HC-SR04 推薦指南：2026 年性價比最高的超聲波測距模組

This guide compares three ultrasonic distance sensor modules for different use cases in 2026: the budget HC-SR04 for indoor beginners, the waterproof HC-SR04 variant with IP65 rating for outdoor/wet environments, and the US-100 with built-in temperature compensation for higher accuracy. Each option is evaluated on price, pros/cons, and ideal user scenarios to help buyers make a cost-effective choice.