CMM Ball Tip Compensation

Hi All,
Just re-visiting a subject from a few years ago to see if any progress has been made in this area.
Back then I did some CMM measuring, but had problems with the Ball Tip inaccurately recording metrics.
I needed a CMM Ball Tip Compensation app for Rhino.
Does anybody know if such a software add-on exists for Rhino?
I know others have it, but not sure about Rhino.

Hi Chris - all I know of is the document you are already familiar with -
I do not know of any app, myself.


Thanx Pascal.
Totally different process.
I’m talking about the ball tip being compensated in 3d space when it touches an object.
The surface of the ball is a given distance from the theoretical measuring point at the probe tip.
So that distance must be compensated for inside the data receiving software.
That’s what I’m referring to…

Check with the CMM manufacturer to determine if they have developed plugin that supports Rhino or other applications. It unlikely that any CAD application will support a specific device unless the hardware manufacturer has already provided a solution for the specific application.

Yeah, thanx.
I already know that.
Nobody is doing anything for Rhino.
Only SW and the big boys’ software.

Unfortunately its the hardware manufacturers responsibility to support their device.
If they don’t support it why would anyone else?

It’s just too bad there isn’t a standard that everybody uses so these things can easily be done by the 3rd party software people like McNeel. Gotta luv the way competition is used to screw the customer and extract coins out of them!

Hi Cadman,
unfortunately i cannot add any knowledge to your problem, but maybe you can help me out with my research on CMMs or similar hardware, can’t find a thread about hardware here?

What hardware are you guys using?
I am trying to find something i can read in grid points/curves of surfboards…so slightly bigger dimensions in the 2000x500x100mm range and glossy surfaces, any accuracy below 1mm is great, slightly more acceptable if absolute not relative…laser scanners seem too expensive and complicated, prodim proliner would be great but expensive and rather big, microscribe or similar would be great but also quite expensive and range is small so i would have to move scribe or object with overlapping areas for alignment…any idea for a cheaper higher range digitizing pen system? don’t need new, can be used…rhino integration would be preferred obviously…
I have a cnc so i could mount an arm on the gantry to increase range? would prefer beeing able to use it indipendently of the cnc but maybe that’s an option to consider?
Cheers, Andi

Hi Andi,

Sorry for the delay.
Haven’t needed to use Rhino forum for a while.

Far as inexpensive CMM or other input device, no such thing that I know of.
You may be able to buy a CMM you can mount to your CNC machine.
I’ve seen them, but they too are expensive.
You can program it to work its way across and down your surf board surface. and get section profiles.

If you want to ‘do it the hard way’, you can use cardboard cutouts at measured intervals to capture sections and then scan them into the computer using a large scanner. I’ve done that with vehicles. It’s a rough profile, but it usually is ‘good enough’. Note that it’s a lotta work doing it that way.

You can also use a combination of a small CMM and cardboard patterns. I’ve done that too. I have a Microscribe and it’s not ball-tip-compensated. Ball-tip-compensation is a very expensive software add-on or built-into the scanning software for brand-name CMM’s. But the Microscribe doesn’t have any, which is a major problem. So the Microscribe is very limited in its use, esp. if you want accuracy and have to drag a sharp point along a brand new vehicle’s paint job!

Also, Microscribe’s software is for SW not Rhino. You have to setup Rhino generically w/the Microscribe and then fiddle around with it to get it to work like you want. But the arm reach is short, like you said. The Faro or other brands with longer arms (like 8’ or 12’) that you can buy on eBay are WAY over-priced for their ancient age.

If you want to do a one-off, you can hire a service that uses Lidar and have them scan it for you.
Then you can bring the pointcloud into Rhinio or another processing software. The thing about Lidar is, you have to make sure the guy uses high resolution or you’ll get a ‘lean’ pointcloud. And if you have small details you need, you’ll miss them otherwise.

Also, having the scanned object in your possession is good b/c you can use it to QC the scan data and your 3d model.