Integrating User Design and Formal Models within PVSio-Web

Abstract

Creating formal models of interactive systems has wide reaching benefits, not only for verifying lowlevel correctness, but also as a tool for ensuring user interfaces behave logically and consistently. Despite this, tools for designing user experiences and tools for creating and working with formal models are typically distinctly separate systems. This work aims to bridge this divide by allowing the generation of state machine diagrams and formal models via a simple, interactive prototyping tool that mirrors the basic functionality of many modern digital prototyping applications.

Formal Modelling as a Component of User Centred Design

“…The steps of the method use the following tools provided by the PVSio-web toolkit: PVS [16] to develop and analyse the model; PVSio [15] to check its plausibility; the PVSio-web Storyboard Editor [18] to develop the initial sketch; the PVSio-web Prototype Builder [12] to produce an interactive prototype based on the PVS model. PVSio-web is a web-based environment that enables the creation of interactive prototypes based on executable PVS specifications.…”

“…A PVS function is now illustrated that specifies the behaviour of the pill dispenser when the operator enters new patient details (Listing 1.3). The specification of the function includes identification of the actions that are visible (lines 5-7), the fields that are visible (lines [16][17][18], the fields that are selected (none in this case, see line 19) and the field that is entered (line 20). Within the mode, specified by the mode attribute of state, fields can be entered (as discussed below, and see definition of enter in Listing 1.5).…”

“…On the other hand pressing confirm also updates the patient database (if any changes have been made in the patient details screen) and produces the patient list screen (see lines [7][8][9][10][11][12][13][14][15][16][17][18]. Furthermore the sketch indicates that the confirm action is only permitted if all the relevant fields have been selected and entered.…”

“…Furthermore the sketch indicates that the confirm action is only permitted if all the relevant fields have been selected and entered. In this case the patient database is updated with the temporary patient record (st2'temp patient) using the function p insert which inserts the patient into the database (lines [16][17][18]. The database is ordered and the insertion either replaces an existing record or inserts the record in the right place in the list.…”

Towards a Simulation-Based Medical Education Platform for PVSio-Web

“…developed in an open-source framework, our SBME allows customization and expansion by other developers. Moreover, recent developments in PVSio-Web facilitate the implementation of medical device simulations by non-experts in formal modelling [24].…”