1.053/2.003  Dynamics and Control I

Hello all,

The solutions to the final exam have now been posted on the class website. The grades will be forwarded to the undergrad office within a day and they may or may not show up on websis before christmas depending on when MIT closes for holidays.

The graded final exams can be picked up from Mani (3-347A) by setting up a time with him via e-mail.

Happy holidays!  

The final exam is on Thursday, Dec 18th from 9:00am - 12:00noon in duPont.

(1) Three pieces of two-sided hand-written notes are allowed.

(2) The exam is 3 hours, five questions, with at least two on vibrations.

(3) No calculators

Good luck with the preparations (there is now an extra sample exam posted),

Mani.

Dear all,

There will be a 2hr review session on Dec 17th, Wednesday, a day before the final exam. It is between 5pm and 7pm  at 3-270. As before, I will do the first one hour (general concepts), and Danny will do the second (sample problems).

There will be extra office hours next week. I will update the following as soon as the times and locations get fixed.

Prof. Peacock - 3-270 - Wednesday - 1pm-2pm

Prof. Rosakis - 3-352 - Tuesday - 11am-12noon

Prof. Makris - 5-212 - Tuesday - 4:30pm - 5:30pm

Mani - 1-134 - Tuesday - 3pm-5pm

Danny -1-150 Wednesday - 2pm-4pm

All pset solutions are now available to be picked up from me at 3-347A. It seems like not many students picked up the solutions after lecture yesterday.

Please keep checking this space now and then, I will not e-mail the announcement everytime I edit it.

Best,

Mani. 

To clarify the answers to a few good questions in class

(1)  It is necessary that for the initial coupling assumption of -1/2*epsilon*x and -1/2*epsilon*theta the two are of the same sign. For the way we set it up this ensures that a displacement +x causes a rotation -theta, and that a rotation -theta will cause a displacement +x. We could have chosen both coupling terms to be positive, which would correspond to a spring coiled in the opposite sense. The important thing is that they both
have the same sign.

(2) It is not necessary for the epsilon in the force equation and the epsilon in the torque equation to be the same value. We can call them epsilon_1 and epsilon_2 with different dimensions appropriate to a force equation and a torque equation . They only play an important role when
multiplied together to calculate the natural frequencies, at which point we could define epsilon_1*epsilon_2=epsilon^2 and proceeded from there.

(3) It is okay that the mode shapes c1 and c2 are related by a dimensional constant sqrt(m/I). This arises naturally because one state variable is a displacement and the other is a rotation.

Prof. Peacock.

There will be extra office hours tomorrow for pset 9. The details are below:

Room - 3-270

Time - 5pm-7pm

Danny will do 5pm-6pm, and I will do 6pm-7pm.

The average in quiz 2 was 20.7 and the standard deviation 4.3.

Best,

Mani.