Better equation management tools?

Just ran into a problem. Trying to use equations to parametrically
drive a number of fins on a design. A master fin is patterned. The
idea was to drive the fin count and spacing with formulas and then use
various configurations to play with different options.

It's a simple matter to connect the pattern count to an equation.
It's also simple to then use this count and the available length to
figure out the resulting fin spacing.

The problem is that you can't change these as you add configurations
to the part. All you can do is suppress or un-suppress equations.

So...you would have to have ten different "fin count" equations, each
one activated by the corresponding configuration.

OK, so, maybe you can deal with this...a bit of a pain, but maybe not
so bad.

The problem comes in when you decide to add a couple of new configs
after you've set all of this up. What happens is that equations are
evaluated in the order they were entered, so a "fin count" equation
that comes after the "fin spacing" calculation equation is not seen by
the calc. When you suppress all prior "fin count" equations and
enable the new one, all prior calculations based on the new "fin
count" equation fail.

What's needed is a way to be able to move equations up and down in the
list.

Or, better yet, to be able to create equations that have the ability
to have different values assigned on a configuration-by-configuration
basis.

Any ideas?

-Martin

 

A couple things:

1. Always use a design table to regulate config-specific equations.
Otherwise, suppression states can be unstable.

2. Perhaps you don't need to have your "master" equation be config-
specific. Perhaps just one or two of the parameters can be config-
specific.

3. Sounds like you could come up with a single generic equation that
would work for all configs, if you're willing to do enough algebra and
careful typing.

4. You can cut-paste to rearrange equation order under "Edit All".

 

Use a design table?

Bob

 

How about creating sketch with dimensioned line and having dimension value controlling your pattern qty, using equation
or design tables this will work with configurations



Just an idea I have use somewhere, sometime ago.

 

How about creating sketch with dimensioned line and having dimension value controlling your pattern qty, using equation

This is a good cheat 'cause you can't drive equations from a design
table. Not what I would consider "elegant" but probably do-able as
long as you name the sketch something sensible and add a note to let
others know why you have this sketch that doesn't seem to do anything.

-Martin