Lidar Lite v3 Irratic Measurement

You could be getting reflections from more distant objects that are appearing in the next distance cycle.

It depends upon the AGC they use and the chirp encoding.

Given the price of the unit, I would expect it to have just minimal interference circuitry built in, so you will expect to see some erratic behavior.

Is there a highly reflective target in the far field?

Different reflectivity can introduce errors.

DAB

Is it possible it is seeing some dust? You could try sprinkling some dust in the beam to see how much it takes to start getting erroneous data.

Hi Bruce

Mine does exactly the same, I think Douglas and DAB have it thouh.

You can try setting the different modes for short/mid/long range to make it a bit more accurate.

In the end I started taking 3 measurements and taking an average of the closest 2 results. Increases the scan time though so its not really ideal but it smooths things out a bit

Will check to see how to control the ranges unless you post it here first.  :0

Thank you so very much!  Will have to remember this when I get it into a real working environment.

Here is the document that I am using:  https://static.garmin.com/pumac/LIDAR_Lite_v3_Operation_Manual_and_Technical_Specifications.pdf

Is it the same document that you are using?

Apparently I am overlooking the close, mid and long range setting if it is.

Thanks,

Bruce

Hi Bruce

Im using the LIDARLite  Arduino Library. It gives you options for config and scanning.

When you call the distance method there is also a true/false parameter to scan with or without bias correction. Its recommended to run this every 100 scans or so

https://github.com/garmin/LIDARLite_v3_Arduino_Library/archive/master.zip

  Parameters

  ------------------------------------------------------------------------------

  configuration:  Default 0.

    0: Default mode, balanced performance.

    1: Short range, high speed. Uses 0x1d maximum acquisition count.

    2: Default range, higher speed short range. Turns on quick termination

        detection for faster measurements at short range (with decreased

        accuracy)

    3: Maximum range. Uses 0xff maximum acquisition count.

    4: High sensitivity detection. Overrides default valid measurement detection

        algorithm, and uses a threshold value for high sensitivity and noise.

    5: Low sensitivity detection. Overrides default valid measurement detection

        algorithm, and uses a threshold value for low sensitivity and noise.

  lidarliteAddress: Default 0x62. Fill in new address here if changed. See

    operating manual for instructions.

Hope this helps! Any questions please dont hesitate to ask

Matt

That information isn't in the Python library.

Thank you so much!

Every 100 scans or so, am I to run read with what option?  W/o bias correction?

I have translated the CPP configuration method to Python.

Nice work!

Its on by default, so you can run the method sending false as an argument, then every 100 add a true in there

Looking at the comments on the method from the .cpp file

  ------------------------------------------------------------------------------

  biasCorrection: Default true. Take aquisition with receiver bias

    correction. If set to false measurements will be faster. Receiver bias

    correction must be performed periodically. (e.g. 1 out of every 100

    readings).

Are you doing point clouds with your scanner?