Question

Can someone help me with MatLab?

Answer 1

The displacement of the slider of the slider-crank mechanism is given by, \[s=a*\cos(\phi)+\sqrt{b^2-(a*\sin(\phi)-e^2)}\]Plot the displacement as a function of the angle phi (in degrees)when a=1, b=1.5, e=0.5, and\[0\le \phi \le 360\]

Answer 2

that is, use
[ plot ( phi , s ) ]

Answer 3

so far this is what i did

Answer 4

syms phi
a=1
b=1.5
e=0.5
phi=linspace(0,360)
s=((a*cos(phi)+sqrt(b^2-(a*sin(phi)+e^2)))

Answer 5

thisis what the slider-crank mechanism looks like.

Answer 6

it tells me that i have a conflict with the variables. i guess it has to do with the s=f(phi) when i plug it into plot(phi,s) in the end. but i don't know how to fix it.

Answer 7

Trigonometric functions in matlab (sin, cos,...) assumed the angles in radians, so to convert to radians multiply phi by pi and divided by 180

Answer 8

ok so i did this now:

syms phi U
a=1
b=1.5
c=0.3
phi=linspace(0, 2*pi)
U=(Phi*pi)/180
s=(a*cos(U)+sqrt(b^2-(a*sin(U)-e)^2))
plot(U,s)

it gives me this error message:

error using ^
inputs must be scalar and a square matrix. to compute otherwise POWER, use POWER (.^) instead.
Error in homework1 (line 22) s=(a*cos(U)+sqrt(b^2-(a*sin(U)-e)^2))

Answer 9

phi and U will be vectors
when you do cos(U), you get back a vector (a cosine value for each number in U)
you can multiply the vector by a constant, matlab will multiply each number in the vector by the constant.
however, you also have -e^2 and b^2 that you are adding.
matlab does not know how to do that.
you will have to make a vector of the same size as U, doing (for example)
b_vec= b^2*ones(sizeof(U))
do the same for e^2
or combine them: be_vec= (b^2+e^2)*ones(sizeof(U))