Heron position controller

Python file for controlling position of Heron using GPS and ROS topics.

The heron has a variety of topics available with different information on all of them. The topics can be divided into multiple categories as follows:

Command input topics

/cmd_drive

Input :

• Left thruster : 0 - 1.0
• Right thruster : 0 - 1.0

/cmd_helm

Input :

• Thrust : Newtons
• Yaw rate : rad/s

/cmd_wrench

Input :

• Force vector
• Torque vector

/cmd_course

• Absolute yaw angle : radians : Doesn't work right now.
• Speed : 0 - 1.4 m/sec : Works but reliability is not confirmed.

IMU output topics

/imu/compass_heading

None

/imu/declination

None

/imu/raw_compass_heading

West = 0
North = 1.57
East = +/- 3.14
South = -1.57

/imu/data

Output :

• Orientation : Quaternion
• Angular velocities : rad/sec
• Linear acceleration : m/sec^2

/imu/rpy

Vectors x,y,z

Changes on reboot.

/imu/data_compass

Output :

• Angular Velocities
• Linear Acceleration

/imu/mag_calib

None

/imu/temperature

Temperature

Nodes information

/axis/axis /axis/axis_ptz /axis/teleop /axis_ptz/axis /axis_ptz/axis_ptz /axis_ptz/teleop /base_to_basefootprint_tf /controller - launched by controller.launch/base.launch /imu/declination_compute - launched by base.launch /imu_compass - launched by imu_compass.launch/base.launch /navsat/enu_from_fix - launched by base.launch /navsat/nmea_serial_node - launched by base.launch /navsat/nmea_topic_driver - launched by base.launch /navsat/upgrade/nmea_serial_node - launched by accessories.launch /navsat/upgrade/nmea_topic_driver - launched by accessories.launch /navsat_to_gps_tf /novatel/nmea_serial_node - launched by novatel.launch /novatel/nmea_topic_driver - launched by novatel.launch /robot_pose_ekf - launched by base.launch /robot_state_publisher /rosout /rosserial_message_info /rosserial_server /um6_driver - launched by base.launch /wifi_lights

Node [/um6_driver]

Publications:

• /imu/data [sensor_msgs/Imu]
• /imu/mag [geometry_msgs/Vector3Stamped]
• /imu/rpy [geometry_msgs/Vector3Stamped]
• /imu/temperature [std_msgs/Float32]
• /rosout [rosgraph_msgs/Log]

Subscriptions: None

Services:

• /imu/reset
• /um6_driver/get_loggers
• /um6_driver/set_logger_level

Node [/imu_compass]

Publications:

• /imu/compass_heading [std_msgs/Float32]
• /imu/data_compass [sensor_msgs/Imu]
• /imu/mag_calib [geometry_msgs/Vector3Stamped]
• /imu/raw_compass_heading [std_msgs/Float32]
• /rosout [rosgraph_msgs/Log]

Subscriptions:

• /imu/data [sensor_msgs/Imu]
• /imu/declination [std_msgs/Float32]
• /imu/mag [geometry_msgs/Vector3Stamped]
• /tf [tf2_msgs/TFMessage]
• /tf_static [tf2_msgs/TFMessage]

Services:

• /imu_compass/get_loggers
• /imu_compass/set_logger_level

---

Node [/controller]

Publications:

• /cmd_drive [heron_msgs/Drive]
• /eff_wrench [geometry_msgs/Wrench]
• /rosout [rosgraph_msgs/Log]
• /yaw_debug [geometry_msgs/Vector3]
• /yaw_rate_debug [geometry_msgs/Vector3]

Subscriptions:

• /cmd_course [unknown type]
• /cmd_helm [unknown type]
• /cmd_wrench [unknown type]
• /imu/data_compass [sensor_msgs/Imu]

Services:

• /controller/get_loggers
• /controller/set_logger_level

Sensing topics

/sense

• header:
  • seq: 0
  • stamp:
    • secs: 1558137306
    • nsecs: 721315248
  • frame_id: ''
• battery: 16.2778491974
• current_left: 0.0
• current_right: 0.0
• rc: 0
• rc_throttle: 0
• rc_rotation: 0
• rc_enable: 0

---

/status

• header:
  • seq: 0
  • stamp:
    • secs: 1558137379
    • nsecs: 811380195
  • frame_id: ''
• hardware_id: ''
• mcu_uptime:
  • secs: 2478
  • nsecs: 0
• connection_uptime:
  • secs: 2428
  • nsecs: 0
• pcb_temperature: 37.4632072449
• user_current: 0.0178504828364
• user_power_consumed: 9.27973747253
• motor_power_consumed: 1.96030080318
• total_power_consumed: 11.2400379181

---