Activity Models

Activity models capture collections of determinate, concurrent behavior, focussing on their dependencies, timing, and resource usage. The model is therefore convenient to specifiy logistic processes, but can also capture data processing systems. The atomic pieces of behavior are called actions and have a specified (fixed or worst-case) duration. A single activity is represented as a graph with such actions as its vertices and edges capturing depdencies between actions, as well as dependencies on shared resources. Activities are determinate, if an activity is executed, all its actions are executed and specified ordering is respected.

An activity model, defines a collection of such activities and the possible sequences of activities that a given system may perform. A particular property of the activity model is that the execution of subsequent activities may overlap in time. Often, activities are executed in a pipelined manner, following the transfer of a resource from one activity to the next. Activity sequences can be done in the form of simple lists, or using Finite State Automata, possibly controlled by event feedback received from executed activities.

The behavior of activity models is captured using max-plus algebra. The state of the system is captured by a max-plus vector of resource availability times. Starting and completion times of actions can be expressed as (max-plus-) linear combinations of the resource availabilities and the effect on system state (resource availability) of an entire activity can be captured by max-plus matrix-vector multiplication. An activity model that executes a sequence of different activities can be viewed as a switching max-plus-linear system.

Users can define activity models using the Eclipse LSAT™ (Logistics Specification and Analysis Tool ) tool [1]. This tool embeds a domain-specific language [2] for activity models and some related analysis methods [3]. A case study of modelling the wafer logistics in lithography machines is presented in [4].

Selected Related Publications

• B. van der Sanden, “Performance analysis and optimization of supervisory controllers,” PhD Thesis, 2018.
  [Bibtex]

  @PhdThesis{San18,
  author = {Bram van der Sanden},
  title = {performance analysis and optimization of supervisory controllers},
  school = {Eindhoven University of Technology},
  year = {2018},
  }

• T. Basten, J. Bastos, R. Medina, B. van der Sanden, M. C. W. Geilen, D. Goswami, M. A. Reniers, S. Stuijk, and J. P. M. Voeten, “Scenarios in the design of flexible manufacturing systems,” in System-scenario-based design principles and applications, Cham: Springer international publishing, 2020, p. 181–224.
  [Bibtex]

  @Inbook{BBMea20,
  author="Basten, Twan
  and Bastos, Jo{\~a}o
  and Medina, R{\'o}binson
  and van der Sanden, Bram
  and Geilen, Marc C. W.
  and Goswami, Dip
  and Reniers, Michel A.
  and Stuijk, Sander
  and Voeten, Jeroen P. M.",
  title="Scenarios in the Design of Flexible Manufacturing Systems",
  bookTitle="System-Scenario-based Design Principles and Applications",
  year="2020",
  publisher="Springer International Publishing",
  address="Cham",
  pages="181--224",
  doi="10.1007/978-3-030-20343-6_9",
  url="https://doi.org/10.1007/978-3-030-20343-6_9"
  }

References

[1] B. van der Sanden, Y. Blankenstein, R. Schiffelers, and J. Voeten, “Lsat: specification and analysis of product logistics in flexible manufacturing systems,” in 2021 ieee 17th international conference on automation science and engineering (case), 2021, pp. 1-8.
[Bibtex]

@INPROCEEDINGS{SBSV21,
author={van der Sanden, Bram and Blankenstein, Yuri and Schiffelers, Ramon and Voeten, Jeroen},
booktitle={2021 IEEE 17th International Conference on Automation Science and Engineering (CASE)},
title={LSAT: Specification and Analysis of Product Logistics in Flexible Manufacturing Systems},
year={2021},
volume={},
number={},
pages={1-8},
doi={10.1109/CASE49439.2021.9551412}
}

[2] B. van der Sanden, J. Bastos, J. Voeten, M. Geilen, M. A. Reniers, T. Basten, J. Jacobs, and R. R. H. Schiffelers, “Compositional specification of functionality and timing of manufacturing systems,” in 2016 forum on specification and design languages, FDL 2016, bremen, germany, september 14-16, 2016, 2016, p. 1–8.
[Bibtex]

@InProceedings{SBVea16,
author = {Bram van der Sanden and Jo{\~{a}}o Bastos and Jeroen Voeten and Marc Geilen and Michel A. Reniers and Twan Basten and Johan Jacobs and Ramon R. H. Schiffelers},
title = {Compositional specification of functionality and timing of manufacturing systems},
booktitle = {2016 Forum on Specification and Design Languages, {FDL} 2016, Bremen, Germany, September 14-16, 2016},
year = {2016},
pages = {1--8},
doi = {10.1109/FDL.2016.7880372},
timestamp = {Wed, 24 May 2017 08:31:17 +0200},
url = {https://doi.org/10.1109/FDL.2016.7880372},
}

@PhdThesis{San18,
author = {Bram van der Sanden},
title = {performance analysis and optimization of supervisory controllers},
school = {Eindhoven University of Technology},
year = {2018},
}

[4] B. van der Sanden, M. Reniers, M. Geilen, T. Basten, J. Jacobs, J. Voeten, and R. Schiffelers, “Modular model-based supervisory controller design for wafer logistics in lithography machines,” in 2015 acm/ieee 18th international conference on model driven engineering languages and systems (models), 2015, pp. 416-425.
[Bibtex]

@INPROCEEDINGS{SRGea15,
author={van der Sanden, Bram and Reniers, Michel and Geilen, Marc and Basten, Twan and Jacobs, Johan and Voeten, Jeroen and Schiffelers, Ramon},
booktitle={2015 ACM/IEEE 18th International Conference on Model Driven Engineering Languages and Systems (MODELS)},
title={Modular model-based supervisory controller design for wafer logistics in lithography machines},
year={2015},
volume={},
number={},
pages={416-425},
doi={10.1109/MODELS.2015.7338273}
}