The UC Davis Soil compaction sensor (UCD-SCPS) is designed to quantify soil mechanical strength in a continuous way. This sensor consists of an instrumented shank, a data acquisition system and a DGPS receiver. The UCD-SCPS sensor is attached to a frame that is mounted on the 3-point hitch of a farm tractor and pulled through the field engaging the soil in a way similar to a commercial ripper shank. This sensor can provide data related to the soil profile up to a depth of 460 mm using a set of five force transducers. The instrumented blade has a thickness of 29 mm. Previous reports on the field performance of this sensor have shown that the output of this system correlated with the state of the soil as determined by soil density and moisture content. Moreover, the sensor output showed high correlation with cone index (CI), which is a well recognized standard used in soil-plant studies to characterize soil compaction, when the location of the force transducers within the soil profile was properly accounted.