Three commonly used measurement methods

It includes direct measurement, optical measurement and mechanical measurement.

1. Direct measurement: Direct measurement is one of the simplest, most direct and most commonly used measurement methods. Refers to the way of directly measuring the body itself, such as directly measuring the length, width, height and diameter of the workpiece with tools such as straightedge, caliper and gauge.

2. Optical measurement: Optical measurement is a method of measuring the workpiece by using optical elements and measuring scales. Including plane mirror method, projector method, point shadow method, gear detection method, photography method, coordinate measuring machine and so on.

3. Mechanical measurement: Mechanical measurement refers to the method of measuring by using mechanical principles, including reduction ratio principle, lever principle, cycloid principle and helix principle. Among them, the principle of reduction ratio is commonly used, that is, how many turns or angles the rotating shaft has turned is measured by measuring instruments such as screw micrometer and micrometer, and then the length or angle to be measured is calculated by the reduction ratio of the reduction mechanism.