wondering if someone could do a quick check and see if I did anything wrong.

You can find the diagram at the link below

formatting link

Here are the constraints.

Points 1, 2, 3, and 4 are pivot points.

Point 1 is fixed in space.

Points 2 and 4 are free to move in the plane.

Point 3 can only move up and down (closer or further from point 1).

The links connecting points 1 & 2, 2 & 3, 3 & 4 and 4 & 1 are all the

same length (L).

A force (F) is applied at point 3.

What I want to know is the torque about point 1 applied by each link as

the angle (a) varies from 5 to 85 degrees.

Step 1 find the force in the links from 2 to 3 and 3 to 4 which should

be the same.

Fl = .5 * F/cos(a)

The .5 is because each of the two links (2 to 3 and 3 to 4) will have

half of the force F.

Step 2 find the perpendicular distance (Torque Arm: TA):from point 1 to

the line through points 2 and 3.

TA = L

*** cos(x)**

x is 90 - (2 *a)

x is 90 - (2 *

Step 3 multiply Force and arm length

Torque = FL * TA

So the full formula would be

Torque = .5 x F/cos(a)

*** L ***cos(90 - (2 * a))

Thanks for the help.