DEVELOPMENT AND EVALUATION OF A MULTI-CHAMBER ENVIRONMENTAL CONTROL SYSTEM

Abstract

Growth chambers are control devices used in plant research. However, their high costs limit their application to a single environment, which compromises their efficiency for the generation of experimental data. The objective of this research was to design, construct, and assess the performance of a multi-chamber environmental control system capable of regulating both air temperature (AT) and relative humidity (RH). The evaluation was carried out using Syngonium podophyllum Schott plants. Three constant target temperature values (18, 23, and 40 °C) were established, together with a target RH value of 60 %. AT and RH data were recorded every 4 min for three days. The system was built with 15 growth chambers and the following devices: output (AT, RH, and lighting control), input (sensors), and central control managed by two Arduino^® Mega 2560 based microcontrollers, plus a programmable logic controller. Programming was done in open-source languages such as Arduino^® and Python^®. Results indicate that the absolute error (AE) and standard deviation (SD) in AT were higher when the target temperature was lower (AE = 0.59 °C and SD = 0.93 °C) compared to the other higher target temperatures (AE = 0.31 °C and SD = 0.43 °C at 23 °C, and AE = 0.25 °C and SD = 0.51 °C at 40 °C). On the other hand, the AE in RH increased as temperature increased, going from AE = 3.75 % and SD = 5.12 % at 18 °C, to AE = 9.23 % and SD = 10.77 % at 40 °C. The use of open-source technologies allowed the construction of a multi-chamber environmental control system capable of replicating controlled environments.