Importing cad points into excel

[fastback33]

I use Catia here at school, so i'm wondering how i can make an adjustment in cad and then the point will automatically update in excel. first I guess I should ask if this is possible?? Will i need something for the two programs to talk to each other?

second, i would like to ask about how to begin to run suspension simulation using excel, but require more reading, but in the mean time does anyone have any tips (besides searching i've read all of those).

[Mystery Steve]

Sorry, I don't have a specific answer to your question about exporting from CATIA seeing as I've never used the program (only used SolidEdge and SolidWorks extensively), but I was curious as to what your goal is. Are you running a macro in CATIA that moves your suspension points through their travel and just exporting the data for plotting purposes? Or do you just have a CAD model that you want to export the static suspension points from and then do your suspension simulations?

Is this for FS/FSAE, by chance, or is it some other project?

[fastback33]

You know, i'm not entirely sure as i've never done simulation before. What I was planning on doing was matching the camber curves of a simulation and comparing it to tire data. However I don't really know where to start on the simulation. I just wanted to get one thing done and then learn the next thing and then so on. Basically it is for design but not strictly for FSAE, more for my own use i guess.

[Mystery Steve]

Well, if this is for a class or something and you have a specific goal, it would help to share that so any advice can be tailored more specifically to your situation. In general though, I would start by picking up a copy of "Tune to Win" by Carroll Smith and "Race Car Vehicle Dynamics" by Milliken^2. You may even be able to find one or both of these in a university library.

At this point I wouldn't even be thinking about CAD. You have to do some low level analysis before you can start getting into part by part detail. Inventory all of the parts that would be on the car and estimate how much each would weight and where they would generally be located in the car. If you actual weights, then that's all the better, but reasonable estimates will at least allow you to set targets and have an initial approximation for the characteristics of the vehicle you're dealing with. Determine a reasonable range for your wheelbase by laying out a very simple sketch in the side view, in CAD or by hand doesn't matter, but just get an idea of where the major components need to go: driver, fuel tank, engine, and driveline usually drive the bulk of packaging requirements.

Once you have a general idea for packaging requirements and vehicle weight, start off with chapters 16 and 18 in RCVD. They'll cover ride/roll rates and load transfer. Set up a simple simulation with vehicle parameters (track widths, wheelbase, cg location, weight, spring stiffness, anti-roll bar stiffness, etc) as inputs and then set lateral g as your independent variable and look at the effect on load transfer at the front and rear. Then vary one of the vehicle parameters and see how it changes your load transfer.

Don't be worried about dynamic camber changes at this point. Chamber change will change through ride and roll (and steering), but if you don't know how much roll and ride you might expect it doesn't do you a lot good to consider it. Then eventually you can also start looking into steering effects. Tire data at this stage also won't do you a whole lot of good from the perspective of actually understanding what you're doing. You need to understand the individual aspects of the suspension before you can start to look at them together and optimize the entire system to do what you want it do.

Like I said, if you have any specifics about the project I'll be more than happy to help you lay out a road map for how to learn about suspension design and simulation. By no means am I the god of suspension design, but I was in your shoes just a couple years ago and I know what I would have done differently.

[fastback33]

Ah, you know what perhaps i have been a bit misleading, but it seems you are the only one willing to help at this moment, so check your PM's.

[Ciro Pabón]

Well, I cannot help you with the particulars of your design. However, this is F1Technical, so I bet somebody knows how to export from CATIA to Excel. I do it in a quick and dirt way: I use ArcGis to do the conversion in this example, but most GIS packages would do.

You simply open the DXF CAD file in ArcMap, edit its point table by adding the XYZ coordinates, if needed, and export it as a table into Excel. There are packaged functions for every step. You end with an Excel table that includes the coordinates and, more importantly, the CAD properties of every point you've exported.

1. You open a CAD DXF (drawing exchange format) file in ArcMap and "Open (its) attribute table


In the previous image, I just opened the section of the DXF file called "Points". It's the bunch of colored points to the right of the image. There are other layers called "Polygons", "Polylines", etc. in case you need other features from your drawing.

2. You clic on "Options" and then in "Export"


3. You get a DBF file, that you can open in Excel, with the attributes of the points (colour, line, layer...)


If you need the coordinates, you can use the ArcToolbox tool "Add XY coordinates" before exporting and you'll get more columns in your table, named "X", "Y" and "Z".

Another posibility, as you mentioned, and if you want real time exporting, is to use ArcGis functions via OLE/DLL, using VBasic or C++ in Catia to read the points and export them to Excel directly using the ArcGis libraries. That option would beat the hell out of any real programmer (like Mel), but if you're really pressed into it, I could help a little. Very little.

I hope this helps. There is also the remote posibility that some other member, in his work needs to take a CAD drawing and export it to other package via an Excel or text table (I do it at least once a month, to tell you the truth, just to save time).

I also hope somebody tells us about a better solution. On the other hand, this procedure takes like 2 minutes and works with all CAD packages able to export to DXF, provided you have ArcMap, a must if you ask me.

The highlighted column in the Excel table called "Handle" can be used as an ID of the points: it won't change when editing the points (unless you erase them, of course) and its unique for every point. In english: you can use that column to relate or identify the rows (that is, the points) between iterations of your work in CATIA and re-exports to Excel.

I would talk for ages about how that very same ability, the one that allows you to associate a record in a table to a feature of your drawing, is the main difference between a CAD package and a GIS package, but I've never been praised for the length of my posts.

[mep]

Best thing to run suspension simulation with CATIA is to use the kinematics module.

(rest is edited)

[fastback33]

Well, I cannot help you with the particulars of your design. However, this is F1Technical, so I bet somebody knows how to export from CATIA to Excel. I do it in a quick and dirt way: I use ArcGis to do the conversion in this example, but most GIS packages would do.

You simply open the DXF CAD file in ArcMap, edit its point table by adding the XYZ coordinates, if needed, and export it as a table into Excel. There are packaged functions for every step. You end with an Excel table that includes the coordinates and, more importantly, the CAD properties of every point you've exported.

1. You open a CAD DXF (drawing exchange format) file in ArcMap and "Open (its) attribute table


In the previous image, I just opened the section of the DXF file called "Points". It's the bunch of colored points to the right of the image. There are other layers called "Polygons", "Polylines", etc. in case you need other features from your drawing.

2. You clic on "Options" and then in "Export"


3. You get a DBF file, that you can open in Excel, with the attributes of the points (colour, line, layer...)


If you need the coordinates, you can use the ArcToolbox tool "Add XY coordinates" before exporting and you'll get more columns in your table, named "X", "Y" and "Z".

Another posibility, as you mentioned, and if you want real time exporting, is to use ArcGis functions via OLE/DLL, using VBasic or C++ in Catia to read the points and export them to Excel directly using the ArcGis libraries. That option would beat the hell out of any real programmer (like Mel), but if you're really pressed into it, I could help a little. Very little.

I hope this helps. There is also the remote posibility that some other member, in his work needs to take a CAD drawing and export it to other package via an Excel or text table (I do it at least once a month, to tell you the truth, just to save time).

I also hope somebody tells us about a better solution. On the other hand, this procedure takes like 2 minutes and works with all CAD packages able to export to DXF, provided you have ArcMap, a must if you ask me.

The highlighted column in the Excel table called "Handle" can be used as an ID of the points: it won't change when editing the points (unless you erase them, of course) and its unique for every point. In english: you can use that column to relate or identify the rows (that is, the points) between iterations of your work in CATIA and re-exports to Excel.

I would talk for ages about how that very same ability, the one that allows you to associate a record in a table to a feature of your drawing, is the main difference between a CAD package and a GIS package, but I've never been praised for the length of my posts.

Cool, seeing as how im new to this, would you mind explaining what arcmap is. From your example it seems to be just a program that is able to communicate with other's but, mind being more specific?

BTW, thankyou ciro!

[Ciro Pabón]

ArcMap is a GIS program, made by ESRI. It's the most popular GIS package in the world.

It's expensive, around U$3.000 for the basic license, but I think it's available in any torrent site, ehem. Check for "ArcGis Desktop 9.2" or 9.3. It is a large download (several GBytes), so perhaps you would like to use a simpler (and older) version, like "ArcView 3.2" (the name has changed from ArcView to ArcMap), which is around 100 Mb or so.

I guess you could use other GIS, but many of them do not interoperate with Excel. I think propietary MicroStation does it, Map3D (the Autocad version of a GIS) does it, ERDAS or MapInfo also can do it.

I'm not sure about free GIS software, but I also think you could use GrassGis, ILWIS or MapWindowsGIS (which are freeware).

In a GIS, as opposed to a true CAD program, the lines you draw are not "simple lines": they are rows in a database. So, for each object in your design, be it a point, line, polygon, hatch or whatever, ArcMap keeps a record with all the properties of the object. You can manipulate the records, add new properties or import them from a "simpler" CAD package.

It also has the topology (the shape of objects) information: it knows which objects are side by side or cross each other. For example, you can search for the lots that a road crosses, or the points that are at a distance from a car surface, something very difficult or impossible to do with a true CAD. With time the line between GIS and CAD has become more diffuse, but it's still there.