Newcastle University

"We saved a lot of time by locating design error prior to creating a physical prototype. We estimate that an entire prototype production cycle was saved due to the early and rather complete analysis of the system."
Peter van Eijk, Neopost

Neopost Technologies B.V. is based in Drachten, the Netherlands, and is one of the two world leaders in small- to-middle-range manufacturers of mail handling equipment (machines for flexible packing of multiformat documents and automated handling of incoming high volume mail). The firm has an R&D department of 75 people. The Neopost case study centres on model-based design of a document inserting system. The system is required to pick up individual pages in a preset order, transport them to a collator in correct sequence, fold the set together, pick up an envelope, open it and insert the folded set of papers before sealing the envelope and delivering the finished package to an output bin.

Neopost wished to improve the system's ability to cope with environmental inconsistencies such as small misalignments in the documents or envelopes as they are picked up. Even small misalignments can lead to uncontrolled collisions between documents and envelopes, creating paper jams and hence significant loss of productivity. For this reason, avoidance of paper jams is a key performance indicator for automated paper handling. An improved understanding of how different environmental situations contribute towards document misalignment will allow the design team to decide how to distribute their effort over the different possible improvement activities. Co-models were developed on the Crescendo platform to study the misalignments of documents with respect to each other and / or the heart line of the paper path. The Neopost engineers found several benefits to the co-simulation approach in terms of productivity:

"Even when the hardware of the feeder folder was available the engineers continued to use this simulator for two reasons:

First of all in the early stages of the project the simulator was working more reliably than the real system... by using the simulator instead of the real machine the engineers could concentrate on the development of their software instead of keeping the mechanics running. 

...The real machine turned out to be under development constantly leading to a low availability for the software engineers. When during the project the number of embedded software engineers was raised from one to three and the fact that we had only one physical model the advantage of using the simulator became of crucial importance."
Peter van Eijk, Neopost

Peter van Eijk, engineer at Neopost, comments that Neopost plan to continue developing design processes based on simulation and collaborative modelling approaches:

"Simulation will become increasingly important for Neopost. Test setups and physical prototypes will become more costly and have less availability. The Crescendo technology can be one of the critical enablers for a more model-based approach to embedded systems development."
Peter van Eijk, Neopost