Ultrasonic Phased Array Display - anyone done this in LabVIEW?

[DonRoth]

As I mentioned in an earlier post, I am sure there is a clever way to do this directly with the LabVIEW Intensity Graph.  Yes, knowing magnitude, phase, and intensity, we should be able to convert this to X (real), Y (Imaginary) and intensity for intensity graph.  I first wanted to pursue this using the LabVIEW existing plot types and the polar plot or compass plot appeared to be at least good places to start.

If you can use the setpixelvalue for the Vision container, we should be able to take a reasonably similar approach with the intensity graph by just replacing the initial background values with the new intensity value at the correct X (real) and Y (imaginary) values on the intensity graph.  So below is my initial attempt to do that. I have specified a phase angle of 10 deg.  The intensity graph line seems steeper than this.

....Don

[DonRoth]

...problem was phase angle needs to be in radians....Don

[DonRoth]

This one has a few updates after a some more time to play today.  Plotting multiple lines, converting from picture control to intensity graph demo, etc.  Converting from picture control to intensity graph demo works for gray scale.  I have never figured out the correct way to get that to work for a non-gray scale color table using the 24-bit pixmap for the picture control.

As discussed earlier, there are gaps between the lines.  Not yet sure of strategy to average, possibly drawing the lines in a much denser fashion than with 1 deg increments.

Don

Message Edited by DonRoth on 05-25-2010 08:57 AM

[DonRoth]

If we plot 500 lines (versus 50 in the example above), each separated by 0.1 deg (versus 1 deg in the example above), here is what we get (just showing the direct intensity graph plot).  0.1 deg seems about right.  At 0.2 deg, you will see a few gaps towards the outer edges.

Message Edited by DonRoth on 05-25-2010 09:15 AM

[DonRoth]

Hi folks -

Getting back to this problem today.  Have made more progress on this with actual data.  However, I am wondering if there is a geometrical transformation using the intensity graph that will allow me to shift the starting locations of the lines to account for the fact that ultrasound has finite beam width.  The starting points need to "fan out" slightly, with the rest of the line proportionally fanning out while keeping the end points where they area.

I tried to embed images here to show what I am after but got 10,000 characters exceeded so am just attaching images.

Note at the top left corner of one image, there is a finite beam width near 0,0.  The lines do not all meet at 0,0.  So again, the line starting points need to be shifted slightly while keeping the end points the same.  I know the distance of the maximum shift, and think the shift of all starting points would be proportionally reduced from the max down to 0 to achieve this effect. But the rest of the points in each row have to be shifted as well to effect the geometrical transformation. But, again, I am stumped on how to implement this for the 2-d array of the image, row by row. 

ps. Not worried about the x, y scaling difference between the images - I adjust intensity graph scale range maximum to get the images to look the same.

Message Edited by DonRoth on 06-14-2010 08:32 AM

[Deon]

Hi DonRoth

Did you ever complete your Ultrasonic Phased Array Display code?

I am just starting work on such a project and need to display a Sectorial Scan from an array of Ascan plots with scan angle and offset data. I've had a look at your code and as you imply you still need a way to plot the non-zero origins and also the line width needs to be increased proportionally as the Ascan waveform fans out, in order to provide more visual information.

Any help would be appreciated.

Many thanks

Deon

[MarcDub]

The HaroUT library will include a Sectorial scan (S-scan) feature (as demonstrated in this document and video.) The HaroUT library will also include programmatic access to the HaroUT calculator and to some hardware. Do not hesitate to contact me with questions, suggestions, or feedbacks.

[Deon]

Hi Marc

Thanks for your reply. 

I'll download your app and let you know how I get on .

Regards Deon 

[Deon]

Hi Don

I've used the intensity graph and managed to implement the phase corrections and offsets. This is an image from a steel block with five side drilled offset holes at different depths.

Regards Deon

[DonRothGE]

Great to see progress after all these years!  I do still use LabVIEW to write small utilties in my present role with Baker Hughes, but I have not done anymore work on the NDE Wave & Image Processor since I left NASA in 2014.  I cannot recall where I left off with the PAUT display.  Good luck to everyone.

Sincerely,

Don