Software Development

the FUNCTIONAL RESONANCE

  ANALYSIS METHOD


The FRAM Sandbox Facility

Extending the capabilities of the FMV


There is an increasing interest in utilising the FRAM approach for the analysis of what exactly is going on in complex sociotechnical systems in practical high hazard environments. There are, for example, a number of ongoing projects at the moment in aviation, self-driving vehicles and, of course, on the challenges of the COVID 19 pandemic for healthcare responses. But as well as these practical applications there is an increasing interest from the academic community, in extending and developing further, the underpinning concepts, as shown in the recent review (below)


These groups are thus interested in taking the modelling power of the FRAM approach to the next level. Their interests include exploring in more detail how interactions occur and how the effects of variability can be addressed and predicted more formally, as well as enabling dynamic visualisation of processes and the quantification of expected outcomes.

What makes this now more attractive, has been the development of a rigorous model checking methodology, the FRAM Model Interpreter, FMI (Hollnagel, E,) (www.safetysynthesis.com )

To support these developments the FRAM Model Visualiser has also been given extra facilities, which now include an option to use, what is essentially a laboratory sand box to provide research laboratory experimental facilities for different groups to utilise.


From time to time, it is planned to add additional features that are still under development and not officially released as part of the FMV Pro version, but may be made available to groups for the purposes of experimentation and feedback from the users.


Metadata

Building on the FMI functionality, the metadata feature in the FMV, now provides the ability to calculate metadata values as Functions are activated during the FMI cycles.


The manual details these here


The calculations are expressed as user defined equations that can reference other metadata keys, standard variables, standard mathematical functions, logic conditions, and mathematical operators. One or two resulting metadata values can then be expressed as a coloured visualisation within each function. The colours and value ranges can be customised by the user.

When you Ctrl-Click a Function, or select and press Ctrl-M, the metadata section will appear above the model in the visualiser window and display the extended features.


Key/Value pairs


The first two text boxes are for entering metadata as a list of key/value pairs, as is already available in the standard FMV Pro versions. A Key is entered in the first box shaded grey, but it will not be saved for the selected Function until a Value or an Equation is also entered for that Key. The corresponding Value is entered in the second text box.

When a Key is saved for a Function, It will be shown along with all saved Key names when any other Function is selected. As such, the Key names become common across all Functions. However, the corresponding Values are unique to each individual Function.

Key names can be used as Variable names and referenced in Equations if they start with a capital letter (this is to differentiate between Variables and mathematical functions).


Equations


To calculate the Value of a Key for a Function (when it is activated by the FMI) click the ‘=’ button and another text input box will appear for entering an equation.

Equations can contain Key names to reference other Values that appear above them in the same Function, or Standard Variables can be used to reference Values from upstream Functions, connected by couplings that are activated during the FMI cycles. This is explained in further sections.

To turn the equation off, click the ‘=’ button again (this is a toggle button) and the equation will disappear, it is still saved but will not be used to calculate the Value.

Functions/Variables List

The next section is a list of available mathematical functions and variables available for use in Equations. You can switch between these two types by using the Functions/Variables toggle buttons above the list. The Variables list is initially empty but will be populated as you create Keys and make selections within the model.


Display Results


The top colour range is used to display results in the inside top of each function, the bottom range in the inside bottom of each function. Click on any of the three main colour circles to change the colour. The intermediate colours are blended from the three main colours.

The number boxes below the colour ranges are used to convert the Values to the colour range for dsiplay.

The last two text boxes on the right labeled ‘Key 1’ and ‘Key 2’ are for selecting which of the Keys provide values for displaying the results, Key 1 for the top range and Key 2 for the bottom range.

FRAM Model Visualiser (FMV)

Model Building and Visualisation

It was clear from the very beginning that it would be very useful to have a software tool that could be used to build a model and also automatically could create a graphical representation of a FRAM model. After several attempts this tool is now available. It is called the FRAM Model Visualiser (FMV).

The FMV allows a user to build and edit a FRAM mode and to visualise it. The FMV is installed and run using Adobe Air, which can be download from the Adobe website http://get.adobe.com/air.

The current version  of the FMV (version 0.4.1, updated May 27, 2016) can be found here.

Instructions on how to use the FMV can be found here. The instructions now include a reference to a change log, where suggestions for improvements also can be submitted. A simple handbook for how to use the FMV to build a FRAM model can be found here. (Please note that the examples are taken from health care.)

A definition of the FMV data format can be found here.

Please provide feedback both about the FMV and the instructions. And share interesting examples.

The FMV has been developed and written by Rees Hill (http://www.zerprize.com). The FRAMily gratefully acknowledges this significant contribution.

Conditions of use

The FMV, regardless of version, is provided by the copyright holders and contributors “as is” and any express or implied warranties, including, but not limited to, the implied warranties of merchantability and fitness for a particular purpose are disclaimed. In no event shall the copyright holder or contributors be liable for any direct, indirect, incidental, special, exemplary, or consequential damages (including, but not limited to, procurement of substitute goods or services; loss of use, data, or profits; or business interruption) however caused and on any theory of liability, whether in contract, strict liability, or tort (including negligence or otherwise) arising in any way out of the use of this software, even if advised of the possibility of such damage.

The FMV is provided free of charge and must not be sold for commercial purposes in either the original or a repackaged form.



We are looking forward to seeing the results of using this new facility and seeing the range and scope of applications and studies significantly extended. Perhaps we will see some examples at the next FRAMily Workshop in Kyoto next year, COVID willing.

© Copyright Erik Hollnagel 2016. All Rights Reserved.