Mechanism Design of Four-point-type Mutifunctional Protractor

In this paper,the mechanism of four-point-type mutifunctional protractor is designed. The protractor is composed of vernier caliper,a fixd arm,a movable arm, graduated disc,angle vernier and so on. The movable arm can be translated and rotated, which extend the angle measuring limits.This protractor can measure the angle and length by integrating all function of the vernier caliper.