A system for determining relative position information comprising: a plurality of positioning devices for determining relative position data within a three-dimensional space, which is a manufacturing space used for manufacture and assembly of an object such as an aircraft, each positioning device having a line of sight and being mounted to a structure within the three-dimensional space and being configured to determine a respective position of each other positioning device, relative to itself, that is within its line of sight so that geometry of the system is mathematically over-constrained, which structure is an exterior wall, a ceiling or a floor of the three-dimensional space, and wherein the relative position data determined via each positioning device comprises relative positions of each of the positioning devices with respect to the other positioning devices within its line of sight; a plurality of imaging devices for obtaining image data of an object within the three-dimensional space; and a computing device configured to correlate the relative position data determined via the plurality of positioning devices and the image data obtained via the plurality of imaging devices to thereby determine relative position information corresponding to the object within the three-dimensional space, wherein, based on a movement of a given positioning device of the plurality of positioning devices caused by environmental factors such as temperature, weather and tidal effects which cause a shape of the three-dimensional space to change, the computing device is configured to determine, via each other positioning device within the line of sight of the given positioning device, updated relative position data for the given positioning device with respect to the other positioning devices, and wherein the computing device is further configured to correlate the updated relative position data and the image data obtained via the plurality of imaging devices to thereby determine updated relative position information corresponding to the object within the three-dimensional space, wherein the system is configured to account for the movement of the given positioning device by over-determining the relative position of each of the positioning devices without an absolute reference point on which to base the determination. a plurality of positioning devices for determining relative position data within a three-dimensional space, which is a manufacturing space used for manufacture and assembly of an object such as an aircraft, each positioning device having a line of sight and being mounted to a structure within the three-dimensional space and being configured to determine a respective position of each other positioning device, relative to itself, that is within its line of sight so that geometry of the system is mathematically over-constrained, which structure is an exterior wall, a ceiling or a floor of the three-dimensional space, and wherein the relative position data determined via each positioning device comprises relative positions of each of the positioning devices with respect to the other positioning devices within its line of sight; a plurality of imaging devices for obtaining image data of an object within the three-dimensional space; and a computing device configured to correlate the relative position data determined via the plurality of positioning devices and the image data obtained via the plurality of imaging devices to thereby determine relative position information corresponding to the object within the three-dimensional space, wherein, based on a movement of a given positioning device of the plurality of positioning devices caused by environmental factors such as temperature, weather and tidal effects which cause a shape of the three-dimensional space to change, the computing device is configured to determine, via each other positioning device within the line of sight of the given positioning device, updated relative position data for the given positioning device with respect to the other positioning devices, and wherein the computing device is further configured to correlate the updated relative position data and the image data obtained via the plurality of imaging devices to thereby determine updated relative position information corresponding to the object within the three-dimensional space, wherein the system is configured to account for the movement of the given positioning device by over-determining the relative position of each of the positioning devices without an absolute reference point on which to base the determination.