3D Printed Sensors Could Offer Earlier Warning of Wildfires and Chemical Leaks

A forest fire can spread unbelievably fast, which means that early detection is critical. The current systems in place for detecting the spread of forest fires, however, aren’t perfect. Watch towers, satellites and costly fixed sensors are the standard at the moment, but a group of researchers from King Abdullah University of Science and Technology (KAUST) have developed a new, better method that involves a series of inexpensive, disposable 3D printed sensors wirelessly linked to a few fixed nodes.

The work was documented in a paper entitled “3D-Printed Disposable Wireless Sensors with Integrated Microelectronics for Large Area Environmental Monitoring,” which you can access here. Authors include Muhammad Fahad Farooqui, Muhammad Akram Karimi, Khaled Nabil Salama, and Atif Shamim. The system is designed to detect not only fires, but industrial chemical leaks that can pose a threat to public health. The sensors can detect heat and lowered humidity, which signify a forest fire, as well as the toxic gas hydrogen sulfide. Dispersed over a large area, the sensors would communicate with a few larger, fixed nodes, wirelessly transmitting the data in a lifesaving Internet of Things application.

According to the KAUST team, cost has been an issue in developing sensor networks across a large area, but the sensors created by the researchers could ultimately turn out to cost less than one dollar apiece. Their method of production currently involves 3D printing a cube that encloses a microelectronic circuit board, also 3D printed, as well as a battery. The fire- and gas-detecting sensors are inkjet printed directly onto the walls of the cube. Associate Professor of Electrical Engineering Shamim says that the combined 3D and inkjet printing process makes production fast, inexpensive and environmentally friendly.

“Material is deposited in precise quantities only at the desired location,” he said. “Traditional manufacturing methods take bulk material and gradually remove material to realize the final shape, resulting in significant wastage.”

Production will eventually make the process even faster and cheaper, as well. Right now, separate 3D and inkjet printers have to be used to create the nodes, but soon the two processes will be combined into one machine, which will cut back manufacturing time significantly. In addition, the team wants to make the sensors solar-powered, meaning that they can be deployed in remote locations without battery maintenance. It will also make them cheaper, as will scaling up manufacturing and mass-producing customized chips rather than the circuit board of the current model.

“Inkjet-printed solar cells have already been demonstrated,” Shamim said. “Eventually we want to get rid of the battery entirely.”

The 3D printed nodes, which were desgined by PhD student Farooqui, have been tested both in the lab and in the field. They can withstand being dropped from high up as well as temperatures of up to 70°C, which is adequate in order to provide an early warning in the case of a forest fire.

Currently, there are several fires burning in the United States, covering thousands of acres. Efforts are underway to control them and prevent loss of life and property, but once a wildfire spreads, it’s a challenge to contain. Better early detection systems, like these 3D printed nodes and sensors, could go a long way in terms of catching wildfires at the very beginning and stopping them before they have a chance to get quite so large and destructive. Discuss in the 3D Printed Sensors forum at 3DPB.com.