One of my more ambitious projects was creating a CBRN (Chemical, Biological, Radiological, and Nuclear) sensor that could be remotely fired from a weapon. The idea for this project arose while I was developing a concept for a multi-headed Nuclear/Gas/Chemical sensor, where a single computer unit would have interchangeable head units to detect different materials, thus reducing the number of sensors a soldier would need to carry. Initially, this idea was mentioned jokingly “It would be really cool if you could put it in a cannon…” but I took that as a challenge and a week later, with the help of an AR15 Can Launcher, the launchable CBRN sensor was developed.
The first prototype of the CBRN sensor was 3D printed using PLA for ease of use. The head units received power and communication through pogo pins on the top of the “Brain Unit”. The brain unit communicated using LoRa to a custom LoRa modem that we built for an Android phone and the sensor readings were input into ATAK’s RN Plugin.
After demonstrating the concept at an IoT Field Day, we drew attention from a SOCOM training facility that was looking for innovative ideas for the future warfighters. They asked if we could customize the concept to detect methane and launch the device using an M203 Grenade Launcher.
As this project was a novel effort, we could not use commercially available hardware. This led us to develop our own MCU based on an open-source Arduino layout. Our new chip included an industrial methane sensor, LoRa modem, and PCB antenna. All of this was designed in-house and several prototypes were hand-built.
The device was powered by a single rechargeable AA battery and had an average battery life of about 6 hours, which exceeded our requirements. The concept was straightforward: launch the sensor into a confined area where it would be unsafe to send humans or robots and gather measurements of the environment. However, executing this idea was challenging. Launching something like this from a low-powered AR15 can launcher was one thing, but an M203 grenade launcher has a much greater force. To accommodate this, the entire device needed to be encased in a protective material and a custom shell had to be milled.
For the device’s shell, I chose to use anodized aluminum because it does not spark. After months of designing, building, redesigning, and rebuilding, we finally developed a solution that securely housed the device and could withstand the forces of ignition and impact into a wall. Ten final shell prototypes were manufactured.
Despite the chip being completely encased and the shells being designed to withstand impact, we still encountered significant failures in testing, primarily related to the battery and the lifespan of the physical sensor.
Failing fast and learning from our mistakes enabled us to be agile in the redesign process. We are now exploring partnerships with vendors to provide advanced materials to handle the forces encountered.
Currently, the launchable sensor project is on hold as I focus on another project, but the development is far from over. I plan to resume development in early 2023.