Changes in wind direction can be measured by the dogvane

and then adjust fans to follow changes in wind direction for high-quality power generation

so as to reduce costs. Using wind vane structure

the vane wheel is set by the direction cam and the angle cam and the vane body with equal-strength cantilever beam pasted fiber Bragg grating（ FBG） are fixed to the base. The vane wheel rotates by the action of the wind and then the direction cam and the angle cam are driven. Then equal strength cantilever beam products deflection by impact of the cam

resulting wavelength shift of FBG pasted on it. According to the mathematical model

the rotation angle of wind vane that is wind direction can be obtained by amount of wavelength shift. The analysis of data on FBG dogvane by wind tunnel experiment shows that the starting wind speed is 1. 2 m / s

nonlinear error is 7. 92 % FS

sensitivity is1. 47 pm /（ °）

repeatability error is 6. 03 % FS.