This interface force transducer was used to measure basal normal force at the channel bottom of the large rotating debris flow flume.
"We measured basal normal force with a steel load plate attached at the plate’s center to ashear-compensating Interface Force Model SWP10-5K-B000 Precision Force Transducer. The transducer has a maximum load of 2273 kg (5000 lb) and a resting noise of roughly 0.2 kg. The plate and load cell assembly are attached to the drum and further stabilized by two large, steel rectangular tube bars on the outside of the drum. To water-seal the plate, a neoprene gasket was attached on the back side of the plate-bounding gap. The gap was filled with silicone to prevent lodging of sediment, which would restrict plate movement. Power and data were transferred to and from the plate through a slip ring on the hub of the wheel. Measurements were made using an analog-to-digital board at 200 kHz, then averaged to 1 ms, effectively sampling at 1 kHz. Load cell measurements were synchronized with laser scanner measurements through a trigger from a rotary encoder mounted in the hub of the wheel. Additional information about the force plate is included in the supporting information."
