Homework2

http://docs.google.com/viewer?a=v&pid=sites&srcid=ZW5nLnVjc2QuZWR1fG1hZTE1NmF8Z3g6NjExZDgwNmU1NGJhYjk1ZQ

Link to PDF: HW2 PDF

Office Hours Correction:

Max power of a motor (number 1g) is given by:

TBD Values:

L1 = 15cm

L2 = 5cm

M_disk = 230g

I_disk= 5.26e-4 Kgm^2

Disk 2b is the same as Disk 1

p1 = 10t XL pulley

p2 = 42t XL pulley

Part 1 Clarifications:

c.i) method 2 alludes to but does not specifically give the formula. Where I and \omega are the no load current and speed.

f.i) Use a time constant of .005s. The suggested constant will bias the data. The "Turn in" section also asks you to use a curve fit function in matlab, which could be suggesting the fit() function?

Part 2 Clarifications:

Assumptions:

    • pulleys and shafts are massless

    • Pulleys an disk in 2b are evenly spaced, see below for clarified diagram

    • the angle of the timing belt is neglible

    • the timing belts have no pre-tension

    • there is no viscous friction

2a) Instructions:

    1. Draw a FBD of the single shaft setup.

    2. List equations of motion

    3. Model the system in matlab with a disk and without (only motor inertia)

    4. for both, plot: displacement (radians) and filtered velocity (rad/s) vs time (on the same plot). Filtered????? This is a numerical simulation, there is nothing to filter!

    5. for both, plot: motor torque (Nm) and Power (W) vs time (on the same plot).

2b) Instructions:

    1. You do not need a FBD. You can derive the equivalent inertia and friction using energy methods.

    2. Model the system in matlab with a disk and without (only motor inertia)

    3. for both, plot: displacement (radians) and velocity (rad/s) vs time (on the same plot).

    4. for both, plot: motor torque (Nm) and Power (W) vs time

2b: Clarified Diagram: