Project background
Research and high-value crop growers demanded a sealed chamber with precise control over temperature, humidity, VPD, and CO₂. Off-the-shelf units lacked the setpoint resolution and programmability they needed.
Challenge
Coordinating heating, cooling, dehumidification, and CO₂ injection without oscillation. Handling the tight coupling between variables — for example, cooling lowering humidity capacity — without fighting the operator's intent.
Approach & solution
We designed a multi-loop controller that treats VPD as a first-class setpoint and orchestrates the underlying actuators accordingly. CO₂ is injected on a schedule tied to photoperiod and canopy activity. A color-coded HMI exposes both simple and expert modes for different users.
Results & benefits
The chamber held tight setpoints across diurnal cycles, giving researchers reproducible conditions across runs. The VPD-first control philosophy produced smoother crop behavior than prior temp/RH-only setups.
