# Reports position of drone, payload, and the roll angle between them
std_msgs/Header header		# Header
string drone_id			# Drone ID
geometry_msgs/Pose drone_pos	# Drone pose
# sensor_msgs/Imu drone_acc	# Drone linear acceleration
string pload_id			# Payload ID
geometry_msgs/Pose pload_pos	# Payload pose
float32 length			# Tether length
float32 phi			# Roll angle between drone and pload
float32 phidot			# Roll rate
float32 theta			# Pitch angle between drone and pload
float32 thetadot		# Pitch rate