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Ping Viewer Error Propagation Issue

Hi all,

Has anyone had any issues with the ping sonar propagating error in such a way that the data graph takes on a sawtooth look?

The problem I’m having is that I will get an initially good read, but then the reported value will steadily increase (with a corresponding decrease in confidence) until it peaks and shoots back to the original close to correct value before repeating the cycle. It’s a little difficult to describe, hence the screenshot.

The test setup was a BlueROV2 on a table balanced (on the angles of the frame where the corners would be) looking down towards the floor, with speed of sound corrected to 343 m/s for bench accuracy testing. Actual distance to floor is 1.5~2m. FW is 3.26.

If you have any tips for me or need any info from me, please let me know. I’m new to using the ping sensor, so any help is appreciated.

Edit: I’m using this for obstacle avoidance so it’s forward mounted, not set up as an altimeter.

Try it in water, the sensor is not designed to work in air. What you are seeing is the sensor auto-ranging while it looks for the target, this is normal and expected (in air).

@jwalser,

Thanks for the quick response, I appreciate the help.

That’s a good point, I didn’t think the auto-ranging would function like that but it makes sense now. Glad it’s me doing things incorrectly, 'cause that’s easier to fix.

For anyone else with this issue whose UUV isn’t assembled enough for wet tests, I managed to get a 100% conf reading by placing the sensor directly in front of a wall. Any sort of deviation, like an angled floor, will trip up Ping’s auto-ranging and give you incorrect data.

Hi All,
I am using BlueRobotics Ping sensor, Previously it used to give me correct values in water almost 90% accuracy and 100% confidence for most of the time when it is in water, but today while using it in water itself I found that it is not reaching to 100% confidence and even rarely it is touching above 80% and that too as an impulse. I changed the firmware and tried with both 9600 and 115200 firmware versions but still no positive response I am getting in this.
Please help me to rectify the problem & can please tell me the reason of this as well.
Thanks in advance

Hi Abdul,

What is your test environment ? Make sure to respect sensor min and max range distances.
Besides that, are you running in auto mode ?
image

Make sure that Auto Gain is selected, from our documentation:

Enable automatic gain and range adjustments (ENABLED is the recommended default settings).

Hello Patrick,
Yes I am using Auto gain only

Hi Absul,

Please, as asked in my last comment, can you describe your test environment with the dimensions.
Can you share the log of your last attempt ?
Both sensor and interface.

Hi Patrik, Sorry I missed your message.
Yes, I am testing my ping sensor in a water tub of 200(L) x 100(B) X 50(H) and in that, I don’t test the sensor perpendicular to the ground but parallel, because its minimum range is 50cm, I tested it yesterday after 10-12 days and found that if I keep my sensor in the mid-layer of water then it is giving 100% confidence but when no gap between the bottom layer of our tub and ping sensor (but not perpendicular) it doesn’t give me 100% at all. So think if we have to mesure the depth of a well or pond then the sensor should not be attached to any of the wall. As its has the beamwidth of 30degrees so it may collide with the walls of tub, well, pond etc.