(mov<strong>in</strong>g cutt<strong>in</strong>g force), represents the forced vibrations of the system ϕ 2* **and ϕ 2accord<strong>in</strong>gly, which is represented as follows:* **ϕ 2 = ϕ2+ φ2(2.9)*M ywhere( ( ) [( 2)]J n p pp 22 = ω − s<strong>in</strong> pt − 2 np cos2 2 2 24 + ω −pt**ϕ , (2.10)o**ϕ 2 = A + Bt + C s<strong>in</strong> ω t + D cos ω t + Et s<strong>in</strong> ω t + Kt cos ω t , (2.11)where2 *2 2 *2N = 4nω + ( ω − ω ) 2F r u, B = −2 ,J2 *2 2 *2*2 2 *2( ω − ω ) 2n( ω − ω ) F u 4nω( ω − ω )3 *2*2FalaFau8nω Fau4nωFauC = ++−+ ,J N2222oJ o NJ o NJ o N J o N26*o ω2 *2* 2 *2( ω − ω ) F u 2ω( ω − ω )* 2 * 2 *3 2 *Fal2nω4nω Fau8nω Fau4nωaFauD = − − −−+,J N2222o JoN JoNJoNJoNF uEa*= −F, au2nωJoNK = (2.12)JoNAdd<strong>in</strong>g the general solution (Eq. (2.8)) and partial solution (Eq. (2.9)–(2.12)), ageneral solution of the differential equations for the decl<strong>in</strong>ation angle of the blankϕ = exp( −nt )( C1 cos ω1t+ C 2 s<strong>in</strong> ω1t) +M y2 2+ω − p s<strong>in</strong> pt − 2npcos pt +2 2 2 2J 4np + ω − p(2.13)o+ A +( ( ) [( )]****Bt + + C s<strong>in</strong> ω t + D cosωt + Et s<strong>in</strong> ω t + Kt cos ω t,Tak<strong>in</strong>g <strong>in</strong>to account the <strong>in</strong>itial conditions ϕ ( 0) = ϕ &0ϕ(0)= & ϕ , the constants of0<strong>in</strong>tegration3* 2 *nmp y0Frl2nFruFal2nω4nω FauC1= ϕ0+− − + + +2 2 2 22 42J ( 4 ( )J Non p + ω − p Joωω Jo o JoN2 *32 * 2 *2* 2 *28nω Fau4nω ( ω − ω ) Fau2ω( ω − ω ) Fau++−,222J NJ NJ NCϕnCo3 2 2mp y0( ω − p )−+2 2 2 22Joω1( 4np + ( ω − p) Jo2 *2*3 2 *2( ω − ω ) F u 4nω( ω − ω )oω F lo2 *2( ω − ω )**0 1raa2= & +−−2ω1ω1ω ω1JoNω1ω1JoN*3 *3*3ω 2naFau8nω Fau4nωFau−−+ −2222ω1JoNω1JoNω1JoNω1JoN(2.14)F u*2nωF uF<strong>in</strong>ally the displacement y = ϕland the rotation speed ν of the blank end <strong>in</strong>relation to <strong>in</strong>itial conditions y 0 and v 0 should be found from Eq. (2.13).
is2.5. Dynamical model with two degrees of freedom2.5.1. Dynamical model with two degrees of freedom without damp<strong>in</strong>gThe differential equations of forced vibrations, caused by the cutt<strong>in</strong>g force F,accord<strong>in</strong>g to the theorem on k<strong>in</strong>etic moment, are presented <strong>in</strong> the follow<strong>in</strong>g form:2J0 & z&− Aω by&+ kzzl= Mzls<strong>in</strong>pt,2*J0& y+ Aω b z&+ k y yl = M ylcos pt + Frl1l+ Fal1lcosωt , (2.15)where ω * the angular velocity of blank rotation, 2M mp y l / 2ωy = b and2Mz= mp zbl/ 2 , y b and z b are the amplitudes of the foundation vibrations, k z andk y are spr<strong>in</strong>g constants, and A is the moment of <strong>in</strong>ertia of the blank <strong>in</strong> relation to theaxes of rotation.The general solution of Eqs (2.15) represents free vibrationsy1= a1s<strong>in</strong>( p1t+ α1)+ a2s<strong>in</strong>( p2t+ α2) ,(2.16)z1= µ1a1s<strong>in</strong>( p1t+ α1)+ µ2a2s<strong>in</strong>( p2t+ α2)where a 1 , a 2 , α 1 and α 2 are constants of <strong>in</strong>tegration to be determ<strong>in</strong>ed from the<strong>in</strong>itial conditions, µ 1 and µ 2 are ratios of the amplitudes of the two pr<strong>in</strong>cipalmodes of vibrations, p 1 and p 2 are the natural frequencies of vibrations withgyroscopic forces:22 2 22( J l ( k + k ) + A ) ± J l ( k + k )2 2 2 2 4 ⎞( 0 y z + A b ) − 4J0 l k y k z 0. J 0⎛p1,2= ⎜0 y z bω⎟ 5⎝⎠ω (2.17)Our analysis shows that with an <strong>in</strong>crease <strong>in</strong> the value of ω b the difference betweenthe higher and the lower frequencies, p 1 and p 2 , is <strong>in</strong>creased.It was found that for the first mode with the higher frequency p 1 , the ratio µ 1 waspositive, i.e. their vibrations y 1 and z 1 were <strong>in</strong> phase or <strong>in</strong> the so-called directprecession. For the lower frequency p 2 , their vibrations y 2 and z 2 were <strong>in</strong> theopposite phase or <strong>in</strong> the so-called reverse precession. In the first mode of vibration,a po<strong>in</strong>t of the blank axis moves along the circle <strong>in</strong> the direction of its own rotation,while <strong>in</strong> the second mode it moves <strong>in</strong> the direction opposite to rotation.A particular solution of Eqs (2.8), depend<strong>in</strong>g on the disturb<strong>in</strong>g force, representsthe forced vibrations of the system, which are represented as follows:whereB=*y2 = B cos pt + b cosω t + Fr l1/ k yl, (2.18)2 2M z l pA ω b − M y l ( k z l − J o p ),2 2 2 2 2 2 2p A ωb − ( k y l − J 0 p )( k z l − J 0 p )2 2M z l ( k y l − J o p ) − M y l p ω b2 2 2 2 2 2 2( k l − J p )( k l − J p ) − p A ωD = ,z 0 y 0b27
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- Page 7 and 8: Paper I............................
- Page 9 and 10: XII. Riives, J., Papstel, J., Otto,
- Page 11 and 12: 1. INTRODUCTION1.1. BackgroundManuf
- Page 13 and 14: database by a query; c. Search of t
- Page 15 and 16: Porter’s Diamond Model task an on
- Page 17 and 18: Figure 2.1 Use of modelling in prod
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- Page 21 and 22: Figure 2.6 Depth of field/magnifica
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- Page 25: uFy=ybsinptyOl 1ulFAϕFigure 2.10 C
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- Page 33 and 34: Analogically, test results and resu
- Page 35 and 36: Figure 3.1 Model checking in an ope
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- Page 39 and 40: Figure 3.5 FMS at TUTM9M8M4M1M2M7M5
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- Page 43 and 44: 4. MODELS FOR MONITORING THE RESOUR
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- Page 59 and 60: 1. Tehnoloogiaseadme tasemel on loo
- Page 61 and 62: REFERENCESAltintas, Y. (2000). Manu
- Page 63 and 64: Russo, M.F. (1999). Automating Scie
- Page 65 and 66: Paper IIAryassov, G., Otto, T., Gro
- Page 67 and 68: Paper IVOtto, T., Papstel, J., Riiv
- Page 69 and 70: ELULOOKIRJELDUS (CV)1. IsikuandmedE
- Page 71 and 72: CURRICULUM VITAE (CV)1. Personal da
- Page 73 and 74: DISSERTATIONS DEFENDED ATTALLINN UN