As urban populations continue to grow around the world, the need for fresh food, especially produce, is becoming critical. To help address this need, a team from the University of Electro-Communications in Tokyo has developed a compact, IoT-enabled hydroponic planter system.

The planter was designed for consumers with minimal agricultural knowledge and is meant to occupy vacant spaces in urban areas—rooftops and verandas at office buildings, hospitals, schools, etc. It is the team’s belief that these planters can create a new industry for food growth by turning consumers into producers.

“To ensure even the most casual of growers can succeed with the planter, we developed a remote monitor and control system from low-end, high-performance microcomputer boards and open-source software,” explained Professor Akashi Satoh of the research team. “It’s not designed for mass production, but for recreation where there’s no need for optimal control and high-accuracy sensors.”

The planter is based on a vertical pipe for suspended cultivation. Its simple structure allows for easy installation, maintenance, and repair and can be used for both fruits and vegetables. Water is stored in a tank and pumped up into two vertical pipes that shower the plant roots. With no obstacles, plants can extend freely into the air and are protected from root rot–a common problem for hydroponic cultivation in the summer. The full structure can be viewed below in Figure 1, which showcases the cultivation of strawberries.

 

Figure 1: The Hydroponic Planter’s Structure During Strawberry Cultivation

The planter uses a variety of sensors to measure liquid fertilizer concentration, water level, water temperature, luminance, temperature, and humidity. The measurement circuit of the water level can be seen in Figure 2.

 

Figure 2: Water Level Measurement Circuit

While a smartphone dashboard can provide real-time data monitoring and pump control, additional monitoring is needed in remote cultivation. To provide users with as much information as possible, the team equipped the planter system with an image monitoring service. Because transmitting high-resolution video on a low-bandwidth service can be difficult and costly, images of the planter and motion detection data are sent to the dashboard every few minutes.

 

Figure 3: Example Network for Remote Management

As the team continues to tweak the planter system, it will look for ways to add more features while keeping costs low. Still, they believe the system’s simplicity is an excellent way to get urban hydroponic planting off the ground and to transform how consumers grow produce.

“Moving forward, we are going to implement adaptive control for the water pump and liquid fertilizer concentration based on the weather,” said Professor Satoh. “We would also like to implement a cultivation advisory function and a communication system between users.”

For more information on hydroponics, visit the IEEE Xplore Digital Library.