32 Replies Latest reply on Jun 27, 2010 6:18 PM by Dougal Hiscock

    Example of Tank with Base - A Top-Down Main Assembly with two Subassemblies 100% parametric driven by user input table inside a DT and Ref_Geometry Part.

    Mauricio Martinez-Saez

      I posted a new version of this example assembly.  See https://forum.solidworks.com/message/247837#247837 for the new file and the instructions on how to play with it.

       

      View-2.JPGTank with Base.JPG

        • Re: Example of Tank with Base - A Top-Down Main Assembly with two Subassemblies 100% parametric driven by user input table inside a DT and Ref_Geometry Part.
          Tony Greising-Murschel
          I've been messing around with your model/DT and like what you've done here.  How do you prompt your users to input the information from the DT in "Ref_geometry"?
            • Re: Example of Tank with Base - A Top-Down Main Assembly with two Subassemblies 100% parametric driven by user input table inside a DT and Ref_Geometry Part.
              Mauricio Martinez-Saez

              Just open Ref-Geometry for editing and them open the DT, that will display a data entry table, then close the table and "ref-Geometry" and the assembly will rebuild to new specs.

               

              This is just a simple example of top-down modeling, in real life the assemblies are a lot bigger and complex (some opf them have over 3000 parts and several subassembly levels), but the pinciple is the same.

                • Re: Example of Tank with Base - A Top-Down Main
                  Tony Greising-Murschel

                  Mauricio,

                   

                  I figured that's what you were doing but I wasn't sure if you had another bit of SW/Excel magic going where the part would prompt you for the information via a Macro or something.  Have you tried tying in your DT's with the configuration publisher yet?

                   

                  Thanks again!
                    • Re: Example of Tank with Base - A Top-Down Main
                      Mauricio Martinez-Saez

                      In our real work models, it work different...

                       

                      We use a product configurator which is a program in C++ where we enter the operational conditions of the product, in the case of our products (cooling towers, evaportive condensers, etc.,) those are thermal duty and ambient condition parameters such as process fluid temperatures (in and out of the system), wet bulb temperature, relative humidity, barometric pressure, etc., using this parametrers the program perform the calculations and define the thermo-mechanical and dimensional data for the product, and produce a data set which is transfer to a "data bridge" file, this is the data set used by SW to generate the model.

                       

                      The SW model have a "referencial geometry" part which contains a DT "linked" to the "data bridge" and we have a Macro which looks for changes in the "data bridge" file and if detected, update the model (the DT) as it is open.  In our case, the user enters information on a "product calculation and design program" and indicate the program on which directory want to copy the "data bridge" file, them open the "generic" SW model (which was copied before to the same directory by code inside the "product calculation and design program") and the model is automatically "morph" to the new product.

                       

                      Each product family have one "generic model" which is copied to the "new product directory" (changing the part numbers, etc. as required).

                       

                      Once the new product is created, the drawings "liked" to the parts and sub-assemblies cometimes require some manual "editing" (if the dimensions of the parts have changed to much and the drawing require a larger paper size, etc.), we have not automate yet the "drawings", since at this time, editing a drawing only requires few minutes.  But the heavy work of creating a new 3D model is done in minutes by the computer.

                       

                      I can show you how we can create a new version of a very large tube heat exchanger 3D model in less that 10 minutes, something that if you need to do from scratch will require several weeks of solid work.  The creation of the "generic model" was done in 9 weeks by one engineer and the "product configurator" was done in one week by one of our programers.  Once the model is "morph" to the new exchanger, the complete set of drawings is done in less that 10 hours of work.

                       

                      The model I posted here is only a very simple example of how top-down modeling can be done.  A long time ago I also posted a simple macro to update all DT's inside a model.  I belive it still here in the forum.

                        • Re: Example of Tank with Base - A Top-Down Main
                          Tony Greising-Murschel

                          Which KBE product do you use?  In my former life I was an AE for Mechworks s.r.l. (maker of the DBWorks PDM system) and we were heavily involved in getting a configurator product through the Alpha stage.  Unfortunately at my current position SolidWorks is just being proven out as an effective modeling solution so no Configurators are on the slate for now--even though I know how effective they are.

                           

                          Once SolidWorks is proven out as the solution then we would definitely be moving towards a configurator/KBE such as KBMax or DriveWorks or any of the numerous products out there.

                           

                          I have also been shying away form DriveWorks express for this reason so as not to become dependent on a kbe--even a little--until it is time to start investigating those solutions.

                           

                          I'll have to make due with DT's and the Config publisher for now which should be fine with all of the great examples on here.  I will also be downloading your macro to update names since I have already ran into issues with assembly equation variables that don't update when renamed.

                            • Re: Example of Tank with Base - A Top-Down Main
                              Mauricio Martinez-Saez

                              We do not use any commercial KBE system, since the ones we found (and we look to almost any that work with SolidWorks) only work OK on Bottom-Up models, and all our models are Top-Down and 100% parametric.  We have created our own application starting with our calculation programs.

                               

                              As mention before, our process start with operational conditions of the product, then the program perform thermodynamic calculations and produce dimensional and mechanical requirements for the product (heat exchange surface needed to produce the thermal duty, fluid passage area required to achieve fluid velocities, turbulence, etc., fan power, etc.),  with this information the program define values to be used by the SW model to "create" the new product.

                               

                              While our product can be created from a "generic" model, each product for each project is "engineered-to-order" (different dimensions, different HP on motors, larger or smaller fans, pumps, etc.)  that is why we need a "rubber" 3D model which can be "morphed" for each project.  And since we do not found a commercial application that works for us, we decide to develop our own,  we start in 2005, and by 2007 it was working.

                               

                              To give you an idea of what we have in simple terms.... we have a modern manufacturing facility with over 250 people, producing engineered to order products... the complete engineering department (including two CNC programmers) is 7 people (including me which I am the director of engineering, therefore I do not work...:-) ).  and with only 7 people (only 3 of them work on SW) we keep the production floor at full steam...

                                • Re: Example of Tank with Base - A Top-Down Main
                                  Kevin Bennett

                                  Mauricio, you should really take a look at KBMax ...  it works well with Bottom-Up AND Top-Down modelling.  Rules are developed in VB.NET, and it has a full API for extensibility.  The advantages in a case like you describe would be the following:

                                   

                                  -Time can be saved on modelling:  using the design table approach it can get difficult to understand all the relationships btw. the different entities in the model.  These relationships can be stored in the KBMax configurator instead of the model.

                                  -The rules would all be in one place, and easy to find

                                  -Since your models are already "rubber", transfer from your current system to KBMAX would be easy.  Mostly copy/pasting rules.

                                  -KBMax can be distributed around the company easily, both on local machines, intranet, and world wide web

                                  -It sounds like you already have developers... they will love the extensibility features in KBMax.

                                   

                                  If you are interested, we can take one of your assemblies and do a POC (Proof Of Concept) configurator in KBMax.  We can demo it to you online to show you how easy it was to setup.

                                    • Re: Example of Tank with Base - A Top-Down Main
                                      John Sutherland

                                      There seem to be similarities between spreadsheets, design tables and configurators; what are the differences?

                                        • Re: Example of Tank with Base - A Top-Down Main
                                          Mauricio Martinez-Saez

                                          22506 wrote:

                                           

                                          There seem to be similarities between spreadsheets, design tables and configurators; what are the differences?

                                           

                                          I will try to explain the differences in our case and how each element work on the complete system.

                                           

                                          In our case, our real models are a lot larger and more complex that the simple example of the tank.  90% of out work is related to heat dissipation equipment (cooling towers, evaporative fluid coolers, condensers, heat exchangers, etc. as well as large HVAC equipment), on which the size and characteristics of the product is driven by thermal duty parameters (nature and volume of fluid being processing, delta T, pressure, max. velocity, air wet bulb temperature, etc.) required to perform the thermodynamic calculations and determine the require heat exchange surface, cooling tower's wet deck volume, size and power required by the mechanical equipment (pumps, fans), etc., and therefore the configuration and dimensions of the equipment.

                                           

                                          The first element in our system is a "PRODUCT CONFIGURATOR".  This are a variety of programs (some done in C++ and some in VB, others are done using Excel and VB modules, in our case each family of products uses a different program, since each type of product require a different mathematical model), we enter the operating conditions and physical constrains (max. dimensions, etc.)  into the program, which perform all required calculations (fluid and gas properties, thermodynamics, psychometrics, etc.) needed to define the configuration required for the product, generating the operating specifications as well as all the data required to drive the CAD model.

                                           

                                          The data (to be used by the CAD model) is then saved to a "bridge" file (an Excel spreadsheet) which is saved on the same directory of the model to be configured.

                                           

                                          The model have one or more Design Tables, more that one is used only when required, but normally only one placed inside a "Reference Geometry" Part or Assembly (depending on the complexity of the model) which drive the reference geometry sketches.  All the values on the design tables are "linked" to values on the bridge file using Excel functions or User Defined Functions (VB modules) which convert the basic data from the "bridge file" into the complete data set required by the CAD to configure the entire model.

                                           

                                          We only enter data on the "Product configurator", we do not enter any data on the "bridge file" or the Design Tables, those are only elements used to pass values to the CAD model, in fact all the cells on our design tables have formulas or functions, and the "bridge file" is a two column file, column A have a "code" and Column B have values,  the Design Tables read those values into some of their cells using Vlookup functions or performing calculations using values on the "bridge file"

                                           

                                          To update design tables we use a macro which open the "Reference Geometry", update the design table, rebuild all the sketches and save the "Reference Geomety" file (part or assembly) which only contain sketches, then we open the model which contain instances of the "Reference Geometry" (complete or portions of it, as required) and as the model open it rebuilt to the new configuration driven by the "Reference Geometry".

                                           

                                          The aforementioned take care of the 3D model, the update of drawings (all parts and sub-assemblies have "attached" drawings) is part of another process, which is not fully automated yet, and sometimes require some "manual" editing work of some drawings, such as when the part or sub-assembly experiment a large change in dimensions or shape (change paper size, reposition some anotations, etc.). 

                          • Tank with Base - A Top-Down Main Assembly...
                            Steve Calvert

                            Sorry, the title was too long so I shortened it.

                             

                            That's really cool.  I like how you did this.

                             

                            Steve

                            • Re: Example of Tank with Base - A Top-Down Main Assembly with two Subassemblies 100% parametric driven by user input table inside a DT and Ref_Geometry Part.
                              Patrick Girvin

                              Mauricio,

                              I just wanted to say thanks for all your detailed examples and models within this forum.  They are great references for top-down and parametric design, coming from someone with lots of real-world experience.  Myself, I am adapting SW to work for architectural design, which is of course a top-down and bottom-up exercise.  There are lots of sub-assemblies (stud walls, framing, brick) which benefit from a top-down approach, and lots of off-the-shelf components (windows, equipment, etc.) that are fundamentally bottom-up.  I have gone through your posts and it has helped me.  Gracias!

                              • Re: Example of Tank with Base - A Top-Down Main Assembly with two Subassemblies 100% parametric driven by user input table inside a DT and Ref_Geometry Part.
                                Chad Schmidt

                                Hi Mauricio,

                                 

                                How would I use your same example to control the suppression or change the configuration of a part that resides in the lower level assemblies?  Do I have to create a design table in one of the parts and have it reference an external spreadsheet.  This is exactly the workflow I'm looking for but I don't understand how I might be able to leverage configurations into all this.

                                  • Re: Example of Tank with Base - A Top-Down Main Assembly with two Subassemblies 100% parametric driven by user input table inside a DT and Ref_Geometry Part.
                                    Mauricio Martinez-Saez

                                    Chad,

                                     

                                    There are many ways to control the configuration of parts al lower levels from a DT at the top level, one of them is by controlling the configuration of the upper level which will control the configurator of the sub-assemblies and parts down into the structure.

                                     

                                    The easy way to explain this is with a model (a sample),  now I am saturated with work, however as soon as I have some time to spare, I will add that functionality to the sample on this post (adding some parts at the lower level that will have more that one configuration), however, in a large percentage of instances, you can change the configuration of a part modeled Top-Down without using more that one configuration.  One of the "valid" reasons to use multiple configurations on a Top-Down parametric model is when you are using the same part on several places of the assembly and depending on the position the part need to be different, but for some reason, you want to have a single part file,  in fact, a part with two configurations is a single file with "two" virtual parts inside (each configuration have a complete data set inside the file).

                                     

                                    For reasons that are to long to explain, I am not a "big" fan of "configurations", and I only use them when I can not achieve the same without them.

                                     

                                    One the reasons.... model a complex Sheet Metal part with two configurations (configuration one suppress a couple of features such as perforations, and configuration 2 unsuppress those perforations and suppress some other features), then make a "mirror copy" of that part having "reverse geometry", mate the mirror part using upper assembly planes and origin (since the mirror is done using a plane), and chances are that the "mirror" part will show a FALSE "rebuild" error that will NEVER go away... The problem is that the FALSE error will force a complete rebuild every time you save the assembly... this in a large assembly (900Mb of files) is a real killer...  is a bug of SW that have not being fixed because it do not happen all the times since it depend on the particular structure of the part.  If you can not duplicate this I can post a sample of an assembly with two parts (an original and a mirror) showing this behavior. 

                                  • Re: Example of Tank with Base - A Top-Down Main Assembly with two Subassemblies 100% parametric driven by user input table inside a DT and Ref_Geometry Part.
                                    Derek Bishop

                                    Mauricio,

                                     

                                    I'd like to echo the thanks of others for your efforts and generousity. It is good to be able to catch glimpses of the kind of thing that can be done on plant design using SolidWorks. It sounds like you have got a good workflow going here.

                                    • Re: Example of Tank with Base - A Top-Down Main Assembly with two Subassemblies 100% parametric driven by user input table inside a DT and Ref_Geometry Part.
                                      Greg Van Arsdale

                                      Hi Mauricio,

                                       

                                      Let me begin by telling you that I am a real fan of yours.  Your thoughtful approach to automating engineering tasks using SW is very refreshing.

                                      I also want to commend you for taking the time to share your extensive experience with this community.  A sincere THANK YOU.

                                       

                                      My employer has a different group than the group that I'm in, which is a supplier to your company (plastic media).  Small world!  My group engineers submerged, multi-shaft, non-metallic, chain and flight conveyors for the water treament industry.  They are all the same, but different.  English vs. metric fasteners.  The spec'd alloy for the fasteners. Size of the basin. One motor-reducer per mechanism, vs. multiple mechanisms driven by a double or triple output motor-reducer. etc. etc. You get the idea...

                                       

                                      We have a desire to automate our ETO systems using SolidWorks.  We have spent significant money on third party CAD add-in software with rather limited results to show for it to date.

                                       

                                      May I ask one or two questions.

                                       

                                      First, Are you generating your customer's Bill of Deliverables using SW BOMs, or is this the function of your front end custom configurator, or is it done manually by a human being ?

                                       

                                      Second,  Does your company concern itself with searching for and reusing existing item numbers, or is every design "brand new", even though you may be redefining a part design that already exists as an item number in your MRP system?

                                       

                                      These are a couple of the issues that we need to be concerned with in our local corporate culture.  I was just wondering if you have encountered and / or addressed these types of "hurdles".

                                       

                                      Thanks again for all your wisdom and your kindness to share it.

                                       

                                      Enjoy this day,

                                       

                                      Greg

                                        • Re: Example of Tank with Base - A Top-Down Main Assembly with two Subassemblies 100% parametric driven by user input table inside a DT and Ref_Geometry Part.
                                          Mauricio Martinez-Saez

                                          2739 wrote:

                                          ...........

                                           

                                          May I ask one or two questions.

                                           

                                          First, Are you generating your customer's Bill of Deliverables using SW BOMs, or is this the function of your front end custom configurator, or is it done manually by a human being ?

                                           

                                          Second,  Does your company concern itself with searching for and reusing existing item numbers, or is every design "brand new", even though you may be redefining a part design that already exists as an item number in your MRP system?

                                           

                                          These are a couple of the issues that we need to be concerned with in our local corporate culture.  I was just wondering if you have encountered and / or addressed these types of "hurdles".

                                           

                                           

                                           

                                          Greg,

                                           

                                          1.- We create our BOD using  SW BOM's which are build using custom properties and data pass from DT's (which also contain data coming from the front end configurator),  in the future we plan to do this in process as follows:

                                           

                                          Manual Entry >> Front end configurator >>

                                                                                                         DT's >> SW >>

                                          Manual Entry >>>>(when required)>>>>>>                       I

                                                                                                                                >> MRP  >> BOM's / BOD's

                                                                                                                                I

                                          Manual Entry >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

                                           

                                          2.- In our system parts which are unique have a part number,  two parts that are equal must have the same part number,  on our MRP we can not have a two part numbers for the same physical part.

                                           

                                          3.- Yes "corporate culture" is a barrier any time you try to change anything....

                                           

                                          Send me an email and will give you my Skype account, there we can talk and I can give you a lot more information, etc.

                                           

                                          I imagine, the other company in your group is the one that provide us with PVC Laminar Fill for Cooling Towers, correct?.

                                           

                                          Regards,

                                            • Re: Example of Tank with Base - A Top-Down Main Assembly with two Subassemblies 100% parametric driven by user input table inside a DT and Ref_Geometry Part.
                                              Greg Van Arsdale

                                              Hi Mauricio,

                                               

                                              The delay in my reply is due to my spending some time to really understand all the aspects of your tank example.

                                              It is very elegant and relatively simple!  I am inspired.

                                               

                                              I have been trying to figure out how you accomplish "search and re-use" for your part numbers.  My best guess is that perhaps your company is using a "smart" part number system, where model features and sizes are concatenated to generate a unique and descriptive item number.  Am I on the right track with that assumption?  Here we use a dumb item number, but our descriptions are generated as described above.

                                               

                                              I'm laying awake at night trying to envision the best approach for our company to automate our engineering document creation.  I can't decide if I should try to tackle our entire system from a top-down methodology, or take a modular sub-system approach.

                                               

                                              rectangular longitudinal sedimentation basin - aka clarifier.tif

                                               

                                              I'd love to buy you a cup of coffee and chat all day long.  But alas, we have work to do!  greg.vanarsdale@polychemsys.com  Please feel free to email me directly at your convenience.  Thank You again for your wisdom and generousity.

                                               

                                              Enjoy this day,

                                               

                                              Greg

                                                • Re: Example of Tank with Base - A Top-Down Main Assembly with two Subassemblies 100% parametric driven by user input table inside a DT and Ref_Geometry Part.
                                                  Mauricio Martinez-Saez

                                                  Greg,

                                                   

                                                  Your assumption is correct, we use a "Smart" part codification system which not only identify the size and features of the part (or the nature in case of purchased components) but also the position inside the assembly and product family.  For example for fabricated parts:

                                                   

                                                  11-2222-33-444-555555-666-777777

                                                   

                                                  Where:

                                                  1 = Product Family Identifier

                                                  2 = Product Model Identifier

                                                  3 = BOM (Sub-Assembly) Level

                                                  4 = Sub-Assembly Identifier

                                                  5 = Class (Define Material, and Process, for Example

                                                            021220 = G-235 Galvanized Steel, 12ga, Punch and Formed

                                                            031420 = 304 Stainless Steel, 14ga, Punch and Formed

                                                            060080 = Type "C" FRP, Open Mold

                                                  6 = Component Family (Columns, Beams, Brackets, etc.)

                                                  7 = Part exclusive code

                                                   

                                                  The aforementioned is just and example, in real life in our system, part numbers are generated by the MRP, when a part is used on several products or in several sub-assemblies codes 1, 2, 3 and 4 have an especial code, which allow to identify on which BOM's the part is used and which is the assembly controlling the part.

                                                   

                                                  As you can imagine, the codification and control of all the parts is not as simple as it may sound here, in our case over 95% of parts have a CNC program (for turret punch, NC Bending, etc.) and we need to do nesting consolidating production orders of different models in order to define material requirements and optimize material utilization, all of that add complexity to the system.

                                            • Re: Example of Tank with Base - A Top-Down Main Assembly with two Subassemblies 100% parametric driven by user input table inside a DT and Ref_Geometry Part.

                                              So am I correct in saying nobody uses SW blocks to great things. I have tried and the are a pain in the aZZ.

                                               

                                              I have used your techniques in pro/E as well and they work much the same. I have thought of a new way of doing this that I am going to try and implement shortly. The problem I have is that if I use one master sketch to do the whole assem than I get a fairly messy system at the end once all of the sketch is done. But if I make the sketches in the assem level for each sub assem than they would stay small and more reliable(each sub assem is parts that are mated together and do not move, then in the main assem is were I mate them to move with other sub assem. In short sub assem are a collection of parts that all move together). Than any info that needs to be the same in all assems like widths and lengths of certain things I just add as a parimeter in the main assem and can easily send that info to each small sub assem. This also remove the layout part from the bom as it does not exist. The layout is in the main assem and sub assems themselves.

                                               

                                               

                                              What do you think of this idea. I am doing this in Pro/E but from my experiance they both work the same. Any problems you can see with this design.

                                                • Re: Example of Tank with Base - A Top-Down Main Assembly with two Subassemblies 100% parametric driven by user input table inside a DT and Ref_Geometry Part.
                                                  Mauricio Martinez-Saez

                                                  38806 wrote:

                                                   

                                                  So am I correct in saying nobody uses SW blocks to great things. I have tried and the are a pain in the aZZ.

                                                   

                                                  I have used your techniques in pro/E as well and they work much the same. I have thought of a new way of doing this that I am going to try and implement shortly. The problem I have is that if I use one master sketch to do the whole assem than I get a fairly messy system at the end once all of the sketch is done. But if I make the sketches in the assem level for each sub assem than they would stay small and more reliable(each sub assem is parts that are mated together and do not move, then in the main assem is were I mate them to move with other sub assem. In short sub assem are a collection of parts that all move together). Than any info that needs to be the same in all assems like widths and lengths of certain things I just add as a parimeter in the main assem and can easily send that info to each small sub assem. This also remove the layout part from the bom as it does not exist. The layout is in the main assem and sub assems themselves.

                                                   

                                                   

                                                  What do you think of this idea. I am doing this in Pro/E but from my experiance they both work the same. Any problems you can see with this design.

                                                   

                                                  Randy,

                                                   

                                                  The example of the tank, is just a small simple assembly just to show the technique, in real life, our assemblies (which are very large and complex) have a "Reference-Geometry" Sub-Assembly placed inside the main assembly, which contain Sub-Assemblies and Parts having only sketches,  then those sub-assemblies and parts are used (an instance of them) inside the actual sub-assemblies the model).

                                                   

                                                  Doing this, you can open just the "referece-geometry" sub-assembly or any of the reference-geometry "parts" and edit them without having all the 3D solids loaded,  also any change made on any reference-geometry sketch will propagate to the entire model.

                                                   

                                                  We do not do "large sketches" in fact what we do is a large number of small sketches inside parts (that do not contain any feature) so we can insert them where they are required.

                                                   

                                                  Is similar to what you describe, the only difference is that all the "relations" are build inside a "reference-geometry" sketch.  Using this approach, you can have several versions of the "preferential-geometry" sub-assembly and as you "replace" this assembly inside a large model, the entire model will change.  So you can have 1000 variations of the the product having a single 3D model and one "referential-geometry" sub-assembly for each variation.

                                                   

                                                  Is to complex to explain without looking into a large model and see the structure and how all the components are linked, but I believe ths will give you a good idea of how we do it.

                                                    • Re: Example of Tank with Base - A Top-Down Main Assembly with two Subassemblies 100% parametric driven by user input table inside a DT and Ref_Geometry Part.

                                                      Just an update on what I did. I used the idea I had in the previous post. Here is a quick recap:

                                                       

                                                      I made each sub assem to include only parts that move together(as an example a hydraulic cylinder would be made of two sub assems)

                                                      I then included any universal data in the main assems parameters(its kinda like tables only not as good)

                                                      I then mated all assems together based on there pivots(this could all so work to link parts that don't pivot but that's not what I wanted here)

                                                      Now if I update any main perimeters all the sub assem that need any updating will update. And if they don't need to update they don't, saves on reload time as the way I did it before all sub assems used the same MASTER sketch so to speak so if you changed anything Pro/E wanted to update everything.

                                                      As of now a much better system.

                                                       

                                                       

                                                       

                                                      Once again I know I am using Pro/E here but the idea is the same and will work much the same in both programs.

                                                       

                                                       

                                                      I have attached a pic of what my sidebar looks like with the assem and sketch inside them. I dont accually have any parts in them but you can see how its layed out.

                                                       

                                                       

                                                       

                                                      As for you Mauricio is this what you are saying more or less.

                                                       

                                                      You have a layout assem with layout and part SKETCHES that is added to you accual product assem. Then you reference these for whatever needs it to make you actual product. The layout assem and sketchs is linked to your table to get its measurement and the table is linked to your configurator which you input information in and in generates the dimensions and whatnot for the table.

                                                       

                                                      I like that but I am a one man show and I can get the complicated with the outside coding and stuff. But for what I am designing which is only a few products and the assems are mostly under 300 parts included all hardware this way will do.(At least until I find a better way of course)

                                                      • Re: Example of Tank with Base - A Top-Down Main Assembly with two Subassemblies 100% parametric driven by user input table inside a DT and Ref_Geometry Part.

                                                        So is this more or less what you assem would look like

                                                         

                                                         

                                                        Referance asm

                                                             Layout Front Wheels prt

                                                             Layout Rear Wheels prt

                                                             Layout Frame prt

                                                        Car asm

                                                             Front Wheels asm

                                                                  Layout Front Wheels prt

                                                                  Wheel prt

                                                                  Front Wheel Parts Here

                                                             Rear Wheels asm

                                                                  Layout Rear Wheels prt

                                                                  Wheel prt

                                                                  Rear Wheel Parts Here

                                                             Frame asm

                                                                  Layout Frame prt

                                                                  Frame Parts Here

                                                          • Re: Example of Tank with Base - A Top-Down Main Assembly with two Subassemblies 100% parametric driven by user input table inside a DT and Ref_Geometry Part.
                                                            Mauricio Martinez-Saez

                                                            Cose to what you show on your post, however, normally you have fasteners on assemblies which fix one part to another using holes that need to be on same position on both parts, this requires an sketch that control the position of the holes on all parts joined by the same fasteners, therefore the structure will look like the following

                                                             

                                                            Car Main Assembly

                                                             

                                                                 Referance Geometry Sub-Asm

                                                                      Main Lay-out Sketch

                                                                           Fastener Holes Position Ref-Geometry Part (Contain only sketches)

                                                                                Body Sub-Asm Ref-Geometry Part (contain only sketches)    

                                                                                Chassis Sub-Asm Ref-Geometry Part

                                                                                Layout Front Wheels prt

                                                                           Layout Rear Wheels prt

                                                                           Layout Frame prt

                                                             

                                                                 Body Sub-Asm

                                                                      Body Asm Ref-Geometry (Copy of)

                                                                      Body Parts

                                                             

                                                                 Chassis Sub-Asm

                                                                      Chassis Sub-Asm Ref-Geometry Part

                                                                      Chassis Parts

                                                             

                                                               Front Wheels asm

                                                                  Layout Front Wheels prt

                                                                  Front Wheels Sub-Asm

                                                                                Front Wheel Parts

                                                                

                                                                     Rear Wheels asm

                                                                 Layout Rear Wheels prt

                                                                 Rear Wheels Sub-Asm

                                                                    Rear Wheel Parts

                                                             

                                                                Frame asm

                                                                  Layout Frame prt

                                                                  Frame Parts Here

                                                             

                                                            In other words, there will be reference geometry needed to drive more that one sub-assembly (an example of this are the holes for fasteners, but also are many other situations).

                                                             

                                                              • Re: Example of Tank with Base - A Top-Down Main Assembly with two Subassemblies 100% parametric driven by user input table inside a DT and Ref_Geometry Part.

                                                                Interesting, that told me more about what you were talking about than you probably realize. I was doing the same thing before only I had one part in the main assem as opposed to many different parts for different things. That's why it got so messy. I was thinking today and what yours looks like is exactly what I thought I would try next. One question though. Is the ref assem static or can you move and interact the sketches.

                                                                 

                                                                 

                                                                I also use the hole thing to make all fasteners line up and be the right size. Then you change one bolt size and they all change in the same group.

                                                                 

                                                                This is a great alterative to the crappy top down in both programs. Although I think with pro/e's advanced assems add-on it has a pretty good setup but like I have an extra 5 grand lying around.

                                                                  • Re: Example of Tank with Base - A Top-Down Main Assembly with two Subassemblies 100% parametric driven by user input table inside a DT and Ref_Geometry Part.
                                                                    Mauricio Martinez-Saez

                                                                    38806 wrote:

                                                                     

                                                                    ......One question though. Is the ref assem static or can you move and interact the sketches.

                                                                     

                                                                     

                                                                    I also use the hole thing to make all fasteners line up and be the right size. Then you change one bolt size and they all change in the same group.

                                                                     

                                                                    This is a great alterative to the crappy top down in both programs. Although I think with pro/e's advanced assems add-on it has a pretty good setup but like I have an extra 5 grand lying around.

                                                                    Randy,

                                                                     

                                                                    If you know how to stablish the realtions (it is somehow tricky) the ref assembly can have sketches that move and have the sketches related to it follow.  We do that on a lot of our assemblies.  Aslo, once a ref-geometry part is related to an upper level ref-geometry entity, you can insert it on a sub-assembly in one position and on another sub-assembly on a different position and all the instances will update as the original one change.

                                                                     

                                                                    About fasteners, we "drive" size and quantity of fasteners using the "holes" ref-geometry.  In our case some of the fasteners are structural rivets where you need to control not just the diameter but also the exact "grip" (with bolts you have discrete lengths such as 0.75", 1", 1.125" 1.5", etc. but with structural rivets the "grip" = sum of thickness of parts joined by the rivet).

                                                                     

                                                                    Randy, this methodology have nothing new... I used it with Pro-E back in 1993  (Pro-E on HP Unix workstations at the time) and before that with ANVIL-5000.  This as old as "parametric" CAD applications, the problem is that it is not explained on manuals or training courses,  but any engineer doing desing of new products uses it, since allways a product will requiere changes during the design cycle and if you do not what to redo the work each time you perform structural calculations with the FEA, you better have a true parametric assembly (or perform every calculation before you start drawing lines).

                                                                      • Re: Example of Tank with Base - A Top-Down Main Assembly with two Subassemblies 100% parametric driven by user input table inside a DT and Ref_Geometry Part.

                                                                        In the relations thing earlier but I decided to go back to the static sketch instead as I have many parts dimensions that are overall and position relative to other parts so it is much easier to do a static sketch of what it would look like hovering over the ground and then adjust it once it all together so that when it is on the ground with weight on it set up just right. Its a pain to try and us parameters and things to try artificially local where a part should be in respect to another in order to get the right measurements when one part in the assembly is moved. But for the complexity and what I need it for a static sketch will work much more reliably and allow me to dimension things how I want to.

                                                                         

                                                                        As far as fasteners go I just get the hole side right and sometimes depth and then go onto Mcmaster Carr and get the Cad for the bolt. Since I get most of my hardware from them it works well as I already have the part number in the model file that Mcmaster uses. Its kind of slow to look for the part and download it and then install it but I only have about 50 fasteners on my design and only about 20 different kinds of fasteners as far as size and length. Again probably not the best but for what I am doing and the fact that I deal with only one product it doesn't matter to much.

                                                                         

                                                                        As far as the methology goes I owe every bit of my Top-Down Design to you as about a year ago I was searching the Internet high and low to find out how to do it(and I am pretty good at searching the Internet for whatever I need) and I could not find and REAL tutorials or documentation on how to do it. Then I stumbled open one of your post on these forums and started picking up on how you set things up and slowing it started coming to form. I would build my project one way. Then I would learn the limitations and start over and try to build it in a better more reliable way. But you definitely got me started in the right direction.

                                                                         

                                                                        I agree with others that you should right a book. Or better yet maybe a video lesson series. It doesnt really even matter what program you use as it has work for me in any parametric program.

                                                                         

                                                                         

                                                                         

                                                                        Oh and before I forget I started a new design the way you showed and it is working great. Much cleaner than my old design and everything updates nicely.

                                                                          • Re: Example of Tank with Base - A Top-Down Main Assembly with two Subassemblies 100% parametric driven by user input table inside a DT and Ref_Geometry Part.
                                                                            Mauricio Martinez-Saez

                                                                            Nice to ear that my contributions to the forum help you to do a better job.  My objective was to pass information to others that may help them to use the tool more effectively.

                                                                             

                                                                            Regarding the suggestion of writing a book or create a series of tutorial videos,  maybe when I get some free time (now I am overload with work) I do something like that.  Perhaps the best will be a series of training using a WEBCASTING presentations.  A couple of times I have been approach by companies wanting to learn how to improve their CAD design process, in one occasion I was not able to do it due to my workload, another, the company do not have any "budget" to pay for training for his people.  I will provide free training to individuals, since that will help them to growth on their careers,  and since many people help me when I needed, I consider a moral obligation to provide help to others in whatever I can, but my philanthropic activities do not extend to companies and businesses.

                                                                             

                                                                            If you look at all post in this forum, you will see that a large percentage of posts show that people do not have a good understanding on how the application work, the main reason for that is that companies purchase the application and do not provide any training to their people.  It is true that sometimes is hard to find good training material and that the training provide by the majority of VAR's is very basic, but also is true that there is people that know how to use the application at very high level (some of them, without mentioning names, post regularly on this forum).  Why the VARS's on their areas do not use them to provide training to others?  Why, SW do not found a way to transfer knowledge from advanced users to new users, when that can be an excellent added value to the product?  I will say that over 50% of the people seating in front of a SW CAD workstation are using the application only to less that 40% of his capabilities, which in my opinion degrade the competitive advantage of the product,  since a CAD tool is as good as the level of knowledge that the user will have on how to use it.   You will see on this forum a large percentage of complains about bugs and "limitations" of the software that in reality are not caused by the software, but by the lack of knowledge of the user on how the application work and what can be done and how.

                                                              • Re: Example of Tank with Base - A Top-Down Main Assembly with two Subassemblies 100% parametric driven by user input table inside a DT and Ref_Geometry Part.

                                                                I am new to Solidworks and this example helped out a lot, so thanks a bunch to Mauricio and all who were involved with this discussion. I do have a couple questions regarding design tables in assemblies: Is it true that it is impossible to modify part dimensions in an assembly design table? If I have part configurations setup in the part design table can I switch between part configurations by using an assembly design table? I will greatly appreciate anyones assistance.

                                                                • Re: Example of Tank with Base - A Top-Down Main Assembly with two Subassemblies 100% parametric driven by user input table inside a DT and Ref_Geometry Part.
                                                                  Mohammad Awad

                                                                  I am new to this technique and really I'd like to get more help if available in details regarding this issue. I am working with similar to what you have described - HVAC company- especially AHU (air handling units) the vast engineering to order machines make it too hard to make new drawings for every project where most of projects are unique projects and AHU come in sections (fan section, coil section, filter section, plenum section, mixing box, humidifiers, air washers, energy wheels, etc.) this with different models from the smallest to the largest model. also the same model have many different arrangement for section which depends on the CFM, Delta T, wet bulb , dry bulb, Static pressure ..Etc.   I am really looking for an automated solution to drive my  3D designs according to the submittals being delivered from the study department where they have a complicated software's to calculate motor power, fan size, coil size,  where determining this will determine the machine size W*H*L . But the good news that we have 16 different models for the machines width and height but the length of the machines depends on the number of section according to the study and submittal I mentioned. I hope to find the best solution to overcome all the variety in designs easily and in short time.

                                                                   

                                                                  Ramzi

                                                                  • Re: Example of Tank with Base - A Top-Down Main Assembly with two Subassemblies 100% parametric driven by user input table inside a DT and Ref_Geometry Part.
                                                                    Dougal Hiscock

                                                                    Thank you for posting this example.  I have been using a similar method and wasn't sure if it was the best way or just a hack.   Now I know that if it's a hack it's the best way to hack.

                                                                    I'm happy to see the example worked in SW2009 too.