Robin Foot
will participate in the 10th Ergonomic Psychology Conference
in Lyon from July
9 to 12, 2019, as part of a symposium on "Mental Load in Risky Situations."
His presentation is entitled: The safety paradox of a safety system on trams. The cognitive hypothesis and ways of resolving this paradox: the Clermont-Ferrand experience.
The monitoring devices are designed to stop the tram in the event of driver failure. The driver must not hold the monitoring device for more than ten seconds or release it for more than two seconds, otherwise an audible alarm will sound and, if there is no change in the status of the device after two seconds, emergency braking will be activated.
The logic of this device is decoupled from the logic of driving. The driver is therefore in a classic situation of dual task, of attentional competition.
An INRS study showed that drivers adjusted their monitoring action to the release delay as a cognitive economy strategy.
In addition to the problem of occupational illnesses caused by the frequency of monitoring actions, this demonstrated that monitoring had a distracting effect on driving. Two fatal passenger accidents confirmed that monitoring compromises driving safety.
In Clermont-Ferrand, the transformation of vigilance both in terms of functionality (elimination of the delay in maintaining vigilance) and the form of the actuators made it possible to resolve this paradox of a safety system that compromised safety.
This transformation was monitored with a group of six drivers during three observation campaigns between June 2015 and November 2017 in three different standby configurations. These observations show a radical decrease in the average frequency of actions on the standby system, from 40 actions/minute in 2015 to less than one action per minute in 2017.
This decrease in frequency shows that actions on the dashboard are becoming neutral in relation to driving. This result was achieved by modifying both the functional logic and the shapes of the dashboard actuators.