.e., aresonator with a specified resonance frequency, ωc [12].

    Control goal is to place the dominant poles at ±ωj, wherej ¼ ffiffiffiffiffiffiffi�1p . Recommended force to achieve pole position isg � x��a t � tð Þ ð1Þwhere g is gain and τ is time delay. The corresponding newsystem dynamics is

    max��a þ cax� a þ kaxa � gx��a t � tð Þ ¼ 0 ð2ÞThe Laplace domain representation leads to the transcen-

    dental characteristic equation

    mas2 þ casþ ka � gs2e�ts ¼ 0 ð3ÞThis equation possesses infinitely many finite roots for g≠0

    and τ≠0. Their distribution can be sketched following the

    root locus analysis [13]. To achieve ideal resonator behavior,two dominant roots of Eq. 2 should be placed on theimaginary axis at the desired crossing frequency ωc whilethe others remain in the left half of the complex plane.Substituting S=±ωj into Eq. 3 and solving for the controlparameters gc and τc, one obtains

    gc ¼ 1wc

    2

    � � ffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffifficawcð Þ2 þ maw2c � ka

    � �2q ð4Þ

    tc ¼ 1wc

    � �tan�1

    cawcmaw2c � ka

    � �þ 2 L� 1ð Þp

    ; L¼ 1; 2; . . .

    ð5ÞThe variable parameter L refers to the branch of root loci

    that happens to cross the imaginary axis at ωc. Extensivestudies on stability analysis have been done previously [7–10].

    0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1-1.5

    -1

    -0.5

    0

    0.5

    1

    1.5x 10-4

    X3

    (m)

    Fig. 9 Control parameters areselected from unstable zone

    0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1-4

    -3

    -2

    -1

    0

    1

    2

    3

    4x 10-3

    x 1 (

    m)

    x 1 (

    m)

    Time (s)

    0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1-8

    -6

    -4

    -2

    0

    2

    4

    6

    8x 10-4

    Time (s)

    a)

    b)

    Fig. 10 a Displacement of m1without DR. b Displacement ofm1 with DR and gain ≠0

    Int J Adv Manuf Technol (2011) 56:879–891 885

  • 3 DR application on machine tool

    A mechanical system can be described by a lumped spring-mass model. Since an actual machine tool structure cannot beregarded as a system with proportional damping, generalviscous damping must be used to describe the behavior of the

    system. A typical machine tool, workpiece, cutting tool, andtime delay resonator with their lumped spring-mass models areexplained in Table 1. Equivalent masses of the machine tool,workpiece, and the cutting tool are represented by m1, m2,and m3, respectively. The delay resonator mass, ma, isattached to the cutting tool through a spring and a damper.

    0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1-4

    -3

    -2

    -1

    0

    1

    2

    3

    4x 10-3

    x 2 (

    m)

    x 2 (

    m)

    Time (s)

    0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1-8

    -6

    -4

    -2

    0

    2

    4

    6

    8x 10-4

    Time (s)

    a)

    b)

    Fig. 11 a Displacement of m2without DR. b Displacement ofm2 with DR and gain

    0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1-4

    -2

    0

    2

    4x 10-3

    x3 (

    m)

    Time (s)

    0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1-1

    -0.5

    0

    0.5

    1x 10-3

    x3 (

    m)

    Time (s)

    a)

    b)

    Fig. 12 a Displacement of m3without DR. b Displacement ofm3 with DR and gain

    886 Int J Adv Manuf Technol (2011) 56:879–891

  • The stiffness and damping of the machine tool, workpiece,cutting tool, and delay resonator are represented by k1, C1, k2,C2, k3, C3, and ka, Ca, respectively. Additional relationbetween the cutting tool and the machine tool can be modeledby using an additional set of spring and damper, as k4, C4.Four basic coordinates, x1, x2, x3, and xa are defined torepresent the 4-degree-of-freedom of the system.

    In milling process, an exciting force is generated betweencutting tool and workpiece. This force leads to additionalvibration in cutting tool, workpiece, andmachine tool. The goalof this study is to improve the quality of the milling process byreducing the vibration between cutting tool and the workpiece.

    Assembled model is shown in Fig. 3.The state space representation of the system dynamics is

    written in the form:

    y� ðtÞ ¼ A0yðtÞ þ gAt y� ðt � tÞ þ f ðtÞ ð6Þ

    Where, yðtÞ ¼fx1; x� 1; x2; x� 2; x3; x� 3; xa; x� ag and f ðtÞ ¼0; 0; 0� f ; 0; f ; 0; 0f g are state space variables and excitation

    force, respectively. Furthermore, the amplitude deflection of theprimary structure and absorber are denoted by xi, where i=1, 2,3, a. The parameters A0 and Aτ represent correspondingsystem matrices. These matrices are shown in Appendix.Finally, g and τ are gain and time delay, respectively. TheLaplace transform of Eq. 6 is

    sI � A0 � gse�tsAtð ÞY ðsÞ ¼ FðsÞ ð7ÞThe characteristic equation can be written as

    Qðs;g;tÞ ¼ sI � A0 � gse�tsAtj j ¼ 0 ð8ÞPoles of the system are those (complex) values of s for

    which sI � A0 � gse�tsAtj j is zero. For non-delay systems,these poles are the eigenvalues of the system matrix, A0.

    4 Stability analysis of the combined system

    The stability is an important property of any feedbackcontrol system. The sufficient and necessary condition forasymptotic stability is that the roots of the transcendentalcharacteristic Eq. 8 have negative real parts. The verifica-tion of the root locations, however, is not a trivial task. Thecharacteristic Eq. 8 can be written in a simplified form as

    X1k¼0

    HkðsÞgke�kts ¼ 0 ð9Þ

    One can obtain its most general form as

    Mðg;sÞþNðg;sÞge�ts ¼ 0; ð10Þwhere M and N are polynomials of s. When the combined(machine tools with DR on cutting tool) system is marginally

    stable, there are at least two roots on the imaginary axis.Enforcing S=±ωj into Eq. 10 and solving for the controlparameters gcs and τcs yields the delay and feedback valuesthat make the combined system marginally stable as

    gcs ¼ Mðg;sÞNðg;sÞ����

    ���� ð11Þ

    tcs ¼ ð 1wcsÞ 2ðl � 1Þp þ tan�1ðMðg;sÞ

    Nðg;sÞ Þ

    ð12Þ

    As shown in Fig. 4a and b, plots of gc versus τc and gcsversus τcs illustrate the stability points. Zoomed sections for aninterval containing operating frequency are shown in Fig. 4cand d. The ratio of the combined system gain and DR gain(gcs/gc) can be defined as the “stability margin” of the controlsystem, at the particular delay value τ. That is, for a given τc,the system is stable if gc

  • that for ideal suppression, the control must maintain the DRwithin the stability zone. As shown in Fig. 4c, this zone isbelow dotted lines and where gain of the DR is less than gainof the combined system (meshed zone).

    Clearly, the desirable values of the combined systemgain and time delay should be in the stable operating zones.Figure 4b shows the relation between the delay, τc, and thefrequency, ωc. For instance, the stable interval of τ given inexample above corresponds to 575

  • is based on the time-delay resonator, which is a tonalvibration absorber. Unlike previous studies which try toreduce the total machine tool structure vibration, thisresearch is concentrated on minimizing the cutting tooland the workpiece vibrations under simple sinusoidalexcitations. This approach is thus more realistic andaddresses the metal cutting excitation problem directlywith minimal computation efforts. What makes thismethod more advantages is its additive nature. Thismeans that its control logic is independent of thecontroller used in the machine tool. Furthermore, the

    additional mechanical components, DR, are added tothe system without altering the existing mechanicalstructure. Simulink model of the system is alsopresented. Results of this research indicate that theuse of DR technique for minimizing the vibrationsystem is highly efficient and effective. Results alsoshow that optimum location of DR is on the cuttingtool. This method can be expanded to more complexsystems with large DOF and multiple DRs. Theprocedure outlined can also be used as a design toolfor selecting the DR optimum parameters.

    Appendix

    x1

    TransportDelay1

    TransportDelay

    x2

    To Workspace3

    x1

    To Workspace2

    xa

    To Workspace1

    x3

    To Workspace

    Sine Wave

    Scope7

    Scope5

    Scope4

    Scope3

    Scope2

    Scope1

    Scope

    1s

    Integrator7

    1s

    Integrator6

    1s

    Integrator5

    1s

    Integrator4

    1s

    Integrator3

    1s

    Integrator2

    1s

    Integrator1

    1s

    Integrator

    -K-

    Gain9

    -K-

    Gain8

    -K-

    Gain7

    -K-

    Gain6

    -K-

    Gain5

    -K-

    Gain4

    -K-

    Gain3

    -K-

    Gain27

    -K-

    Gain26

    -K-

    Gain25

    -K-

    Gain24

    -K-

    Gain23

    -K-

    Gain22

    -K-

    Gain21

    -K-

    Gain20

    -K-

    Gain2

    -K-

    Gain19

    -K-

    Gain18

    -K-

    Gain17

    -K-

    Gain16

    -1Gain15

    -K-

    Gain14

    -K-

    Gain13

    -K-

    Gain12

    -K-

    Gain11

    -K-

    Gain10

    -K-

    Gain1

    -K-

    Gain

    x1dotdot

    x1dot

    x1dot

    x1dot

    x1dot

    x1dot

    x1

    x1

    x1

    x1

    x2dotdot

    x2dot

    x2dot

    x2dotx2dot

    x2

    x2

    x2x2

    xdot3

    xdot3

    xdot3

    xdot3

    xdot3

    x3

    x3

    x3

    x3

    xadotdot

    xadot

    xadot

    xa

    xa

    x3dotdot

    Fig. 13 MATLAB Simulink model—DR attached on m3

    Int J Adv Manuf Technol (2011) 56:879–891 889

  • A0 ¼

    � k1 þ k2 þ k4ð Þ=m1 � c1 þ c2 þ c4ð Þ=m1 k2=m1 c2=m1 k4=m1 c4=m1 0 00 1 0 0 0 0 0 0k2=m2 c2=m2 � k2 þ k3ð Þ=m2 � c2 þ c3ð Þ k3=m2 c3=m2 0 00 0 0 1 0 0 0 0k4=m3 c4=m3 k3=m3 c3=m3 � k3 þ k4 þ kað Þ=m3 � c3 þ c4 þ cað Þ=m3 ka=m3 ca=m30 0 0 0 0 1 0 00 0 0 0 ka=ma Ca=ma �ka=ma �ca=ma0 0 0 0 0 0 0 1

    0BBBBBBBBBB@

    1CCCCCCCCCCA

    x1

    TransportDelay1

    TransportDelay

    x2

    To Workspace3

    x1

    To Workspace2

    xa

    To Workspace1

    x3

    To Workspace

    Sine Wave

    Scope7

    Scope5

    Scope3

    Scope1

    Scope

    1s

    Integrator7

    1s

    Integrator6

    1s

    Integrator51s

    Integrator4

    1s

    Integrator3

    1s

    Integrator2

    1s

    Integrator1

    1s

    Integrator

    -K-

    Gain9

    -K-

    Gain8

    -K-

    Gain7

    -K- Gain6

    -K-

    Gain5

    -K-

    Gain4

    -K-

    Gain3

    -K-

    Gain27

    -K-

    Gain26

    -K-

    Gain25

    -K-

    Gain24

    -K-

    Gain23

    -K-

    Gain22

    -K-

    Gain21

    -K-

    Gain20

    -K-

    Gain2

    -K-

    Gain19

    -K-

    Gain18

    -K-

    Gain17

    -K-

    Gain16

    -1Gain15

    -K-

    Gain14

    -K-

    Gain13

    -K-

    Gain12

    -K-

    Gain11

    -K-

    Gain10

    -K-

    Gain1

    -K-

    Gain

    x1dotdot

    x1dot

    x1dot

    x1dot

    x1

    x1

    x2dotdot

    x2dotx2dot

    x2

    xdot3xdot3

    x3

    xadotdot

    xadotxadot

    xaxa

    x3dotdot

    Fig. 14 MATLAB Simulink model—DR attached on m2

    890 Int J Adv Manuf Technol (2011) 56:879–891

  • At ¼

    0 0 0 0 0 0 0 00 0 0 0 0 0 0 00 0 0 0 0 0 0 00 0 0 0 0 0 0 00 0 0 0 0 0 0 00 0 0 0 0 g=m3 0 00 0 0 0 0 0 0 00 0 0 0 0 0 0 g=ma

    0BBBBBBBBBB@

    1CCCCCCCCCCA

    References

    1. Tlusty G (2000) Manufacturing processes and equipment. PrenticeHall

    2. Shin YC, Wang KW (1991) Design of an optimal damper tominimize the vibration of machine tool structures subject torandom excitation. J Eng Comput 9:199–208

    3. Pratt JR (1997) Vibration control for chatter suppression withapplication to boring bars. PhD. Dissertation, pp 40–83

    4. Hosek M, Elmali H, Olgac N (1997) A tunable torsional vibrationabsorber: the centrifugal delayed resonator. J Sound Vib 205:151–165

    5. Olgac N, Jalili N (1998) Modal analysis of flexible beams withdelayed resonator vibration absorber: theory and experiments. JSound Vib 218:307–331

    6. Åkesson H (2007) Active control of vibration and analysis ofdynamic properties concerning machine tools. PhD. Dissertation,Blekinge Institute of Technology, pp 27–91

    7. Rojas J, Liang C, Geng Z (1996) Experimental investigation ofactive machine tool vibration control. Proc SPIE Smart StructMater 2721:373–384

    8. Hosek M, Olgac N (2002) A single-step automatic tuning algorithmfor the delayed resonator vibration absorber. IEEE J TransMechatron7:245–255

    9. Sipahi R, Olgac N (2006) A unique methodology for the stabilityrobustness of multiple time delay systems. Syst Control Lett55:819–825

    10. Olgac N, Holm-hansen B (1994) A novel active vibrationabsorption technique: delayed resonator. J Sound Vib 176:93–104

    11. Jalili N, Olgac N (1999) Multiple delayed resonator vibrationabsorbers for multi degree of freedommechanical structures. J SoundVib 223:567–585

    12. Olgac N, Hosek M (1996) Active vibration absorption usingdelayed resonator with relative position measurement. ASME JVib Acoust 119:131–136

    13. Wang ZH, Hu H (2000) Stability switches of time-delayeddynamic systems with unknown parameters. J Sound Vib 233(2):215–233

    14. Chen CY (2005) Fuzzy logic derivation of neural network modelswith time delays in subsystems. Int J Artif Intell Tools 14:967

    15. Hsiao FH, Chen CW, Liang YW, Xu SD, Chiang WL (2005) T-Sfuzzy controllers for nonlinear interconnected systems with multipletime delays. IEEETrans Circuits Syst-I: Regular Pap 52(9):1883–1893

    Int J Adv Manuf Technol (2011) 56:879–891 891

    Application of time delay resonator to machine toolsAbstractIntroductionThe delay resonator conceptDR application on machine toolStability analysis of the combined systemDynamic simulations and resultCase study—ICase study—II

    ConclusionAppendixReferences