智慧菇舍環境監控系統設計

Abstract

中文摘要 本報告旨在針對傳統菇舍受極端氣候影響導致產量下滑、溫濕度管理不易的痛點，設計一套專為高濕環境打造的「智慧菇舍溫度量測與環境監控系統」，以保障香菇各生長階段之最適微氣候環境。主要過程與方法上，系統前端選用具備抗潮濕且高線性度的電流輸出型 AD590 溫度感測器（1μA / K），透過精密金屬膜電阻將微安培電流轉換為下地電壓訊號，並搭配 TL431C 基準源扣除 0∘C 時的直流零點偏移；後級採用超低溫漂的 OP07CP 精密運算放大器組建 100 倍差動放大器，將 0~50∘C 的溫度範圍線性放大為 0~5V 訊號，最後送入微控制器進行 ADC 取樣、1602 LCD 顯示及繼電器連動；同時整合 RC 低通濾波、雙絞隔離線單端接地及移動平均演算法以全面抑制馬達突波與環境雜訊。研究結果成功實現了以 100mV/∘C 高精度線性輸出的溫控電路，並透過實驗室兩點校正法將誤差控制在±0.1∘C 內；此成果可直接應用於智慧菇舍之排風、水霧降溫閉環控制，亦能延伸推廣至農業溫室多通道量測、AIoT 遠端環控與工業級高濕度環境監測等領域。

Abstract This study presents the design of an intelligent mushroom house temperature measurement and environmental monitoring system tailored to overcome the vulnerability of traditional mushroom sheds to extreme climate variations, ensuring optimal microclimates across mycelium growth and fruiting stages. To address the harsh conditions of high humidity and potential line resistance oxidation, a current-output AD590 integrated circuit temperature sensor (1μA / K) encapsulated in a waterproof stainless steel probe is employed. The microampere current signal is converted into a base voltage using a precision ground resistor, followed by a DC offset elimination circuit powered by a high-stability TL431C reference voltage source. An ultra-low-offset operational amplifier (OP07CP) is configured as a differential subtractor amplifier with a gain of 100, linearly mapping the temperature span of 0∘C to 50∘C to a standard 0V to 5V output (100mV / ∘C ) for microcontroller ADC acquisition, on-site 1602 LCD indication, and closed-loop relay actuation for ventilation fans and mist cooling systems. Comprehensive anti-interference measures—including a first-order RC low-pass filter ( fc ≈ 159 Hz) , shielded twisted pair cabling with single-point grounding, power decoupling, and a moving average digital filtering algorithm—are implemented to suppress motor switching surges and spatial electromagnetic interference. Experimental zero and span calibrations demonstrate an overall system error within ± 0.1∘C . The proposed system provides a robust, low-drift hardware foundation for smart greenhouse microclimate regulation and exhibits significant potential for multi-channel AIoT agricultural expansion.