An inspection robot is provided to traverse the interior of a pipeline for the purpose of checking the coating at the interior surface of the pipeline at the weld seams. The robot is designed to determine the thickness of the coatings and to provide a visual and recordable reading thereof. The robot is provided with a holiday detector in the form of a conductive brush mounted on a rotatable hub and adapted to sweep against the weld seam so as to locate any voids in the coating by means of electrical conductance, thus causing a holiday marker to activate and mark the pipeline interior surface so that the site can be revisited for repair. The robot is further provided with a mil gauge probe mounted on a slidable plunger attached to the rotatable hub for measuring coating thickness on the weld seam and for providing data via a digital mil gauge readout; the conductive brush, the slidable plunger for mil gauge probe, the digital mil gauge readout, and the forward portion of the robot being all provided with cameras which simultaneously record the movements and data encountered by the inspection robot to provide real-time feedback to a remote operator.