Recommended Procedure for Dry and Underwater Testing of Multiple Sonar Devices

Third Party Products Sonar and Acoustics
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1

Hello Blue Robotics community,

I am currently working on an ROV system and plan to use several acoustic sensors, including:

  • WaterLinked DVL A50
  • Ping Sonar
  • Ping360
  • M1200D multibeam sonar
  • Side-scan sonar
  • Other underwater acoustic sensors

I would like to ask for advice from users who have experience operating multiple sonar devices on an ROV.

1. Dry testing before deployment

For initial testing, I would like to verify that the devices can power on, communicate with the computer, and be detected by the corresponding software before putting them into the water.

Is it generally safe to power and communicate with these devices while they are completely out of the water?

Are there any devices that must not be operated in air, or that should only be powered for a short period during dry testing?

For example, I found a Blue Robotics forum discussion indicating that the Ping360 can be operated on a bench in air for testing, although the sonar measurements themselves may not be meaningful in air. (Blue Robotics Community Forums)

For the WaterLinked A50, I also found information that it has thermal protection, but continuous operation with the acoustic sensors enabled is preferably done underwater because the water provides cooling. (Blue Robotics Community Forums)

2. Powering the sensors before putting the ROV into the water

This is the part I am particularly unsure about.

If the ROV is powered by a battery inside the watertight enclosure, I assume the battery needs to be connected and the electronics powered before the ROV is submerged.

However, I am concerned about the correct procedure:

Should I:

  1. Connect the battery while the ROV is on the surface.
  2. Turn on the ROV and allow the computers/sonars to boot.
  3. Verify that all devices are detected and communicating.
  4. Then place the ROV into the water.

Or is there a recommended procedure where the sonar devices remain powered off until the ROV is already underwater?

I am particularly interested in the recommended procedure for the DVL A50, because it appears to have different thermal considerations compared with conventional imaging sonars.

3. What about the Ping360 and other sonars?

For the Ping360, I found that Blue Robotics users have successfully performed bench testing with a DC power supply before putting the sonar in water. (Blue Robotics Community Forums)

However, I would like to know whether there are any best practices regarding:

  • Powering the sonar before immersion
  • Starting the sonar before or after immersion
  • Operating continuously in air
  • Whether the transducer needs to be submerged before enabling acoustic transmission
  • Whether there is any risk of overheating during dry operation

4. Multiple sonar devices operating simultaneously

If an ROV has several acoustic sensors operating at the same time, such as:

DVL A50 + Ping Sonar + Ping360 + M1200D + Side-scan sonar

are there recommended procedures for powering them up and shutting them down?

I am also interested in whether there are potential issues with:

  • Acoustic interference between different sonars
  • Electrical noise
  • Power supply voltage/current transients
  • Ethernet/serial communication
  • Starting multiple sonars simultaneously

For example, I understand that the A50 can have a relatively high short-duration startup power requirement compared with its normal continuous consumption. (Blue Robotics Community Forums)

5. Recommended operating procedure

If anyone has experience with a similar ROV setup, I would really appreciate a practical procedure such as:

Before deployment → Power-on → Dry communication test → Enter water → Enable sonar → Operation → Recovery → Power-off

It would be especially useful to know which sensors can safely be tested in air and which ones should be submerged before continuous operation.

Thank you very much for any advice or recommendations!

2

Hi @trongtri -

I’m familiar with the devices you list, except for the M1200D multibeam sonar. They are all powered up when battery power is connected, and are not going to damage themself in air. The DVL will warn you if temperature becomes an issue, assuming you’re connected to the vehicle via GCS (Cockpit or QGround Control.)

Because all the sonars you list use different sound frequencies, they shouldn’t interfere with you. However I’ve seen artifacts from a similar DVL when running the Ping360, these are fairly minor.

I assume your side scan sonar is the Cerulean Omniscan FS?

Please follow the integration guides, found on the respective product pages, to ensure proper setup. You may find the default ROV does not have sufficient available penetrators for all those sonars! In addition, some redundancy may be present - the DVL provides altitude measurements, so mounting your ping sonar pointing downwards would be redundant.

The ROV operations guide confirms that powering the system prior to launch is the normal approach!

Individual power control of each sonar would require significant additional switching components!

3

The Oculus imaging sonars (like the M1200d) can be safely run in air. Like the other sonar types, if left pinging in air they will eventually overheat and stop automatically.

Note it will only ping when a client program (like Oculus Viewpoint) is connected. If no software is talking to the sonar, it will be idle.

On a separate note, I would build a table of the ping rates and frequencies of all of your acoustic devices to check for interference. You may find that some of the devices cannot be used at the same time, or you may need to look into a synchronization method to ensure they don’t ping at the same time.