What is smart dust technology?
Smart dust technology is exactly what it sounds like: internet-connected dust particles. Well, not exactly. They are sensors the size of dust particles, of around one millimetre. They can monitor and sense signals from the environment, such as sound, temperature and humidity. These sensors connect wirelessly to a network and work as the sensing layer of an IoT system.
Due to their size, they are not expected to have a long battery life or range, and are expected to stay suspended in the environment for a long time, just like dust particles. They are usually referred to as “motes” or Microelectromechanical systems (MEMS). Smart dust may one day completely transform IoT, much like how IoT transformed the world.
In some ways, MEMS are similar to nanobots, except smart dust is a sensor network and more of an input device, while nanobots are more of an output device. Even though smart dust has yet to find popular applications, advances have been made over the three decades since the idea emerged in the 90s.
Smart dust: origins
Dr Kristofer S.J Pister is considered to be the inventor of smart dust. The idea first came up in a workshop conducted at RAND Corporation, an American think tank. In 1997, Dr Pister, along with his colleagues Joe Kahn and Bernhard Boser from the University of California, submitted a research proposal to DARPA and coined the term Smart Dust.
The proposal was to create tiny wireless sensors, one cubic millimetre in size, and deploy them rapidly on a battlefield to conduct surveillance on enemy territory. The project resulted in a working sensor which, in a test, was able to detect and track the acceleration and movement of vehicles. Dr Pister later founded Dust Networks, which develops low power wireless mesh networks.
How it works
Smart dust works like the sensors used in other IoT systems, except these devices are much smaller and far greater in number. Together they form wireless sensor networks, connected to a base network and transmitting their data over small distances.
Making them small is the major technical hurdle, which is why they are usually 3D printed. Making a small enough power source is an even bigger problem than making the sensor small. To solve it, researchers have used power generation devices such as solar panels or vibration motors to generate power instead of storing it. Letting the device sleep most of the time, waking up only to collect and transmit data, is another strategy to keep power demands low.
Applications of smart dust
Smart dust can change how IoT and AI are used in agriculture. Currently, most AI systems rely on computer vision to check for pests or infections. Robots that pluck fruit use cameras to identify the fruit and check whether it is ripe enough. While these technologies automate a lot of work in agriculture, they are not significantly better than humans at identifying infections or ripeness.
With smart dust, it may be possible to identify infectious organisms well before they create any discolouration. Sensors that can quantify the level of particular chemicals in fruit could lead to robots that are better than humans at judging ripeness. Smart dust can also be deployed for weather forecasting, which would improve it significantly.
Another application is monitoring industrial processes. Large scale deployment of sensors can detect cracks in machinery or leaks in tanks well before they are noticed or start affecting performance. This kind of monitoring is already possible today, as sensors are already monitoring real world systems such as swimming pools, where connected devices track and control conditions remotely.
The impact of nanobots in healthcare has been widely speculated. Smart dust could create a similar impact on how diseases are diagnosed. Diagnoses could be far less invasive, yet more detailed and accurate, with the help of smart dust.
Where are we now?
Smart dust is yet to see any consumer applications, but wireless sensor networks built from centimetre scale devices are already used in many industries. Centimetre scale sensors are already seeing applications across industries, where they monitor a wide range of processes.
Innovation at the University of Michigan
In 2008, researchers from the University of Michigan produced the Phoenix processor for sensing applications. At a size of 915 x 915 microns, the processor has low power requirements through a sleep management strategy and other techniques.
Using this processor, another team from the University of Michigan made the Michigan Micro Mote, a two-millimetre computer capable of collecting data, processing it and giving results. They combined the Phoenix processor with solar cells that can produce power from ambient light, even without natural sunlight.
The computer is expected to work perpetually, and by generating power from within, the team overcame the major deterrent to reducing the size of computing systems: the battery. Labelled the M3, the Michigan Micro Mote comes in three variants, capable of sensing temperature, sensing pressure and taking pictures respectively.
Innovation from other parts of the world
A couple of years ago, HP announced CeNSE, or Central Nervous System for the Earth, which aimed to use nanoscale sensors to monitor the environment. The idea is to monitor large scale systems such as bridges, roads, other infrastructure, aircraft and industrial plants. The sensors are tiny accelerometers capable of sensing motion and vibrations.
An operating system developed for low power wireless sensor networks was first released in 2000. The OS is designed around the low power and memory requirements of sensors like smart dust. It started at UC Berkeley in collaboration with Intel and Crossbow Technologies as part of the DARPA Nest program and has since grown into an international consortium.
A variant of smart dust, called Neural Dust, aims to sense signals from the human brain. Researchers from the University of Berkeley gave the first demonstration of neural dust using a wireless sensor 3mm long and 1mm across. They attached it to the sciatic nerve of a rat and recorded its activity in response to stimulation of its foot. The system used ultrasound to both power the device and take readings from it.
Similar technology may come from Neuralink, the company owned by Elon Musk, which aims to create a brain-computer interface and possibly treat degenerative disorders like Parkinson’s. The company has claimed that, using its technology, a monkey was able to control a computer. It uses electrodes inserted into the brain that are already thinner than a human hair. It may not be long before sensors could be sprinkled onto the brain to study neural activity and possibly control devices.
Major hurdles
Reducing size without compromising the life of the sensor will be a major technological challenge in developing smart dust technology. As the examples above show, one option may be for the sensors to generate their own power. Vibrational motors may one day generate enough power to run a heart monitoring sensor using the heartbeat itself, or to monitor heavy machinery using its own vibrations.
Beyond the technological challenges, smart dust raises a lot of privacy concerns. Sensors that are invisible to the naked eye, floating around and monitoring your actions, are definitely creepy. As with the explosion of smartphone cameras, smart dust may create privacy issues of its own.
Another hurdle is cost. For smart dust to be effective, it must be deployed in large numbers, and for that to be possible, costs must be kept very low.
What this means for your business
Smart dust may still be years away from everyday use, but the shift toward connected, sensor-driven systems is already here. Businesses that start building on that foundation today will be best placed to adopt whatever comes next. If you are exploring what connected sensing could do for your operations, our team can help you plan and build the right IoT solutions for your business.
