Patent ID: 8220339

Claim:
A mobile turf instrument apparatus, which comprises: (a) a frame movable over the ground, wherein the frame has an arm that is movably driven relative to the frame as the frame moves over the ground to cyclically move a portion of the arm towards and away from the ground as the frame moves over the ground; (b) a probe assembly carried on the portion of the arm that moves towards and away from the ground, the probe assembly having at least one ground engaging probe, wherein the probe assembly comprises a first part and a second part that is pivoted on the first part such that the first and second parts are able to move relative to one another when the probe(s) are inserted into the ground by pivoting or rocking of the second part of the probe assembly on the first part of the probe assembly; (c) a soil moisture sensor carried on the probe assembly for measuring soil moisture when the probe(s) are inserted into the ground; and (d) a load cell carried on the probe assembly and responsive to the amount of relative movement of the two parts of the probe assembly when the probe(s) are inserted into the ground to measure soil compaction.