Don't use Sketchup but thinkit possible that models can be imported into MicroStation V8.
Would be better if Driving Dimensions could be made available for MicroStation; I know
the program has its own system called "Dimension Driven Design" but to my mind it was
so clumsy as to deter all but the most determined/nerdy users- actually, ALL users because
it took SO long to set up & input values.
Is your software anything like Solidworks, where a model is built, dimensions attached then
edited by double-clicking on the dimension value & entering a new value?

Regards
GD

Dear GD,

Thank you for the idea of Driving Dimensions for MicroStation. We will study this possibility.


Yes, our idea is similar to what is done in SolidWorks in 2D. But our users can put any dimension in 3D!
I am not so familiar with SolidWorks, but I think it is not possible to put the 3D driving dimension on the main diagonal of a box in SolidWorks.

Dimitry, I'm not quite sure what you are getting at here, but I have trained to BSc level, using Solidworks as the main CAD package. In Solidworks, as soon as you draw a line, that line, if fixed from the origin is given a parametric constraint. You can add further constraints by using the add relations tool- for example a concentric restraint of a smaller circle within a larger circle- for doing accurate shafts and bushes etc.

So to create a cube in Solidworks, start a new sketch by pressing the 'Extrude Solid' tool. A new sketch will start as soon as you have told Solidworks whether you want to draw on the front, right or top planes). Draw a line (say approx 100mm) from the origin in both the x and y axis. By using the smart dimensioning tool, you can adjust each line to the required length, simply by clicking on the line, and entering 100mm in a floating input box that appears. Once you have made a square, by adding two more lines, with the line tool (best to do that before adding dimensions!), the lines will turn from blue to black. This change of colour indicates that you have fully defined the sketch. Now you exit the sketch, and the square will extrude . Here you enter 100mm and press accept (a green tick at the top of the display). You should now have a '3D' representation of a cube.

At all times you are able to upgrade the model's parametric data, but you must edit extrusion data (z) separately from x and y (sketch). This of course is very different in software such as Sketchup, and the excellent SpaceClaim.

I hope that makes sense- I'm doing this while typing on my Mac, and Windows isn't open, so it's "from the top of my head" so to speak!

Tom

Thank you for this explanation, Tom!


Yes, in SolidWorks (as in many other CAD, e.g. CATIA or Inventor) you have to deal with variational (i.e. constraint-based) design in 2D and with history-based parametric design in 3D. This is not an easy-to-use mix, since it forces you to use different ways of design in 2D and in 3D. In 2D you can put any constraint you want on the elements of the sketch. In 3D only those driving dimensions are possible that are feature parameters (i.e. you are limited by the design history). And that's why you can set a dimensional constraint on the diagonal of a 2D rectangle, but cannot do the same for the main diagonal of a 3D box.

What we propose to users of our Driving Dimensions products is to apply constraints in both 2D and 3D in the same way.