EGR-352

Assignment #4

Eric J. Schmitt

PROBLEM

For the example in the notes:

1. Derive functions for the curves.

2. Determine actual values for b0, b2, b3.

3. Create an AUTOCAD drawing of the cam.

4. Create a Working Model of the cam.

SOLUTION:

I derived the equations using the method from lecture, see Mathcad Worksheet. After deriving the equations, I exported the graphs of each piece of the function to a CAD package called Vellum. Once I had each plot in Vellum, I traced over each curve, then connected them all together. After the plot drawing was created, I exported it to Working Model as a DXF file and working model created the image of the time function. See Working Model drawing of the displacement vs. time function of the cam follower.

Using the equation f(X)=A*X^3+B*X^2+C*X+D and solving for the initial and final conditions of each region of the function the values of b0, b2, b3 as well as the coeffecients of each region were found.

b0 = .0525 seconds which converts to 47.25 deg of the cam.

b2 = .105 seconds which converts to 94.5 deg of the cam.

b3 = .0925 seconds which converts to 83.25 deg of the cam.