Have a question sort of related to question at (What calculation to find how much force before tipping over?) but with slight modifications.
Trying to weld some tubing together and onto a heavier base to hold a window open temporarily so a window air conditioning unit can be installed/removed easier. The window would place downward pressure as indicated by the arrow. Which design is most resistant to tipping leftward (and out the window) or are all the same since the length of the holding bar changes with the base placement?
Choice is Left, Middle, or Right.
Thanks in advance!
$\begingroup$
$\endgroup$
2
-
$\begingroup$ they all have the same tipping condition unless we consider the material bending. In which case all of the structures are non-optimal left being least problematic. Nothing can be said about the design as such without knowing forces and structure specifics. Triangles, triangles, triangles. $\endgroup$– joojaaCommented Aug 19, 2023 at 21:24
-
$\begingroup$ Almost the same - negligible differences if not deforming and force to tip is large. There's also mass of the blue thing itself to consider; that's where differences lie. $\endgroup$– AbelCommented Sep 18, 2023 at 3:44
Add a comment
|
1 Answer
$\begingroup$
$\endgroup$
By eyeballing The amount the top tubings cantilever from the base footprint are all the same. We consider the tubing much lighter than the Base.
let's call the length the cantilever top tubing is offset from the base $E$ and the width of the base $W$ and its mass $ m$ and its left end $A$, right end $B$.
The force this rig can support before it topples, F is
$$\Sigma M_{A}=0,\quad F=\frac{m*W}{2E}$$
The heavier and wider the base the more force is needed to topple it. We should add a safety factor too. As shown in your figure all three are the same!
