A Portable Tillage Profiler for Measuring Subsoiling Disruption

A portable tillage profiler (PTP) was constructed using a laser distance sensor, a linear actuator, a portable PC, and a lightweight aluminum frame that can quickly and accurately measure aboveground and belowground soil disruption caused by tillage. A laboratory experiment was conducted that determined that soil color did not detrimentally affect the PTP, with expected vertical errors of 2.3 mm and horizontal errors of 0.6 mm being found. However, when pure white and black objects were examined, the errors increased to 4.2 mm vertically and 11 mm horizontally. This maximum error was established when attempting to measure the height and width of a wedge, which had a sharpened edge pointing vertically upward. The PTP was used in the National Soil Dynamics Laboratory soil bins to measure both aboveground and belowground soil disruption caused by two subsoiler shanks. The PTP gave results that enabled differences between the aboveground disruptions caused by each subsoiler to be statistically established.