Driver seat comfort for level 3-4 autonomous vehicles.

Background: Autonomous vehicles can be classified on a scale of automation from 0 to 5, where level 0 corresponds to vehicles that have no automation to level 5 where the vehicle is fully autonomous and it is not possible for the human occupant to take control. At level 2, the driver needs to retain attention as they are in control of at least some systems. Level 3-4 vehicles are capable of full control but the human occupant might be required to, or desire to, intervene in some circumstances.

Improving long term driving comfort by taking breaks - How break activity affects effectiveness.

During long duration journeys, drivers are encouraged to take regular breaks. The benefits of breaks have been documented for safety; breaks may also be beneficial for comfort. The activity undertaken during a break may influence its effectiveness.

An approach to vehicle design: In-depth audit to understand the needs of older drivers.

The population of older people continues to increase around the world, and this trend is expected to continue; the population of older drivers is increasing accordingly. January 2012 figures from the DVLA in the UK stated that there were more than 15 million drivers aged over 60; more than 1 million drivers were aged over 80. There is a need for specific research tools to understand and capture how all users interact with features in the vehicle cabin e.

Effect of long term driving on driver discomfort and its relationship with seat fidgets and movements (SFMs).

Discomfort in vehicle seats is a multifactorial problem with large increases in discomfort occurring during extended duration driving. Due to the nature of driver discomfort, previous research has found it difficult to accurately quantify long term driver discomfort via the use of objective measures. This paper reports a laboratory study that investigates a novel objective measure of long term driver discomfort and its correlation with subjective discomfort ratings.

Driving a better driving experience: a questionnaire survey of older compared with younger drivers.

A questionnaire survey of drivers (n = 903) was conducted covering musculoskeletal symptoms, the vehicle seat, access to specific vehicle features, ingress/egress, driving performance and driving behaviours. Significantly, more discomfort was reported by older drivers (aged 65+) in the hips/thighs/buttocks and knees. Older drivers reported more difficulty parallel parking (p ≤ 0.

Contribution of individual components of a job cycle on overall severity of whole-body vibration exposure: a study in Indian mines.

Drivers of earth-moving machines are exposed to whole-body vibration (WBV). In mining operations there can be a combination of relatively high magnitudes of vibration and long exposure times. Effective risk mitigation requires understanding of the main aspects of a task that pose a hazard to health.

Predicting the health risks related to whole-body vibration and shock: a comparison of alternative assessment methods for high-acceleration events in vehicles.

Unlabelled: In this paper, alternative assessment methods for whole-body vibration and shocks are compared by means of 70 vibration samples measured from 13 work vehicles, deliberately selected to represent periods containing shocks. Five methodologies (ISO 2631-1:1997, BS 6841:1987, ISO 2631-5:2004, DIN SPEC 45697:2012 and one specified by Gunston [2011], 'G-method') were applied to the vibration samples. In order to compare different evaluation metrics, limiting exposures were determined by calculating times to reach the upper limit thresholds given in the methods.

Effects of vertical and side-alternating vibration training on fall risk factors and bone turnover in older people at risk of falls.

Background: whole-body vibration training may improve neuromuscular function, falls risk and bone density, but previous studies have had conflicting findings.

Objective: this study aimed to evaluate the influence of vertical vibration (VV) and side-alternating vibration (SV) on musculoskeletal health in older people at risk of falls.

Design: single-blind, randomised, controlled trial comparing vibration training to sham vibration (Sham) in addition to usual care.

Design of digital filters for frequency weightings (A and C) required for risk assessments of workers exposed to noise.

Many workers are exposed to noise in their industrial environment. Excessive noise exposure can cause health problems and therefore it is important that the worker's noise exposure is assessed. This may require measurement by an equipment manufacturer or the employer.

A survey of expert opinion on the effects of occupational exposures to trunk rotation and whole-body vibration.

We present a review of current expert opinion on the effects of combined exposures to trunk rotation and whole-body vibration (WBV), commonly experienced by operators of agricultural machinery. We evaluate the level of agreement between academic experts in the field of ergonomics, human response to WBV and agricultural operators, on the effects of exposure to WBV and trunk rotation. A total of 83 individuals responded to the paper-based questionnaire, which included questions on risk levels from individual and combined exposures, discomfort development, exposure duration limits and tasks within agriculture.

Subjective ratings of whole-body vibration for single- and multi-axis motion.

Real-world whole-body vibration exposures comprise motion in fore-aft, lateral, and vertical directions simultaneously. There can also be components of roll, pitch, and yaw. If evaluating vibration with respect to human response, most investigators will use methods defined in ISO 2631-1.

Relative contribution of translational and rotational vibration to discomfort.

Understanding how vibration affects discomfort is an important factor for improving work and travelling experience. Methods of evaluating health effects from whole-body vibration are closely linked to those for evaluating discomfort in ISO 2631-1. The standard includes a method to evaluate discomfort using twelve axes of vibration with a similar approach to that for evaluating health effects; thus using all twelve axes gives a possibility to evaluate both health and discomfort.

Effects of horizontal whole-body vibration and standing posture on activity interference.

Standing people are exposed to whole-body vibration in many environments. This paper investigates the effects of horizontal whole-body vibration and standing posture on task performance. Sixteen participants were exposed to random vibration (up to 4 Hz) whilst performing a timed pegboard task in two standing postures.

Earth moving machine whole-body vibration and the contribution of Sub-1Hz components to ISO 2631-1 metrics.

Exposure to whole-body vibration (WBV) is an occupational hazard for operators of industrial vehicles, such as earth-moving machines. Quantification of WBV exposure in terms of impact on health forms one aspect of the Standard ISO 2631-1 (1997). Regarding assessment of risk to health, ISO 2631-1 (1997) states that if WBV components below 1 Hz are not ;relevant nor important' then they can be excluded from the assessment.

Design of digital filters for frequency weightings required for risk assessments of workers exposed to vibration.

Many workers are exposed to vibration in their industrial environment. Vibration can be transmitted through a vehicle seat or a hand-held power tool. Excessive vibration exposure may cause health problems and therefore it is important that the worker's vibration exposure is assessed, which may require measurement by the equipment manufacturer or the employer.

The apparent mass of the seated human exposed to single-axis and multi-axis whole-body vibration.

Most workplaces where workers are exposed to whole-body vibration involves simultaneous motion in the fore-and-aft (x-), lateral (y-) and vertical (z-) directions. Previous studies reporting the biomechanical response of people exposed to vibration have almost always used single-axis vibration stimuli. This paper reports a study where apparent masses of 15 subjects were measured whilst exposed to single-axis and tri-axial whole-body vibration.

Influence of carrying heavy loads on soldiers' posture, movements and gait.

Military personnel are required to carry heavy loads whilst marching; this load carriage represents a substantial component of training and combat. Studies in the literature mainly concentrate on physiological effects, with few biomechanical studies of military load carriage systems (LCS). This study examines changes in gait and posture caused by increasing load carriage in military LCS.

Comparison of the apparent mass during exposure to whole-body vertical vibration between Japanese subjects and ISO 5982 standard.

Objective: The purpose of this study was to investigate the apparent mass of the sitting human body and to compare it with current experimental data and the ISO 5982 standard impedance model.

Method: The apparent mass of the seated human body in the vertical direction was measured. Twelve male subjects were exposed to random whole-body vibration of frequency range (1-20 Hz), with a vibration excitation level of 1.

Effect of backrest and torso twist on the apparent mass of the seated body exposed to vertical vibration.

Occupational exposure to whole-body vibration is often combined with a requirement to perform twisting actions. This paper reports a study where the effect of twisting on the biomechanical response of the seated person was investigated. Twelve male subjects were exposed to vertical random whole-body vibration at 0.

Impedance methods (apparent mass, driving point mechanical impedance and absorbed power) for assessment of the biomechanical response of the seated person to whole-body vibration.

Exposure to whole-body vibration is a risk factor for the development of low back pain. In order to develop a fuller understanding of the response of the seated person to vibration, experiments have been conducted in the laboratory investigating the biomechanics of the seated person. Some of these methods are based on the driving force and acceleration at the seat and are reported in the literature as apparent mass, driving point mechanical impedance or absorbed power.

Equal sensation curves for whole-body vibration expressed as a function of driving force.

Previous studies have shown that the seated human is most sensitive to whole-body vertical vibration at about 5 Hz. Similarly, the body shows an apparent mass resonance at about 5 Hz. Considering these similarities between the biomechanical and subjective responses, it was hypothesized that, at low frequencies, subjective ratings of whole-body vibration might be directly proportional to the driving force.

Comparison of the apparent mass of the seated human measured using random and sinusoidal vibration.

Exposure to whole-body vibration is generally accepted as being a risk factor for low back pain and therefore exposure to vibration should be minimised. The results of previous laboratory based research investigating the biomechanical response of the seated human to vibration has been used to develop models that can be used within tools that are capable of predicting the response of seats. Several studies in the literature have reported apparent masses of seated human subjects whilst exposed to either random or sinusoidal vibration.