MMAE 350
D. Rempfer
Problem Set III
Page 1 of 2
Due Date: September 27, 2006
1.
We
want
to
write
a
M
ATLAB
function
crankangle
that
can
give
us
the
crank
an
gle
α
of the crank drive shown on the right, given
the vertical position
s
of the piston.
The function should take as its input parameters
the radius
r
of the crank, the length
l
of the con
necting rod, and the piston position
s
measured
as shown in the figure.
Thus the function will
roughly have the following structure:
function alpha=crankangle(r,l,s)
...
alpha=...;
a.
What is the equation describing the piston
position
s
as a function of
r
,
l
, and
α
?
b.
If the ratio of connecting rod length over
crank radius becomes very large,
l/r
1,
then the above equation can be approximated
by a much simpler relation.
What is the
equation for the approximate piston position
in this case?
α
c.
Write a M
ATLAB
function,
spiston(r,l,alpha)
that takes
r
,
l
, and
α
as its input, and
provides the piston position
s
as the output, plus a function
dspiston(r,l,alpha)
which
provides the derivative of the piston position with respect to the crank angle.
d.
With these preparations out of the way, you can now code the M
ATLAB
function
crankangle
.
This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
This is the end of the preview.
Sign up
to
access the rest of the document.
 Spring '05
 rempher
 Connecting rod, Crankshaft, Root of a function, D. Rempfer

Click to edit the document details