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Value Identification and Waste Elimination Tool (VIWET)


As part of the LeanPPD project, we have developed an innovative value stream mapping tool called VIWET. At its core the tool makes use of the Role Activity Diagramming (RAD) notation to create pictorial representations of collaborative processes such as the design process.

Social Network diagram

Creating a model begins with a data gathering activity about the current state process. Process participants are asked about their role, which roles they interact with and how frequently. A Social Network Diagram is created which allows the identification and re-design of team and organisation structures. Improvements to information flows can also be made using this approach. Social Network Diagrams can also be created by automatically analysing Email repositories.


The next stage is to interview the performers of roles in more detail to discover what they do. The interview can be transcribed to provide text for analysis within the VIWET transcript analysis tool. Concepts and attributes are highlighted and committed to the model database. Role Activity Diagram can then be created with minimal further text input. The RAD tool can also be used independently and has many features to reduce the effort needed to create role-activity diagrams.

Transcript Mark up and Role Activity Diagram



Gantt chart generated from a RAD within VIWET

One of the key features of VIWET is that is not just a tool for creating pictures of processes. It has an underlying data model which allows the capture of time, cost, resource and many other information types. This allows the current process to be analysed in a number of ways. For example, high cost or long lead-time activities can be highlighted for improvement.

Gantt charts based on different time types such as optimistic, pessimistic and mean are generated automatically from the RAD and used to help reduce overall lead-times. The critical path can be identified and used to show how activity duration improvements affect the overall lead time. Network and PERT diagrams can also be created, automatic load levelling can be performed and Gantt charts data imported from or exported to Microsoft Project.

An important aspect of the software is that by using the verb-noun description for each activity, the VIWET software seeks to identify likely wastes and opportunities to add value to a product from an external waste and value database. The system then provides advice on how to eliminate that type of waste and hence improve the activity. Improvement actions can be documented and reported within the system. This leads to the design of future state processes which can be annotated to explain to process participants what should be done, when and how.

When a process is actually performed, activities can be exported to a diary style schedule either to monitor progress or to inform users of when they have to do a particular activity. As the process progresses any wasted time can be recorded using the in-built timing tool and the data saved for future process analysis.

Thus VIWET provides a single integrated repository for graphical, textual and numerical descriptions of both the current state and future state processes and provides a range of analysis tools in order enhance value, eliminate waste and facilitate the progression from current to future state processes.

Waste Timing Tool

VIWET data can be easily exported for use in other software within an organisation which makes use of process data, for example ERP systems.

The concepts and approaches embodied in this software have helped us to deliver significant cost and lead time improvements to partners in previous research projects and we believe that the VIWET tool can be used to facilitate lean implementation and process improvement in a wide range of companies and industry sectors. If you are interested in finding out more about this software and how you might be able to use it, or other deliverables from the LeanPPD project please contact John Keast.

Contact Details

John Keast, International Manufacturing Centre, University of Warwick, Coventry, CV4 7AL.

Tel 024 76524606 Email

Further information about LeanPPD can be found at