dynamic analysis
dynamic analysis
(OP)
I have been away from static and dynamic analysis too long. I would like to know how to determine the coefficient of friction value for the following problem. I have a box 24" tall x 20" deep and 14" wide traveling on a conveyor at 18"/sec. IF a bar is placed at the top of the box as to knock it down. What coefficient of friction belt do I need to prevent the box from slipping on the belt?





RE: dynamic analysis
Find the center of gravity and the weight of the package. This gives you the normal force N. Horizontal force due to friction f= mu*N.
The horizontal force due to bar? Set = to f
Tipping force: Sum of the moments.
M(gravity) = Weight* (tipping point to C.G.) If package is uniform density
Mg = 7 * W
M(tipping) = f*Height of Bar
Make mu big enough so that the box tips.
Don Leffingwell
dleffingwell@snet.net
(My last class in Statics was 30 years ago.)
I don't think you need to go into a dynamics analysis.
RE: dynamic analysis
the question posed by u is quite straight.
there r three forces,
1-friction force (at base of box)=nu*weight of box;
2-force due to acceleration of box(at C.G. of box)=mass of box *acceleration of motion;
3-force of bar ment for topling the box;
now if u balance these three moments u will get the value of force just sufficient to topple the box.