Green Room : A climate controlling grow-box for growing mushrooms and greens.

Abstract: This report covers a project on a partially automated aeroponic and fungi growing system. The purpose is to evaluate if an enclosed space system can be automated to produce healthy crops of greens and fungi, and investigate how well the system can switch between these two growth modes. Factors that will be automated include regulation of temperature, humidity, air ventilation, and light exposure time. The research will be focused on Romaine lettuce and Golden Oyster mushroom. The methods used include research, hardware setup, software programming, chassis construction, and experiments. Relevant factors for the growing environment, such as lighting, temperature, and nutrient solutions were studied. The hardware components used in the project can shortly be described as follows. A real time clock ensure accurate timing for the microcontroller that regulates the indoor climate based on sensor readings. LEDs light up the chamber and a humidifier provide the roots access to a nutrient solution. A fan provides cooling, and filters block out unwanted microorganisms and fungi spores from the ventilation air. A display provides the user with relevant information. The system code written in C++ contain six main functions and two support functions. Depending on the growth mode, climate control functions are selected. The system has control variables allowing the administrator to set threshold levels for humidity and nutrient spray periods. The outer case of the chassis was made out of painted acrylic to block out light and retain moisture. The water-nutrient solution basin was designed to avoid leakage, net cups hold the plants in a raised bed, a base plate acts as flooring for the mushrooms, as well as a placement enforcer for the humidifier. An inner roof separates the moist growth chamber from the electronics compartment above. Two experiments were conducted in separate prototypes simultaneously for green sand mushrooms. For the mushroom experiment, a grow kit was installed after thorough cleaning. The fruiting process was monitored and photographed daily. Results showed successful mushroom growth and healthy fruiting bodies. For the greens experiment, a nutrient solution was mixed and lettuce seeds were placed in rock wool cylinders that were installed in net cups. Photographs were taken every three days to track the progress. The lettuce seeds germinated and started growing. Control variables were altered multiple times to maximize performance but optimal settings were not found. The plants died whilst unsupervised. The experiments were partially successful and demonstrated potential for growing both greens and mushrooms. The prototype was effective in maintaining set temperature and humidity levels. The parameters necessary for successful growth was effectively automated and the system has great potential for further improvements and automation.