Modeling Variability in the Readings of an 8-channel Color Sensor and Its Uncertainty Estimation

This paper presents the implementation of an illuminance meter based on the 8-channel AS7341 sensor in conjunction with the ESP32 board. The sensor mounted on a SoC board can be implemented as an illuminance meter under the conditions specified. The results obtained are compared with the Gossen illuminance meter following the distance photometry, fitting curves for 11 illuminance levels and 4 positions to calculate the coefficient of determination for all distances and supply voltages. These results determine that the cubic polynomial interpolation technique is suitable to form the electromagnetic spectrum of the radiation source. After the implementation of the experimental scheme, it was found that the correction factor is almost constant for the eleven illuminances obtained by the prototype. The uncertainty of the equipment was calculated with the values of each intensity and distance, obtaining a constant. Therefore, the experimental scheme tested has an uncertainty of 12% regardless of the distance and illumination level parameters. The repeatability of the equipment is the major source of uncertainty. A better fixation of the distances and elements of prototype can reduce this value. After the development of the experimental work, it was determined that the AS7341 sensor mounted on a SoC board is a reliable illuminance meter.