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Tracker 650
Tracker 650
  • Overview
    • CERULEANTRACKER DEPRECATION NOTICE
  • Quick Start for BlueROV / ArduSub Users
  • General Specifications
  • Configuring the Tracker 650
    • Finding the Configuration Web Page
    • Example Configuration Web Page
    • Live Status Page
    • Setting the Static IP Address
    • Setting the Fallback IP Address
    • Setting the Host IP Address
    • Setting the MAVLink REST Server Parameters
    • Setting Pool Mode
    • Setting DVL Mounting Rotation Offsets
      • Scenario: Driving Your Own Kalman Filter
        • Forward-Facing Mount
    • Setting Velocity Adjustment
  • General Usage
    • General Hints and Tips
    • Basic Operating Guidelines and Hints
    • Setting Speed of Sound
    • Scenario: Doing Your Own Dead Reckoning
    • Scenario: Holding Position
  • Using MAVLink and BlueOS for Position Hold on a BlueROV2
    • ArduPilot Parameters
    • Tracker 650 Setup for MAVLink Support
    • Global Origin
  • Mounting the Tracker 650
    • Bottom Mount
    • Thruster Deck Mount
      • Send xxx Message
  • Mounting Drawings (V1 pre-2025)
  • Communicating with the Tracker 650
    • Factory Defaults and Default Messages
    • The Ethernet Interface
    • Tips on How to Find the IP Address Assigned to Your Ethernet Adapter
    • Outgoing Message Formats, Tracker 650 to Host
      • $DVPDL and $DVPDX: DVL Position and Angle Deltas Messages
      • $DVNVM Non-Volatile Memory and Configuration
      • Freeform Error and Informational messages ($DVTXT)
      • $DVKFC Kalman Filter Raw Data Support Message
    • Commands Accepted by the Tracker 650
      • CONFIGURATION
      • SET-VELOCITY-ADJUSTMENT
        • SET-SPEED-OF-SOUND
      • SEND-DVPDL
      • SEND-DVPDX
      • SEND-DVKFC
      • SEND-MAVLINK-DISTANCE
      • MAVLINK-ORIGIN
      • SET-POSITION
      • SET-SENSOR-ORIENTATION
      • IP-ADDRESS
      • HOST-ADDRESS
      • MAVLINK-ADDRESS
      • FALLBACK-ADDRESS
      • UNICAST-TO-ME
      • PAUSE
      • RESUME
      • REBOOT
      • SET-POOL-MODE
    • Blue Robotics Discovery Protocol (Ethernet Only)
    • ARP (Address Resolution Protocol)
    • DHCP (Dynamic Host Configuration Protocol)
    • Ping (Internet Control Message Protocol Ping)
  • Coordinate Systems
  • Mounting Drawings (V2 post-2024)
  • CAD Models
  • Electrical Drawings
    • Power and Ethernet Cabling
  • Expectations
  • Copyright
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  1. General Usage

General Hints and Tips

PreviousGeneral UsageNextBasic Operating Guidelines and Hints

Last updated 2 months ago

  • Ocean/lake bottom and water conditions such as salinity affect the maximum altitude at which you can operate reliably. When the maximum altitude is exceeded the Tracker 650 sends data messages with confidences set to 0.

  • Accuracy of the Tracker 650 reduces as you approach the minimum standoff (altitude), starting at about 1 meter standoff.

  • If possible the Tracker 650 should not be operated below its minimum altitude. It does not always detect going under minimum altitude and multiple reflections between the ROV and the target plane can appear to the Tracker 650 to be valid target plane detection and introduce spurious motion estimates. If you drop under the minimum altitude, try to hop up to at least 2 meters above the target plane to allow the Tracker 650 to re-acquire. In a muck environment, crashing into the muck can entrain gas bubbles and particles in the thruster wash, which may be interpreted by the Tracker 650 as sudden shifts in speed. The message contains an estimate of standoff so you can watch as you approach the minimum. The standoff data can optionally also be sent to the and act as a virtual sounder.

  • If the Tracker 650 is not parallel to the target plane when it is moving, some of the X-Y velocity will end up in the Z velocity. For example, if you are driving your ROV parallel to a flat seabed at one meter per second, and the Tracker 650 central axis is pointed at 80 degrees down from the X axis (90 degrees would be needed to make the Tracker 650 parallel to the seabed), then the X velocity would read as 0.98 m/s, and the Z velocity would read as -0.17 m/s. If you a using a good IMU (and the orientation between the IMU frame and the Tracker 650 frame are known) and are integrating the delta positions in three dimensions, this will all work out as expected. If you are dead-reckoning only in the horizontal plane (or other plane parallel to the target plane), you can use the command to fudge in a correction factor.

  • If you are sitting at the surface and using active control to keep the ROV partially out of the water, be aware that air bubbles may become entrained in the thruster wash and cause false target plane and false motion detection.

  • The Tracker 650 sometimes does not perform well in pools due to reverberations, which causes constructive and destructive interference with reflections which confuses the bottom tracker. For pool usage you can try.

  • When using the Tracker 650 for position hold in areas with heavy vegetation, it is possible to get into a positive feedback loop that introduces error. If the ROV is directly over vegetation, the ROV thruster wash can cause the vegetation to move away from the ROV. This motion is picked up by the Tracker 650, and the ROV can respond by traveling in the direction of the vegetation motion. This can put the Tracker 650 over previously undisturbed vegetation, and the process repeats.

  • DVL velocities are noisier than you would expect (see ), but surprisingly, by integrating over a short span of time they quickly regress to the mean.

  • See the SonarView docc or the for how to install firmware updates.

$DVPDX
MAVlink interface
SET-VELOCITY-ADJUSTMENT
pool mode
here
CeruleanTracker docs