Abstract: According to the verification and calibration requirements of tide gauge, a tide gauge verification device based on image recognition is proposed. The device establishes the internal correlation between tidal water level and image recognition, and is composed of water tower system, water supply and drainage system, servo system, central control system and software system. the device realizes the image recognition of tidal water level changes under closed-loop control, accurately detect the reading value of transparent pipe water-base line and indium steel ruler tick mark, and can simulate the semi-diurnal tide and diurnal tide variation rules. It has manual, automatic and mobile APP remote control function. Finally, this thesis analyzes and evaluates the measurement characteristics of the device. The results show that the device can meet the verification and calibration requirements of float-type tide gauge, acoustic tide gauge and pressure tide gauge, and has a good.

Key words: Metrology, Tide gauge, Verification device, Image recognitiong, Closed-loop control