Driving Posture Research Articles

Conformal Microwave Sensor for Enhanced Driving Posture Monitoring and Thermal Comfort in Automotive Sector

Conformal Microwave Sensor for Enhanced Driving Posture Monitoring and Thermal Comfort in Automotive Sector

Lower Back & Comfortability Analysis of Driving Posture to Mitigate Musculoskeletal Disorders: An Ergonomics Study using Digital Human Modelling in JACK Software

In this paper, the crucial aspect of driver comfort was explored by investigating the prevailing driving postures among individuals, aiming to discern their ergonomic implications and ascertain whether the commonly adopted postures are conducive to musculoskeletal health or pose potential risks. From the last decade vehicle like cars have become one of the common modes of personal transport. Car has high relevance in day-to-day activities like commuting, economic activities and sports etc. The continuous driving of vehicle can lead the driver prone to musculoskeletal disorders such as back pain, spine injury and posture issues. This study is conducted to address the ergonomic aspects of posture of the driver to highlight the risk of Musculoskeletal disorders (MSDs) and to optimize the driving posture. Lower Back Analysis (LBA) and Comfortability Analysis is performed in JACK Software to analyze the driving posture. A DHM (Digital Human Model) is created in JACK Simulation Software according to the collected anthropometric data of an average Pakistani man. A virtual Environment is created in JACK Simulation Software. The posture of the subject is analyzed by taking measurements of the subject’s angle of joints when they are sitting in a driving posture. For Ergonomic Analysis the Driving Posture is evaluated on JACK software to Mitigate Musculoskeletal Disorders. Results show that the subject is having low back compression force of 672 which is below the NIOSH Back Compression Action Limit of 3400N representing a nominal risk of low back injury.

DNN-Based Prediction of Standard Driving Posture for Vehicle Takeover

DNN-Based Prediction of Standard Driving Posture for Vehicle Takeover

Dynamic Spatial Tuning Patterns of Shoulder Muscles with Volunteers in a Driving Posture.

Computational human body models (HBMs) of drivers for pre-crash simulations need active shoulder muscle control, and volunteer data are lacking. The goal of this paper was to build shoulder muscle dynamic spatial tuning patterns, with a secondary focus to present shoulder kinematic evaluation data. 8M and 9F volunteers sat in a driver posture, with their torso restrained, and were exposed to upper arm dynamic perturbations in eight directions perpendicular to the humerus. A dropping 8-kg weight connected to the elbow through pulleys applied the loads; the exact timing and direction were unknown. Activity in 11 shoulder muscles was measured using surface electrodes, and upper arm kinematics were measured with three cameras. We found directionally specific muscle activity and presented dynamic spatial tuning patterns for each muscle separated by sex. The preferred directions, i.e. the vector mean of a spatial tuning pattern, were similar between males and females, with the largest difference of 31° in the pectoralis major muscle. Males and females had similar elbow displacements. The maxima of elbow displacements in the loading plane for males was 189 ± 36 mm during flexion loading, and for females, it was 196 ± 36 mm during adduction loading. The data presented here can be used to design shoulder muscle controllers for HBMs and evaluate the performance of shoulder models.

MUSCLE CONTRACTION DURING MANEUVERING STEERING WHEEL USING SURFACE ELECTROMYOGRAPYHY

Driving posture is one of the factors that need to be emphasized in ensuring driver’s comfort and to avoid road accidents and injuries. Meanwhile, fatigue has a strong relationship with comfortable posture and it contributes 15.7% of the total road accidents in Malaysia. Fatigue can reduce driving concentration and performances, thus increases the risk of road accidents and injuries. In order to determine the driver’s comfort, this study had measured muscle contraction using the objective measurement for comfortable and optimum driving posture angles. The equipment used for conducting objective measurement on 14 respondents was sEMG. The researcher had used sEMG equipment to evaluate muscles activities at upper extremities, which comprises of Biceps Brachii (BB), Deltoid Anterior (DA) and Trapezious Upper (TU) that were involved during controlling the car steering. It involves three driving postures parameters according to the fixed elbow and shoulder angles. The results from this study showed the BB muscle increased positively when turning the steering wheel to the right within 3 to 6 times value increased. Meanwhile, DA and TU muscles experience a contraction in the opposite direction with steering wheel turning action, which shows higher right side DA and TU muscle contraction when the driver turn the steering to the left with around 80% decrease for DA and within 60% to 80% decrease value for TU. BB muscle also shows an increasing value of muscle contraction with higher elbow flexion, meanwhile DA and TU muscles contraction also show an increment in-line with greater shoulder abduction. The results showed that posture B with elbow angle at 36° and shoulder angle at 134° are the most comfortable driving postures, hence the lowest muscle contraction value of 15.67μV (BB), 19.31μV (DA) and 12.36μV (TU) compared to the other two measured postures. The results of muscle contraction from this study is capable of assisting researchers and car manufacturers to understand the relationship of steering maneuvering when developing more comfortable and suitable vehicle’s driver seat compartment.

Pattern of Pressure Distribution on the Car Seat Under Static Condition and Its Relationship with Driving Posture

Assessment of sitting condition on the car seat is important as the driver requires to remain seated while maneuvering the car. The seating situation with relatively restricted position and posture can lead to discomfort and fatigue among drivers. When the driver is getting fatigue, it may reduce the performance, and hence increase the risk of road accident. Up to this date, numerous study were conducted to solve this issue. However, majority of these studies performed the study in the laboratory. Furthermore, majority of the experiment were not used the actual car and provide clear interaction between driving posture and pressure distribution pattern. Hence, this study aims to determine the onset level of driver’s condition in term of discomfort rating scale and pressure distribution on the car seat under static condition by using actual car. Forty-four participants involved in this study by integrating discomfort rating assessment for the subjective evaluation and Pressure Sensor for the objective assessment. There were two main sections for subjective assessment that required the participant to provide the feedback on general discomfort level and body part discomfort while seating. Meanwhile, objective assessment used pressure map by Tactilus with 32 x 32 sensor matrix. All participants were required to sit on the car seat for five minutes. Findings showed that the driver’s discomfort and pressure pattern increased with time. In addition, the peak pressure distribution was found at the right buttock of the participant. Driving posture also influence the pattern of pressure distribution. This study provides a guideline for the automotive manufacturer to provide the optimal design of the car seat by maximizing the seat materials in term of quantity and quality with the highest pressure distribution levels. This adjustment can help to minimize the load concentration by providing a good pressure distribution.

Amplitude Analysis of Lower Leg Muscle in Car Pedal Operation in Specific Driving Posture and Duration

Driving posture is important to determine the comfortability of the driver. The purpose of this study is to investigate the muscle response in car pedal operation. To evaluate this response, 11 volunteers involved in simulated driving experiment using an electrical impedance myography to detect the muscle contraction of the lower leg, particularly at Gastrocnemius medial (GM). The driver requires to perform different pedal actions. The results depict that GM muscle shows different reaction according to pedal actions. According to these results, different degree of ankle angle lead to different muscle response. These findings help us to understand the effect of physical attribute related to muscle response and joint angle on driver during monotonous driving task.

Statistical Models for Predicting Automobile Driving Postures for Men and Women Including Effects of Age.

Previously published statistical models of driving posture have been effective for vehicle design but have not taken into account the effects of age. The present study developed new statistical models for predicting driving posture. Driving postures of 90 U.S. drivers with a wide range of age and body size were measured in laboratory mockup in nine package conditions. Posture-prediction models for female and male drivers were separately developed by employing a stepwise regression technique using age, body dimensions, vehicle package conditions, and two-way interactions, among other variables. Driving posture was significantly associated with age, and the effects of other variables depended on age. A set of posture-prediction models is presented for women and men. The results are compared with a previously developed model. The present study is the first study of driver posture to include a large cohort of older drivers and the first to report a significant effect of age. The posture-prediction models can be used to position computational human models or crash-test dummies for vehicle design and assessment.

Long-term Discomfort Evaluation: Comparison of Reported Discomfort between a Concept Elevated Driving Posture and a Conventional Driving Posture

Mounting a seat higher in a vehicle, in comparison to a conventional driving posture, will benefit vehicle design by reducing vehicles’ mass and as a result, possibly reducing emissions over the lifecycle of the vehicle. This paper reports on a study with the objective of comparing reported long-term discomfort between a concept elevated posture seat and a production conventional driving posture seat. A sample of 20 commercial drivers (10 males, 10 females) aged 19-65, were recruited for the study. A concept seat was developed from a seat fitting trial study [1] and a second rig was designed and constructed to replicate a benchmark production seat in a conventional LCV driving posture. In two separate trials, participants were required to perform a driving simulation task whilst exposed to whole-body vibration and report their discomfort in 10minute intervals over 50-minutes of driving. Results indicated that at 50-minutes of driving, there were significant differences in reported discomfort for the right shoulder and the lower back between the postures, with the conventional posture having the higher discomfort ratings. Additionally, the musculoskeletal fatigue effects for both postures (progression of discomfort over time) fell in line with the literature.

A Classification of Sitting Strategies based on Driving Posture Analysis

Objective: The present study is intended to objectively classify upper- & lower-body sitting strategies and identify the effects of gender and OPL type on the sitting strategies.BRBR Background: A sitting strategy which statistically represents comfortable driving posture can be used as a reference posture of a humanoid in virtual design and evaluation of a driver"s seat. Although previous research has classified sitting strategies for driving postures in various occupant package layout (OPL) types, the existing classification methods are not objective and the factors affecting sitting strategies have not been identified.BRBR Method: Forty drivers" preferred driving postures in three different OPL types (coupe, sedan, and SUV) were measured by a motion capture system. Next, the measured driving postures were classified by K-means cluster method. BRBR Results: Sitting strategies of upper-body were classified as erect (33%), slouched (41%), and reclined (26%) postures, and those of lower-body were classified as knee bent (42%), knee extended (32%), and upper-leg lifted (26%) postures. Significant differences at α = 0.05 in the upper-body sitting strategy by gender and lowerbody sitting strategy by OPL type were found.BRBR Application: Both the classified sitting strategies and the identified factors would be of use in ergonomic seat design and evaluation.

Research on Driving Posture Comfort Based on Relation between Drivers' Joint Angles and Joint Torques

Research on Driving Posture Comfort Based on Relation between Drivers' Joint Angles and Joint Torques

Recognizing driving postures by combined features of contourlet transform and edge orientation histogram, and random subspace classifier ensembles

In order to develop Human-centered Driver Assistance Systems (HDAS), an efficient Combined Feature (CF) extraction approach from Contourlet Transform (CT) and Edge Orientation Histogram (EOH) is proposed for vehicle driving posture descriptions. A Random Subspace Ensemble (RSE) of Intersection Kernel Support Vector Machines (IKSVMs) is then exploited as the base classifier. Four testing driving postures are grasping the steering wheel, operating the shift lever, eating a cake, and talking on a cellar phone. On a dedicated Southeast University Driving Posture (SEU-DP) Database, the holdout and cross-validation experiments were conducted. The experimental results show that the proposed CF-RSE approach outperforms single Contourlet-IKSVM, EOH-IKSVM recognition strategies. With CF-RSE, the average classification accuracies of four driving posture classes are over 90%. Among the four classes of driving postures, the class of grasping the steering wheel is the most difficult to recognize and the proposed approach achieved over 85% accuracy in both experiments. These encouraging results show that the proposed CF-RSE approach is effective and hence has great promises in developing a successful HDAS.

Pilot Investigation on the Driving Posture Comfort among Malaysian Drivers

The relationship between preferred driving postures, seat adjustment levels and the anthropometric characteristics of subjects were investigated in this paper. The study is a pilot investigation with the aim to understand comfortable driving postures for Malaysian drivers which will be a basis for further development of a comfort design model in the future. Wireless goniometer and photogrammetry method were used to measure the body’s joint angles. The goniometer was placed on the subject’s shoulders, elbows and knees to measure the shoulder displacement angles, elbow angles and knee angles, while foot-calf angles and trunk-thigh angles were measured using a photogrammetry technique due to the limited number of the goniometers. The seat positions, namely; the seat back angle, seat sliding distance and seat height were measured using a similar photogrammetry method. The subjects’ results show that stature affects their shoulder angles, elbow angles, knee angles, seat height and seat sliding distance. There was a positive correlation between the stature, elbow and seat sliding distance. However, there is no correlation between stature and seat back angles. Based on the results obtained, a taller subject preferred a driving posture that enables their arms to be outstretched; while a female subject preferred to sit closer to the steering wheel and a higher seat for visual demands.

Erratum to: Recognition of driving postures by combined features and random subspace ensemble of multilayer perceptron classifiers

Human-centric driver assistance systems with integrated sensing, processing and networking aim to find solutions for traffic accidents and other relevant issues. The key technology for developing such a system is the capability of automatically understanding and characterizing driver behaviors. This paper proposes a novel driving posture recognition approach, which consists of an efficient combined feature extraction and a random subspace ensemble of multilayer perceptron classifiers. A Southeast University Driving Posture Database (SEU-DP Database) has been created for training and testing the proposed approach. The data set contains driver images of (1) grasping the steering wheel, (2) operating the shift lever, (3) eating a cake and (4) talking on a cellular phone. Combining spatial scale features and histogram-based features, holdout and cross-validation experiments on driving posture classification are conducted, comparatively. The experimental results indicate that the proposed combined feature extraction approach with random subspace ensemble of multilayer perceptron classifiers outperforms the two individual feature extraction approaches. The experiments also suggest that talking on a cellular phone is the most difficult posture in classification among the four predefined postures. Using the proposed approach, the classification accuracy on talking on a cellular phone is over 89 % in both holdout and cross-validation experiments. These results show the effectiveness of the proposed combined feature extraction approach and random subspace ensemble of multilayer perceptron classifiers in automatically understanding and characterizing driver behaviors toward human-centric driver assistance systems.

多面的評価に基づく肉体疲労低減運転姿勢の提案

多面的評価に基づく肉体疲労低減運転姿勢の提案

Predictions of health risks associated with the operation of load-haul-dump mining vehicles: Part 2—Evaluation of operator driving postures and associated postural loading

Driving posture and whole-body vibration (WBV) (reported in Part 1) were measured during the operation of seven load-haul-dump (LHD) mining vehicles. Simultaneous exposure to WBV and non-neutral postures could increase an LHD operator's risk of developing a musculoskeletal injury. The percentage of work time spent in neutral, moderate and severe neck rotation, trunk rotation, trunk flexion and trunk lateral bend postures was determined via a 3DMatch analysis of 1 h of videotaped driving for each LHD operator. Peak and cumulative spinal loads at the L4/L5 level also were estimated using 3DMatch. Operators averaged 89% of the time with their necks rotated more than 40°, 3% of the time with the trunk rotated more than 30°, 24% of the time with the trunk in forward flexion between 20° and 45°, and 16% of the time with the trunk in lateral bend between 15° and 30°. The average maximal compressive force (based on static measure estimations associated with posture only) at the L4/L5 level of the spine was 2176 N, and the cumulative compressive load for an 8-h work shift was 34 MN. A total injury risk score, which considered vibration exposure, working postures and spinal loading, was correlated with LHD operator musculoskeletal injury reports. Therefore, exposure to vibration and non-neutral working postures appears to increase musculoskeletal injury risk amongst LHD operators. Relevance to industry Equipment operators have the potential to be exposed to several factors that can contribute to the onset of adverse health effects. This study illustrates the importance of considering the combined impact of vibration exposure and non-neutral working postures in order to reduce injury risk associated with LHD vehicle operation.

Effects of vehicle interior geometry and anthropometric variables on automobile driving posture.

The effects of vehicle package, seat, and anthropometric variables on posture were studied in a laboratory vehicle mockup. Participants (68 men and women) selected their preferred driving postures in 18 combinations of seat height, fore-aft steering wheel position, and seat cushion angle. Two seats differing in stiffness and seat back contour were used in testing. Driving postures were recorded using a sonic digitizer to measure the 3D locations of body landmarks. All test variables had significant independent effects on driving posture. Drivers were found to adapt to changes in the vehicle geometry primarily by changes in limb posture, whereas torso posture remained relatively constant. Stature accounts for most of the anthropometrically related variability in driving posture, and gender differences appear to be explained by body size variation. Large intersubject differences in torso posture, which are fairly stable across different seat and package conditions, are not closely related to standard anthropometric measures. The findings can be used to predict the effects of changes in vehicle and seat design on driving postures for populations with a wide range of anthropometric characteristics.

Alignment of the Lumbar Vertebrae in a Driving Posture

The purpose of this study was to define the anatomical arrangement of the lumbar spine in the mid-body sagittal plane of a human volunteer while in three postures: a driving posture; full flexion; and full extension. Radiographic images of the lumbar spine were made of a 33-year old 50th percentile male subject seated in a comfortable driving posture. Additional radiographs were made of the lumbar spine while the subject was postured in full voluntary flexion, and full voluntary extension. Anterior and posterior mid-sagittal vertebral endplate positions were plotted on an x-y coordinate system for each posture. Anterior and posterior disk thicknesses, and the positions of the centers of each vertebra were numerically determined using information from the plots. Disk thicknesses were then graphed and comparisons made for each posture. The arrangements of the centers of vertebrae were graphed and compared for the three different postures. The arrangement of the lumbar vertebrae tended toward that of full voluntary flexion while the subject was in a normal driving posture. Anterior disk thickness was a sensitive indicator of posture, while posterior disk thickness was not. While in a driving posture, the lower back approximated a straight-line that was nearly parallel to the seat back axis. The observations support those of an earlier study. Since soft tissue spinal elements can only be damaged by applying tensile forces in excess of their tolerance, the anterior elements of the lumbar spine would not be directly threatened in low velocity frontal collisions, since anterior elements would be in relative compression. Tension injury to the anterior structures as a result of a rear-end collision would first require reversing the preimpact conditions imposed by the normal driving posture. Tension injury to the posterior spinal elements resulting from low velocity rear-end collisions would be unlikely since axial compression loading would also diminish tension stress in posterior soft tissue structures. Any compression injury to posterior elements resulting from rear-end collisions would first require reversing the pre-impact conditions imposed by the normal driving posture.