The Emerald Module: Power to the System

The Emerald module is a battery power supply for the GEMS system. It is connected to other modules by a flat cable consisting of DC power lines and a CANbus communication pair. The module includes a microcontroller that is used to monitor the battery voltage and discharge current. Battery information can be shared with other modules.

Battery safety is achieved with reverse polarity protection, overcurrent protection and the ability to completely shutdown the system. The status of the module is shown by three LEDs. A red LED indicates that the battery is incorrectly inserted into the holder, a yellow LED lights when the battery is charging, and a green LED lights when the module is powered by the battery.



  • 90mm x 40mm
  • 3.3V system
  • 18650 lithium-ion battery with charging circuit
  • Reverse polarity protection
  • Overcurrent protection (7A)
  • Battery voltage and current measurement
  • Status LEDs
  • ESP32 C3 microcontroller
  • USB-C connector
  • CAN bus
  • Button


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