Where innovation starts Where innovation starts Industrial Applications of Learning Control Maarten Steinbuch Symposium on Learning Control at IEEE CDC 2009 Shanghai, China 1
Focus and Background 1. Optical storage devices 2. Advanced Motion Systems (Wafer Scanners) Philips Research & Philips AppTech ASML Eindhoven and Delft University of Technology People: Schootstra, Sperling, van Baars, Tousain, van de Wal, Bosgra, Dijkstra, de Rover, van de Wijdeven, Oomen, Heertjes, Rotariu, Groot Wassink, Hennen, Witvoet, Merry, van Berkel, Steinbuch, and many MSc students 2
Optical Storage Case 1: Standard repetitive control Case 2: High Order repetitive control Case 3: Lifted ILC for reading cracked discs 3
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Gunter Stein s Bode Lecture, CDC 1989 IEEE Control Systems Magazine, 23 (2003), pp 12-25 5
how to cope with Bode sensitivity limitation? 0 log S( jω) dω = 0 6
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Case 1: Standard repetitive control Nominal servo error signal 8
A Principles of repetitive control Introduction Periodic signal generator: memory loop 1 F K J K J F K J I = F A I 6 I I A? @ I I = F A I 6 I I A? @ I Magnitude (db) 200 180 160 140 120 100 80 60 40 20 0 10 20 30 40 50 60 70 Frequency (Hz) 9
Standard repetitive control e + + z -N Q L z r + e - Repetitive Controller + z + C u P d + y L = learning filter: L = k T Q = robustness filter (low pass FIR filter) r 1 PC T = 1+ PC 10
Model CD-player system Frequency response of the cd-player system (radial tracking loop) 100 Magnitude [db] 50 0 50 10 1 10 2 10 3 10 4 Phase [deg] 400 200 0 200 400 Measured 6th order fit 600 10 1 10 2 10 3 10 4 Frequency [Hz] 11
Open loop CD-player system Open loop frequency response (without repetitive controller) Magnitude (db) Phase (deg) 150 100 50 0 50 10 0 10 1 10 2 10 3 10 4 Frequency (Hz) 100 200 300 400 500 10 0 10 1 10 2 10 3 10 4 Frequency (Hz) 12
Learning filter Cd-player system Magnitude [db] 40 30 20 10 0 Frequency response L-filter 1 L = T ZPETC 10 10 0 10 1 10 2 10 3 10 4 Phase [deg] 150 100 50 0 50 10 0 10 1 10 2 10 3 10 4 Frequency [Hz] 13
Robustness filter CD-player system Q = 200 th order 200 Hz, FIR 1 lowpass filter Frequency response Q-filter Linear phase: Magnitude [db] 0 20 40 60 80 100 10 0 10 1 10 2 10 3 Q jω ( e ) = jqωts 1 D 23 (ω) e213 phase magnitude 0 Phase [deg] 200 400 600 800 0 200 400 600 800 1000 Frequency [Hz] 14
Standard repetitive control Servo only With repetitive 15
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Case 2: High Order Repetitive Control Period +0.5% 17
High order repetitive control e z -N z -N z -N w p Q L z w 2 w 1 Open loop transfer function: M Infinite gain at repetitive frequency Constraint: p in wi z z p i= 1 ( z) = = p e w i in 1 wi z i= 1 i= 1 = 1 18
High Order Repetitive Control Period +0.5% With N=2 19
RC-TU/e References -1 M. Steinbuch, Repetitive control for systems with uncertain period-time, Automatica, 38(12), 2103-2109, (2002) M. Steinbuch, S. Weiland, T. Singh, Design of noise and period-time robust High Order Repetitive Control, with application to Optical Storage, Automatica, 43(12), 2086-2095, (2007) G. Schootstra, M. Steinbuch, Control system for a process that exhibits periodic disturbances, Patent: 5784272 (1998) M. Steinbuch, G. Schootstra, Filter, repetitive control system and learning control system both provided with such filter, Patent: 5740090 (1998) 20
Case 3: Lifted ILC for reading cracked discs z outer edge x label side x: radial y: tangential z: focus laser beam y outer edge read-out side z y crack data spiral laser spot x 21
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System description Optical drive Philips BD1 Motion system (lens & actuator) Approx. 2 nd order mass-spring-damper system Magnitude [db] 60 40 20 0 20 Bode diagram: focus open loop y z sim meas x Feedback controller Tame PID with noise filter 40 0 50 100 10 3 10 4 sim meas Phase [deg] 150 200 250 300 350 10 3 10 4 Frequency [Hz] 23
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ILC principles (1) Timing Hankel ILC Hankel ILC observation after actuation Tracking error unreliable observation For reading cracked discs: observe after crack actuate during crack Actuator input actuation crack interval Time 25
ILC principles (2) r drive γl f k J - + e k Learn feedforward Actuate plant E k z -1 E + I k+1 + e 0,k K Update trial states Obtain initial states controller 26
Application (1) Unreliable tracking error during crack Switch off feedback controller during crack. actuation in open feedback loop (o.l.) system observation in closed feedback loop (c.l.) system Reconstruct o.l. error from the observed c.l. error. A/D-conversion Aliasing Actuator saturation during observation, due to feedback control during actuation, due to feedforward control (ILC) 27
Applied learning loop r γ L f k D/A + e k J - S A/D S -1 drive with feedback loop switch g k ~J ε k E k E z -1 + I k+1 + ε 0, k e 0,k K 28
Measurement results (1) 29
Measurement results (2) 30
RC-TU/e References -2 M. Steinbuch, K. van Berkel, G. Leenknegt, T.A.E. Oomen, J.J.M. van de Wijdeven, Reading of Cracked Optical Discs Using Iterative Learning Control, in Proceedings of the 2009 American Control Conference; Saint Louis, MO, United States, 258-263, (2009) M. Steinbuch, J.J.M. van de Wijdeven, T.A.E. Oomen, K. van Berkel, G. Leenknegt, Recovering Data from Cracked Optical Discs using Hankel Iterative Learning Control, in Model-Based Control: Bridging Rigorous Theory and Advanced Technology; Editors: Paul M. J. Van den Hof, Carsten Scherer, and Peter S. C. Heuberger, 147-166, Springer, Book Chapter 978-1-4419-0894-0 (2009) Further results from the group on repetitive: R.J.E. Merry, Performance driven control of nano-motion systems, PhD. Thesis, 2009, TU/e Advisors: M. Steinbuch, Co-advisor: M.J.G. van de Molengraft R.J.E. Merry, D.J. Kessels, M.J.G. van de Molengraft, M. Steinbuch, Repetitive control applied to a walking piezo actuator, in International Conference on Control & Automation; Christchurch, New Zealand, 6 pages, (2009) D. de Roover, O.H. Bosgra, M. Steinbuch, Internal model based design of repetitive and iterative learning controllers for linear multivariable systems, Int. J. of Control, 73(10), 941-929, (2000) 31
Advanced Motion Systems (wafer scanners) Case 1: Standard ILC Case 2: Varying Setpoints 32
IBM Power PC: the interconnect complexity, Polygate 0.12 um Source: ICE 33
Global layout lithography tool Light source + light shaping Reticle for pattern generation Lens for 4:1 reduction image of the reticle to the wafer Wafer on wafer stage 34
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Case 1: Standard Iterative Learning Control (ILC) Q ( 1 L PS ) < 1 40
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LPS 46
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Illustration of finite time problem ILC - trajectories 50
ILC - error trial 1 51
ILC - error trial 1 (zoom in) 52
ILC - error trial 6 53
ILC - feedforward trial 6 54
ILC design procedure Define repeating tasks Pick-place actions Motion scans Portions of scans! acc time Essential question: What is the nature of the repeating disturbance? (compare e.g. the nature of a setpoint disturbance vs. cogging) time time 55
ILC design procedure (ctd.) Define the control and observation window Ncont (Motion stage example) Nobs Ncont=250, Nobs=450 (samples) 56
Lifted system time weight ILC I 0 W1 = 0 0 W 1 0 0 = 0 I Time weights! yˆref H 2 Iterative Learning Controller xˆk W W1 H 1 2 + eˆk 57
Input ILC error trial 1 58
Input ILC error trial 5 59
Input ILC feedforward trial 5 60
ILC-TU/e References - 1 J.J.M. van de Wijdeven, M.C.F. Donkers, O.H. Bosgra, Iterative Learning Control for uncertain systems: Robust monotonic convergence analysis, Automatica, 46(tbd), accepted, (2010) J.J.M. van de Wijdeven, O.H. Bosgra, Using basis functions in Iterative Learning Control: Analysis and design theory, Int. J. of Control, 83(tbd), accepted, (2010) T.A.E. Oomen, J.J.M. van de Wijdeven, O.H. Bosgra, Suppressing Intersample Behavior in Iterative Learning Control, Automatica, 45(4), 981-988, (2009) I. Rotariu, M. Steinbuch, R.M.L. Ellenbroek, Adaptive Iterative Learning Control for high precision motion systems, IEEE Trans. on Control Systems Techn., 16(5), 1075-1082, (2008) S.H. van der Meulen, R.L. Tousain, O.H. Bosgra, Fixed Structure Feedforward Controller Design Exploiting Iterative Trials: Application to a Wafer Stage and a Desktop Printer, J. Dynamic Systems, Measurement and Control, 130(5), 051006, (2008) R.J.E. Merry, M.J.G. van de Molengraft, M. Steinbuch, Iterative learning control with wavelet filtering, Int. J. of Robust and Nonlinear Control, 18(10), 1052-1071, (2008) 61
ILC-TU/e References - 2 J.J.M. van de Wijdeven, O.H. Bosgra, Residual vibration suppression using Hankel Iterative Learning Control, Int. J. of Robust and Nonlinear Control, 18(10), 1034-1051, (2008) O.H. Bosgra, Book Review: Multivariable Feedback Control - Analysis and Design, Skogestad & Postlethwaite, IEEE Control Systems Magazine, 27(1), 80-81, (2007) B.H.M. Bukkems, D. Kostic, A.G. de Jager, M. Steinbuch, Learning-Based Identification and Iterative Learning Control of Direct-Drive Robots, IEEE Trans. on Control Systems Techn., 13(4), 537-549, (2005) J.J.M.van de Wijdeven, Iterative Learning Control design for uncertain and time-windowed systems, PhD. Thesis, 2008, TU/e Advisors: O.H. Bosgra, M. Steinbuch I. Rotariu, R.M.L. Ellenbroek, M. Steinbuch, G.E. van Baars, Method of adaptive interactice learning control and Apparatus employing such a methodol and a Lithographic Manufacturing, Patent: 43834 (2005) I. Rotariu, R.M.L. Ellenbroek, M. Steinbuch, G.E. van Baars, Method of Adaptive Iterative Learning Contr Process and Apparatus employing such a methodol and a Lithographic Manufacturing, Patent: 30774616 (2004) 62
Recent work/other applications ILC for a UHP Lamp (Philips Lighting) power electronics inkjet printing piezo actuator paper handling in printing actuation for repeated scanning for calibration AFMs MHD control in burning plasma (nuclear fusion) 63
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Future Challenges Computational issues LPV type systems Relation with identification Robustness and many other applications 67
Thank you for the attention! 68