Octopus: A low-cost, modular environmental sensing platform for makers.

Environmental monitoring is increasingly critical in urban and ecological contexts, yet existing tools are often costly or closed-source. Octopus is a fully open-source hardware platform designed to enable low-cost, modular environmental sensing for makers, educators, and citizen scientists. The system is built around a compact, 4-layer custom-designed PCB and a 3D printed enclosure, supporting Arduino-compatible microcontrollers (Nano 33 BLE Sense or Nicla Vision) and varied plug-and-play sensors, including particulate matter, GPS, temperature, and humidity. Octopus emphasizes ease of assembly, flexibility of deployment, and reproducibility. All hardware, firmware, and mechanical design files freely available. Devices can be built for less than 100 USD using widely available tools, significantly lowering the barrier to entry for environmental sensing. We provide complete documentation, including build instructions, firmware libraries, and example applications. Compared to existing citizen-science devices, Octopus offers an extensible and adaptable platform to support hands-on environmental research, educational use, and grassroots sensing initiatives.
The uploaded files support the Octopus open-source environmental sensing platform. They include PCB design files, 3D-printable enclosure models, and Arduino-compatible firmware. These materials provide everything needed to reproduce, assemble, and deploy the device for low-cost environmental monitoring in research, education, or citizen science.