msg文件夹里共有116个.msg文件、1个CMakelist.txt文件、2个文件夹，如图：
（点击目录跳到源码处）
目录
- actuator_armed（执行器）
- actuator_controls
- actuator_direct
- actuator_outputs
- adc_report
- airspeed
- airspeed_validated （空速验证）
- battery_status （电池电压电流温度s数等数据）
- camera_capture
- camera_trigger
- collision_constraints （碰撞约束条件）
- collision_report
- commander_state
- cpuload （cpu使用率、ram使用率）
- debug_array
- debug_key_value
- debug_value
- debug_vect
- differential_pressure
- distance_sensor
- ekf_gps_drift
- ekf_gps_position
- ekf2_innovations
- ekf2_timestamps
- esc_report
- esc_status
- estimator_status
- follow_target
- geofence_result
- gps_dump
- gps_inject_data
- home_position
- input_rc
- iridiumsbd_status
- irlock_report
- landing_gear
- landing_target_innovations
- landing_target_pose
- led_control
- log_message
- manual_control_setpoint
- mavlink_log
- mission
- mission_result
- mount_orientation
- multirotor_motor_limits
- obstacle_distance
- offboard_control_mode
- optical_flow
- orbit_status
- parameter_update
- ping
- position_controller_landing_status
- position_controller_status
- position_setpoint
- position_setpoint_triplet
- power_button_state
- power_monitor
- pwm_input
- qshell_req
- qshell_retval
- radio_status
- rate_ctrl_status
- rc_channels
- rc_parameter_map
- safety
- satellite_info
- sensor_accel
- sensor_baro
- sensor_bias
- sensor_combined
- sensor_correction
- sensor_gyro
- sensor_gyro_control
- sensor_mag
- sensor_preflight
- sensor_selection
- servorail_status
- subsystem_info
- system_power
- task_stack_info
- tecs_status
- telemetry_status
- test_motor
- timesync_status
- trajectory_waypoint
- transponder_report
- tune_control
- uavcan_parameter_request
- uavcan_parameter_value
- ulog_stream
- ulog_stream_ack
- vehicle_acceleration
- vehicle_air_data
- vehicle_angular_velocity
- vehicle_attitude
- vehicle_attitude_setpoint
- vehicle_command
- vehicle_command_ack
- vehicle_constraints
- vehicle_control_mode
- vehicle_global_position
- vehicle_gps_position
- vehicle_land_detected
- vehicle_local_position
- vehicle_local_position_setpoint
- vehicle_magnetometer
- vehicle_odometry
- vehicle_rates_setpoint
- vehicle_roi
- vehicle_status
- vehicle_status_flags
- vehicle_trajectory_waypoint
- vtol_vehicle_status
- wheel_encoders
- wind_estimate
（点击目录跳到源码处）
actuator_armed（执行器）
uint64 timestamp # time since system start (microseconds)
uint64 timestamp # time since system start (microseconds)
uint32 armed_time_ms # Arming timestamp
bool armed # Set to true if system is armed
bool prearmed # Set to true if the actuator safety is disabled but motors are not armed
bool ready_to_arm # Set to true if system is ready to be armed
bool lockdown # Set to true if actuators are forced to being disabled (due to emergency or HIL)
bool manual_lockdown # Set to true if manual throttle kill switch is engaged
bool force_failsafe # Set to true if the actuators are forced to the failsafe position
bool in_esc_calibration_mode # IO/FMU should ignore messages from the actuator controls topics
bool soft_stop # Set to true if we need to ESCs to remove the idle constraint
actuator_controls
actuator_direct
actuator_outputs
adc_report
uint64 timestamp # time since system start (microseconds)
int16[12] channel_id # ADC channel IDs, negative for non-existent
float32[12] channel_value # ADC channel value in volt, valid if channel ID is positive
