Taylor Turner
Member
This is 99% a structural design flaw, but most people here have the capacity to manage this.
First, some R&D background. I have a strain gauge on the throat of a C frame press and the actuator has a platen face that meets a mobile load cell and is sitting on a stationary platen.
I can calibrate the strain gauge to the load cell, when it is centered. But when the load cell is positioned to the front or back, the strain increases or decreases, which is not accurate to the actual force.
Additional inquiry, do load cells, with direct force measurement, share this same calibration dissonance when the force is not in the same as the calibration location?
Without exception, the stain gauge will be moved to the actuator rod to measure force more directly. I have doubts that this will be good enough because of my last thought that a load cell itself will show this flaw.
I have thought to include two strain gauges on the actuator rod, 90 degrees out of phase, and sum a certain expression when a constant torque or pressure is generated on the newly installed tool as a calibration cycle.
Where 1 gauge is x, the other y…
Force offset = ycalibrated+( ycalibrated-ymeasured)+xcalibrated+( xcalibrated-xmeasured)
Does anyone have other thoughts?
First, some R&D background. I have a strain gauge on the throat of a C frame press and the actuator has a platen face that meets a mobile load cell and is sitting on a stationary platen.
I can calibrate the strain gauge to the load cell, when it is centered. But when the load cell is positioned to the front or back, the strain increases or decreases, which is not accurate to the actual force.
Additional inquiry, do load cells, with direct force measurement, share this same calibration dissonance when the force is not in the same as the calibration location?
Without exception, the stain gauge will be moved to the actuator rod to measure force more directly. I have doubts that this will be good enough because of my last thought that a load cell itself will show this flaw.
I have thought to include two strain gauges on the actuator rod, 90 degrees out of phase, and sum a certain expression when a constant torque or pressure is generated on the newly installed tool as a calibration cycle.
Where 1 gauge is x, the other y…
Force offset = ycalibrated+( ycalibrated-ymeasured)+xcalibrated+( xcalibrated-xmeasured)
Does anyone have other thoughts?