Emma Tivesten - Academia.edu (original) (raw)
Papers by Emma Tivesten
Transportation Research Part F-traffic Psychology and Behaviour, May 1, 2023
IEEE Transactions on Human-Machine Systems
Existing research on control-transitions from automated driving (AD) to manual driving mainly ste... more Existing research on control-transitions from automated driving (AD) to manual driving mainly stems from studies in virtual settings. There is a need for studies conducted in real settings to better understand the impacts of increasing vehicle automation on traffic safety. This study aims specifically to understand how drivers respond to takeover requests (TORs) in real traffic by investigating the associations between 1) where drivers look when receiving the TOR, 2) repeated exposure to TORs, and 3) the drivers' response process. In total, thirty participants were exposed to four TORs after about 5-6 min of driving with AD on public roads. While in AD, participants could choose to engage in non-driving-related tasks (NDRTs). When they received the TOR, for 38% of TORs, participants were already looking on path. For those TORs where drivers looked off path at the time of the TOR, the off-path glance was most commonly towards an NDRT item. Then, for 72% of TORs (independent on gaze direction), drivers started their response process to the TOR by looking towards the instrument cluster before placing their hands on the steering wheel and their foot on the accelerator pedal, and deactivating automation. Both timing and order of these actions varied among participants, but all participants deactivated AD within 10 s from the TOR. The drivers' gaze direction at the TOR had a stronger association with the response process than the repeated exposure to TORs did. Drivers can respond to TORs in real traffic. However, the response should be considered as a sequence of actions that requires a certain amount of time.
The purpose of this report is to study some types of possible head impact surfaces in side collis... more The purpose of this report is to study some types of possible head impact surfaces in side collision and to consider different injuries, tolerance levels and criteria. Work also included evaluation of new method of testing interior fittings in automotive environment suggested by the NHTSA (National Highway Traffic Safety Administration). The original method comprised a FMH (Free Motion Headform) head and a propulsion unit. FMH is a modified HIII head with the nose removed and the back of the head replaced by a steel plate. The head is meant to fly freely before impact at a speed of 15 mph (6.7 m/s). Since only the FMH head was accessible, free fall was used to accomplish the free flying motion. Two alternative methods were built with the FMH-head assembled on a HybridIII neck. The purpose was to get an idea of rotational acceleration in a typical side impact situation. The rotational acceleration is between 2000 and 4000 rad/s2. It was also interesting to study the effect on rotatio...
L'invention porte sur le systeme de declenchement d'un dispositif de securite associe a u... more L'invention porte sur le systeme de declenchement d'un dispositif de securite associe a une pedale d'un vehicule, et comprenant un bras de pedale (2), une tige poussoir (8), reliant le bras de pedale (2) a des moyens (9) concus pour agir sur le bras de pedale (2), un moyen d'action (6, 7, 10; 21; 31) desolidarisant la tige (8) du bras de pedale (2) et un detecteur (14, 15; 21; 31) declenchant le susdit moyen d'action (6, 7, 10; 21; 31) en cas de detection de circonstances correspondant sensiblement a celles d'une collision. L'invention se caracterise en ce que ledit detecteur (14, 15; 21; 31) et ledit moyen d'action (6, 7, 10; 21; 31) sont concus pour desolidariser la tige (8) du bras de pedale (2) avant qu'aucune autre partie du moteur ou du compartiment moteur du vehicule n'agisse sur la tige (8). Cette invention qui porte egalement sur un procede lie a la liberation de la tige (8) consiste donc en un dispositif associe a une pedale s'ap...
Social Science Research Network, 2022
Human Factors: The Journal of the Human Factors and Ergonomics Society
Objective This study aims to understand drivers’ visual attention before and after take-over requ... more Objective This study aims to understand drivers’ visual attention before and after take-over requests during automated driving (AD), when the vehicle is fully responsible for the driving task on public roads. Background Existing research on transitions of control from AD to manual driving has mainly focused on take-over times. Despite its relevance for vehicle safety, drivers’ visual attention has received little consideration. Method Thirty participants took part in a Wizard of Oz study on public roads. Drivers’ visual attention was analyzed before and after four take-over requests. Visual attention during manual driving was also recorded to serve as a baseline for comparison. Results During AD, the participants showed reduced visual attention to the forward road and increased duration of single off-road glances compared to manual driving. In response to take-over requests, the participants looked away from the forward road toward the instrument cluster. Levels of visual attention ...
Transportation Research Part F: Traffic Psychology and Behaviour, 2022
Real world data on driver behavior in normal driving and critical situations are essential for ca... more Real world data on driver behavior in normal driving and critical situations are essential for car safety development. Data collection and analysis methods that provide insight into the prevalence of crash contributing factors (e.g., drowsiness, distraction) and causation mechanisms are valuable when making priorities and selecting countermeasure principles. This thesis investigates different analysis methods applied to real world data from three sources: a crash mail survey, insurance claims, and naturalistic driving. Several analysis methods were investigated, including: adjusting for nonresponse in a crash mail survey, analyzing narratives provided by the involved road users in a crash, and investigating causation mechanisms based on video recordings of critical situations. Naturalistic driving data from whole trips were analyzed to investigate the influence of driving context (e.g., turning, other vehicles, speed) on drivers’ eye glance behavior and their exposure to visual-manu...
Human factors, Jan 10, 2018
The aim of this study was to understand how to secure driver supervision engagement and conflict ... more The aim of this study was to understand how to secure driver supervision engagement and conflict intervention performance while using highly reliable (but not perfect) automation. Securing driver engagement-by mitigating irony of automation (i.e., the better the automation, the less attention drivers will pay to traffic and the system, and the less capable they will be to resume control) and by communicating system limitations to avoid mental model misconceptions-is a major challenge in the human factors literature. One hundred six drivers participated in three test-track experiments in which we studied driver intervention response to conflicts after driving highly reliable but supervised automation. After 30 min, a conflict occurred wherein the lead vehicle cut out of lane to reveal a conflict object in the form of either a stationary car or a garbage bag. Supervision reminders effectively maintained drivers' eyes on path and hands on wheel. However, neither these reminders nor...
SAE Technical Paper Series, 2006
One way of avoiding crashes or mitigating the consequences of a crash is to apply an autonomous b... more One way of avoiding crashes or mitigating the consequences of a crash is to apply an autonomous braking system. Quantifying the benefit of such a system in terms of injury reduction is a challenge. At the same time it is a fundamental input into the vehicle development process. This paper describes a method to estimate the effectiveness of reducing speed prior to impact. A holistic view of quantifying the benefit is presented, based on existing real life crash data and basic dynamic theories. It involves a systematic and new way of examining accident data in order to extract information concerning pre-crash situations. One problem area when implementing collision mitigation systems is being able to achieve sufficient target discrimination. The results from the case study highlight frontal impact situations from real world accident data that have the greatest potential in terms of improving accident outcome. One of the first stages in the development of forward dectection driver supp...
Attention to injuries to foot, ankle and tibia is becoming increasingly focused as safety improve... more Attention to injuries to foot, ankle and tibia is becoming increasingly focused as safety improvements are made in other areas. As our knowledge increases, views concerning the factors that cause leg injuries become more varied. This paper presents Volvo's view on the subject and focuses on four main factors: Geometry, Pedals, Acceleration and Intrusion. The risk of injury is believed to be an accumulation of these factors. In order to achieve significant improvements in the area of leg injuries, it is therefore necessary to address all factors. [A] For the covering abstract, see IRRD 896528.
Adaptive Cruise Control (ACC) and Forward Collision Warning (FCW) have been shown to have a posit... more Adaptive Cruise Control (ACC) and Forward Collision Warning (FCW) have been shown to have a positive effect on safety-related measures despite a general increase in secondary task involvement. To understand this effect, this study examined the relationship between drivers glance locations and ACC hard braking or FCW events when ACC is active. The study analyzed naturalistic driving on motorways where the car remained in the same lane. Four subsets of driving segments were included: ACC braking (peak deceleration ≥ 3 m/s2), FCW+ACC (driving with ACC when a forward collision warning was issued) ACC maintaining speed, and Driver braking without ACC or FCW. The results indicate that although drivers do take their eyes off path more when using ACC, this conclusion seems to be valid only in non-critical (baseline-similar) situations. Drivers showed a steady increase in %EyesOnPath well before critical situations, resulting in 95% EyesOnPath both at the onset of ACC braking and at the onse...
Transportation Research Part F: Traffic Psychology and Behaviour
IET Intelligent Transport Systems
IEEE Transactions on Intelligent Transportation Systems
Automation aftereffects (i.e., degraded manual driving performance, delayed responses, and more a... more Automation aftereffects (i.e., degraded manual driving performance, delayed responses, and more aggressive avoidance maneuvers) have been found in driving simulator studies. In addition, longer automation duration seems to result in more severe aftereffects, compared to shorter duration. The extent to which these findings generalize to real-world driving is currently unknown. The present study investigated how automation duration affects drivers' takeover response quality and driving performance in a road-work zone. Seventeen participants followed a lead vehicle on test track. They encountered the road-work zone four times: two times while driving manually, and after a short and a long automation duration. The takeover request was issued before the lead vehicle changed lane to reveal the road-work zone. After both short and long automation durations, all drivers deactivated automation well ahead of the road-work zone. Compared to manual, drivers started their steering maneuvers earlier or at similar times after automation (independently of duration), and none of the drivers crashed. However, slight increases in vehicle speed and accelerations were observed after exposure to automation. In sum, the present study did not observe as large automation aftereffects on the test track as previously found in driving simulator studies. The extent to which these results are a consequence of a more realistic test environment, or due to the duration between the timings for the takeover request and the conflict appearance, is still unknown.
Transportation Research Part F-traffic Psychology and Behaviour, May 1, 2023
IEEE Transactions on Human-Machine Systems
Existing research on control-transitions from automated driving (AD) to manual driving mainly ste... more Existing research on control-transitions from automated driving (AD) to manual driving mainly stems from studies in virtual settings. There is a need for studies conducted in real settings to better understand the impacts of increasing vehicle automation on traffic safety. This study aims specifically to understand how drivers respond to takeover requests (TORs) in real traffic by investigating the associations between 1) where drivers look when receiving the TOR, 2) repeated exposure to TORs, and 3) the drivers' response process. In total, thirty participants were exposed to four TORs after about 5-6 min of driving with AD on public roads. While in AD, participants could choose to engage in non-driving-related tasks (NDRTs). When they received the TOR, for 38% of TORs, participants were already looking on path. For those TORs where drivers looked off path at the time of the TOR, the off-path glance was most commonly towards an NDRT item. Then, for 72% of TORs (independent on gaze direction), drivers started their response process to the TOR by looking towards the instrument cluster before placing their hands on the steering wheel and their foot on the accelerator pedal, and deactivating automation. Both timing and order of these actions varied among participants, but all participants deactivated AD within 10 s from the TOR. The drivers' gaze direction at the TOR had a stronger association with the response process than the repeated exposure to TORs did. Drivers can respond to TORs in real traffic. However, the response should be considered as a sequence of actions that requires a certain amount of time.
The purpose of this report is to study some types of possible head impact surfaces in side collis... more The purpose of this report is to study some types of possible head impact surfaces in side collision and to consider different injuries, tolerance levels and criteria. Work also included evaluation of new method of testing interior fittings in automotive environment suggested by the NHTSA (National Highway Traffic Safety Administration). The original method comprised a FMH (Free Motion Headform) head and a propulsion unit. FMH is a modified HIII head with the nose removed and the back of the head replaced by a steel plate. The head is meant to fly freely before impact at a speed of 15 mph (6.7 m/s). Since only the FMH head was accessible, free fall was used to accomplish the free flying motion. Two alternative methods were built with the FMH-head assembled on a HybridIII neck. The purpose was to get an idea of rotational acceleration in a typical side impact situation. The rotational acceleration is between 2000 and 4000 rad/s2. It was also interesting to study the effect on rotatio...
L'invention porte sur le systeme de declenchement d'un dispositif de securite associe a u... more L'invention porte sur le systeme de declenchement d'un dispositif de securite associe a une pedale d'un vehicule, et comprenant un bras de pedale (2), une tige poussoir (8), reliant le bras de pedale (2) a des moyens (9) concus pour agir sur le bras de pedale (2), un moyen d'action (6, 7, 10; 21; 31) desolidarisant la tige (8) du bras de pedale (2) et un detecteur (14, 15; 21; 31) declenchant le susdit moyen d'action (6, 7, 10; 21; 31) en cas de detection de circonstances correspondant sensiblement a celles d'une collision. L'invention se caracterise en ce que ledit detecteur (14, 15; 21; 31) et ledit moyen d'action (6, 7, 10; 21; 31) sont concus pour desolidariser la tige (8) du bras de pedale (2) avant qu'aucune autre partie du moteur ou du compartiment moteur du vehicule n'agisse sur la tige (8). Cette invention qui porte egalement sur un procede lie a la liberation de la tige (8) consiste donc en un dispositif associe a une pedale s'ap...
Social Science Research Network, 2022
Human Factors: The Journal of the Human Factors and Ergonomics Society
Objective This study aims to understand drivers’ visual attention before and after take-over requ... more Objective This study aims to understand drivers’ visual attention before and after take-over requests during automated driving (AD), when the vehicle is fully responsible for the driving task on public roads. Background Existing research on transitions of control from AD to manual driving has mainly focused on take-over times. Despite its relevance for vehicle safety, drivers’ visual attention has received little consideration. Method Thirty participants took part in a Wizard of Oz study on public roads. Drivers’ visual attention was analyzed before and after four take-over requests. Visual attention during manual driving was also recorded to serve as a baseline for comparison. Results During AD, the participants showed reduced visual attention to the forward road and increased duration of single off-road glances compared to manual driving. In response to take-over requests, the participants looked away from the forward road toward the instrument cluster. Levels of visual attention ...
Transportation Research Part F: Traffic Psychology and Behaviour, 2022
Real world data on driver behavior in normal driving and critical situations are essential for ca... more Real world data on driver behavior in normal driving and critical situations are essential for car safety development. Data collection and analysis methods that provide insight into the prevalence of crash contributing factors (e.g., drowsiness, distraction) and causation mechanisms are valuable when making priorities and selecting countermeasure principles. This thesis investigates different analysis methods applied to real world data from three sources: a crash mail survey, insurance claims, and naturalistic driving. Several analysis methods were investigated, including: adjusting for nonresponse in a crash mail survey, analyzing narratives provided by the involved road users in a crash, and investigating causation mechanisms based on video recordings of critical situations. Naturalistic driving data from whole trips were analyzed to investigate the influence of driving context (e.g., turning, other vehicles, speed) on drivers’ eye glance behavior and their exposure to visual-manu...
Human factors, Jan 10, 2018
The aim of this study was to understand how to secure driver supervision engagement and conflict ... more The aim of this study was to understand how to secure driver supervision engagement and conflict intervention performance while using highly reliable (but not perfect) automation. Securing driver engagement-by mitigating irony of automation (i.e., the better the automation, the less attention drivers will pay to traffic and the system, and the less capable they will be to resume control) and by communicating system limitations to avoid mental model misconceptions-is a major challenge in the human factors literature. One hundred six drivers participated in three test-track experiments in which we studied driver intervention response to conflicts after driving highly reliable but supervised automation. After 30 min, a conflict occurred wherein the lead vehicle cut out of lane to reveal a conflict object in the form of either a stationary car or a garbage bag. Supervision reminders effectively maintained drivers' eyes on path and hands on wheel. However, neither these reminders nor...
SAE Technical Paper Series, 2006
One way of avoiding crashes or mitigating the consequences of a crash is to apply an autonomous b... more One way of avoiding crashes or mitigating the consequences of a crash is to apply an autonomous braking system. Quantifying the benefit of such a system in terms of injury reduction is a challenge. At the same time it is a fundamental input into the vehicle development process. This paper describes a method to estimate the effectiveness of reducing speed prior to impact. A holistic view of quantifying the benefit is presented, based on existing real life crash data and basic dynamic theories. It involves a systematic and new way of examining accident data in order to extract information concerning pre-crash situations. One problem area when implementing collision mitigation systems is being able to achieve sufficient target discrimination. The results from the case study highlight frontal impact situations from real world accident data that have the greatest potential in terms of improving accident outcome. One of the first stages in the development of forward dectection driver supp...
Attention to injuries to foot, ankle and tibia is becoming increasingly focused as safety improve... more Attention to injuries to foot, ankle and tibia is becoming increasingly focused as safety improvements are made in other areas. As our knowledge increases, views concerning the factors that cause leg injuries become more varied. This paper presents Volvo's view on the subject and focuses on four main factors: Geometry, Pedals, Acceleration and Intrusion. The risk of injury is believed to be an accumulation of these factors. In order to achieve significant improvements in the area of leg injuries, it is therefore necessary to address all factors. [A] For the covering abstract, see IRRD 896528.
Adaptive Cruise Control (ACC) and Forward Collision Warning (FCW) have been shown to have a posit... more Adaptive Cruise Control (ACC) and Forward Collision Warning (FCW) have been shown to have a positive effect on safety-related measures despite a general increase in secondary task involvement. To understand this effect, this study examined the relationship between drivers glance locations and ACC hard braking or FCW events when ACC is active. The study analyzed naturalistic driving on motorways where the car remained in the same lane. Four subsets of driving segments were included: ACC braking (peak deceleration ≥ 3 m/s2), FCW+ACC (driving with ACC when a forward collision warning was issued) ACC maintaining speed, and Driver braking without ACC or FCW. The results indicate that although drivers do take their eyes off path more when using ACC, this conclusion seems to be valid only in non-critical (baseline-similar) situations. Drivers showed a steady increase in %EyesOnPath well before critical situations, resulting in 95% EyesOnPath both at the onset of ACC braking and at the onse...
Transportation Research Part F: Traffic Psychology and Behaviour
IET Intelligent Transport Systems
IEEE Transactions on Intelligent Transportation Systems
Automation aftereffects (i.e., degraded manual driving performance, delayed responses, and more a... more Automation aftereffects (i.e., degraded manual driving performance, delayed responses, and more aggressive avoidance maneuvers) have been found in driving simulator studies. In addition, longer automation duration seems to result in more severe aftereffects, compared to shorter duration. The extent to which these findings generalize to real-world driving is currently unknown. The present study investigated how automation duration affects drivers' takeover response quality and driving performance in a road-work zone. Seventeen participants followed a lead vehicle on test track. They encountered the road-work zone four times: two times while driving manually, and after a short and a long automation duration. The takeover request was issued before the lead vehicle changed lane to reveal the road-work zone. After both short and long automation durations, all drivers deactivated automation well ahead of the road-work zone. Compared to manual, drivers started their steering maneuvers earlier or at similar times after automation (independently of duration), and none of the drivers crashed. However, slight increases in vehicle speed and accelerations were observed after exposure to automation. In sum, the present study did not observe as large automation aftereffects on the test track as previously found in driving simulator studies. The extent to which these results are a consequence of a more realistic test environment, or due to the duration between the timings for the takeover request and the conflict appearance, is still unknown.