Angle measurement technology of fully automatic image measuring instrument

Improving the accuracy of automatic video measurement instruments has always been a challenge. There are two main methods for measuring angle with automatic imagers: tangent method and sampling point calculation method. The tangent method only requires the operator to rotate the inner line of the lens or screen, align it with the two edges of the measuring workpiece, and then use an encoder or circular grating to count the angle.

The tangent method is simple to operate, but has low reading density, making it suitable for rapid batch testing. If the angle density reading requirement of the tested object is high, another method, namely the sampling point calculation method, is more suitable. All geometric elements have certain combinations, including the Urelement of lines, curves and arcs. A two-dimensional plane angle is composed of two basic geometric elements: straight lines, which are composed of countless points. Therefore, regardless of whether the angle measurement is accurate or not, the mining point is the most crucial.

Automatic image Measuring Instrument: The angle measurement technology of linear acquisition should be as long as possible.

Due to limited screen display and high magnification (usually 0.7-4.5-34x-220x), the workpiece size in the screen display section is only a few millimeters. Many surveyors only use it to collect the points and lines displayed on the screen during testing. If there is a deviation in the collection point, the shorter the linear segment, the greater the deviation in the measurement angle value. The longer the linear segment, the smaller the deviation in the measurement angle value. So when we measure the angle, we try to collect the lines on both sides of the angle. If the screen display range is too small, we can move the workbench and select a point at the starting point of the straight line where the angle is located, and then select a point at the end point, which can greatly reduce the error of angle measurement.