My name is Raul Fernandez. Although I am a newbie in the freelancer world, I have worked with UML since UML 1.1 until version 2.5. This is an interesting project related to modeling a traffic ligjt system I am an experienced information system developer and architect and I have worked with several case tools like Rational Rose, Visio, ArgoUML, Visual Paradigm and Enterprise Architects. Those tools can model Use Case and some kind of CRC representation.