SYSML16 — Requirement constants should be integrated into Model-centric vision of SysmL

SysML requirements are now pure text and not completely integrated in to
the model-centric approach

Currenltly requirements are written as

The top speed of this car shall be greater than 100 mph.

Instead, it should be written as

The top speed of this car shall be greater than <x>.

And there be a compartment of the requirement where the current value of
<x> is given

<x> = 200mph.

This <x> should be integrated as a design value throughout SysmL and
should be connectable to parmetrics. It should also support dependencies
so that other requirements value's (and block's features) can be
dependent on the value of <x>. Then I can determine all the places in my
system where there is a dependency on <x> and my equations and
constraints are automatically updated. Which in many cases would allow
me to automatically rerun my simulations.

This is an improvement in integrating the model. Currently, with pure
text requirements constants in the requirements are often repeated in
equations, parametrics, constraints, algorithms. This repeating defeats
some of the advantages of model-approach, as they are identical or
related elements that need to be synchronized by hand.

Needs to be traced to SysML20.

MARTE currently allows to define variables in text using $ sign.

Needs to be traced to SysML20.
Out of scope for RTF