A system assists a user to traverse a structure. A safety device includes a sensor assembly to detect positions of a user along a travel path for a structure, wherein the travel path includes a plurality of attachment points to secure the user to the structure via one or more lines, a motion assembly to move the safety device along the travel path based on the detected positions of the user, wherein the motion assembly maintains a threshold distance from the user, and a coupling mechanism to couple the one or more lines to one or more of the attachment points encountered along the travel path. Embodiments of the present invention further include a method and program product for assisting a user to traverse a structure in substantially the same manner described above.