topic Sketches as Calculators [Discussion] in Inventor Forum

Sketches as Calculators [Discussion]

andrewdroth — Tue, 25 Feb 2020 15:16:35 GMT

I made a video about using Inventor sketches as calculators, and I was hoping I could get a discussion going to see how others are utilizing them.

See the video here. (Sorry the about the audio levels, first timer, working out the kinks)

Re: Sketches as Calculators [Discussion]

JDMather — Tue, 25 Feb 2020 15:29:04 GMT

@andrewdroth wrote:

I made a video about using Inventor sketches as calculators, and I was hoping I could get a discussion going to see how others are utilizing them.

See the video here. (Sorry the about the audio levels, first timer, working out the kinks)

I might suggest increasing the text height too. (Tools>Application Options>General Tab>Annotation Scale)

When I was teaching my daughter trigonometry - I used sketches with driving and driven dimensions to help her see the relationships.

I make use of Sketch Blocks too as you can have relative motion within a sketch in a part file.

Re: Sketches as Calculators [Discussion]

andrewdroth — Tue, 25 Feb 2020 16:16:43 GMT

@JDMather wrote:
I might suggest increasing the text height too. (Tools>Application Options>General Tab>Annotation Scale)

Hey, that's a good idea! That would have never dawned on me.

Re: Sketches as Calculators [Discussion]

Curtis_W — Tue, 25 Feb 2020 17:14:17 GMT

Hi @andrewdroth

Nice job on the video.

I've used a lot of "calculator" sketches and linked calculator spreadsheets over the years... the game changer for me was the addition of user forms, originally VBA.....

but with iLogic its even easier to do just by dragging in the sketch parameter and creating a nice tidy calculator... change an input box to a slider and it makes the act of "fine tuning" inputs really quick and dynamic.

Also, if you were to create an ilogic out of the sketch you showed in the video for instance, you would eliminate the load/weight lines and have those exist only as user parameter, but still have easy access to them via the form.

Anyway, I think your calculator is begging to be driven by an iLogic form!

Hope that helps, Curtis

Re: Sketches as Calculators [Discussion]

andrewdroth — Tue, 25 Feb 2020 17:07:20 GMT

Thanks @Curtis_W!

I really like the idea of using a slider to tune things. A lot more intuitive for iterating a certain parameter.

I agree, an 'uncentered loads' form would be handy for anyone doing hoisting in Inventor. Might warrant another video...

Re: Sketches as Calculators [Discussion]

SBix26 — Tue, 25 Feb 2020 18:46:08 GMT

I have done this once with really great results. In trying to apply a gas spring, I created a sketch of the relevant components, along with the COG. Then I created a parametric equation calculating the force required to move the part and placed it in a text element. This updated in real time as I dragged the geometry in the sketch. I could then adjust pivot point locations and try again, minimizing the effort required, while making sure it stayed where it was supposed to. The actual design turned out just about perfect.

I would post the file, but had to leave it behind when I left the company...

Sam B
Inventor Pro 2020.2.1 | Windows 10 Home 1903
LinkedIn

Re: Sketches as Calculators [Discussion]

andrewdroth — Tue, 25 Feb 2020 19:52:34 GMT

That sounds intense!

Can you elaborate on this bit?

@SBix26 wrote:
Then I created a parametric equation calculating the force required to move the part and placed it in a text element.

Re: Sketches as Calculators [Discussion]

SBix26 — Wed, 26 Feb 2020 03:21:27 GMT

Not as intense as it sounds. It was a number of years ago, perhaps six or seven, so memory has faded a bit.

I had designed the moving part of the device in great detail, except for the locations of the gas springs which would assist the movement against gravity. If I recall correctly, I captured a sketch of the silhouette or cross section, perhaps from a drawing view, and with the center of gravity visible. I dimensioned the sketch (driven dimensions) so as to have them available as parameters, and wrote a fairly simple equation incorporating the mass of the device and the force available from the gas springs to calculate the force acting at the handle of the device. I included the result of this equation in a text element with a suitably prominent font.

As I dragged the properly constrained sketch up and down, I could see in real time the force required on the handle to balance the various loads. I then adjusted gas spring attachment points and tried again until I was happy with the overall results through the range of motion required.

I recall being kind of amazed that it actually worked that way, updating the calculated parameter in the text element in real time. Fun to demonstrate to my colleagues. Very gratifying that when actually fabricated, it worked exactly as modeled.

Sam B
Inventor Pro 2020.2.1 | Windows 10 Home 1903
LinkedIn

Re: Sketches as Calculators [Discussion]

andrewdroth — Wed, 26 Feb 2020 14:00:03 GMT

That is slick!

I never considered adding a text output.

I know what you mean about it being gratifying! It still surprises me sometimes how well it can sort out what I consider to be a complex equation\problem.

Re: Sketches as Calculators [Discussion]

swalton — Wed, 26 Feb 2020 14:15:49 GMT

I sometimes make Free Body Diagrams by projecting geometry into IDW sketches. It works ok, but I would like Inventor to have better tools to repair/relink broken projected geometry.

I like doing these FBD on drawing sketches because I can save them as PDFs and capture the calculation for future reference.

Re: Sketches as Calculators [Discussion]

andrewdroth — Wed, 26 Feb 2020 14:25:06 GMT

Here's another example.

A quadratic Equation problem from here.

By breaking the area up into components with X width, inventor can solve it easily.

Re: Sketches as Calculators [Discussion]

Cadmanto — Wed, 26 Feb 2020 21:03:51 GMT

This is intriguing to me. We have to design in a lot of camber calculations into our models and this has me thinking if there would be a way program in a calculator that would draw from the CC to select the structural member needed and have the camber calculated in, this would be a great asset to our design process.

Windows 10 x64 -16GB Ram
Intel i7-6700 @ 3.41ghz
nVidia GTS 250 - 1 GB
Inventor Pro 2020

Re: Sketches as Calculators [Discussion]

andrewdroth — Fri, 28 Feb 2020 14:21:20 GMT

Do you guys know if it's possible to pull dimensional info from content center?

At my previous job one guy had made an add-in that would create a sketch block of any AISC shape, but it pulled the info from an excel sheet.

I'm wondering if the CC data is easily accessible to ilogic or VBA?

Re: Sketches as Calculators [Discussion]

swalton — Fri, 28 Feb 2020 14:46:03 GMT

I don't know about CC, but AISC publishes a shape spreadsheet here: https://www.aisc.org/search/?query=shapes%20database&pageSize=10&page=1

Re: Sketches as Calculators [Discussion]

hosford — Fri, 28 Feb 2020 15:36:33 GMT

Curtis

Could you post a calculator sketch that uses sliders for inputs?

Re: Sketches as Calculators [Discussion]

andrewdroth — Fri, 28 Feb 2020 16:14:56 GMT

@swalton wrote:
I don't know about CC, but AISC publishes a shape spreadsheet here: https://www.aisc.org/search/?query=shapes%20database&pageSize=10&page=1

Yeah, I'm pretty sure that's what we were using. It's probably safer than going with the CC numbers anyhow.

Re: Sketches as Calculators [Discussion]

Cadmanto — Fri, 28 Feb 2020 17:40:06 GMT

When my work load dies down, I would love to dive into this deeper and see if something can be rigged up to do what I described earlier.

Windows 10 x64 -16GB Ram
Intel i7-6700 @ 3.41ghz
nVidia GTS 250 - 1 GB
Inventor Pro 2020

Re: Sketches as Calculators [Discussion]

Curtis_W — Fri, 28 Feb 2020 21:01:38 GMT

@hosford wrote:

Curtis

Could you post a calculator sketch that uses sliders for inputs?

Hi @hosford

I didn't really have a good one on hand that I could share, but here is a simple example (Inventor 2020) I threw together quickly ... hopefully without any errors 🙄

It might not be the best example in that it is using an iLogic rule to do the area calculations, whereas many sketch calculators would just use the geometry itself to generate the results, but it gives the general idea of the slider controls just the same.

I hope this helps.
Best of luck to you in all of your Inventor pursuits,
Curtis
http://inventortrenches.blogspot.com

Re: Sketches as Calculators [Discussion]

b_ruijter — Sun, 01 Mar 2020 07:59:10 GMT

Looks great,

I did a lot of calculation with inventor to. I did some calculations on hydraulic powerpacks. I combined the sketch calculation with other data in the fx. The great thing in the fx is that you can select other units. Every unit you can imagion you can select. Newtons, kg, pounds, psi, m^3 liter/minut and so on and so on.

The best thing is that if you use your units correct inventor does a unit check as well. If you make a formula that is mm * mm the unit of the result should be mm^2 otherwise you get an error. You can expand this all the way to pressure and and forces. One other great thing is you can mix input. You can do mm * mm and set the unit to square feet and inventor will convert the outcome.

If you want the best of calculation with inventor try looking in three things.

- fx

- sketch blocks

- ilogic forms

Re: Sketches as Calculators [Discussion]

leowarren34 — Sun, 01 Mar 2020 20:16:18 GMT

I do A Level Maths and Inventor is probably the only way I have to check the answers for trig and it also allows me to brush up on constraints etc

Super useful for trig, probs going to very useful when I move into the applied year of the course when we cover mechanics.