Jul 24 2017
In a disaster, early warning is paramount to escaping from a danger, such as a chemical leak or a forest fire. Motivated to advance safety features, a team from KAUST is employing 3D printing to develop an economical, reliable system to signal danger1.
Current early warning systems depend on satellite monitoring, expensive fixed sensors or watch towers. The system, created by a team headed by Associate Professor of Electrical Engineering Atif Shamim, works by saturating high-risk areas with throwaway packages of sensors (sensor nodes) that are connected wirelessly to smaller number of fixed nodes that raise the alarm.
Shamim views this as part of a progress towards an internet of things.
Where infrastructure makes smart decisions in place of humans.
Atif Shamim, Associate Professor of Electrical Engineering
This proof-of-concept research produced small sensors that can sense heat and low humidity, both indications of forest fires, as well as hydrogen sulfide, a poisonous industrial gas. These small sensors were inkjet-printed onto a 3D-printed, 2-cm3 node consisting of a battery and microelectronic circuit board together with an antenna that conveys in any direction.
Shamim says they adopted 3D and inkjet printing, the “next revolution in industrial manufacturing,” because they are additive processes, making them quick, cost-effective and environmentally friendly.
Material is deposited in precise quantities only at the desired location. Traditional manufacturing methods take bulk material and gradually remove material to realize the final shape, resulting in significant wastage.
Atif Shamim, Associate Professor of Electrical Engineering
Designed by Ph.D. Student Muhammad Farooqui, the node has been analyzed in lab as well as in field. It survives being dropped from a height and temperatures up to 70 ºC which, says Shamim, is, “good enough to give an early warning in cases of wild fire.” He believes it is the first, “low-cost, fully integrated, packaged, 3D-printed wireless sensor node for real-time environmental monitoring.”
Presently the nodes are constructed using a combination of 3D and inkjet printing since no 3D printer can exactly deposit all the materials into the intricate design. However, they will soon be manufactured by a single machine, which will significantly decrease manufacturing time.
The following step is to integrate an energy source, making the nodes self-sustainable in distant locations.
Inkjet-printed solar cells have already been demonstrated. Eventually we want to get rid of the battery entirely.
Atif Shamim, Associate Professor of Electrical Engineering
Removing the battery, along with scaling up manufacture and mass-producing tailor-made chips instead of the circuit board, will reduce the cost of each sensor node lower than a dollar, which is a small price to pay for a technology that could save several thousands of lives.
Reference
1 Farooqui, M.F., Karimi, M.A., Salama, K.N. & Shamim, A. 3D-printed disposable wireless sensors with integrated microelectronics for large area environmental monitoring. Advanced Materials Technologies 2017, 1700051 (2017).|