A robotic vehicle for traversing surfaces comprises a chassis having a plurality of wheels mounted thereto. Two magnetic drive wheels are spaced apart in a lateral direction and rotate about a rotational axis while a stabilizing wheel is provided in front of or behind the two drive wheels. The drive wheels are configured to be driven independently, thereby driving and steering the vehicle along the surface. The vehicle also includes a sensor probe assembly that is supported by the chassis and configured to take measurements of the surface being traversed. In accordance with a salient aspect, the vehicle includes a probe normalization mechanism that is configured to determine the surface curvature and adjust the orientation of the probe transducer as a function of the curvature of the surface, thereby maintaining the probe at the preferred inspection angle irrespective of changes in the surface curvature with vehicle movement.