1.053/ 2.003 Dynami csandConr to lI Fal l2007 Probl em Set9 Out: Tue s day ,Nove mbe r27th,2007 Due : Monday ,De ce mbe r3rd,2007 Eq ui l i bra i, l i nearz iat i on,andst abi l i t y 1. Probl em 1 Adi s c ofmas sm andr adi usr i ss andwi che dbe twe e na hor i z ontals ur f aceanda s l e nde rr odofmas sm whi chcans l i dei nandout ofa hor i z ontalgr oovewi thout f r i cti onass howni nFi gur e1. Thedi s c rol l swi t houts l i p page wi thr e s pe ct toboth thehor i z ontalbottom aswe l lasther od. Ther odi sconne cte dtoa s pr i ngofa s pr i ngcons tant k ass howni nthef i gur e ,andtheothe re ndofthes pr i ngi s attache dtothei ne r ti alf r ame . As s umes omel e ngthL0 oftheun-s tr e tche ds pr i ng (al thoughthat wi l ltur nout tobei r r e l e vant tothepr obl e m). Ther odi spul l e dout ofthegr ooves uchthat thes pr i ngi ss tr e tche dbys omel e ngthandthe nr e l e as e d. a. De r i ve the e quati on ofmoti on ofthe s y s te m us i ng the Lagr angi an appr oach. b. Fi ndthee qui l i br i a ofthes y s te m. c. Li ne ar i z e the e quati on ofmoti on about the e qui l i br i um poi ntsand e xami nethes tabi l i tyofthee qui l i br i a. Fi gure1 Cite as: Sanjay Sarma, Nicholas Makris, Yahya Modarres-Sadeghi, and Peter So, course materials for 2.003J/1.053J Dynamics and Control I, Fall 2007. MIT OpenCourseWare (http://ocw.mit.edu), Massachusetts Institute of Technology. Downloaded on [DD Month YYYY]. 2. Probl em 2 Adi s c ofmas sm andr adi usr r ol l swi thout s l i ppi ngonani ncl i newhi chi sat angl e� wi thr e s pe ct tothehor i z ontalass howni nFi gur e2 be l ow. As pr i ngofa s pr i ngcons tant k i sconne cte dtoa f i xe ds uppor t anda pi vot at thece nte rofthe l ythedi s ci she l ds uch di s c ass howni nthef i gur e . Notethat gr avi tyacts .I ni ti al that thes pr i ngi sun-s tr e tche d. Thedi s ci sthe ns udde nl yr e l e as e d. I ts tar tsr ol l i ng wi thout s l i ppi ngonthei ncl i ne . a. De r i vethee quati onofmoti onofthes y s te m. b. Fi ndthee qui l i br i a ofthes y s te m. c. Li ne ar i z e the e quati on ofmoti on about the e qui l i br i um poi ntsand e xami nethes tabi l i tyofthee qui l i br i a. Fi gure2 Cite as: Sanjay Sarma, Nicholas Makris, Yahya Modarres-Sadeghi, and Peter So, course materials for 2.003J/1.053J Dynamics and Control I, Fall 2007. MIT OpenCourseWare (http://ocw.mit.edu), Massachusetts Institute of Technology. Downloaded on [DD Month YYYY]. 3. Probl em 3 Cons i de rthes y s te ms howni nthef ol l owi ngf i gur easi nPr obl e m 2 ofExam 2. You mayus ethee quati onofmoti onf r om thes ol uti onspos te donl i ne . a. Fi ndthee qui l i br i a ofthes y s te m. b. Li ne ar i z ethee quati onofmoti onabout thee qui l i br i um q=0 ande xami ne thes tabi l i tyofthi se qui l i br i um (ony). l g m, l k C k M, R Fi gure3 Cite as: Sanjay Sarma, Nicholas Makris, Yahya Modarres-Sadeghi, and Peter So, course materials for 2.003J/1.053J Dynamics and Control I, Fall 2007. MIT OpenCourseWare (http://ocw.mit.edu), Massachusetts Institute of Technology. Downloaded on [DD Month YYYY]. 4. Probl em 4 I nthel i nkages howni nFi gur e4be l ow,thedi s kBands l i de rCe achhavea mas s m. Thel i nkse achhavea l e ngthlandar eofne gl i gi bl emas s . Thes pr i nghasa s ti f f ne s skanduns tr e tche dl e ngth2l . Thes l i de ri spus he ddownbya s mal l di s tances uchthat thes pr i ngi scompr e s s e d,andthes y s te mi sr e l e as e d. Notethat gr avi tyacts . Al s onoti cethat poi nt Ai spi nne ds oi t doe snot move . a. Fi ndthee quati onofmoti on. b. Fi ndthee qui l i br i a ofthes y s te m. c. Li ne ar i z e the e quati on ofmoti on about the e qui l i br i um poi ntsand e xami nethes tabi l i tyofthee qui l i br i a. g Fi gure4 Cite as: Sanjay Sarma, Nicholas Makris, Yahya Modarres-Sadeghi, and Peter So, course materials for 2.003J/1.053J Dynamics and Control I, Fall 2007. MIT OpenCourseWare (http://ocw.mit.edu), Massachusetts Institute of Technology. Downloaded on [DD Month YYYY].