How do I translate the WCS/UCS concept into Inventor?

[Anonymous]

Briefly, some background. I'm a programmer, not a trained draftsman nor
mechanical engineer. Last year I wrote an AutoLisp system to create a 3D
Solid Model of our product. Each unit is a custom build with the design
criteria / data stored in a text file that is created by our main design
program (FORTRAN). We are now moving toward Inventor as our drafting
package, so I'm learning it and VB at the same time.

Now, a simple explaination of my situation. With my old system in Autocad
(via AutoLisp), I would move the UCS to a specific location in space, rotate
it if necessary, pick a layer then create my 3d object. I'd repeat this
until everything was done. All of my points in space were relative to that
UCS and everything was kept in a single .DWG file with objects grouped by
layers. I learned what little I know of Autocad and Lisp while writing this
system.

Now I'm translating my knowledge into a new drawing package (Inventor) and a
new language (VBA). I know of, and have a basic understanding of, the part
files that replace the layer concept. However, I'm hung up on the
replacement for the UCS / WCS concept.

As an example, let's say I'm drawing a "C" channel plate that's 200" x 20.5"
x 0.75" with 4" legs. I want to place gussets inside the "C", horizontally
at five locations along the channel. In the old days, I'd move my UCS to the
proper location, then called a subroutine that drew my gusset at 0,0
(relative to the UCS). Now I'm thinking that I should just put this inside a
loop where I'd adjust the value of one axis to properly locate these along
the length of the channel. Is it that simple? Or do I need to set up some
kind of dimensional constraint between the end of the channel and the edge
of the gusset?

Is there someplace that I can learn / read about how to translate the
UCS/WCS concept into Inventor? I'm going to need more of this when it comes
time to assemble all these parts into a final assembly.

Thank you in advance for your help!

Eric Schultz
...an old dog learning new tricks

[Anonymous]

Inventor doesn't have a direct correlation to a UCS, but there are a couple
of things that provide somewhat similar functionality. The first of these
are 2D sketches. When you create a 2D sketch you're essentially defining a
2D coordinate system within the model (WCS). When creating the sketch you
can define the X and Y axes directions and the origin. When creating the
sketch geometry within the sketch it is relative to the sketch coordinate
system. There are also functions avaiable that allow you to convert point
between the sketch coordinate system and the world coordinate system. There
are also functions that provide the position of the sketch plane with the
model and allow you to redefine it's position.

One thing to be aware of when defining the orientation is that the sketch
plane is associative to other objects within the model. This makes the
sketch able to correctly update when the model is changed, since it
repositions itself based on the objects it is dependent on. This makes the
model smarter, but is sometimes more difficult for the programmer because
you're required to define these relationships and can't just repostion the
sketch plane arbitrarily.

The other thing that provides some of the equivalent of the UCS is the idea
of parts and subassemblies within an assembly. When you place a part within
an assembly, the position of the part is defined within the assembly. When
you in-place activate the part to work on it, you're working within the
coordinate system of the part.

Hopefully this helps a little. It's worth just spending some time
interactively modeling with Inventor what you want to create with your
program. The basic process of the program will be very much the same.

-Brian

"Eric Schultz" wrote in message
news:E1E82D6668DE0BDA74DEEB999A38A59A@in.WebX.maYIadrTaRb...
> Briefly, some background. I'm a programmer, not a trained draftsman nor
> mechanical engineer. Last year I wrote an AutoLisp system to create a 3D
> Solid Model of our product. Each unit is a custom build with the design
> criteria / data stored in a text file that is created by our main design
> program (FORTRAN). We are now moving toward Inventor as our drafting
> package, so I'm learning it and VB at the same time.
>
> Now, a simple explaination of my situation. With my old system in Autocad
> (via AutoLisp), I would move the UCS to a specific location in space,
rotate
> it if necessary, pick a layer then create my 3d object. I'd repeat this
> until everything was done. All of my points in space were relative to that
> UCS and everything was kept in a single .DWG file with objects grouped by
> layers. I learned what little I know of Autocad and Lisp while writing
this
> system.
>
> Now I'm translating my knowledge into a new drawing package (Inventor) and
a
> new language (VBA). I know of, and have a basic understanding of, the part
> files that replace the layer concept. However, I'm hung up on the
> replacement for the UCS / WCS concept.
>
> As an example, let's say I'm drawing a "C" channel plate that's 200" x
20.5"
> x 0.75" with 4" legs. I want to place gussets inside the "C", horizontally
> at five locations along the channel. In the old days, I'd move my UCS to
the
> proper location, then called a subroutine that drew my gusset at 0,0
> (relative to the UCS). Now I'm thinking that I should just put this inside
a
> loop where I'd adjust the value of one axis to properly locate these along
> the length of the channel. Is it that simple? Or do I need to set up some
> kind of dimensional constraint between the end of the channel and the edge
> of the gusset?
>
> Is there someplace that I can learn / read about how to translate the
> UCS/WCS concept into Inventor? I'm going to need more of this when it
comes
> time to assemble all these parts into a final assembly.
>
> Thank you in advance for your help!
>
> Eric Schultz
> ...an old dog learning new tricks
>
>

[Anonymous]

Thank you Brian!

I'm sure your advice will help as I work through this.

Eric
...an old dog learning new tricks

"Brian Ekins (Autodesk)" wrote in message
news:1257B98BD5A6CF63D2AE4BD719564DB6@in.WebX.maYIadrTaRb...
> Inventor doesn't have a direct correlation to a UCS, but there are a
couple
> of things that provide somewhat similar functionality. The first of these
> are 2D sketches. When you create a 2D sketch you're essentially defining
a
> 2D coordinate system within the model (WCS). When creating the sketch you
> can define the X and Y axes directions and the origin. When creating the
> sketch geometry within the sketch it is relative to the sketch coordinate
> system. There are also functions avaiable that allow you to convert point
> between the sketch coordinate system and the world coordinate system.
There
> are also functions that provide the position of the sketch plane with the
> model and allow you to redefine it's position.
>
> One thing to be aware of when defining the orientation is that the sketch
> plane is associative to other objects within the model. This makes the
> sketch able to correctly update when the model is changed, since it
> repositions itself based on the objects it is dependent on. This makes
the
> model smarter, but is sometimes more difficult for the programmer because
> you're required to define these relationships and can't just repostion the
> sketch plane arbitrarily.
>
> The other thing that provides some of the equivalent of the UCS is the
idea
> of parts and subassemblies within an assembly. When you place a part
within
> an assembly, the position of the part is defined within the assembly.
When
> you in-place activate the part to work on it, you're working within the
> coordinate system of the part.
>
> Hopefully this helps a little. It's worth just spending some time
> interactively modeling with Inventor what you want to create with your
> program. The basic process of the program will be very much the same.
>
> -Brian
>
> "Eric Schultz" wrote in message
> news:E1E82D6668DE0BDA74DEEB999A38A59A@in.WebX.maYIadrTaRb...
> > Briefly, some background. I'm a programmer, not a trained draftsman nor
> > mechanical engineer. Last year I wrote an AutoLisp system to create a 3D
> > Solid Model of our product. Each unit is a custom build with the design
> > criteria / data stored in a text file that is created by our main design
> > program (FORTRAN). We are now moving toward Inventor as our drafting
> > package, so I'm learning it and VB at the same time.
> >
> > Now, a simple explaination of my situation. With my old system in
Autocad
> > (via AutoLisp), I would move the UCS to a specific location in space,
> rotate
> > it if necessary, pick a layer then create my 3d object. I'd repeat this
> > until everything was done. All of my points in space were relative to
that
> > UCS and everything was kept in a single .DWG file with objects grouped
by
> > layers. I learned what little I know of Autocad and Lisp while writing
> this
> > system.
> >
> > Now I'm translating my knowledge into a new drawing package (Inventor)
and
> a
> > new language (VBA). I know of, and have a basic understanding of, the
part
> > files that replace the layer concept. However, I'm hung up on the
> > replacement for the UCS / WCS concept.
> >
> > As an example, let's say I'm drawing a "C" channel plate that's 200" x
> 20.5"
> > x 0.75" with 4" legs. I want to place gussets inside the "C",
horizontally
> > at five locations along the channel. In the old days, I'd move my UCS to
> the
> > proper location, then called a subroutine that drew my gusset at 0,0
> > (relative to the UCS). Now I'm thinking that I should just put this
inside
> a
> > loop where I'd adjust the value of one axis to properly locate these
along
> > the length of the channel. Is it that simple? Or do I need to set up
some
> > kind of dimensional constraint between the end of the channel and the
edge
> > of the gusset?
> >
> > Is there someplace that I can learn / read about how to translate the
> > UCS/WCS concept into Inventor? I'm going to need more of this when it
> comes
> > time to assemble all these parts into a final assembly.
> >
> > Thank you in advance for your help!
> >
> > Eric Schultz
> > ...an old dog learning new tricks
> >
> >
>
>