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# Load Cells


**Purpose:** The purpose of this page is to provide a place to store our load cell designs.

###**Tensile Load Cell**###

For tensile testing, our S-Beam load cell can measure up to 5000 lbf. This tension load is applied by pulling on the attached eyebolts.

[[!img S_cell1.jpg size="320x250"]]
[[!img S_cell2.jpg size="320x250"]]

The tensile load cell is machined specifically to create a shear strain on part of the load cell. The shear strain is measured using a 45 degree shear strain gage. With a load of 5000 lbs, the load cell will stretch by 0.014". Given the 3.5" cell length, this maps to 0.014/3.5=0.004 inch/inch, or 4000 microstrain. Given the 30,000 max microstrain of the sensor, we are well under the max operating range of the strain gauge.

###**Bending Load Cell**###

Our low force aluminum bending beam load cell can very accurately measure +- 8 lbf.

[[!img beam_cell1.jpg size="320x250"]]
[[!img beam_cell2.jpg size="320x250"]]

The strain gages used on the bending load cell are also 45 degree shear strain sensors. To measure the bending load applied to the cell, the strain gage is mounted on a 45 degree angle. A tensile force (load) is measured by clamping one end of the beam to a rigid surface; and then applying a tensile force to the other end of the beam using a link and cord.

###**Thrust (Bending) Load Cell**###

Our rocket motor thrust sensor can measure up to 1200 lbf. Like the bending load cell, forces are measured by measuring the strain on a beam. The difference is that the thrust sensor beam compensates for temperature and unwanted side loads by measuring strain on both sides of the beam.