A Formal Approach to Connectibility Affordances

Andrew J. Abbate, Ellen J. Bass
2019 IEEE Transactions on Human-Machine Systems  
Connectibility affordances, or opportunities for a user to establish input/output cable connections, can be critical to the safety and usability of complex systems. To support model-based analyses, this research introduces a formal approach: Connectibility Affordance VErification, Modeling, and ENumeration (CAVE-MEN). CAVEMEN is applicable to a human-environment system encompassing physical entities with specified properties, a user with specified motor abilities, and connectibility affordance
more » ... nstances involving different combinations of source-target connections. The modeling technique leverages object-oriented principles to define one instance of a connectibility affordance with respect to one unique combination of connection sources and targets. An inspection technique supports the enumeration of connectibility affordance instances that are desired (supporting a correct connection) and undesired (supporting an incorrect connection). A model checking technique aids in verifying accuracy, meaning the user can actualize desired affordance instances, and robustness, meaning undesired affordance instances never emerge. An XML-based grammar, a model checking syntax translation tool, and a linear temporal logic specification of accuracy and robustness support the analyses. We demonstrate CAVEMEN with a pacemaker system case study. The inspection aids in identifying nine desired and 18 undesired instances of chamber-port connectibility. The trace evaluation shows that accuracy and robustness depends on whether an entity property of interest can change in the environmental context. These results indicate that CAVEMEN shows promise for analyzing connectibility affordances of a safety-critical system. and Informatics, and an Affiliate Professor with the Drexel University's School of Biomedical Engineering, Science and Health Systems. She has more than 30 years of human-centered systems engineering research and design experience in air transportation, healthcare, and other domains and the focus of her research is to develop theories of human performance, quantitative modeling methodologies, and associated analysis methods that can be used to evaluate human-system interaction in the context of total system performance.
doi:10.1109/thms.2018.2886265 fatcat:xlpwxwzdvjhndb2heo4pw6xbyy