Aiming at the challenge of establishing a large-distance straight-line datum in aviation manufacturing

assembly

and testing sites

a method for constructing a large-distance straight-line datum based on laser collimation and multi-sensor fusion was proposed. The measurement and compensation optical paths were designed and the photoelectric detection device was developed

using the collimated laser beam as the straight-line datum. The precise solution of the target pose was achieved by detecting the spot coordinates of the collimated laser beam using position sensitive detector (PSD) on the device

and combining them with the data from the tilt sensor. Experimental results indicated that the proposed method can accurately measure pose variations encompassing two translational and three rotational degrees of freedom (5 DOF in total). Within a 5 m range

the positional measurement error was less than 6 μm and angular measurement error was less than 0.003°

the effective operational distance was up to 50 m

fulfilling the accuracy requirements for establishing a large-distance straight-line datum.