An open-source spectral measurement platform for plant reflectance and material identification.

Spectral sensing plays a crucial role in agriculture, environmental monitoring, and material characterization, providing non-destructive insights into chemical composition and physiological status of plants. Commercial spectrometers, however, are often expensive and lack modularity, which limits their adoption in educational, research and field applications. The developed open-source spectral measurement platform addresses this gap by offering a low-cost, customizable solution for reflectance analysis in plant leaves and diverse materials. The system integrates a Hamamatsu C12880MA miniature spectrometer with dual illumination: a white LED and a 3 mm incandescent bulb, covering 340-850 nm. Control and acquisition are managed by a Teensy 3.2 microcontroller through a Python interface that enables calibration and data storage. The modular enclosure, fabricated via RepRap-class fused filament-based 3D printing and PVC components, ensures flexibility and reproducibility. Validation tests demonstrated accurate wavelength alignment when exposed to laser sources, with peaks detected at 407 nm and 663 nm, and mean squared errors of 0.0131 and 0.0208, respectively. Ambient light comparisons with a commercial OSHP spectrometer yielded an MSE of 0.0105 (