Developed an autonomous, GPS-dedied, real-time indoor monitoring and inpection drone in a manufacturing facility. Each node measures VIO location, sonar altitude, speed and TOF against a CAD layout while visually inspecting components and objects.
Hardware Design
Custom drone navigation stack that integrates:
- BME688 environmental sensor (temperature, humidity, pressure, gas)
- VEML7700 ambient light sensor
- Capacitive soil moisture probe (custom design)
- SX1276 LoRa transceiver
- LiPo charging circuit with solar panel input
Power consumption averages 45 µA in sleep mode with hourly wake-and-transmit cycles. Nodes run for 6+ months on a 2000 mAh battery with typical solar harvesting.
Firmware
Zephyr RTOS provides the foundation, with a custom power management subsystem that transitions the MCU through multiple sleep states. The LoRaWAN stack handles over-the-air activation and secure data uplink to a gateway. Over-the-air firmware updates are supported via an A/B partition scheme.
Deployment
A pilot deployment of 24 nodes across a 10-acre research farm has been operational for 8 months with 99.3% data reliability. Gateway range exceeds 3 km in open terrain.