Load Cell Design

Here are some examples of load cells I've designed. On the left is a knee pivot box that has been re-engineered to have a small cantilevered section that is instrumented with foil strain gauges in a full bridge to measure the bending moment in that beam which corresponds to the torque the actuator is outputting. In the small, plastic cover/pinch guard, we installed a small signal conditioning board that allowed us to calibrate the sensor before installing it into the unit. On the right there is another load cell design that measures the axial force in a ball screw. The lower right side of the part attaches to a linear rail to take any off-axis loads. You can see the small flexural parts just above the large round bosses. These allowed for misalignment of the ballscrew mounting. Again, a small signal conditioning board was installed to allow for calibration outside of the unit.