Merge pull request #1416 from sjwilks/calibrate_usb

Don't go into an error state if we are temporarily powering via USB on the bench

src/modules/commander/commander.cpp

@@ -1407,8 +1407,8 @@ int commander_thread_main(int argc, char *argv[])
 			last_idle_time = system_load.tasks[0].total_runtime;
 
 			/* check if board is connected via USB */
-			//struct stat statbuf;
-			//on_usb_power = (stat("/dev/ttyACM0", &statbuf) == 0);
+			struct stat statbuf;
+			on_usb_power = (stat("/dev/ttyACM0", &statbuf) == 0);
 		}
 
 		/* if battery voltage is getting lower, warn using buzzer, etc. */
@@ -1418,7 +1418,7 @@ int commander_thread_main(int argc, char *argv[])
 			status.battery_warning = VEHICLE_BATTERY_WARNING_LOW;
 			status_changed = true;
 
-		} else if (status.condition_battery_voltage_valid && status.battery_remaining < 0.09f
+		} else if (!on_usb_power && status.condition_battery_voltage_valid && status.battery_remaining < 0.09f
 			   && !critical_battery_voltage_actions_done && low_battery_voltage_actions_done) {
 			/* critical battery voltage, this is rather an emergency, change state machine */
 			critical_battery_voltage_actions_done = true;