Side Mirror Research Articles

Investigating lane change behaviors and difficulties for senior drivers using naturalistic driving data

Introduction: Lane changes can be a complicated maneuver occurring a dynamic environment requiring the integration of many streams of information. Older drivers may struggle with lane changes which may elevate crash risk. Methods: Real-world lane change behaviors were examined using the Second Strategic Highway Research Program Naturalistic Driving Study database. A total of 393 lane changes were observed for two age groups: middle-aged (30–49), and older (70+) drivers. Results: Older drivers were highly likely to fail to execute an over-the-shoulder glance prior to initiation of a lane change (in 98% of left lane changes and 92% for right lane changes). Older drivers also showed higher rates of OTS glance errors at any point during the lane change in 95% of left lane changes and 86% of right-lane changes. Additionally, older drivers frequently failed to activate the turn signal prior to lane change initiation (60% of lane changes for right changes and 59% for left lane changes). Of the older drivers that made side mirror glances, many occurred after the initiation of the maneuver (46% of left lane changes and 58% of right lane changes) suggesting glances were occurring while changing lanes. Conclusions: Results for older drivers showed that many key glances (particularly side mirror checks) and turn signal actuations observed in the current study occurred after the initiation of the lane change, ostensibly when this action may be too late to gather relevant information and avoid a conflict. Practical Applications: Knowledge of glance patterns during lane changes for older drivers can help older drivers maintain travel mobility as they age. Either through training to reinforce OTS and side mirror glances, or supplemental devices like convex mirrors or oversized rearview mirrors, older drivers can reduce high-risk lane change maneuvers and help older drivers to maintain their mobility and independence longer.

Signal Sensing on Heavy Goods Vehicle (Hgv) Blind Spot Area for Construction Logistics

This paper will explore the issues and the causes of accidents contributed by heavy goods vehicles (HGV) specifically instigated by blind spot. A blind spot is an area or zone that cannot be directly observe by the truck driver on their side mirror. Unfortunately, due to this, high number of accidents had happened because of HGV drivers were not alert or aware of another road user or pedestrian hidden in the blind spot area. This often occurred to heavy goods vehicle drivers. The aim of this paper is to understand the issue of HGV blind spot and identify the potential use signal sensing as an alert mechanism for the blind spot of a heavy goods vehicles. This is to detect other road users who are in the dangerous distance of the HGV. This study has revealed the holistic understanding of HGV blind spot issues and problem by finding the answer for research question initially outlined.

Lane-changing-decision characteristics and the allocation of visual attention of drivers with an angry driving style

The aim of this study was to examine the interactions between the road situational risk and angry driving style on lane-changing decisions in drivers and the allocation of visual attention of angry-driving-style drivers based on video clips of driving. We employed the Tobii eye tracker to collect the eye movement markers and reaction time data of 35 drivers. First, the road type and distances of neighboring cars were used to classify situations in the video clips into high- and low-risk situations. The revised Chinese version of the Multidimensional Driving Style Inventory (MDSI-C) was used to measure the driving style of drivers. The eye movement heatmap of drivers was used to classify the areas of interest into the front view and side mirror. We found that the angry driving style and the total fixation duration on the front view of drivers in high-risk situations were predictors of the relative lane-changing decision time. Angry-driving-style drivers’ relative lane-changing decision time is shorter than that of other drivers. In high-risk driving situations, the longer the total fixation duration on the front view, the shorter the relative lane-changing decision time. We also found that the angry driving style and eye movement areas of interest interacted with the mean search durations and total fixation durations of the drivers. Angry-driving-style drivers were more focused on the front view. Our study has significance for the improvement of the improvement of the allocation of visual attention of angry-driving-style drivers and the development of advanced driver assistance systems (ADAS) and connected and autonomous vehicles (CAVs).

Advances in Experimental Vehicle Soiling Tests

<div class="section abstract"><div class="htmlview paragraph">The field of vision of the driver during wet road conditions is essential for safety at all times. Additionally, the safe use of the increasing number of sensors integrated in modern cars for autonomous driving and intelligent driver assistant systems has to be ensured even under challenging weather conditions. To fulfil these requirements during the development process of new cars, experimental and numerical investigations of vehicle soiling are performed. This paper presents the surface contamination of self- and foreign-soiling tested in the wind tunnel. For these type of tests, the fluorescence method is state-of-the-art and widely used for visualizing critical areas. In the last years, the importance of parameters like the contact angle have been identified when designing the experimental setup. In addition, new visualization techniques have been introduced. Based on these developments the complete process using the fluorescence method was evaluated and updated to the available technology. Various factors in the experimental setup were identified to improve the reliability and a resulting high repeatability of the experiments between different test sessions is shown. Additionally, new visualization techniques are introduced for enhanced data evaluation which allows an easier identification of possible measures. Due to the increased repeatability, it is now possible to calculate the absolute difference between two analyzed vehicle configurations. For the side mirror glass, the quality of the results is improved by image detection methods. In the end it is shown that these modifications to the process are helpful in evaluating the results of computational fluid dynamics.</div></div>

Tailored disorder: a self-organized photonic contact for light trapping in silicon-based tandem solar cells.

We present a process development leading to efficient rear side light trapping structures with the purpose of enhancing the infrared response of a silicon-based tandem solar cell. To this end, we make use of phase separation effects of two immiscible polymers, polystyrene and poly(methyl methacrylate), resulting in a non-periodic polystyrene structure on silicon with a well-defined size distribution. Onto this pattern, we evaporate silver as a scattering rear side mirror and contact layer. Average feature sizes and periods can be tuned by varying material properties (e.g. molar weights or ratios of the polymers) as well as processing conditions during the spin coating. This way a favorable pseudo period of approx. 1 µm for these disordered structure features was realized and successfully implemented into a silicon solar cell. The structure shows a ring-shaped scattering distribution which is beneficial for light trapping in solar cells. External quantum efficiency measurements show that a gain in short circuit current density of 1.1 mA/cm2 compared to a planar reference can be achieved, which is in the same range as we achieved using nanoimprint lithography in a record triple-junction III/V on a silicon device.

Experimental analysis of hydrodynamic and acoustic pressure on automotive front side window

Both the hydrodynamic and acoustic pressure on automotive front side window have the potential contribution to the interior sound pressure of the vehicle. The corrected force analysis technique (CFAT) is employed to extract the acoustic pressure on front side window. The sensitivity of all pressure fluctuation inside and outside the vehicle to the variation of wind speed, yaw angle and the geometry of side mirror is analyzed. The scaling law of both hydrodynamic and acoustic pressure is derived, compared and used to confirm the validation of CFAT. The coherence function and contribution coefficient are used to analyze the relative contribution of hydrodynamic and acoustic pressure on front side window to the interior sound pressure. Results show that in the middle and high frequency range, although the magnitude of acoustic pressure on front side window is much smaller than that of hydrodynamic pressure, the acoustic pressure on front side window contributes much more than the hydrodynamic pressure into the interior sound pressure.

Study on Radiated Noise of a Panel under Fluctuating Surface Pressure Due to an Idealized Side Mirror

As traditional automobiles develop towards new energy vehicles, the noise, vibration and harshness (NVH) performance of automobiles is facing new challenges. Without the cover of the traditional engine noise and inlet and exhaust noise, the high-speed wind noise becomes more prominent. Thus, research on the calculation method of vehicle interior noise in high-speed driving condition is needed. However, vehicle body structure is complex, and the external excitation components are complicated. In order to analyze the method of predicting the vehicle interior noise at high speed, an idealized side mirror model is taken as the research object in this paper and the radiated noise of a panel under the fluctuating surface pressure (FSP) due to the idealized side mirror is studied. The FSP of the panel is first studied by the numerical simulations of incompressible and compressible flow field. For the incompressible flow field, the Corcos turbulent boundary layer (TBL) model is established to simulate the convective component and the boundary element method (BEM) is used to extract the acoustic component. Subsequently, the Corcos model coupling BEM method, the random modal force coupling BEM method and the deterministic modal force coupling BEM method are used separately to calculate the noise of the panel under the FSP. For the compressible flow field, the convective and acoustic component in the fluctuating pressure are separated by the wavenumber-frequency spectrum (WFS) method. The radiated noise of the panel under the FSP is calculated again by using the WFS, the method of random modal force and the method of deterministic modal force, respectively. Then, the computational time of the six methods of incompressible and compressible calculation is compared. Finally, a fast and accurate method of calculating the panel radiated noise under FSP is obtained by comparing the computational accuracy with the experimental results and combining the computational time: the method of incompressible random modal force. This method can be used to quickly and accurately analyze the vehicle interior noise at high speed, and to optimize the exterior protrusions and the vehicle sound package for improving the vehicle NVH performance at high speed.

Factors affecting lane change crashes

This study aims to investigate the contributing factors affecting the occurrence of crashes while lane-changing maneuvers of drivers. Two different data sets were used from the same drivers' population. The first data set was collected from the traffic police crash reports and the second data set was collected through a questionnaire survey that was conducted among 429 drivers. Two different logistic regression models were developed by employing the two sets of the collected data. The results of the crash occurrence model showed that the drivers' factors (gender, nationality and years of experience in driving), location and surrounding condition factors (non-junction locations, light and road surface conditions) and roads feature (road type, number of lanes and speed limit value) are the significant variables that affected the occurrence of lane-change crashes. About 57.2% of the survey responders committed that different sources of distractions were the main reason for their sudden or unsafe lane change including 21.2% was due to mobile usage. The drivers' behavior model results showed that drivers who did sudden lane change are more likely to be involved in traffic crashes with 2.53 times than others. The drivers who look towards the side mirrors and who look out the windows before lane-change intention have less probability to be involved in crashes by 4.61 and 3.85 times than others, respectively. Another interesting finding is that drivers who reported that they received enough training about safe lane change maneuvering during issuing the driving licenses are less likely to be involved in crashes by 2.06 times than other drivers.

Does a Circular Convex Blind Spot Mirror Increase the Driver’s Field of View?


 
 
 Many road traffic accidents occur in Malaysia every year. Road fatalities has been one of the main causes of death in Malaysia. More than half of these fatalities were among motorcyclists. An accident between a passenger car and a motorcycle might be caused by the blind spot of the car driver, in which the driver was unable to notice an incoming motorcycle from behind or the side. Blind spot monitoring system has been developed using recent technology. However, this active blind spot monitoring system is expensive and only available in luxury cars. Another type of blind spot monitoring is known as passive blind spot monitoring by means of a convex mirror. Many convex blind mirrors are being sold nationwide that come in various shapes. Nonetheless, the effectiveness of this convex mirror has never been quantified. This study aims to experimentally quantify the effectiveness of this mirror by using a spotlight, projecting a direct light to the side mirror. A circular convex mirror was placed at four different locations, one at a time. It is hypothesised that the reflection of the light on a flat, white wall indicates the driver’s field of view. The area of the reflection was calculated using image processing, and the values of all five cases were compared. It was found that the circular convex mirror increases the field of view by up to 211 %. The position of the convex mirror plays an important role to ensure a maximum field of view is achieved. This paper has demonstrated that the usage of a circular convex mirror does increase the driver's field of view.
 
 

Preferred E-mirror luminance levels for diverse ambient light conditions

E-mirrors comprised of cameras and visual displays are expected to replace current side mirrors. Although previous studies have extensively examined the effects of E-mirror size and location on dri...

AI Enabled Blind Spot Detection using Rcnn Based Image Processing

Due to the rapid increase in the rate of road accidents and traffic density, modern automobiles are equipped with intelligent systems like Adaptive cruise control and Lane Departure Warning System. Therear-view mirror can be effective to observe a limited range only and there are zones that cannot be viewed. This region is referred to as the blind spot. Therefore, we present a method to detect the vehicles from the side and the rear for Blind Spot Detection with vision system incorporating RCNN. Blind spot detection is a key technology among driver aids that provides 360 degrees of electronic coverage around the car during motion.The methodology presented in this paper uses two stereo cameras as input devices which constantly capture the images at the blind spot area and the information is passed to the main controlling unit. Potholes are also detected and the alert is sent to the nearby vehicle. The incorporation of Artificial Intelligence would help in enhancing the picture quality and blur or cancel the background images probable of misreading the target image. RCNN is used for the vehicle detection and for evaluating the relative distance between the vehicles.This technology allows us to provide a realistic environment for commercial vehicle drivers as they can’t monitor the side and rear-view mirrors all the time, making the whole driving experience more comfortable

Task Interruption and Control Recovery Strategies After Take-Over Requests Emphasize Need for Measures of Situation Awareness.

Our objective was to determine whether there is a need to go beyond measures of automation deactivation time to understand the transition to manual driving after take-over requests (TORs) using the example of office tasks as nondriving-related tasks (NDRTs). Office tasks are likely NDRTs during automated commutes to/from work. Complex tasks can influence how manual control and visual attention is recovered after TORs. N = 51 participants in a driving simulator performed either one of two office tasks or no task (between subjects). We recorded reaction times in a high-urgency and low-urgency scenario (within subjects) and analyzed task interruption strategies. 90% of the participants who performed an NDRT deactivated the automation after 7 to 8 s. However, 90% of the same drivers looked at the side mirror for the first time only after 11 to 14 s. Drivers with office tasks either interrupted the tasks sequentially or in parallel. Strategies were not adapted to the take-over situation or the task but appeared to be due to individual preferences. Drivers engaged in NDRTs may neglect lower priority subtasks after a TOR, such as mirror checking. Therefore, there is a need to go beyond measures of automation deactivation time to understand the transition to manual driving. Using analyses of attentional dynamics during take-over situations may enhance the safety of future car-driver handover assistance systems. If low driver availability is detected, TORs should only be used as a fallback option if sufficient time and adaptive driver support can be provided.

Direct noise computation of a generic vehicle model using a finite volume method

This paper demonstrates the applicability of a finite volume method for the direct noise computation of road vehicles. For this purpose, a generic vehicle model consisting of major aeroacoustic components of a production car is considered. Such components are the A-pillar and the side mirror. The flow past the vehicle model is calculated using a compressible flow solver for low Mach number flows, accompanied with an approach based on detached eddy simulation for turbulence modelling. Two variants of the vehicle model are calculated, namely with and without side mirror. Validation of aerodynamic results is performed by comparing simulated surface pressure spectra on the side window to wind tunnel measurements. Thereafter, acoustic waves generation and propagation are examined. The propagation of acoustic waves from the sources to the windows surface is calculated directly using the compressible solver, as well as indirectly using a surface integral method. The results of both methods are then used as an input for a vibroacoustic model and surface acceleration spectra are compared between both approaches and wind tunnel measurements. A general assessment of both numerical approaches is given and the aeroacoustic impact of the A-pillar as well as the side mirror regarding their contribution to the overall acoustic level is presented.

Head motion coefficient-based algorithm for distracted driving detection

PurposeConcentration is the key to safer driving. Ideally, drivers should focus mainly on front views and side mirrors. Typical distractions are eating, drinking, cell phone use, using and searching things in car as well as looking at something outside the car. In this paper, distracted driving detection algorithm is targeting on nine scenarios nodding, head shaking, moving the head 45° to upper left and back to position, moving the head 45° to lower left and back to position, moving the head 45° to upper right and back to position, moving the head 45° to lower right and back to position, moving the head upward and back to position, head dropping down and blinking as fundamental elements for distracted events. The purpose of this paper is preliminary study these scenarios for the ideal distraction detection, the exact type of distraction.Design/methodology/approachThe system consists of distraction detection module that processes video stream and compute motion coefficient to reinforce identification of distraction conditions of drivers. Motion coefficient of the video frames is computed which follows by the spike detection via statistical filtering.FindingsThe accuracy of head motion analyzer is given as 98.6 percent. With such satisfactory result, it is concluded that the distraction detection using light computation power algorithm is an appropriate direction and further work could be devoted on more scenarios as well as background light intensity and resolution of video frames.Originality/valueThe system aimed at detecting the distraction of the public transport driver. By providing instant response and timely warning, it can lower the road traffic accidents and casualties due to poor physical conditions. A low latency and lightweight head motion detector has been developed for online driver awareness monitoring.

Turbulent Pressure Spectra for Separated Flow Conditions

<div class="section abstract"><div class="htmlview paragraph">The magnitude of the turbulent pressure spectrum in fluid flow over an obstruction is usually much larger than in attached flow over a smooth surface. External features on a vehicle, such as windshield wipers, side mirrors and pillars which cause flow separation, are a major source of wind noise. The modeling of the pressure spectrum in separated flow is important for designing quiet vehicles. In this study wind tunnel tests have been performed with different shaped obstructions to measure and correlate the surface pressure spectra with flow parameters such as the pressure coefficient and separation size. The model by Chase for attached turbulent boundary layer pressures is generalized to apply to separated flow conditions.</div></div>

The unsteady continuous adjoint method for minimizing flow-induced sound radiation

This paper develops the unsteady continuous adjoint method for aeroacoustic optimization problems governed by time-dependent turbulent flows. To predict the flow-induced sound radiation from a body in free-stream, an incompressible Improved Delayed Detached Eddy Simulation is firstly performed. The generated noise is then propagated with the Kirchhoff Integral method, which uses the pressure distribution on the body surface to compute the sound pressure at selected receivers. The continuous adjoint method for the aforementioned process is developed and presented for the first time. The differentiated Kirchhoff Integral is used to compute the boundary condition of the adjoint velocity on the body surface and, then, the unsteady adjoint equations are solved backwards in time. The time window during which the simulation is performed and the one during which the objective function is evaluated do not coincide. This is reflected on the adjoint boundary conditions along the body and the time integration of the sensitivity derivatives. To ensure the consistency of the continuous adjoint-based gradients, grid sensitivities are taken into account. By incorporating the grid displacement equations during the mathematical development of the adjoint method, the surface integral of the residuals of the flow PDEs, which is commonly omitted, is replaced with a volume integral of the grid sensitivities and gives rise to the adjoint grid displacement equations along with an accurate sensitivity derivatives expression. The proposed method is verified against finite differences in a 3D turbulent flow around a cylinder and, then, applied to a real-world test case, concerned with the flow-induced sound radiation of the side mirror of the generic SAE vehicle.

Investigating driver gaze behavior during lane changes using two visual cues: ambient light and focal icons

Currently, lane change decision aid systems primarily address foveal vision and thus compete for drivers’ attention with interfaces of other assistant systems. Also, alternative modalities such as acoustic perception (Mahapatra et al., in: 2008 International conference on advanced computer theory and engineering, pp 992–995. https://doi.org/10.1109/ICACTE.2008.165 , 2008), tactile perception (Locken et al., in: Adjunct proceedings of the 7th international conference on automotive user interfaces and interactive vehicular applications, AutomotiveUI ’15, pp 32–37. ACM, New York, NY, USA. https://doi.org/10.1145/2809730.2809758 , 2015), or peripheral vision (Locken et al., in: Proceedings of the 7th international conference on automotive user interfaces and interactive vehicular applications, AutomotiveUI ’15, pp 204–211. ACM, New York, NY, USA. https://doi.org/10.1145/2799250.2799259 , 2015), have been introduced for lane change support. We are especially interested in ambient light displays (ALD) addressing peripheral vision since they can adapt to the driver’s attention using changing saliency levels (Matthews et al., in: Proceedings of the 17th Annual ACM symposium on user interface software and technology, UIST ’04, pp 247–256, ACM. https://doi.org/10.1145/1029632.1029676 , 2004). The primary objective of this research is to compare the effect of ambient light and focal icons on driving performance and gaze behavior. We conducted two driving simulator experiments. The first experiment evaluated an ambient light cue in a free driving scenario. The second one focused on the difference in gaze behavior between ALD and focal icons, called “abstract faces with emotional expressions” (FEE). The results show that drivers decide more often for safe gaps in rightward maneuvers with ambient light cues. Similarly, drivers decide to overtake more often when the gaps are big enough with both displays in the second experiment. Regarding gaze behavior, drivers looked longer towards the forward area, and less often and shorter into the side mirrors when using ALD. This effect supports the assumption that drivers perceive the ALD with peripheral vision. In contrast, FEE did not significantly affect the gaze behavior when compared to driving without assistance. These results help us to understand the effect of different modalities on performance and gaze behavior, and to explore appropriate modalities for lane change support.

Delayed Detached Eddy Simulation of Subcritical Flow past Generic Side Mirror

In the present study, the subcritical flow past a generic side mirror on a base plane is investigated at the Reynolds number of 5.2×105 using delayed detached eddy simulation (DDES) turbulence model. Asides from the capability of capturing main features of the large recirculation vortex in the wake of the side mirror and the front horseshoe vortex, the accuracy of DDES estimation of recirculation length is significantly increased by over 20%, compared to the detached eddy simulation (DES) estimation using the same grid. And DDES prediction of pressure coefficient at the trailing edge of the mirror is in good agreement with the experiments, which is more accurate than both DES and large eddy simulation (LES) results. The results verify the capacity of DDES turbulence model to solve the turbulent flow around the side mirror. This is a key foundation for possible future study of full simulation of external flow field of vehicle.

Large-eddy simulation of turbulent flow over the DrivAer fastback vehicle model

Turbulent flow over the DrivAer fastback vehicle model is investigated using large-eddy simulation with particular emphasis on flow separation, vortical structures and unsteady quantities. A systematic and detailed analysis of the flow field is made considering rotating wheels and moving ground floor. Overall features of vortical structures at the cowl top, behind side mirrors, near front and back wheels, at A-, B- and C-pillars and behind the rear end of the vehicle are revealed by investigating velocity and vorticity fields. The rear end is identified to be the main contributor to the pressure force acting on the vehicle, followed by back and front wheels and side mirrors. The resulting pressure force on the upper part of the vehicle, including A-, B-, and C-pillars but excluding the cowl top and side mirrors, is found to be only slightly higher than the contribution of the gap in the cowl top. Flow separation and resulting vortices do not only have an impact on automotive drag, it is also pointed out how unsteadiness in the flow field affects pressure fluctuations. High levels of surface pressure fluctuations are found near side mirrors and front wheels. Similarities in distributions of pressure fluctuations and turbulent kinetic energy are found.

Prediction of Automobile Aerodynamic Noise around the A-pillar and the Side Mirror by Using Hybrid CAA Method

Prediction of Automobile Aerodynamic Noise around the A-pillar and the Side Mirror by Using Hybrid CAA Method