Effect of adjusting the height of an LED light source on plant yields in cultivation systems

Many plant cultivation systems using an LED light source have been developed. In such systems, the height of the LED light source above the plants is generally fixed, and this height is set so that the plants do not come in contact with the light source during cultivation. As a result, in the early stages of growth, the light source is located a long distance away from the plants. Therefore, it is logical to assume that cultivation efficiency could be improved by altering the height of the light source as the plants grow. In previous studies, the light source manually adjusted. However, in this study, adjusting the LED light source with a robot arm based on plant height is proposed, and additionally, a method of measuring the height of the plants with ultrasonic sensors was adopted.