obtaining force/displacement values?
obtaining force/displacement values?
(OP)
Hi all,
im currently involved in the redesign of a major component at our plant and am required to gather data on the forces acting on the machinery.
the piece of equiptment is a roller which is pneumatically powered to rise and lift a sheet and then fall via quick exhaust acting as a quick outlet for the pressure.
im aiming to calculate the bending moment and shear stress acting on the clevis brackets holding the roll in place.
any ideas on how i can obtain some acceleration, force values using instrumentation?
regards
im currently involved in the redesign of a major component at our plant and am required to gather data on the forces acting on the machinery.
the piece of equiptment is a roller which is pneumatically powered to rise and lift a sheet and then fall via quick exhaust acting as a quick outlet for the pressure.
im aiming to calculate the bending moment and shear stress acting on the clevis brackets holding the roll in place.
any ideas on how i can obtain some acceleration, force values using instrumentation?
regards





RE: obtaining force/displacement values?
RE: obtaining force/displacement values?
If you want to get displacement directly, then you could attach an LVDT to the base/cylinder and roller/piston.
If you are going to use an Accelerometer, make sure its a DC Accelerometer - then you can integrate to get velocity and displacement.
Finally, how about monitoring the air pressure throughout the cycle - a poor second to the load cell.
For all this you should acquire data at something like a kilohertz - as a guess, not knowing your system in any detail.
RE: obtaining force/displacement values?
I agree to MintJulep and solider.
RE: obtaining force/displacement values?
If not, is there a particular part of the cycle you are concerned with?
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RE: obtaining force/displacement values?
what data will the accelorometer actually display?
RE: obtaining force/displacement values?
RE: obtaining force/displacement values?
For the block, the mass (m) is the weight divided by the acceleration due to gravity (g).
For the spring F = kx.
And by Newton's 2nd F = ma . . . so ma = kx, and a = kx/m.
Mount the potentiometer on the bracket, the spring on the potentiometer shaft and the block on top of the spring.
Each time the roller falls, the potentiometer will record a max displacement (x).
From this you'll get acceleration without spending a fortune for equipment that won't be used long term.
RE: obtaining force/displacement values?
RE: obtaining force/displacement values?
Cheers
Greg Locock
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