Fig. 1. Scanning principle diagram

Fig. 2. Schematic diagram of relative position between shaft guide and laser scanner

Fig. 3. Schematic diagram of left and right correction

Fig. 4. Algorithm flow diagram

Fig. 5. Model diagram of shaft guide

Fig. 6. Three-time misalignment measurement value diagram of gap Ⅰ and gap Ⅱ

Fig. 7. Field experiment map

Fig. 8. The partial outline of the shaft guide before and after the edge line is clarified

Fig. 9. Overall outline of the full length of the shaft guide

Fig. 10. Comparison of measured values and reference values

Fig. 11. The overall outline of the shaft guide after using the adaptive threshold judgement algorithm