Bolt axial force measurement method, device, apparatus, and readable storage medium

A bolt axial force measurement device, comprising:

• an image capturing unit for capturing an image of a bridge bolt by a movable imaging device;
• an identification processing unit for identifying an outer edge of a nut, a centroid of the nut, and a circular position of a laser spot at a center of the bridge bolt in the captured image of the bridge bolt;
• an image obtaining unit for projecting a calibration laser spot onto a bolt plate and obtaining a current frame as a bolt-detection image when the outer edge of the nut, the centroid of the nut, and the circular position of the laser spot at the center of the bridge bolt in the captured image of the bridge bolt meet preset conditions;
• a dimensional calibration unit for performing dimensional calibration on the bolt-detection image based on a size of the calibration laser spot in the bolt-detection image and determining a displacement of each of the pre-calibrated feature points on the bridge bolt in the bolt-detection image;
• and
• an axial force calculation unit for calculating a bolt axial force value based on the displacement of each of the pre-calibrated feature points on the bridge bolt in the bolt-detection image;
• wherein the dimensional calibration on the bolt-detection image based on a size of the calibration laser spot in the bolt-detection image and determination of a displacement of each of the pre-calibrated feature points on the bridge bolt in the bolt-detection image are performed by:
• determining an actual size of the calibration laser spot based on the size of the calibration laser spot in the bolt-detection image and a corresponding dimensional calibration curve;
• performing dimensional calibration in the bolt-detection image based on the actual size of the calibration laser spot;
• reading a position of each of the pre-calibrated feature points on the bridge bolt in the bolt-detection image dimensionally calibrated;
• and
• calculating the displacement of each of the pre-calibrated feature points on the bridge bolt in the bolt-detection image by establishing a position of each of the pre-calibrated feature points at a centroid of the nut of the bridge bolt as an origin of a polar coordinate.