Alignment Methods

[[Ja...]]

Hi all

I know on other CMM's we have set up alignments which instruct the operator to move the probe to the centre of the part, press okay - the machine then pulls the XYZ position from the system, and from that we create a theoretical point, origin XYZ, creating an initial 'datum'. The machine then goes into CNC mode and measures the plane, circle etc relative to that initial 'theoretical point'. So all the operator is doing is moving the probe into position and hitting okay. 

I've been setting up Autorun and considering altering alignments in the main programs to make aligning as 'simple' as possible for a inexperienced operator.

Can the method I've written above be replicated in Calypso?

[[Cl...]]

If the fixture is in the same location on the CMM all the time and is also Poke Yoke.

You can perform the initial Start Alignment which tells Calypso were the workpiece

is within the CMM's volume. I usually do this on the fixture itself. Once this is done.

From "Run Measurement Plan" Tick "Base Alignment", Then from the drop-down menu

just below that chose the Base Alignment you wish to run. The software knows the

part/fixture location and the performs the Base Alignment, which I would loop as well.

[[Ma...]]

I would rather spend time to make better fixture, or teach operators.

Surelly you can try, but i think you will hit safety wall with clearance cube.

What you can do is let operators to touch that point manually, then move probe to safe location and hit continue.

[[Da...]]

My experience with "read-point alignments" like this is that they only work easily on an already-aligned inspection fixture. Anything you expect the operator to set up and "tram-in" manually will have a good bit of uncertainty, so you will need very large margins when checking your line and point locations for the machine alignment.

[[Je...]]

I appreciate the feedback on best-practice for locating a workpiece.

However, let's keep in mind that

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 asked if the "manually move to center of part and click 'okay'" method is possible in Calypso.

Jack, yes, this is possible in Calypso as well.  As the others have hinted, this occurs through using what is called a "start alignment," which is a simplified version of the base alignment.  The base alignment then runs (usually in CNC mode) after the start alignment is computed.

[[Ni...]]

We use a 'start' alignment, which we set as a single point. We manually hit the part for the single point and then the program goes into CNC mode and takes the appropriate 'base alignment' features. The only requirement is getting the part 'fairly' square how the part is set up in the virtual space as well as taking the hit point in the correct spot on the physical part as compared to the CAD model.

We set up 99.9% of our programs this way.

[[Ja...]]

Thanks gents; 

So

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 are you saying a simple 'point' is sufficient enough for the machine to go into CNC mode, and have enough information to measure? No plane, origin etc is needed to lock XYZ rotation/translation directions?

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 thanks, we do use start alignments however it still involves manual point taking of planes/circles etc. Can calypso pull machine variables from the software of XYZ locations of where the probe is on the bed? So in theory if I position my probe at the centre of a part, pull in the positions, create a theoretical point based on those positions, set my 'start alignment' on that point. The software has enough information to be able to go into CNC and measure. Hope this makes sense. 

Appreciate all the responses so far.

[[Ma...]]

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 If machine will perform that point touch without problems, then you can create theoretical plane/s to fill primary and secondary datum, origin can cover that point.

I am using this method if i have only secondary. This way it should take from machine alignment.

Or if you want to be sure then make a program which will be used as loaded alignment to have assured axis directions ( aka primary - secondary / rotation in space and the other one )

[[Je...]]

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, yes that is possible but I can't articulate the steps, since I haven't had to do that specific task.

The process you described is similar to how a base alignment is computed, with the difference being that in your method the origin is defined by the center of the probe rather than computed from measured features.

The button labeled "special" in the alignment window may allow that type of an offset to be defined based on a parameter.

My perception is that the reason you would attempt this is either to simplify things for your operators or create an ultra-fast universal workflow for yourself.

I applaud the experimentation and innovation.  However, I do feel that the needs you may be trying to address (without knowing specifics) are fully satisfied by Calypso's built-in alignment process, perhaps with a bit of customization embedded in a template measurement plan.

I'd love to hear more about your thought process and how this project evolves for you.

[[Cl...]]

In a production environment, this whole issue goes away if fixed interchangeable part

specific Poke Yoke fixturing is implemented. Unless of course you work in a job shop 

[[Ni...]]

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Correct - a single point can often (or almost always) be enough information for the machine to know where to go for all of the base alignment features. If you consider just a basic square part, the part needs to be set up on the CMM in the same orientation (does not need to be exact, just close enough that your probe doesn't miss, for example if you're alignment hits are only .050" from an edge, then the part needs to be square within .050")

I follow the steps shown below (Drop your single "start" point on the model.) In your alignment area select "use start alignment." In the start alignment itself put that point as your X/Y/Z origin.

 

When starting the CNC run simply select "start alignment" instead of "base alignment." The CMM will prompt you to take the single point and show you where it needs to be taken it. 

 

 

 

 

 

[[To...]]

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Here's a tip.  In the Start Alignment window, tick the "Manual Alignment" option.  In the Start Measurement window, when you select the Start Alignment option, it will automatically select Manual Alignment so you don't have to remember to choose it.

[[Dy...]]

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Hi Clarke,

Let's say after the initial Start Alignment was created in "Program 1", but the next day an operator has a part that requires removal of the fixture plate. Is there any way to run a Manual Alignment of the Start Alignment through any of the other programs EXCEPT "Program 1"? In other words, if i open "Program 5", that is using the same Start Alignment that was created in "Program 1", go to the Run Screen, and choose Start Alignment>Manual Alignment, can i actually run that Start Alignment Manually, or am I forced to return to "Program 1" to manually re-align the fixture plate? No matter what i select in the run screen of any other program OTHER THAN program 1, Calypso skips over the Manual Alignment and goes directly to the base alignment. 

Also, just a few more questions, could you give me a brief run down of YOUR method to Load the Start Alignment in "Program 2"?

While creating "Programs 2-5", should i be able to see the features in the Start Alignment window, from "Program 1" or are they loaded in the background?

Do i have to Extract those same features in "Programs 2-5"?

After loading "Start Alignment" in "Program 2", and then returning to "Change Current Start Alignment", should i be seeing those Extracted Features from "Program 1" populating those fields? 


Thanks in advance!!!
 

[[Cl...]]

To answer the first part of your question. I'm not talking about using one SA for all my programs.

Each and every program has its own Start Alignment. After the start alignment and base alignment

have been done for a program which is located on a dedicated fixture, which is always in exact same

spot on the CMM. The Start alignment XYZ location in MCS is stored. As well as the XYZ offset between

the SA & BA. No SA is needed to run a program because Calypso has stored it's location which never

changes. Stylus goes and probes the BA features. 

[[Je...]]

Hi

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  Great questions.

Your post is bringing something into focus for me, which is a pattern I’ve noticed when talking with other programmers, especially those coming from PC-DMIS or other step-based software. There seem to be two major approaches to locating a workpiece:

1. Align to a universal zero point within the machine volume (like a corner block or fixture plate), then apply offsets to the part. This is almost like if you had an automated claw machine that picked up parts on an assembly line at the same spot, so you move the workpiece to that pick-up point.

or

2. Align directly to features on the workpiece itself.

Calypso is fundamentally designed around the second method. In my experience, that native, feature-based workflow is significantly better in terms of precision and repeatability, especially when you’re dealing with intricate geometry or parts that naturally vary, like molded or cast components.

That’s more of a sidebar, but it’s relevant.

To your main point: I often copy features and alignments from one plan to another when feasible. After that, I’ll often use CAD > CAD Comparison to reconnect features to the model.

Even better, if I’m making a new plan based on a prior one, I’ll use Save As to template the first program for the second. Then, I delete features not-of-interest before programming for the new features. While this will allow you to use the same alignment, I never do because it would create the risk of one program changing the alignment's actuals without the other knowing.

Instead, I either copy the base and start alignment or make new but identical alignments.

Then—and this part is important—I go into CNC > Pre-assign CNC Start Values and use the drop-down menu to select the correct Alignment, which will be one spot up on this menu from the previous alignment.

Let me know how your process evolves. I think this topic is really valuable, and I’d be curious to hear where it leads you. There are storied chapters of this forum's history on alignment discussions, because they're so important.

[[Dy...]]

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Jeff,

Thanks again for that explanation! I’ve struggled a bit with understanding how Calypso handles the saved “Work Area” versus a normal CAD model. Initially, I avoided using this feature because I wasn’t sure (and honestly, I’m still not 100% sure) whether models saved under “Work Area” would be viewable in the normal CMM environment. My assumption has been that anything saved under the “Work Area” option wouldn’t be accessible anywhere outside of Planner/Simulation, which is why I hesitated to set it up this way from the start.

That said, I realize I’m in a bit of a unique situation. I work mostly remotely, and our HQ is on the other side of the world! Currently, I handle everything related to Quality and Engineering—editing and creating CAD files, blueprints, inspection plans, and so on. Our U.S. division is extremely small, so I have full flexibility to set things up however I see fit—but I am working against a hard deadline. All programs, prints, inspection plans, and AutoRun setups need to be completed by the end of September 2025, so I don’t have a ton of extra time given the workload.

After a crash course in SolidWorks, I began creating the first parts for our new production line and decided to create a template SolidWorks Assembly that includes all of the fixturing I’ll ever need. As I create each new part, I mate it to the fixture and export an .ACIS file of the entire assembly for Calypso.

Fortunately, I got a call last week from a Senior Zeiss Application Tech Engineer, who walked me through the correct way to use the same Start Alignment throughout this project, along with how to use the “Move” and “Compute” options tied to this method.

If I understand your process correctly, it sounds like you import your fixture models into the “Work Area,” create some alignment there, and save the “Work Area.” Then you import the CAD model of the part to inspect (as normal) and use CAD Transformation to position that part model relative to the fixture model saved in the “Work Area.”

Is that more or less correct?

If not, could you explain a bit more about Point 1—specifically this part:
1. “Align to a universal zero point within the machine volume.”
How exactly would I go about selecting a feature within the machine volume for this? I’ve assumed I was already doing this by using the fixture plate for my Start Alignment, since it never moves.

If this is where I’ve been missing a step, it might explain a lot. By skipping this—or possibly setting it up incorrectly by combining the inspection part and fixture together—I’ve noticed that my CAD keeps snapping back to the home position after I save any changes. Basically, after I load my CAD model (which contains both the part and fixture), position it using the “Point” function under “Positioning” in the Measurement Plan Simulation > Modify CAD Entities window, then hit “Save” or “Save As,” the model shifts back to the home origin as soon as I re-open that window or try to view the Simulation again. I’ve been manually re-positioning it each time, but surely there’s a way to lock the position permanently after the initial setup?

I’ve attached a couple of screenshots that may help show what’s happening.

Thanks again for taking the time to explain all this, Jeff!

Also, if you don’t mind, could you link me to those forum libraries you mentioned regarding Alignments?

TIA!

 

[[Je...]]

Hi

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You have a very interesting and dynamic role with your company.  Thanks for sharing about it.  The flexibility you described sounds incredibly important, especially when considering the tight deadline you are working towards.

Great job on reaching out to the experts at Zeiss.  The Application Specialists at Zeiss a powerful (and friendly) resource who have helped develop my career.  They've resolved countless metrology headaches, and they've been like a Rosetta Stone in helping me understand alignments.

First off, thanks for explaining that you are programming 100% offline via Planner.  That informs the process.

The behavior you are noticing of the CAD models populating to the machine's home position is normal.  Calypso will do this until a manual run is performed, which repositions the origin.  Fortunately, this manual run can be accomplished in Planner (simulated manual run).

However, most programmers will move the CAD model within the machine's work volume via the "Modify CAD entities" or "CAD transformation" windows before performing a manual run.  I prefer the "Modify CAD entities" window, because it provides more control and functionality than the "CAD transformation" window, which is a bit oversimplified.

The rotation of the CAD model is the critical aspect.  Position can always be offset, but if the rotation of the CAD model is inverted from how the workpiece will normally be oriented, it can be difficult to impossible to resolve.

I have a meeting in a few minutes, so I'll have to head out for now, but I'll DM you my contact info.  You're welcome to reach out if you'd like more help.  I'd be happy to schedule a Teams call with you sometime to walk through best practices for alignments.  If your company has a ZeissCare agreement, keep utilizing their support line and the application specialists to answer your questions.  Zeiss provides the best aftermarket metrology support on the planet.  There are plenty of times when I have scheduled follow-up calls to previous tickets with a new ticket to help reach the finish line with ongoing challenges.

You're doing great.  The Calypso workflow and alignment "whole picture" will become increasingly clear through practice.

Lastly, an older mentor once gave me a great piece of advice for when CMM frustration boils over: stand up, walk away from the computer and visit the vending machine 🤣 (or healthier outlet).  Sometimes resetting the next day can bring renewed mental focus and success.

 

Edited July 9