A pathway measurement system hereof includes a rigid frame and a mobility system attached to the frame. The mobility system includes at least one movable element which is adapted to contact a surface of a pathway via which the frame may be moved relative to the pathway. The pathway measurement system further includes at least one sensor adapted to measure at least one characteristic of a pathway. The pathway measurement system has a first mode of operation in which the mobility system moves the frame along the pathway to move the at least one sensor relative to the pathway. The at least one sensor is connected to the pathway system such that a distance between the at least one sensor and an axis of rotation of one of the moveable elements remains constant in the first mode of operation. In general, the at least one sensor is isolated from any compliance or suspension system.