Abstract: An apparatus and method for monitoring the condition at or near the surface of objects is disclosed. The apparatus is a vehicle which includes a housing which is supported and translated across the object surface by three wheels. The front or first wheel is associated with an encoder and sensor which magnetically determines the physical condition of the object. The apparatus includes a starter block which includes a series of metallic wires embedded at certain depths and locations within the starter block. The vehicle passes over the starter block prior to passing over the object in order that the vehicle be recalibrated by the starter block prior to observing the physical condition of the object.