The present apparatus is configured to carry an instrument or probe and optionally deploy it against a surface, such as a metal pipeline or storage tank. The apparatus can include a sensor probe for inspecting the integrity of the surface and a first linkage that is operatively coupled to the sensor probe and configured to move the sensor probe according to a first path (in a first direction/first degree of freedom). An actuator can be operatively connected to the first linkage for moving the first linkage so as to move the sensor probe along the first path. A second linkage is operatively connected to the sensor probe and configured to passively move the sensor probe according to a second degree of freedom to cause the sensor probe to become normal to the surface when at least a portion of the apparatus contacts the surface.