CPN2000 - Status and Plans - Executive Summary

The goal of the CPN2000 project is to investigate the use of novel interaction techniques to create a new version of the Design/CPN tool for editing and simulating Coloured Petri Nets. The goal is for the new system to be both more powerful and easier to use than the current system.

During the first 6 months of the project, we have conducted an intensive design process that emphasises the participation of end users: By observing users of the current tool, both novice and experts, we have developed an understanding of their work practices and captured it in a set of scenarios. By involving them in brainstorming sessions and paper- and video-prototyping workshops, we have explored a large design space of new interaction techniques. By developing software prototypes and evaluating them with users, we have confronted our evolving design with the users' needs and preferences. In this dynamic process, we are at the stage of developing version 0 of the new tool, which will be demonstrated at the international CPN workshop in mid-October.

The design of version 0 is driven by our understanding of Petri-Nets-In-Use, gathered from our interaction with users, as well as three design principles: reification, polymorphism, and reuse, that help us combine the range of interaction techniques that we have selected into a coherent interface. The new system makes intensive use of three interaction techniques:

• traditional floating palettes, where tools are selected with the mouse;
• semi-transparent "toolglasses" that can be moved by a trackball held by the left (or non-dominant) hand, and "clicked-through" with the mouse;
• "marking menus", a type of contextual menus where items are displayed radially in a circle centred at the cursor position and can be selected quickly with simple gestures.

In parallel with the design process, we have started to develop an Interaction Toolkit and an Abstract Petri Net Toolkit on top of which the new system will be built. Our software prototypes use the current versions of these toolkits.

The plan for the coming year is to continue both the design of the new tool and the implementation of the supporting toolkits. By September 2000, we plan to release version 1 of the tool, which should be sufficiently complete and robust to be used for actual production work by members of the CPN group and beta-testers.