Physics Constraint Force on Moving Object

Hi

I’m working on a project where I have a Crane that can pick up items. The hook of the crane goes through a loop and physically lifts the object up.

The physics constraint is constraining the Crane Hook to the Crane Body and adjusts the height of the hook by increasing Z limit of the constraint.

I want to calculate the Lift Mass while lifting to get the exact amount of added mass for the crane.
This is my approach:


Dividing the Z Force by 1000 returns the total Mass, in this instance the Hook is 20,000Kg ( because it has to lift at least 20,000Kg Objects using physics ) and I’m subtracting this amount from the Z Force, which returns the remaining mass, corresponding with the set mass of the object I picked up.


Problem

The problem I’m having, is as I’m moving the Hook the Z Force values changes dramatically.
After division ( / 1000 ) when moving the Hook downward it produces a result varying from 20,000 up to around 100,000 with the Hook empty ( No objects lifted, but same result happens with objects lifted also) .

Expected Value is ( 20,000 only ) As I’m simply increasing the limit of the Constraint, no additional force should be added when lowering the hook, as its only increasing the allowed distance the hook can fall. So the weight of the hook should be the only returned value, but the returned Z Force is much greater than the mass of the object.


Why not just get the mass of the object?

*Because I want the system to be as systematic as possible, Any weight you pickup, regardless of how many parented physics children it has needs to return the weight value. This is the workaround plan if this is unsolvable. But I really want a clean way of calculating added mass to a constraint…


If you have any ideas of how to do this differently or what might be wrong causing this issue, I’d appreciate any help!

Thank You!