Abstract: This paper focuses on the detection of typical geometric parameters of a flow deflector device and establishes a mathematical model for the proposed detection method. The detection algorithms for geometric parameters such as coaxiality, blade installation angle, and blade reverse angle are theoretically derived. Based on these algorithms, complex geometric parameter measurements of the flow deflector device can be achieved using simple linear displacement sensors.A validation platform is then constructed to verify the proposed algorithm. The verification results show that the measured values obtained from the platform are highly consistent with the true values, demonstrating good repeatability and low bias of the algorithm. Through this method, automated detection of geometric parameters for such flow deflector devices can be realized, thereby meeting the requirements for inspection process automation in production line construction.