last update: March 23, 2012                [HOME]

DG308: Discrete Interaction Design


Prof. Dr. M. Rauterberg, Full Professor
Faculty Industrial Design, Designed Intelligence Group, Technical University Eindhoven
Time and location via email to all subscribed students.


This assignment need 56 hrs work in total, the number of weeks depends on the actual period length (min 7 weeks).

After following this assignment students should be able to:

  • specify the interaction structure of a new and so far unknown interactive product with one established formal specification method with Petri-Nets;
  • create a mid-fidelity prototype in PowerPoint (or Flash) based on this specification;
  • conduct a small usability test and translate the results as possible input for a re-design;
  • prepare and give several presentations (several mid-terms, and final);
  • write a report about the findings and results.

Previous Knowledge

  • basic programming knowledge in PowerPoint, Flash, or other methods
  • digital video recording and editing
  • planning and conducting a small usability test (formative evaluation)


The assignment will start with a short introduction to the "feel" of interactive products. The "look" is not covered by this assignment but for the "feel" part a formal specification method for interaction structures (Petri-Net) will be introduced. The students will apply this knowledge on a new design of a not yet existing interactive system or product for which a usability test can be conducted.

The first part of the assignment consists of creating a new interactive system or product idea (presented at first mid-term meeting), develop the discrete interaction structure for the planned functionality with Petri-Nets as the formal specification method, and present the final specification document/diagram at the second mid-term meeting.

The second part of this assignment consists of implementing the specified discrete interaction structure in a mid-fidelity prototype (PowerPoint or Flash), and test the result with several users. Based on the recorded users' reactions/comments, recommendations for a possible re-design have to be drawn. The main results of the user tests based on the final prototype are presented in the final meeting.

Students will learn to use a formal specification methods as input for the implementation of a mid-fidelity prototype. They will gain hands-on experience in (1) using a formal specification as input for creating a prototype, and (2) planning and conducting an empirical evaluation. They will experience how to optimise the trade-offs inherent in conducting prototyping and usability testing under 'real-life' constraints.

Literature is provided through this web-page (see below). Additional information throughout the assignment will be provided via the assignment emails distribution list DA301 (make sure that your email address is on this list!).

Assignment work

The feedback for this assignment will be determined by the work done on the set of deliverables (Dx; see below). Each deliverable (Dx) will cover a number of steps relevant for planning, applying and conducting a combination of formal and empirical methods. Furthermore, they will include discussions about the trade-offs of the decisions taken and the validity of the findings of the evaluation. Feedback will be determined based on the rigour with which the work is done, whether relevant concepts discussed in the assignment are embedded in the work and the report, and extra initiative to ensure good quality of work.

Deliverables [Dx] Date due

Description of the idea and purpose of the new interactive product (200-500 words)
[included in the final

2nd meeting

A complete specification of the new discrete interaction structure described in a document/diagram (with at least 20 different user actions/ functions and at least 10 different system states)
[included in the final report].

3rd meeting
All mid-term presentations in electronic form
      [D1: delivered as PPT file].
2nd-5th meetings

Mid-Fidelity Prototype (in case of an updated specification of the interaction structure, this updated document as well with a short description of what and why the changes were made; if you created more than one prototype, each version has to be delivered)
[design description included in the final report].
[D2: executable program file, eg. PPT or FLASH (plus source code)]


Description of the user test (formative evaluation, number of  test subjects = 4) including users' profiles, task(s) description, results and recommendations for re-design; each user test has to be documented via video recording including audio records of the users' comments (e.g., via screen capture program Camtasia Studio, etc.)
included in  the final report: (1) description of task(s), (2) user profile, (3) results, and (4) conclusions for possible re-design];
[D3: in addition 4 video files of user tests including audio of user comments].


Final presentation in electronic form  
[D4: delivered as PPT file]


Final report in electronic form  with all parts (incl. both Petri Nets) as specified above
[D5: delivered as DOC, RTF or PDF file] according the proposed structure and format (see Report Writing Guide)


D6: a CD (no auto run!) with all deliverables (D1) - (D5) per individual student handed in to the assignor's pigeonhole (HG 2.33), secretariat (HG 2.34), or himself (HG 2.36).

two days after final

Assignment schedule




Background material


Introduction in the specification methods Petri-Nets
lecture-1 [PPT] [PDF]    obligatory

Students will be grouped in teams of 3-4 students.

Lectures from others:
Bruce Powel Douglass (2004)
Finite State Machines (FSM):
what is a state?       [part 1]    obligatory
what is a transition? [part 2]    obligatory
advanced topics       [part 3]    voluntarily

all relevant literature to be familiar with

Reisig, W. (1992),  A Primer in Petri Net Design. Springer. [ISBN: 0387520449]

optional extra readings:
Harel (1987) Statecharts.
Murata (1989) Petri Nets.
Balbo et al (2000) Petri Nets Tutorial.
Saldhana and Shatz (2000) UML and Petri nets.

2nd meeting Each student team (3-4) presents description of the idea and proposed functionality of a new, non existing product.


Petri Nets World [overview] [tools]

* Yasper-Tool [download]
* WoPed-Tool [download]
3rd meeting Each student team (3-4) presents a description of the designed discrete interaction structure in form of a Petri net.

Each team will be split into 1-2 students.

optional extra readings:
how to design the perceivable part ("look") of the interface see lecture-2 and -3 as well as the additional readings at DA308 for discrete interaction design 2.

4th meeting

Presentation of each student team.

Examples in PPT: Example-1, Example-2

Example in FLASH: Example-1

The final part "user testing" will be done individually.

Engelberg & Seffah (2002)
Mid-Fidelity Prototyping.

how to perform a 'formative evaluation'
why 4 test subjects? read NIELSEN!

optional extra readings:
How to do a Usability test!
Usability Testing
Thinking-Aloud Method

Capture the test user interaction with a freeware screen capture program! and include the audio records of the user;
you can download the trial version Camtasia Studio for screen capturing during the usability tests; describe the results in a usability report.

final meeting

Presentation of each individual student about the working prototype plus the outcomes of the formative evaluation.

documention in a video clip as 'highlight tape'


Assignors Feedback to Student

Students will be working in 3-4 person teams till mid-term presentation; for the second part of this assignment till final presentation each student works individually; s/he will be graded based on the quality of the written reports/documents and the presentation given using a 4 point grading scale [“not done”= insufficient, “done”= sufficient, “well done”= above average, “very well done”= very good] and in constructive written feedback via the assignment feedback form.