Using CAD Data in ArcGIS

okay this is a short video of using CAD data in ArcGIS this video does go along with our assignment for this week called using CAD data in ArcGIS AutoCAD ArcGIS integration it also will go over some of the concepts from our PowerPoint discussion from this week it will not step through every step of the assignment but it'll it'll give you a good overview of the assignment and working with CAD data in general so it's part of this project this assignment and every project you do in GIS you typically create a a directory structure to work from in this case I told you to create a folder called CAD and inside of that CAD folder create a few other folders for me I created one called mod - CAD and inside that folder I know that I have some CAD data for this assignment and I know I'm going to save a map document so I have a map document folder as well as I've got a shapefile I'm going to work with usually I'd have multiple map documents in shape files but this is a good start for a directory structure for this particular project so I have already downloaded the data and extracted the data from Moodle I'm gonna need to create a file geodatabase because eventually I'm gonna get this CAD data translated into my geo database usually I create my geodatabases at the project level directory I don't create a folder just to put a geodatabase in I usually put it in the project level folder here it comes in an edit mode which I can just start typing to rename this is we're gonna be working with a elementary school and been from West Buncombe and so I'll just call this geo database West Buncombe so when you get some CAD data the very first thing you typically do is you have to explore the CAD data to better to gain a better understanding of how it's structured and what kind of information is in it so that's what we'll do first here and in our catalog we can look at this CAD data set and see there's many feature classes in it the feature classes you will always see are annotation polygon polyline and multipatch within these feature classes there'll be many features of your GIS that that you would like to incorporate into your GIS occasionally you see other feature classes broken out and sometimes these are valuable to you and sometimes they're not if the CAD technician worked based on the ESRI mapping specification for cat you may see more feature classes broken out into a way that they're already thematic in nature like your GIS data is in this case we see some that might be like Highway and if we preview this well you'd think that would be a highway but I don't really see much there and in the table I'm looking at the geography and I don't see any and if I look at the table well there's a there's a couple of of lines but they say they're highways but but I don't see them anywhere and so it doesn't look like that's gonna be something I can really use here's a circle feature class I'm not sure exactly what that's made of it's got some points it looks like it came off the ml1 layer I'm not sure what layer is ml1 so that doesn't look too too useful to me either maybe guardrails these are some points from a guardrail it looks like but I don't I don't see the points with the rest of my data so the feature class that I always look at and explore very closely is the poly line feature class so it's this feature class here a CAD technicians often put their their geometries line and even polygons onto a polyline feature class and you can see that this feature class like it's got a lot of GIS related information so this one feature class looks like it has a building on it this green or maybe multiple buildings it looks like I see contour lines these red and green lines look like contour lines this may be a a road up this way maybe some other kind of landscaping feature this looks like a looks like parcel boundaries to me so the point is that this one polyline feature class in the CAD data set actually has what would be in a GIS environment on many different layers in a GIS environment we would have a buildings feature class and a contours feature class and a parcels feature class so this is pretty common in the CAD world these things are all thrown onto one feature class and what we have to do is filter out based on the original CAD layer and then convert them to feature classes in our geo database so how do we do that well we see the geographies here and we can look at the table as well and you'll notice that there's a layer field and so by identifying lines you can determine what layer they were on so this which is obviously a building it's actually on the ml3 layer so let's look at this one that one's harder to slap because it has some overlapping but that building right there on the ml3 layer so that tells me that the buildings are on a CAD layer called ml3 it's not incredibly descriptive it'd be nice if that building if that layer was called building but it's not and it's often not so we have to to explore the data to figure it out how about this line here what kind of what layer is that on it's on a layer layer called C topo minor so that's a little bit more descriptive it's a topo line it's a contour line and these are the minor topo lines and the green ones in between are the major ones or the index contours so you'll see when you look at the attributes for CAD data as mentioned in our PowerPoint discussion the attributes are more commonly display types of attributes whether a layer is on or off locked maybe the color the maybe the line type and the line width so there's lots of these display characteristics and less often you'll see user characteristics like the elevation of that line although in this case you do have the elevation an important attribute though that you usually find in these layers as a as a layer attribute that tells you you can select based on the original CAD layer that the information was on so that's already starting to give us some good information let's go on and look back at this polyline feature class and the geography of it you know I think I want to pull the buildings out of this layer maybe the contour lines and maybe the the property boundary so look at this the property boundary looks like it's on ml4 and now for seem to be the the property boundaries or the tax boundaries so that's good important information or know what layer things are wrong the other thing you want to consider when you first start looking at CAD is what kind of coordinates are stored with this CAD data and if you look down here in the bottom right of the screen you'll see the numbers are they're pretty low usually a real world coordinate system like state plane coordinates or UTM coordinates or latitude and longitude for that matter will have larger numbers latitude and longitude not so much but state plan and UTM will have large numbers state plane coordinate system is in the 900,000 and 600,000 kind of range UTM is in the three hundred thousand three million range from the X&Y so what that tells me is this CAD drawing was drawn in local coordinates are not really based on a real coordinate system they just arbitrarily started drawing around 5,000 2,500 and they designed their their drawing based on that so we're going to need to in order to overlay this with with other real-world data we're gonna need to georeference this ball so before we chair reference it let's look at what we're gonna geo-reference it in relationship to so geo-reference allows us to translate or assign real-world coordinates just to a CAD file or an image that does not have real-world coordinates so if we look at this parcel layer that I provided it looks a lot like those parcel lines from the CAD data so it's the same area I pulled out the parcels just that you need and providing them so you can see here this data if you look in the bottom right has coordinates there in the nine hundred thousand seven hundred thousand range and if I look at the properties of this layer this layer is in nad83 state plane it's in state plane feet so if we geo reference our CAD data to match this parcel data that means our CAD data is going to be in state plane feet too so before we even move on the first thing I'll do is I'll just tell it that this data is going to eventually end up to be in state plane feet it has an unknown coordinate system and again since I know I'm gonna translate it geo reference it to match the parcels I know it's going to be in the same thing as the parcels currently it's unknown since I just looked at that coordinate system it shows it in my favorites if you don't see it in the favorites there you could pick it out of the projected coordinate systems you'd have to go down to state plane and find the correct one but it's easier if you know the layer you're going to translate or geo-reference based on just to import from that layer so in this case I'm gonna go import from that shapefile and it takes on that coordinate system so I have now defined the coordinate system for what this data will be eventually okay now that's a that's a nice step to go in and do now we could do that later but uh but that's a nice step to go in and take care of now now notice that does not give my data State playing coordinates if you see the coordinates down in the bottom right there still unknown this data still needs to be geo-referenced but once it is geo-referenced what that defined projection will allow it to do is to project on the fly to match data that's in a different coordinate system then what then what this is in okay so we've done a good bit of work here already just kind of inventory our data so now let's load our data into into arcmap now I could drag this whole drawing file over to arcmap and it would load all of these feature glasses but really I just want the polyline feature class because that's what we're gonna pull a little bit of data out of and and and convert it to thematic layers in our in our geo database so I'm gonna add that to this map document and if I go up here to that polyline feature class and there it is now if you didn't define your coordinate system you would get an error there saying it's not defined I did define it so it thinks it's in the state plane feet even though you see the coordinates down in the bottom right are much lower than the state plane feet so so there's my CAD data and I'm going and add my my parcel data that I'm going to geo references based on as well alright now before we do anything else I want to set up my map document appropriately and this is something you should also do and pretty much every map document you ever create under the file drop-down you can get to map document properties and under map document properties it's nice to set our default geodatabase to the database or the geo database for our project now there is this default geodatabase that's named default geodatabase that gets installed in your users Documents folder under ArcGIS when you install the software and so if you're not careful when you're working in an arcmap things get dumped to this default geodatabase it has to have some kind of default operation for data that gets created where does that data go it goes to this default geodatabase unless you tell it that you want a different geo database to be your default geodatabase now another thing we like to do is store relative paths that will help this data become more transportable if you moved from one computer to another and the drive letter changes on your flash drive this setting will stop it from from losing the location of the data that the map document references so make sure and set those to four for every map document you make let's go on and save our map document - and I'm gonna put it right here in my MXD folder this is w bunk dot MXD you can call it whatever you want that it's descriptive and makes sense to you okay so something we can do with with CAD data in arcmap is we can change the display properties so if we go to the properties of our CAD data something I wanted to point out here is that you can have a drawing layers tab and because one workflow for people who work with CAD data in ArcGIS it's that they simply overlay the CAD data with their GIS data and use it as a layer then some you can turn on and off different layers within the CAD file so we could come in here and turn everything off disable all and say just turn on the buildings and the contour lines or the buildings the parcels and the contour lines so that's turned on a little bit more but you can change how much information is shown on your CAD file this way so remember you can work with CAD data directly in arcmap without converting it to a geo database feature class however you can't edit it it's just a layer you can you can use as a read-only file so so that's fine for now we'll we'll look at it just for this now we've got our parcels later but we're in the world of the parcels well remember these are showing at the coordinates you see in the bottom right and if i zoom to the full extent of all of the data that's loaded in this data frame our parcel data is actually right up here and if you look in the coordinates in the bottom right those are state plane coordinates and all the way down here near the origin that shows the CAD data right there they're in different different places because they have different coordinates so I'm gonna zoom back in to the parcel data and I'm gonna geo reference this to match the parcel data now the geo referencing toolbar I have turned on you can turn it on by going to customize toolbars and geo referencing you can also right click in the gray area and turn on and off toolbars notice that the layer to be geo-referenced is the CAD drawing in this map document you can geo-reference CAD data and images make sure if you're working with this grr Singh toolbar if you had some images loaded in this map as well that that they were not the ones being focused here in this drop-down because that's what would be geo-referenced when you started the geo referencing process which is what we will do now so I know that I want this data this CAD data to be up here in this area where these real-world coordinates are so essentially the geoprocessing process you choose a location on the CAD data that's a non real world coordinates and then you pick the real world location represented in the parcel data to assign a real world coordinate to it this does not store the real world coordinates with the CAD data this information will eventually be stored in a world file that tells the cad data how to display so zoomed into the real world coordinates under the geo referencing dropdown we can fit to display the cad data shown in our drop-down above on the geo referencing toolbar and it just essentially throws that cad data up close to my current display and this came really close actually I actually cannot I could I could use some tools to to make it move closer I could shift it over a little bit so it gets a little closer and I could I could also scale it a little bit to make it fit more okay no it's close enough that really it's close enough that I can add control points without making it much closer so I'm gonna zoom in a little bit and add the control points remember that when you geo reference CAD data it uses a two-point similarity transformation what that does is it takes two points and it allows you to move the CAD data rotate the CAD data if you took GIS 111 at a BTech you saw geo referencing when we gia referenced a scan Matt geo referencing a image allows you to enter in more than two points and it allows you to actually rubber sheet and stretch a raster file to to better match an area CAD data you cannot do that way so two point similarity transformation it's best to pick two points around the outside of your CAD data so this corner is that corner and this corner is that corner and this corner is that corner so I'm gonna grab my control points it's very important you start with the CAD data first click one time and then click another time and that added one control point from there I'll click this one to there and there's two points using those two points from the grf scene drop-down I will now auto adjust and you see it moves it pretty darn close now it's not perfect the CAD data is actually probably more accurate than the parcel data in the GIS once CAD data from surveys is converted to parcel data in a GIS because each surveyor survey is based on their own local coordinates sometimes the GIS data has to be stretched and matched so that all the parcels fit together in a quilt work or fabric of parcels so this is pretty close and we're gonna accept it for what it is to save the world file of our geo referencing you must update geo referencing so what that does is that saves a world file that stores the from coordinates and the to coordinates just two pairs of coordinates and that world follows used to display the CAD data in that's real world coordinates again the actual CAD data is read-only and it's not updated this this world vowel just saves with the the drawing file here so when I update geo referencing you can see it's gonna save a world file it's gonna put it in my cab folder and notice it's not here now but updating geo referencing say it's that world ball to the same folder it's my CAD data and it's named the same thing with a different extension so what arcmap does now is if you've got to load this drawing file into arcmap it automatically sees that there's a world vowel in that folder and so it knows that it needs to use the two-point similarity transformations stored in that file to display this in real world coordinates the projection file allows it to project on-the-fly to match a different coordinate system if it needs to so I can open this world file in a text editor and see that it's just the from coordinates the two coordinates the from coordinates the two coordinates two sets of coordinates the geo referencing toolbar has not been around forever we used to build these files by hand and it was really easy to do the geo afternoon toolbar makes it even easier okay so with geo-referenced our CAD file so now a really common workflow after you geo reference a CAD file is that you select out information based on that layer field and then you convert it to a feature class in your geo database so I'm gonna select by attributes and I'm gonna select four layer equals ml 3 and okay you can see it selected these buildings now there are a couple of building lines or something around the the boundaries of the parcel that might be buildings on another parcel or I'm not sure what those are but we're gonna just accept that they're there for now so I've got them selected and so I can right-click this layer this CAD layer and go to data and export data and what I'm gonna do is I'm gonna export the selected features it's gonna take on the layers source the coordinate system from the layer since I define this it'll take on state plane and it's got the state plane coordinates the output feature class I want to build I'm gonna put it in my geo database feature class and I'm gonna call it building and click OK save and then ok and it's gonna ask if I want it to add it to the map sure and if we clear our selection and turn off the CAD data you'll see I have a building's feature class in my geo database now so the second one we're gonna do we're gonna select by attributes and we're gonna select for the parcel that after exploring the data I learned that it was in the ml four layer and you can see it selected there now I'll export that data export data never let it call your file export output your future class that's not descriptive enough always name it this is parcel boundary no spaces it doesn't allow spaces and also notice that these exports are automatically going to west Buncombe that's because we set it as our default geodatabase makes things much easier ok yep so that's a real common workflow and so what I've done now is I've got a parcel boundary geodatabase feature class a building feature class there in real world state plane coordinates and they came from CAD data so CAD data is a rich source of GIS data and it's easier to often convert it from cat than to then to create it from scratch now again that's a that's a real common workflow but I also want to make mention of some geo processing CAD tools or some CAD geoprocessing tools so this could be done outside of arcmap just using geoprocessing tools so there's one called feature class two feature class and if we search for it we'll find a little bit easier that's the search button there and so let's search for feature class two feature class and feature class the future glass here it is this converts we can open it and look and see what it does all right so if you look at the help converts a shapefile coverage feature class or geo database feature class to a shape file geodatabase shapefile or geo database feature class it actually also works for CAD data so what I can do is I can take this CAD layer okay and drag it over here and if I tell it to dump it to my geo database I could dump all of the lines from this into my output feature class but notice I can put in an expression so using the feature class two feature class tool I could building I'm gonna create building two I could create it telling it only to pull out layer equals ml three what this tool does is the same thing that doing select by attributes and then right-clicking and exporting dead it's a little bit cleaner and more streamlined however what I often find is that I'm spending my time in arcmap exploring the CAD data and so as I explore it it's easy just to do a select by attributes and export the data I usually don't know enough about the data just to come in here and do this without first exploring it so essentially in my workflow it's easier just to select it and export it while I'm exploring it but let's just see this work you see it chugging away down here it's processing and there's my well it failed yesterday let's just try that again and see see oh okay I had I had some zooom did this layer okay so let's just try that again I'm gonna search for it again and it remembers it here and so the input features are that West Buncombe again my outlet location is my geo database and now I'll make another file building three just made building two and let's tell it to search for layer equals ml three not sure why that failed the first time but it failed the first time yesterday I think it'll probably work this time again I'm selecting my data I'm outputting to my database I'm giving it a good name and I'm selecting out just the buildings down here and that time it did work you see the little check box feature class to feature BA class and you can see I'll make this uh maybe a thicker of red line you'll see the buildings really stand out all right there they are okay so future class to feature class is a CAD geoprocessing tool that that you may find useful there's another tool there's another tool that I want to point out to you called CAD data set to geo database and you can search for this as well and the exercise are gonna use it now this is a conversion tool that'll take the entire cad data set and it will create individual feature classes in your geo database and it will put them inside of a feature data set so again let's just drag our cad data all right so I'm gonna put my CAD file in here my CAD data set it's gonna output to my West Buncombe geo database and that's gonna create this West bunkum CAD feature data set and so inside of my geo database we have feature classes and we have feature datasets remember feature classes can be standalone but you can also organize future classes into a feature dataset so what this tool does is it creates a feature dataset and then it takes all of the feature classes from that CAD data and it dumps it into the feature dataset so it puts all of the cad data in we will just keep the defaults for reference scale and our spatial reference is correct there as well and so before we run it I want to look here at our geo database and and remind you of what's in it now notice I'm selecting my geo database and there's nothing in it here I've exported stuff to that geo database but I haven't refreshed our catalog since I have our catalog often doesn't refresh you can refresh it by going to view and refresh or pressing f5 which is what I usually do and so I've got these four standalone feature classes the buildings layer I got by selecting by attribute and exporting this building - I tried to use the geoprocessing tool and it failed for some reason building three it worked with the geoprocessing tool so what's gonna happen with this other tool is this gonna build a feature dataset and put all the future classes from the cad data in it so I'm just gonna click OK to run it it's gonna create this data set and it's gonna put all the cad feature classes in it what do I mean all the cad feature classes i mean all of these so let's just see it run it takes a while so while it runs i'm going to tell you a little bit about this tool this tool doesn't let us filter out any of our cad data based on the layer we want it to be on i am usually filtering out stuff before I put it into a CAD or into a geo database so the main use of this tool is if you happen to have multiple CAD files that have the same we refer to as the schema or the same structure for instance let's look back at this Cadfael if you had a CAD file for every Elementary School in Buncombe County and they all had the same set of feature classes they were all organized the same what this CAD data set to geo database tool really allows you to do is to bulk load many different CAD data sets into a geo database in a way that it allows you to to manage many CAD data sets and and again it allows you to to do this kind of bulk load into your geo database while that finishes up the final tool that you're gonna use that I'm not gonna demonstrate it's called CAD import CAD annotation so CAD files often have some some annotation in them and they can be very valuable so that you don't have to recreate all that text in your GIS and so there's a tool for importing CAD annotation and you'll search for it as well so import CAD annotation this is the other tool that you're going to use it converts a collection of CAD annotation features to geo database annotation if you've worked with GIS much or even if you haven't it takes a lot of time to effectively and appropriately create labels and text an annotation in a GIS environment anything you can do to utilize annotation already created from some other format in this case in CAD data is it's very valuable so you're gonna use that tool as one of the last parts of your assignment now the final thing is how do you submit this work to me the submission requirements are that you sub to me a project geodatabase that includes a building feature class a property boundary annotation feature class as well as the feature dataset with all of the cad feature classes so you're going to look at all that information that just came in from that tool so the West Buncombe CAD feature dataset I created has all of these feature classes it put everything in there so let's go look at our our a geo database here here's our geo database I need to refresh it to show that and it shows all that information in it now again I usually like to break things out more thematically before I do this but essentially you need to zip your geo database and provide it to me now before you zip a geo database you need to close our catalog make sure that everything is in it you need and not more than you need you need to close arcmap save that and you zip files in arc and went in your file explorer zipping a file is a operating system function it's not really a GIS function so we're gonna zip this Buncombe West Buncombe gdb remember this is your geo database in File Explorer or Windows Explorer it is shown as a folder with a bunch of binary files in here don't mess around in this folder don't ever try to change a file in this folder and don't ever save anything else to this folder we right-click it send to compressed folder and now we've got our zip geo database to upload to Moodle for grading okay if you have any questions please contact me

Channel: Pete Kennedy

Views: 6,921

Rating: 4.7142859 out of 5

Keywords: ArcGIS, GIS, CAD, A-B Tech

Id: tPCEsoZey30

Length: 38min 11sec (2291 seconds)

Published: Tue Jan 24 2017