Universal Systems Language (USL) is a systems
modeling language
A modeling language is any artificial language that can be used to express data, information or knowledge or systems in a structure that is defined by a consistent set of rules. The rules are used for interpretation of the meaning of components in ...
and
formal method
Formal, formality, informal or informality imply the complying with, or not complying with, some set of requirements ( forms, in Ancient Greek). They may refer to:
Dress code and events
* Formal wear, attire for formal events
* Semi-formal att ...
for the specification and design of software and other complex systems. It was designed by
Margaret Hamilton based on her experiences writing flight software for the
Apollo program
The Apollo program, also known as Project Apollo, was the United States human spaceflight program led by NASA, which Moon landing, landed the first humans on the Moon in 1969. Apollo followed Project Mercury that put the first Americans in sp ...
.
[ M. Hamilton and W. R. Hackler,]
Universal Systems Language: Lessons Learned from Apollo
, IEEE Computer, Dec. 2008. The language is implemented through the 001 Tool Suite software by Hamilton Technologies, Inc. USL evolved from 001AXES which in turn evolved from AXES all of which are based on Hamilton's axioms of control. The 001 Tool Suite uses the preventive concept of Development Before the Fact (DBTF) for its life-cycle development process. DBTF eliminates errors as early as possible during the development process removing the need to look for errors after-the-fact.
Philosophy
USL was inspired by Hamilton's recognition of patterns or categories of errors occurring during Apollo software development.
Certain correctness guarantees are embedded in the USL grammar.
USL is regarded by some users as more
user-friendly
Usability can be described as the capacity of a system to provide a condition for its users to perform the tasks safely, effectively, and efficiently while enjoying the experience. In software engineering, usability is the degree to which a softw ...
than other formal systems. It is not only a formalism for software, but also defines
ontologies
In information science, an ontology encompasses a representation, formal naming, and definitions of the categories, properties, and relations between the concepts, data, or entities that pertain to one, many, or all domains of discourse. More ...
for common elements of problem domains, such as physical space and event timing.
Formalism for a theory of control
Primitive structures are universal in that they are able to be used to derive new abstract universal structures, functions or types. The process of deriving new objects (i.e., structures, types and functions) is equivalent to the process of deriving new types in a constructive type theory.
Implementation
The process of developing a software system with USL together with its automation, the 001 Tool Suite (001), is as follows: define the system with USL, automatically analyze the definition with 001's analyzer to ensure that USL was used correctly, automatically generate much of the design and all of the implementation code with 001's generator. USL can be used to lend its formal support to other languages.
[ Hamilton, M. Hackler, W.R.,]
A Formal Universal Systems Semantics for SysML
17th Annual International Symposium, INCOSE 2007, San Diego, CA, June 2007.
See also
*
Systems philosophy
Systems philosophy is a discipline aimed at constructing a new philosophy (in the sense of worldview) by using systems concepts. The discipline was first described by Ervin Laszlo in his 1972 book ''Introduction to Systems Philosophy: Toward a New ...
*
IDEF
IDEF, initially an abbreviation of ICAM Definition and renamed in 1999 as Integration Definition, is a family of modeling languages in the field of systems and software engineering. They cover a wide range of uses from functional modeling to da ...
*
Model-driven architecture
Model-driven architecture (MDA) is a software design approach for the development of software systems. It provides a set of guidelines for the structuring of specifications, which are expressed as models. Model Driven Architecture is a kind of doma ...
*
Systems modeling language
*
Object process methodology
References
Further reading
* Hamilton, M., Zeldin, S. (1976), "Higher Order Software — A Methodology for Defining Software," IEEE Transactions on Software Engineering, vol. SE-2, no. 1, Mar. 1976.
*Hamilton, M. (April 1994)
"Inside Development Before the Fact" (Cover story). Special Editorial Supplement. 8ES-24ES. ''Electronic Design''.
* Hamilton, M. (June 1994)
"001: A Full Life Cycle Systems Engineering and Software Development Environment" (Cover story). Special Editorial Supplement. 22ES-30ES. ''Electronic Design''.
* Hamilton, M., Hackler, W.R.. (2004), Deeply Integrated Guidance Navigation Unit (DI-GNU) Common Software Architecture Principles (revised dec-29-04), DAAAE30-02-D-1020 and DAAB07-98-D-H502/0180, Picatinny Arsenal, NJ, 2003–2004.
* Hamilton, M. and Hackler, W.R. (2007),
Universal Systems Language for Preventative Systems Engineering" ''Proc. 5th Ann. Conf. Systems Eng. Res.'' (CSER), Stevens Institute of Technology, Mar. 2007, paper #36.
* Hamilton, M.; Hackler, W. R. (2007).
A Formal Universal Systems Semantics for SysML. 17th Annual International Symposium, INCOSE 2007, San Diego, CA, Jun. 2007.
External links
{{Commons category
Hamilton Technologies
Formal specification languages
Systems engineering
Modeling languages