Homework 9, due April 7, 2010.

[goodwine]

From the course text, 9.15, 9.16, 9.17, 9.26 and 9.30.

[cplagema]

For 9.17, since the transfer function is for Xdot/F instead of X/F, does "proportional control" still refer to F=Kp*(Xdot_desired - Xdot), or now is it Kp*(X_desired - Xdot), which is really derivative control for X/F?
Thanks!

[goodwine]

For 9.17, since the transfer function is for Xdot/F instead of X/F, does "proportional control" still refer to F=Kp*(Xdot_desired - Xdot), or now is it Kp*(X_desired - Xdot), which is really derivative control for X/F?
Thanks!

It's the former, F=Kp*(Xdot_desired - Xdot).

[AL089]

Professor, just a heads up but Figures 9.98 and 9.99 are pretty faded and don't show all the branches and asymptotes of the root locus, at least in my copy. It's not hard to get what the real plots look like, but it might be confusing if somebody doesn't realize that parts are missing. Again, it might only be my book.

[lawnoy]

Professor,

Shouldn't the expression for rise time in 9.26 be tr=1.8/wd? All the expressions of rise time in the book are in terms of damped frequency.

[goodwine]

Professor,

Shouldn't the expression for rise time in 9.26 be tr=1.8/wd? All the expressions of rise time in the book are in terms of damped frequency.

No, it's the natural frequency. That's why I specified it in the problem.