The main power input is
J4 and is typically paired with a VOXL Power Module v3, which provides the up to 6A momentary inrush current and provides two I2C based power monitoring ICs, providing PX4 the battery status.
The recommended cable is
MCBL-00001 for this interface.
- Connector on board : SM12B-GHS-TB(LF)(SN)
- Mating connector : GHR-12V-S
With the VOXL PM attached, you check the battery using
px4-listener battery_status command after getting a shell to VOXL 2.
Here’s an example from a 3S battery:
px4-listener battery_status TOPIC: battery_status battery_status_s timestamp: 1080175258 (0.059704 seconds ago) voltage_v: 12.6662 voltage_filtered_v: 12.6659 current_a: 0.1758 current_filtered_a: 0.1791 average_current_a: 0.0000 discharged_mah: 51.6742 remaining: 1.0000 scale: 1.0000 temperature: nan cell_count: 3 voltage_cell_v: [4.1200, 4.3200, 4.2200, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000, 0.0000] max_cell_voltage_delta: 0.0000 capacity: 0 cycle_count: 0 run_time_to_empty: 0 average_time_to_empty: 0 serial_number: 0 manufacture_date: 0 state_of_health: 0 max_error: 0 interface_error: 0 connected: True source: 0 priority: 0 id: 1 is_powering_off: False warning: 0
The voxlpm PX4 driver monitors both battery and companion computer regulated voltage.
The driver runs in PX4 on the DSP, and interfaces through SSC QUP2.
You can’t get to this I2C bus through Ubuntu at this time.