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Trying to set up relational table

pimm
14-Alexandrite

Trying to set up relational table

I've never used Relation Tables before but I see where this might be quite helpful.

So far the only thing I've figured out is how to put in a text description in what I'd like the table to do.

I have a number of sections that I've made into a Swept Blend feature.

These sections need a modified draft value for the side walls.

For every section that I have (There are 14 total) I would like to increase the sidewall angle by 1 degree.

Since each section has 4 sidewall draft dimensions I will need 56 dimensions updated to increase the draft value by 1 degree.

I know that each dimension in the sections has a different symbolic name. Most of the dimensional values are different.

I'm thinking that I would have to modify the symbolic names so they include something in common, so the draft value will be changed in each of the 56 dimensions.

How would the relation table values appear for something like this?

To give you a better grasp of what I am working on I'll attach a snapshot of a few of the sections.

Sections.JPG



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35 REPLIES 35
pimm
14-Alexandrite
(To:pimm)

I've made another simple series of sketches just in case it might help by setting up a simpler relation table. I can place this on the net if it would help.

SketchesWithDraftWalls.JPG

I'm thinking that I would like to tie all the sidewall features to a single draft feature from the 1st sketch. If I add a degree of draft to this single feature I'd like it to update the remaining sidewall drafts in the sketches by the same offset value.

John.Pryal
12-Amethyst
(To:pimm)

Hi Paul, maybe you are over complicating things here. Why so many sections? Maybe i am not fully understanding your finished geometry, so apologies if i am not. If i am understanding things right, i would have thought 2 sections, one at each end of the sweep would suffice, with a simple relation controlling the draft angle of sketch 2. If indeed you do need all 14 sections in your sweep, you certainly don't need 56 dimensions adding to the table, each sketch would only require 1 dimension. You need to create 'equal' constraints within the the sketch itself. Take your sketch 1, d26, d27, d28 & d29, i assume have the same value, in sketcher make then all equal, you only need change 1 dimension to manage the others.Then your relation might look something like d38=d26+1, d48=d26+2 & so on.

Hopefully this helps you out.

Regards

John

pimm
14-Alexandrite
(To:John.Pryal)

John,

I appreciate your reply to this confusing topic.

Unfortunately I think I over simplified the 2nd sketch set that I attached just to show a simple example. There might be an angle or 2 that happen to be the same draft but as a rule all the draft angles in the sketches are different values.

Based off your reply I should be able to control all the angles but it would require writing 55 different sets of equations based off of the original draft that 1 degree was added.

I will try this inside of my simple model with sketches.

I am wondering whether you could rename these 55 draft features to a common name that would add 1 degree of draft to each of these with only 1 equation line?

John.Pryal
12-Amethyst
(To:pimm)

‌Ok, what about a different approach. Instead of writing 56 different relations, how about using Table Pattern. Pattern sketch 1 to create 13 more sketches, adding the 4 draft side angles to the table. It would certainly be quicker. Just a thought.

John

pimm
14-Alexandrite
(To:John.Pryal)

I don't believe this would work in our application because there are varying widths, twists, depth tilts inside sketch, and tilted datums to line up. I've only shown the simple portion of our part.

I didn't even realize there was such a thing as a pattern table. That sounds like a great feature.

John.Pryal
12-Amethyst
(To:pimm)

‌Table pattern is one of my favourite creo features, very powerful. You can add multiple values to the table, as well as pattern multiple features grouped together. Don't write it off just yet, it could be a possible solution. All the things you mentioned, could in theory be added to a table pattern. Good luck.

John

Patriot_1776
22-Sapphire II
(To:pimm)

Is it stepped, or a smooth blend? If stepped, that would explain 55 different draft features! If it's smooth, why not use a VSS (Variable Section Sweep)? You can use a graph feature to specify a changing angle.

pimm
14-Alexandrite
(To:Patriot_1776)

Frank: Most of the models that I make I go with the VSS because it does a good job with matching up side walls.

With this job the customer left all of their section curves in the model so I could make my blocker stage of the model directly off of an exact replica of their model.

I have heard that it was possible to modify numerous dimensions based off of 1 driving dimension, with this I saw an opportunity for learning how this technique would be done.

In the future I would like to inquire how you can specify adding draft with a graph feature.

With this job I'd like to follow the pattern that was established by our customer. The model itself has replicated well. Adding draft however is posing a challenge.

Unless there is another quick way of adding a degree to each draft feature I am thinking I might punt and make this into a large family table model. With this I can bump up each column dimension by one.

John: I did try the formula you suggested but I would have to tweak the original value to replicate some very odd values +1 for a lot of features.

Patriot_1776
22-Sapphire II
(To:pimm)

Well, the thing with a VSS is that the other trajectories needto not have any steps normal to the origin trajectories. There can be an angle and they need not be tangent, but the step can't be normal. Or, if you want to vary it smoothly, put the angle dimension in the graph, and reference the graph in the VSS section relations.

John.Pryal
12-Amethyst
(To:pimm)

Paul Imm wrote:

I have heard that it was possible to modify numerous dimensions based off of 1 driving dimension, with this I saw an opportunity for learning how this technique would be done.

‌I think this driving dimension would be in essence, a parameter.

John

Good to mention - users lose track that it's primarily a parametric modeler. Each dimension is parameter as are the tolerances. They all have names and values.

The OP could create a set of relations that drive each dimension from an independent parameter; if the names were edited the relations would be easy to validate.

I'm confused by the term Relation Tables, as I've not heard of them mentioned that way before. They aren't really tabulated, just a list.

pimm
14-Alexandrite
(To:dschenken)

David,

The OP could create a set of relations that drive each dimension from an independent parameter; if the names were edited the relations would be easy to validate.

This is what I am trying to do. I just don't understand how this is done. What I'm looking to do is increase the draft angle 1 degree. (If the draft is 6 it would become 7, if it was 20 it would become 21 and on down the line) I have given each of these features an independent name to be able to understand which section that it is from.

I named them so I could better understand where each of them placed within the mile long family table which I finally decided to use. By the way I was surprised to find that the family table I built actually accomplished what I was looking to do.

I still have to believe that the simplest way to get what I want would be to set up relations. I'm hoping that someone could describe what this formula would need to be.

Sorry I mis-labeled Relations as Relation Table. Since there was a box in which you fill in your needed formula I thought it was a table.

John.Pryal
12-Amethyst
(To:pimm)

Paul, did you know that you can write relations within sketcher? You have 14 sections, that's 14 sketches that could have 4 relations written within the sketch. I not sure this helps your situation, but it would make things more manageable. I don't see a way of achieving your goal other than writing 56 relations, I would loved to be proved wrong.

John

pimm
14-Alexandrite
(To:John.Pryal)

John,

Thanks for bringing that up. That would be great if you can at least cut down the amount of items needed in the family table to 1 value for each section.

In going through all the sections (as per your suggestion) I was able to reduce the amount of family table features to 40 by using the Equal constraint with the draft angles that were identical.

I'll see about tying the parametrics within each sketch together. If this works it should reduce the Family Tree items to 14 (1 per each section).

I too am crossing my fingers that there is a way to tie it all together with just 1 entry.

John.Pryal
12-Amethyst
(To:pimm)

Paul, I may have come up with something. Remember I said not to dismiss patterns. Have a look at the attached model, I think its doing what you want without any relations. I cannot figure out how to attach a file with this new UI, do you know?

John

pimm
14-Alexandrite
(To:John.Pryal)

In the upper right of the window there is a Use advanced editor.

That will allow you to attach. The paperclip will be in the bottom right.

John.Pryal
12-Amethyst
(To:pimm)

ok, I figured out how to attach the file. Good Luck

John

pimm
14-Alexandrite
(To:John.Pryal)

John,

That is a very neat feature. I'm not sure how you exert control on each section but that is quite an interesting effect.

With your repeating pattern it increases 1 additional degree with each section. In my instance I need to increase all the varying drafts by just 1 degree.

I would like to learn how the pattern table works but I don't believe it will work in my case. There is too much variation and twisting to match through the series of sketches.

John.Pryal
12-Amethyst
(To:pimm)

The pattern used was not a Table pattern, it was a plain old Dimension pattern. I am still not 100% sure what you are trying to achieve, but I attach one more model which may be of use. Now the varying Drafts only increase 1 degree.

John

Patriot_1776
22-Sapphire II
(To:pimm)

It'd be nice to see the geometry you're actually trying to create, as a image file, or, better, a STEP. Why the steps?

pimm
14-Alexandrite
(To:Patriot_1776)

Frank:

I'll screen capture the other more complicated end.

Last sections.JPG

This is the reason for the sections. I copied these sections directly from the customer model. This view shows the sections fairly well but there also is a good degree of twist in which you can't see.

sections top.JPG

This picture shows the twisting involved with the datums.

I have used VSS successfully in the past in applications like this. The reason that I like this is that I was able to capture every draft angle value in a family table and by incrementing by 1 I could get a true value for this change. I would like to see how you might offset the corner intersection to reflect a 1 degree change with VSS, but this gives me a value I can trust. Unfortunately for customer proprietary reasons I can't release this model online.

John: Perhaps these pictures help explain what I'm trying to achieve. I was thinking that it would be best to show the simple part of this model, but it doesn't adequately describe the complications.

To be honest I am happy with the results I am getting from Family Tables. Someone today showed how I could use Excel to quickly change the angle value (of course that is once the numerous angle values already were captured)

I'm still holding out hope that there would be a way to parametrically change just 1 value to update all values, but until that time I'm fairly happy.

dschenken
21-Topaz I
(To:pimm)
pimm
14-Alexandrite
(To:dschenken)

David,

I have looked at numerous relational videos but I haven't found something that modifies multiple entities off a original offset value.

I talked with tech support from our CAD reseller. He didn't see any way I could change these multiple values easily. He ended up helping me do this decent with a family table.

dschenken
21-Topaz I
(To:pimm)

What does it mean ' modifies multiple entities off a original offset value'?

I expected that there was a value for each section supplied by the customer, like X and you wanted each section to have a value X+Y; so you would create a relation d1 = X1 + Y ... dm = Xm + Y for each section dimension, I understand that this idea isn't what you wanted, but I don't understand what result you did expect.

pimm
14-Alexandrite
(To:dschenken)

David,

I think you understand what I'm after correctly.

I'm needing each angle feature increased just 1 degree more than the original angle.

It appears you can only increase each feature independently with a formula as you suggest. I haven't seen that you can name all the differing independent features by a common name tag that would allow you to select and change all these features at once. Am I right???

TomU
23-Emerald IV
(To:pimm)

I realize this is a late reply, and hopefully it doesn't muddy the water too much....

Something to try. Create two top level parameters, one for the starting angle and one for the increase increment.

CURRENT_ANGLE = 10 (or whatever)

INCREMENT_ANGLE = 1

Next, create a relation statement in the first feature to initialize the starting angle: CURRENT_ANGLE = 10 (or whatever)

Next, add the exact same statement to each successive feature to increment the angle: CURRENT_ANGLE = CURRENT_ANGLE + INCREMENT_ANGLE

Also add a feature specific statement to drive each feature using the current angle. For example: d45 = CURRENT_ANGLE

You will probably get Creo complaining about some features being out of date (because the value changes on every regen.), but it should work.

pimm
14-Alexandrite
(To:TomU)

Tom,

Don't worry about muddying the waters. I'm past the stage where I will change what I have done, but I still would like to know whether a relational statement could easily provide a parametric solution. I'll have plenty opportunities to put this into effect.

Your idea is similar to what I thought should work.

I'm not sure this can be done any different but the one thing that scares me (and I did observe this) is whenever you have a condition on the left of the equal sign (Current_Angle) and have the same condition on the right side of the equation (Current_Angle) + Increment_Angle it would cause an increment up every time the model was regenerated.

Also, perhaps I'm wanting too much but the other inconvenient side of this is that you would have to repeat the equation correctly for 56 instances. I was just hoping that relations could snag a common name tag and repeat the pattern with anything with that string of characters.

With those 2 problems aside this would work excellent.

Patriot_1776
22-Sapphire II
(To:pimm)

Ok, so, there are no hard steps, which is what I was asking. You can create a spine trajectory for a VSS, put points at different locations (either % or distance) along that trajectory where you want to control the angle, and then use a graph feature driven by an evaluate feature (to get the spine length to use in the X direction on the graph) with relations to control the angle smoothly at those points. I.E., say, at the first point you want an angle of 30deg(sd1), at the second point you want sd1 + 1deg (this is now sd2), at the 3rd point you want sd2 + 1deg (which is now sd3), etc.

Those sections, unless those orientations are critical, lead to a bumpy shape.

I can relate the proprietary issue.

If I get some free time, maybe I'll make a quick model and send it to ya.

pimm
14-Alexandrite
(To:Patriot_1776)

Thank you Frank,

This is something I'll certainly need to use when I do offset value VSS.

Varying depths do pose a challenge to this method but it will be interesting to see how the graph you suggest would counter this issue.

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