Publications by authors named "Franck Mars"

Shared spaces are urban areas without physical separation between motorised and non-motorised users. Previous research has suggested that it is difficult for users to appropriate these spaces and that the advent of self-driving cars could further complicate interactions. It is therefore important to study the perception of these spaces from the users' perspectives to determine which conditions may promote their acceptance of the vehicles.

View Article and Find Full Text PDF

Taking a motor planning perspective, this study investigates whether haptic force cues displayed on the steering wheel are more effective than visual cues in signaling the direction of an upcoming lane change. Licensed drivers drove in a fixed-base driving simulator equipped with an active steering system for realistic force feedback. They were instructed to make lane changes upon registering a directional cue.

View Article and Find Full Text PDF

Recent research indicates that installing shoulders on rural roads for safety purposes causes drivers to steer further inside on right bends and thus exceed lane boundaries. The present simulator study examined whether continuous rather than broken edge-line delineation would help drivers to keep their vehicles within the lane. The results indicated that continuous delineation significantly impacts the drivers' gaze and steering trajectories.

View Article and Find Full Text PDF
Article Synopsis
  • The study aims to utilize advanced computational tools to improve the management of multiple sclerosis (MS), particularly for relapsing-remitting MS (RRMS) patients.
  • Researchers analyzed phase 3 clinical trial data to compare the effectiveness of peg-interferon beta-1a against a placebo using various measures of disease activity.
  • They created a prototype decision support system called MS Vista that personalizes treatment efficacy information for patients and enhances communication between healthcare providers and patients.
View Article and Find Full Text PDF
Article Synopsis
  • Machine learning (ML) models have great potential to improve healthcare by aiding in diagnoses, treatment decisions, and predicting health outcomes, but their adoption is limited.
  • A key barrier to deploying ML in healthcare is the need for transparency and accuracy in the data used for training models, as physicians want clear reasoning behind the decisions of these models.
  • The paper proposes a hybrid method that combines human expertise with machine learning, emphasizing the use of quality data and physician involvement, which has shown to enhance the performance of predictive models in healthcare.
View Article and Find Full Text PDF

The installation of shoulders on rural roads to create more forgiving roads encourages drivers to cut corners on right-hand bends, but the underlying mechanisms are poorly understood. Since eye movements and steering control are closely coupled, this study investigated how the presence of a shoulder influences drivers' gaze strategies. To this end, eighteen drivers negotiated right-hand bends with and without a shoulder on a simulated rural road.

View Article and Find Full Text PDF

Autonomous navigation becomes complex when it is performed in an environment that lacks road signs and includes a variety of users, including vulnerable pedestrians. This article deals with the perception of collision risk from the viewpoint of a passenger sitting in the driver's seat who has delegated the total control of their vehicle to an autonomous system. The proposed study is based on an experiment that used a fixed-base driving simulator.

View Article and Find Full Text PDF

When manually steering a car, the driver's visual perception of the driving scene and his or her motor actions to control the vehicle are closely linked. Since motor behaviour is no longer required in an automated vehicle, the sampling of the visual scene is affected. Autonomous driving typically results in less gaze being directed towards the road centre and a broader exploration of the driving scene, compared to manual driving.

View Article and Find Full Text PDF

During highly automated driving, drivers no longer physically control the vehicle but they might need to monitor the driving scene. This is true for SAE level 2, where monitoring the external environment is required; it is also true for level 3, where drivers must react quickly and safely to a take-over request. Without such monitoring, even if only partial, drivers are considered out-of-the-loop (OOTL) and safety may be compromised.

View Article and Find Full Text PDF

When negotiating bends car drivers perform gaze polling: their gaze shifts between guiding fixations (GFs; gaze directed 1-2 s ahead) and look-ahead fixations (LAFs; longer time headway). How might this behavior change in autonomous vehicles where the need for constant active visual guidance is removed? In this driving simulator study, we analyzed this gaze behavior both when the driver was in charge of steering or when steering was delegated to automation, separately for bend approach (straight line) and the entry of the bend (turn), and at various speeds. The analysis of gaze distributions relative to bend sections and driving conditions indicate that visual anticipation (through LAFs) is most prominent before entering the bend.

View Article and Find Full Text PDF

The recent development of motorcycle simulators has made it possible to study rider behavior in safe conditions. However, their use still raises validity issues. Our study examined how riders' steering and gaze behaviors and subjective experience are influenced by motorcycle roll tilt and reverse steering, which are considered to be essential factors in real-life motorcycle riding.

View Article and Find Full Text PDF

Objective: To present a structured, narrative review highlighting research into human perceptual-motor coordination that can be applied to automated vehicle (AV)-human transitions.

Background: Manual control of vehicles is made possible by the coordination of perceptual-motor behaviors (gaze and steering actions), where active feedback loops enable drivers to respond rapidly to ever-changing environments. AVs will change the nature of driving to periods of monitoring followed by the human driver taking over manual control.

View Article and Find Full Text PDF

When guiding a remote collaborator in a virtual environment, people often take an addressee-perspective, which may have a high cognitive cost. In order to improve collaborative virtual environments, a better understanding of how operators share spatial information is needed. This work aimed to study the cognitive workload linked to spatial statements production in situations in which the relative positions of speaker, addressee and target were varied.

View Article and Find Full Text PDF

This study investigated human-machine cooperation when driving with different degrees of a shared control system. By means of a direct intervention on the steering wheel, shared control systems partially correct the vehicle's trajectory and, at the same time, provide continuous haptic guidance to the driver. A crucial point is to determine the optimal level of steering assistance for effective cooperation between the two agents.

View Article and Find Full Text PDF

It has long been held that steering a vehicle is subserved by two distinct visual processes, a compensatory one for maintaining lane position and an anticipatory one for previewing the curvature of the upcoming road. In this study, we investigated the robustness of these two steering control processes by systematically degrading their visual inputs. Performance was measured at the level of vehicle position and at the level of the actions on the steering wheel.

View Article and Find Full Text PDF

Current theories on the role of visuomotor coordination in driving agree that active sampling of the road by the driver informs the arm-motor system in charge of performing actions on the steering wheel. Still under debate, however, is the nature of visual cues and gaze strategies used by drivers. In particular, the tangent point hypothesis, which states that drivers look at a specific point on the inside edge line, has recently become the object of controversy.

View Article and Find Full Text PDF

Unlabelled: Some driving devices are designed to prevent road departures. One such device, motor priming (MP), provides small pulses to the steering wheel towards the lane centre, without correcting the trajectory itself. Compared with the other lane departure warning systems, its higher efficacy has been demonstrated; it is hypothesised that this relies on the action of haptic cues at the sensorimotor level (Navarro, J.

View Article and Find Full Text PDF

Previous research has shown that a device called "motor priming" (MP) was more effective than other lane departure warning systems. MP prompts drivers to take action by means of small asymmetric oscillations of the steering wheel. The first objective of this experiment was to provide a deeper understanding of MP mechanisms through a series of comparisons with other haptic and auditory systems.

View Article and Find Full Text PDF

This study investigated the link between drivers' gaze positioning and steering behavior when negotiating bends. This was conducted by directing the driver's point of gaze toward a target situated in the vicinity of the tangent point (TP), a region known to attract a significant amount of ocular fixations and thought to provide some useful input for anticipatory steering (M. F.

View Article and Find Full Text PDF

Objective: This paper's first objective is to determine whether motor priming assistance (consisting of directional steering wheel vibrations) can be of some benefit compared with more traditional auditory (lateralized sound) or vibratory (symmetric steering wheel oscillation) warning devices. We hypothesize that warning devices favor driving situation diagnosis, whereas motor priming can improve the initiation of action even further. Another objective is to assess the possible benefits of using multimodal information by combining auditory warning with simple steering wheel vibration or motor priming.

View Article and Find Full Text PDF

Previous studies demonstrated that sensory stimulation could differentially affect the subjective vertical (SV) and the subjective body orientation (SBO). This suggests that the central nervous system elaborates various references of verticality in function of the task demands and of the available sensory information. In this study, we tested whether the dissociation between SV and SBO appears for a selective stimulation of the vestibular system, by using galvanic vestibular stimulation (GVS).

View Article and Find Full Text PDF

The present study investigated the influence of eye orientation upon the experience of pain. Quasi continuous electrocutaneous stimuli which slowly increased in intensity were delivered to 32 healthy females volunteers. Participants were instructed to direct the eyes at locations that were ipsilateral or contralateral to the stimulated hand.

View Article and Find Full Text PDF

Unlabelled: Human activities often involve sensing body orientation using cues from gravity. Astronauts in microgravity are deprived of those cues and may have difficulty with certain tasks. We theorized that experience in microgravity combined with mechanically induced pressure under the feet (foot pressure) would improve the accuracy of a subject's perception of the body's z-axis as indicated by pointing to the subjective horizon (SH).

View Article and Find Full Text PDF

This study addressed the question of potential disorienting effects associated to head-mounted displays, by investigating the influence of a head-fixed visual frame on the perception of the vertical when the head is tilted in the frontal plane. Subject performance in indicating the vertical was contrasted with the effect of an earth-fixed visual frame as well as with the effect of tilting the head without a frame. With the tilted frames, subjects set the rod in an intermediate direction between the gravitational vertical and the orientation of the frame.

View Article and Find Full Text PDF

Recent studies have shown that the hand-pointing movements within arm's reach remain invariant whether the trunk is recruited or not or its motion is unexpectedly prevented. This suggests the presence of compensatory arm-trunk coordination minimizing the deflections of the hand from the intended trajectory. It has been postulated that vestibular signals elicited by the trunk motion and transmitted to the arm motor system play a major role in the compensation.

View Article and Find Full Text PDF