Vehicle Safety and Older Occupants

Toward best practice in Human Machine Interface design for older drivers: A review of current design guidelines

Older adults are the fastest growing segment of the driving population. While there is a strong emphasis for older people to maintain their mobility, the safety of older drivers is a serious community concern. Frailty and declines in a range of age-related sensory, cognitive, and physical impairments can place older drivers at an increased risk of crash-related injuries and death. A number of studies have indicated that in-vehicle technologies such as Advanced Driver Assistance Systems (ADAS) and In-Vehicle Information Systems (IVIS) may provide assistance to older drivers. However, these technologies will only benefit older drivers if their design is congruent with the complex needs and diverse abilities of this driving cohort. The design of ADAS and IVIS is largely informed by automotive Human Machine Interface (HMI) guidelines. However, it is unclear to what extent the declining sensory, cognitive and physical capabilities of older drivers are addressed in the current guidelines. This paper provides a review of key current design guidelines for IVIS and ADAS with respect to the extent they address age-related changes in functional capacities. The review revealed that most of the HMI guidelines do not address design issues related to older driver impairments. In fact, in many guidelines driver age and sensory cognitive and physical impairments are not mentioned at all and where reference is made, it is typically very broad. Prescriptive advice on how to actually design a system so that it addresses the needs and limitations of older drivers is not provided. In order for older drivers to reap the full benefits that in-vehicle technology can afford, it is critical that further work establish how older driver limitations and capabilities can be supported by the system design process, including their inclusion into HMI design guidelines.

Using Simulation to Better Understand the Effects of Aging on Driver Visibility

This proof-of-concept pilot study explored virtual simulation methodology to quantify blind-spot line-of-sight using avatars derived from an older driver database (n = 100). Siemens Jack software simulated the blind spots of eight older driver avatars (four female). The male and female avatars were scaled to be small (25th percentile) and large (75th percentile) based on the height distribution for the older driver database, and had either "normal" (65 degrees) or "abnormal" (50 degrees) neck range of motion (ROM). A virtual model of a Volkswagen Beetle was used to illustrate left and right blind-spot line-of-sight for each avatar. Average line-of-sight between blind spots was 22.3 per cent and 10.4 per cent in the "normal" and "abnormal" rotational neck ROM conditions, respectively. Older drivers with functional impairments affecting neck ROM are more likely to have problems with left blind-spot line-of-sight. Findings are discussed with regard to vehicle design considerations for older adults.

It cannot be all about safety: the benefits of prolonged mobility

OBJECTIVES

While there is much emphasis on managing the safety of older road users, there is limited understanding and recognition of the significance of mobility and transportation needs, mobility changes in later life, and the impact of reduced mobility on quality of life. Moreover, there is little information about the measures that can be taken to increase or at least maintain mobility in older age.

METHOD

A systematic literature review was undertaken to address the issues associated with the transportation and mobility needs of older road users. Articles and publications were selected for relevance and research strength and strategies and measures aimed to manage the safe mobility of older road users were reviewed.

RESULTS AND DISCUSSION

The review provides clear evidence that, for older adults who cease driving, quality of life is reduced and that there are a number of adverse consequences of poor mobility. The misconceptions regarding the risks that older drivers pose on the road and how their safe mobility should be managed are discussed, particularly the implications of current licensing procedures on mobility. Evidence is also presented showing there are subgroups of older adults who are more likely to suffer more pronounced mobility consequences including women and financially disadvantaged groups. Moreover, "best-practice" strategies for maintaining at least some level of mobility for older adults are highlighted in four broad categories: safer road users, safer vehicles, safer roads and infrastructure, and provision of new and innovative alternative transport options that are specifically tailored to older adults.

CONCLUSIONS

Provision of safe travel options that allow easy access to services and amenities is a vital factor in maintaining mobility amongst older road users. An understanding that continued mobility means access to a private vehicle, either as a driver (for as long as possible as it is safe to drive) or as a passenger, and easy and practical access to other forms of transport is essential in the management of health, well-being, and the safe mobility of older road users.