HeadReferenceGoal
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Definition::

    # ====== DO NOT MODIFY! AUTOGENERATED FROM AN ACTION DEFINITION ======
    #goal definition
    byte LOOKAT = 0
    byte PAN_TILT = 1
    byte LOOKAT_AND_FREEZE = 2
    
    byte goal_type   # either LOOKAT or PAN_TILT
    
    uint8 priority 	 # [1-255] (action client calls with the same priority cancel each other)
    
    float64 pan_vel      # pan_vel
    float64 tilt_vel     # tilt_vel 
    
    # in case of LOOKAT:
    geometry_msgs/PointStamped target_point  # use in case of LOOKAT
    
    # in case of PAN_TILT
    float64 pan      # use in case of PAN_TILT
    float64 tilt     # use in case of PAN_TILT
    
    # timout
    float64 end_time  # goal cancels automatically after this time (seconds), if 0, no auto cancel