AquaponicsOS: Much Ado About Sensors

The senses are a kind of reason. Taste, touch and smell, hearing and seeing, are not merely a means to sensation, enjoyable or otherwise, but they are also a means to knowledge – and are, indeed, your only actual means to knowledge.

- St. Thomas Aquinas 

AquaponicsOS' concept is built upon three rapidly evolving technologies: aquaponics, artificial intelligence and sensors. However, A.I. and sensor technology, by being coupled to Moore's Law, are growing at an exponential rate. This forces us to take a "Kurzweilian" non-linear view of what it implies as we move forward. Most of today's hype on the Internet of Things (IoT) stems from this non-linear improvement in the technology. In other words: what happens when sensors transition from being bought by the unit to being bought by the pound? No one really knows how this market will evolve but, just as the microprocessor revolution of the 1970's, everyone thinks that something big is going to happen.

Fig 1. was presented by Dr. K.E. Petersen in "the 13th International Conference on Solid-State Sensors, Actuators and Micro-Systems, 2005". The blue line represents the well-known Moore's Law that states that transistor density of Integrated Circuits doubles every 18 months. The lower one represents the transistor density for different Microelectromechanical Systems (MEMS). [1]

Fig. 1

MEMS are what make our smart phones possible. They are the tiny cameras, accelerometers, compasses and gyroscopes that we now take for granted. As they continue to become cheaper they are starting to be used as sensing devices of our economy. For example, sensors can be put in concrete to measure tiny variations in tension and thus avoid costly human inspections [2]. The same is true for accelerometers in our cars that might give us lower insurance fees. Accelerometers are now able to predict when a cow is in heat! [3] They are our economy's evolving nervous system. Figure 2 shows the maturity of cell phone MEMS according to Yole Developement [4].

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Figure 2

MEMS are also being used to sequence DNA, thus combining two exponential technologies together [5]. As MEMS continue to decrease in size they might be the precursors of Feynman's nano-technology vision described in his talk "There is Plenty of Room at the Bottom". Again, nobody knows what this will be, but we are currently surfing different exponential technologies that are quite likely to converge and influence one other.

Before speculating about the future, let's go back to basics: how does one of these sensors work? (not an electrical engineer so apologies in advance for any inaccuracy!) At its basics, if we want to "sense" anything about the world we need three basic components: a sensor, a microcontroller and a radio transmitter. For example, if we wanted to measure pH levels in water we would need a system as presented in Figure 3.

Figure 3

The retail price for a pH meter is ~$10, a 16-bit microcontroller is ~$2 and a radio transmitter is also ~$2. An electrical engineer might have a more detailed idea of what exactly is needed and at what price it could be obtained. Nevertheless, a minimum ballpark figure would be somewhere between $10 and $50 for hardware alone. Osmobot has designed a kit that senses pH, dissolved oxygen and various other parameters for $499. As it might prove too expensive for a DIY enthusiast, a more modular and simplistic approach might be better. YSI is a manufacturer that offers sensor solutions for aquaculture. (There is a list of companies offered in Stanford's sensor course)

The key concept is to lower the sensor price range by developing software on top of the cheapest and most standardized hardware available. Ideally one would make bulk orders of sensors, microprocessors and radio transmitters from China and develop an open source community to leverage this technology. The economic equation one would make in the end is how much savings in reduced labour and increased yields would be produced by such a system. It is a market in which every penny counts and, whatever solution emerges, it will have to be optimized at the "electronic" level. This is why Vertical Farms might be the first to reach an economic feasibility level that will justify an investment in monitoring systems. Moreover, we only explored the sensing part of the equation. In order to provide a reliable service there must be sensing, information processing (in the cloud being the most economic option) and transmission to actuators. Think of it as an Homeostatic system. 

Ideally, AquaponicsOS would focus on the software side and manage the services in the cloud. However, given the early stage development of the technology, it might seem a good idea to give the first steps in developing open source software for a low cost modular sensor system upon which other people might improve on. This is necessary to harvest data, otherwise that information will not even be available. The important concept is to think about AquaponicsOS above the level of a single device. It would be monitoring every possible aspect of each plant and hacking nature's different phosphate, nitrate, ammonia and oxygen cycles to optimize food production. It would do it with algorithms optimized for each type of crop.

The business plan should foresee the exponential nature of sensor technology and incorporate it as a key strategy. This means that it might make sense to anticipate falling prices even before they reach that point and thus have data as a competitive advantage. Furthermore, the MEMS market will be intimately involved with the vertical farm information services industry. Being able to strike deals with it and act as part of its supply chain should be another key element of the strategy. Figure 4 shows the top 30 players in the industry.[6]