Abstract
Farmers have a serious problem with bird infestation, which causes large post-harvest losses in fruit and grain output. Because of environmental issues and avian adaptability, traditional deterrents like chemical repellents and scarecrows frequently don't work. This study presents the design and analysis of a wind-powered bird repeller that uses natural wind energy to generate mechanical motion and impact-driven acoustic signals. Rotating blades convert wind energy into torque, which drives an oscillating arm to strike metallic sound plates, producing irregular and high-intensity sounds that disturb and repel birds. Blade Element Momentum (BEM) theory was applied to predict aerodynamic performance and torque output, while MATLAB/Simulink was used for system modeling, torque analysis, blade rotation dynamics, impact frequency, sound pressure levels (SPL) and dynamic response evaluation. The results obtained shows that the rotor generated up to 2000 W of wind power at a radius of 1 m, while a strike frequency of 100 impacts/s at a 0.1 m radius. Modal analysis showed a reduction in resonant frequency from 18 Hz to 3 Hz as plate radius increased from 0.02 m to 0.1 m. additionally, at 10% acoustic efficiency, sound pressure levels (SPL) increased from 170 dB to 185 dB with a striker mass range of 10 g to 50 g. The proposed design is sustainable, low-cost, and environmentally friendly, showing strong potential to reduce crop damage through unpredictable, non-harmful bird deterrence.