Classification of Drivers' Workload Using Physiological Signals in Conditional Automation
The use of automation in cars is increasing. In future vehicles, drivers will no longer be in charge of the main driving task and may be allowed to perform a secondary task. However, they might be requested to regain control of the car if a hazardous situation occurs (i.e., conditionally automated d...
| Main Authors: | , , , , , , , |
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| Format: | Article |
| Language: | English |
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Frontiers Media S.A.
2021-02-01
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| Series: | Frontiers in Psychology |
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| Online Access: | https://www.frontiersin.org/articles/10.3389/fpsyg.2021.596038/full |
| _version_ | 1819050033472864256 |
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| author | Quentin Meteier Marine Capallera Simon Ruffieux Leonardo Angelini Omar Abou Khaled Elena Mugellini Marino Widmer Andreas Sonderegger |
| author_facet | Quentin Meteier Marine Capallera Simon Ruffieux Leonardo Angelini Omar Abou Khaled Elena Mugellini Marino Widmer Andreas Sonderegger |
| author_sort | Quentin Meteier |
| collection | DOAJ |
| description | The use of automation in cars is increasing. In future vehicles, drivers will no longer be in charge of the main driving task and may be allowed to perform a secondary task. However, they might be requested to regain control of the car if a hazardous situation occurs (i.e., conditionally automated driving). Performing a secondary task might increase drivers' mental workload and consequently decrease the takeover performance if the workload level exceeds a certain threshold. Knowledge about the driver's mental state might hence be useful for increasing safety in conditionally automated vehicles. Measuring drivers' workload continuously is essential to support the driver and hence limit the number of accidents in takeover situations. This goal can be achieved using machine learning techniques to evaluate and classify the drivers' workload in real-time. To evaluate the usefulness of physiological data as an indicator for workload in conditionally automated driving, three physiological signals from 90 subjects were collected during 25 min of automated driving in a fixed-base simulator. Half of the participants performed a verbal cognitive task to induce mental workload while the other half only had to monitor the environment of the car. Three classifiers, sensor fusion and levels of data segmentation were compared. Results show that the best model was able to successfully classify the condition of the driver with an accuracy of 95%. In some cases, the model benefited from sensors' fusion. Increasing the segmentation level (e.g., size of the time window to compute physiological indicators) increased the performance of the model for windows smaller than 4 min, but decreased for windows larger than 4 min. In conclusion, the study showed that a high level of drivers' mental workload can be accurately detected while driving in conditional automation based on 4-min recordings of respiration and skin conductance. |
| first_indexed | 2024-12-21T11:41:37Z |
| format | Article |
| id | doaj.art-9f0b3136582e409ea66d0ce5199ebe52 |
| institution | Directory Open Access Journal |
| issn | 1664-1078 |
| language | English |
| last_indexed | 2024-12-21T11:41:37Z |
| publishDate | 2021-02-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Psychology |
| spelling | doaj.art-9f0b3136582e409ea66d0ce5199ebe522022-12-21T19:05:18ZengFrontiers Media S.A.Frontiers in Psychology1664-10782021-02-011210.3389/fpsyg.2021.596038596038Classification of Drivers' Workload Using Physiological Signals in Conditional AutomationQuentin Meteier0Marine Capallera1Simon Ruffieux2Leonardo Angelini3Omar Abou Khaled4Elena Mugellini5Marino Widmer6Andreas Sonderegger7HumanTech Institute, University of Applied Sciences of Western Switzerland, Haute École Spécialisée de Suisse Occidentale, Fribourg, SwitzerlandHumanTech Institute, University of Applied Sciences of Western Switzerland, Haute École Spécialisée de Suisse Occidentale, Fribourg, SwitzerlandHumanTech Institute, University of Applied Sciences of Western Switzerland, Haute École Spécialisée de Suisse Occidentale, Fribourg, SwitzerlandHumanTech Institute, University of Applied Sciences of Western Switzerland, Haute École Spécialisée de Suisse Occidentale, Fribourg, SwitzerlandHumanTech Institute, University of Applied Sciences of Western Switzerland, Haute École Spécialisée de Suisse Occidentale, Fribourg, SwitzerlandHumanTech Institute, University of Applied Sciences of Western Switzerland, Haute École Spécialisée de Suisse Occidentale, Fribourg, SwitzerlandDepartment of Informatics, University of Fribourg, Fribourg, SwitzerlandBern University of Applied Sciences, Business School, Institute for New Work, Bern, SwitzerlandThe use of automation in cars is increasing. In future vehicles, drivers will no longer be in charge of the main driving task and may be allowed to perform a secondary task. However, they might be requested to regain control of the car if a hazardous situation occurs (i.e., conditionally automated driving). Performing a secondary task might increase drivers' mental workload and consequently decrease the takeover performance if the workload level exceeds a certain threshold. Knowledge about the driver's mental state might hence be useful for increasing safety in conditionally automated vehicles. Measuring drivers' workload continuously is essential to support the driver and hence limit the number of accidents in takeover situations. This goal can be achieved using machine learning techniques to evaluate and classify the drivers' workload in real-time. To evaluate the usefulness of physiological data as an indicator for workload in conditionally automated driving, three physiological signals from 90 subjects were collected during 25 min of automated driving in a fixed-base simulator. Half of the participants performed a verbal cognitive task to induce mental workload while the other half only had to monitor the environment of the car. Three classifiers, sensor fusion and levels of data segmentation were compared. Results show that the best model was able to successfully classify the condition of the driver with an accuracy of 95%. In some cases, the model benefited from sensors' fusion. Increasing the segmentation level (e.g., size of the time window to compute physiological indicators) increased the performance of the model for windows smaller than 4 min, but decreased for windows larger than 4 min. In conclusion, the study showed that a high level of drivers' mental workload can be accurately detected while driving in conditional automation based on 4-min recordings of respiration and skin conductance.https://www.frontiersin.org/articles/10.3389/fpsyg.2021.596038/fullautomated drivingclassificationdriverworkloadphysiologysecondary task |
| spellingShingle | Quentin Meteier Marine Capallera Simon Ruffieux Leonardo Angelini Omar Abou Khaled Elena Mugellini Marino Widmer Andreas Sonderegger Classification of Drivers' Workload Using Physiological Signals in Conditional Automation Frontiers in Psychology automated driving classification driver workload physiology secondary task |
| title | Classification of Drivers' Workload Using Physiological Signals in Conditional Automation |
| title_full | Classification of Drivers' Workload Using Physiological Signals in Conditional Automation |
| title_fullStr | Classification of Drivers' Workload Using Physiological Signals in Conditional Automation |
| title_full_unstemmed | Classification of Drivers' Workload Using Physiological Signals in Conditional Automation |
| title_short | Classification of Drivers' Workload Using Physiological Signals in Conditional Automation |
| title_sort | classification of drivers workload using physiological signals in conditional automation |
| topic | automated driving classification driver workload physiology secondary task |
| url | https://www.frontiersin.org/articles/10.3389/fpsyg.2021.596038/full |
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