A generalized modal shock spectra method for spacecraft loads analysis

Unlike an e a r l i e r shock spec t ra approach, t he genera l iza t ion presented i n t h i s paper permits an a c c ~ r a t e e l a s t i c i n t e r a c t i o n between t h e spacecraf t and launch vehicle t o obtain accurate bounds on t h e spacecraf t response and s t r u c t u r a l loads. In addi t ion , t h e modal response from a previc.11~ launch vehicle t r a n s i e n t ana lys is with o r without a dummy spacecraf t i s exploi ted t o def ine a m ~ d a l impulse as a simple idea l i za t ion of t h e ac tua l forcing function. The idea l ized modal forcing function i s then used t o der ive e x p l i c i t expressions f o r an estimrrte of t h e bound on t h e spacecraf t s t r u c t u r a l response and forces . Greater accuracy i s achieved with t h e present method over t h e e a r l i e r shock spec t ra , while saving much computational e f f o r t over t h e t r ans i en t ana lys is . OVF,RVIEW I1-1 A. PACK(;Il()[JND 1 -1 1. Tr-ans ien t A n a l y s i s 1-1 2. A l t e r n a t e s t o T r a n s i e n t Ana lys i s 1-1 3. Retduued T r a n s i e n t ~ I r i a l y s i s Ps4ct,h, L -.> L~ IV. C. DETERMTNA!I11ON OF' THE 1 It IrI'IAL, Pl(iIV4 I . VGl,(ic'TTY v ---0 e 3-11~ 1. Es t ima te of v From the I.loda! Response oe 3-1 3 2. I k t i m a t e of' v F'rom P h y s i c a l 1nt.er't'ace 0 e Response 3-16 SPACECRAFT MEMBER LOADS , DI SFI,ACF:ME:I\IT: : , AND ACCELERATION 11-1 CONTENTS (cont inued)