Measure weight of an object that is on torque arm?

[tlhsglm]

Hi fellows,

How can i get measure of the object that i dont know distance of object's center of gravity from sensor?Auxiliary picture is below. object 1 and object 2 is not putting on beam at same time, drawed just to show how far that can be;



I have 1 idea like picture below but it's not good because of combining 2 load cells not recommended and gives x2 x2,5 more bad accurety.
Thats mathematic is ; ( thick ones are known)
load cell1 value=(object's weight) x distance1
load cell2 value=(object's weight) x distance2
distance2 - distance of load cells from each other = distance1
Weights can be found from these equations

[Kleinstein]

The solution is probably the way to go.  Besides the 2 sensor solution, there may also be a mechanical system with leavers to separte the downward force from the torque.

[tlhsglm]

The solution is probably the way to go.  Besides the 2 sensor solution, there may also be a mechanical system with leavers to separte the downward force from the torque.

Can you please give me a sample or a trace to google it?

[Ian.M]

You'd need to resolve the forces into horizontal and vertical components.  A parallelogram linkage, with ball or roller bearing pivots, with its fixed bar vertical, and the beam attached to its moving vertical bar would do the job.  Rest the moving vertical bar on a load cell.

[EmmanuelFaure]

Thats mathematic is ; ( thick ones are known)
load cell1 value=(object's weight) x distance1
load cell2 value=(object's weight) x distance2
distance2 - distance of load cells from each other = distance1

Your 2 load cell mechanism is the way to go. But your equations are not correct. Even dimensionnaly : "load cell1 value[/b]=(object's weight) x distance1". The left member of the equation is a force, and the right a force * a distance. The multiplicative term have to be adimensional, you have to have a force on both sides.

Correct equations from the lever theory : With G = Object center of gravity. L1 = Load cell 1 (left). L2 = Load cell 2 (right). Positive sign = Force to the top.
Force on the left load cell = Object weight * GL2 / L1L2
Force on the right load cell = - Object weight * GL1 / L1L2

And to check, F load cell left + F load cell right = Object weight. Which is correct.