47 Joural of Sciece ad Egieerig Techology, Vol. 1, No., pp. 47-56 (005) 11 Matlab DSP Parameter Desig Automatio for a Focusig Cotrol System o a CD-OM Player YIH-FANG CHANG ad WEY-LIAN CHEN Departmet of Mechaical ad Automatio Egieerig, Da-Yeh Uiversity 11 Sha-Jiau d., Da-Tsue, Chaghua, Taiwa ABSTACT A automatic parameter desig process is developed for a lead-compesator i a focusig cotrol system o a commercial optical disk drive. I the frequecy domai the automatic desig process of focusig a pick-up head cotroller ca apply a set of cotrol parameters to the lead compesator, desiged by Matlab software to provide a coveiet ad fast operatio. After the actual system parameters are idetified by a auxiliary experimet, the appropriate cotrol parameters ca be obtaied ad the hex code for the digital sigal processor (DSP) o the player geerated by the proposed automatic desig program. The practical performace of the cotrol system ca be improved via the desig process. Key Words: lead compesator, focusig cotrol system, CD-OM
48 lead compesator Matlab opto-mechaical actuator digital sigal processor, couplig DSP ucertaity 1. Chait [10] QFT quatitative feedback theory template 1 [,4] performace boud stability time costat boud loop τ e = L shapig template U(s) idetificatio error X(s) [5] KV X ( s) K f = U ( s) M + B L M c KV f. Steibuch [14] s + ( + ) s + 1 K f K f K f µ-sythesis KV = 1 KV Ms + ( B f + ) s + K f Disc L Objective Les adial Directio i Sled Focusig Directio U Vm 1. [,4]
49 f = K i K v v K f M L M c B f M M L M C 1 X U K m = s + ξω s + ω ξ dampig ratioω atural frequecy K m (a) E = (V A +V B )-(V C +V D ) = 0 astigmatism [1] 3. [1] CD AB (b) E = (V A +V B )-(V C +V D ) < 0 0V E=0 (c) E = (V A +V B )-(V C +V D ) > 0 3(a) [1] E=V A +V B -V C +V D = 0 3 3. [1] 3(c) AB E>0 CD E<0 E=V A +V B -V C +V D > 0 5 3(b) E = V A +V B -V C +V D < 0 4 3 5 E Y r CD
50 E = Y r 6 + Y lead-lag compesator 5. 4 ( k + k ) k1 + kz k4 + k5z C H ( z) = 7 8z 7 k3z k6z ( k + k ) k9 + k10z C M ( z) = 1 13z 8 k11z ( k + k ) k14 + k15z C L ( z) = 17 18z 9 k16z k 1 k 8 C H (z) k 9 k 13 C M (z) k 14 k 18 C l (z) 4 K c k 1 k 18-1 +1 K c 3 sie wave HP35670 A/D FEI FOSO D/A C M (z) C L (z) gai phase [13] system idetificatio C M (z) C L (z) C H 5 G c (z) 4 G c (z) 1 FEI C (z) H 88.KHz C (z) M = 44.1KHz C (z) L =.05KHz FOSO K c + + 4. CD_OM G c (z) r(s) _ FEO FEI A/D G (z) c U (s) =FOSO D/A -K m s + ξ ω s + ω + + d 5 d [3, 6, 7, 9] FOSO FEO 6 [8, 15] source CH1 CH 7 X(s)
51 sweep sie spa:10hz - 10kHz source _ + Vref Vref _ + FEI DSP (MT1198AE) FOSO FOSO BA5918FP FOCUS Actuator optical sesor HP35670 source CH1 CH kw k s s + y ws+ s y w source FOSO FEO FEO FEO (MT1136AE) 6. [13] 7. curve fittig 49.3441dB G c (z) 1 ξ 0.1515 platk m ω 396rad/s k=93.85
5 G c (s) X ( s) U ( s) k = m 10 s + ξω s + ω = s kω 93.85 396 = + ξω s + ω s + ( 0.151 396) s + 396 d ω G ope( s) = 11 s + ξωs + ω d E=0 d. % O sd Tpd 5 4 10 8 8 r+d d l(% Osd /100) ξ d = 1 r+d d π + l (% Osd /100) ξ d ΦMd = ta 13 4 ξ d + 1+ 4ξ d Bode plot 9 KHz %O sd %O sd0 d= r+d U (s) 93.85 ω G c(s) + _ s + ξ ω s + ω X(s) ΦM phase margi overshoot gai crossover frequecy [11-13] 10 1. G c (s)=1 E X ξ d ΦMd %O sd 8. 5. maxgcs %Osd=%Osd-1 1. G opes 6. G cs Gs Tfs. %O sd %O sd0 T pd (1) d Md () bw 7. %O s %O s>%o sd0? yes 3. G ope (s) 1 Mi i o 8. G cs 4. 0log(1/ ) db max 9. ξ = 0.151, ω = 396rad / s 10.
53 ξ ω 4 bw = d d d d d ω ω (1 ξ ) + 4ξ 4ξ + 14 ω d π = 15 Tdp ξd bw %O s %O s %O sd0 %O s %O sd0 %O s %O s > %O sd0 %O sd0 %O s %O sd0 8. %O s %O sd0 Tusti S-domai Z-domai ) G c (s G ope (s) ΦMi ωi performace β siφ β = 16 1+ siφ max max 0.9359 0.9359z 0.9359 0.9318z 0.6119 + 0.6119z 0.0391z 0.9961z 0 φ max = ΦMd Φ Mi 17 0.500 + 0z 4. C M ( z) = ( 1+ z ) 1 0z 1 0log( ) db ωmax β 0.813z 0.480z C L ( z) = ( 0.573 + 0.573z ) 0.867z 1 s + 1 5. G c (s) = T β s + 1 βt [%O S =1 K c =3ξ 1 T = 18 ω β max 6. G c (s) G(s) T f (s) 1 s + ωh ω X β s + ωl s + ξω ( ) s + ω T f s = = 19 1 s + ω 1 h ω + β s + ω l s + ξωs + ω 7. % O s T f Matlab 0.7197 0.704z C H ( z) = 3 0.4435z % O s C H (z) -1 +1 C H (z) = = ( ) 0.151 ω 396( rad / s) ] 11 1 K c =3, k1 ~ k 18 +1 ~ -1 Tusti C H (s) Z-domai
54 11. 13. 1. 14. 3768 8000 16 7 k 1 =5C0 16 /8000 16 k =A619 16 /8000 16 k 3 =38C6 16 /8000 16 5C0 16 A619 16 38C6 16 Mtkflash 3.64KHz 15 13 16 mm 5000 rpm 14 G c (s)g(s)
55 T T > 1) Ch 1: 500 mvolt 1 ms 1 ) ef A: 500 mvolt 1 ms 17. 15. 1. Matlab. 3. 16. 0 17 3 17 S/N
56 implemetatio of a QFT cotroller for a compact disc player. Proceedigs of the America Cotrol Coferece, 1. 78 Baltimore, Marylad. -9 11. Choi, I. M., S. H. Kim ad Y. K. Kwak (1999) Desig ad. 78 cotrol of trackig actuator for optical disk. Proceedigs of 18-6 the 1999 IEEE/SJ Iteratioal Coferece o Itelliget 3. 87 obots ad Systems, Kyogju, Korea. 1. Haselma, D. C. ad B. C. Kuo (1995) MATLAB Tools 4. 88 5 for Cotrol System Aalysis ad Desig, 184-193. Pretice Hall, New Jersey, NJ. 189-197 13. Nise, N. S. (000) Cotrol Systems Egieerig, 684-710. 5. 75 Joh Wiley & Sos, New York, NY. 14. Steibuch, M., G. Schootstra ad O. H. Bosgra (199) 6. 78 obust cotrol of a compact disc player. Proceedigs of 7-31 the 31st IEEE Coferece o Decisio ad Cotrol, 7. 88 Tucso, Arizoa. 15. Yeh, T. J. ad Y. C. Pa (000) Modelig ad 8. 83 idetificatio of opto-mechaical couplig ad backlash oliearity i optical disk drives. IEEE Trasactios o 1 7-10 Cosumer Electroics, 46(1), 105-115. 9. 88 (1) 88-96 10. Chait, Y., M. S. Park ad M. Steibuch (1994) Desig ad 93.07.08 93.10.18 93.10.1