Human Drivers and Automated Vehicles team up for the better and the worse: a framework for the analysis of future accidents

Abstract: By and large, the so-called “Human Error” is considered as the main cause of traffic crashes – proportions of “more than 90%” of crashes “caused” by human errors are often mentioned in the press, in the political debate, even in scientific literature. By gradually removing the influence of human factors, the introduction of Automated Vehicles (AV) would then allegedly hugely benefit road safety. However, these analyses leave aside a few hard facts: human factors are often found in combination with other types of factors (e.g. environmental, traffic or vehicular) as generators of road crashes. Indeed, some studies suggest that it is only in about half of the fatal road crashes that human factors are the sole contributors – and can hence be labelled as “sole causers”. Confusions often arise because only the main or the final failure leading to the crash is mentioned by e.g., police forces collecting accident data. Moreover, precise analyses of crash-producing mechanisms highlight human factors relating to failures in the driving functions (e.g., perception failure, lack of anticipation, wrong decision) and human factors explaining these driving failures (e.g., low alertness or attention). AV will remain prone to the former type of failure and will avoid the latter to replace them with entirely new types of failures (e.g., inability to properly identify and classify an obstacle, to assess the intentions of other road users in mixed traffic). All these issues require new analysis models for retrieving the relevant information when collecting accident or safety critical event data and suggesting new road safety measures. Having recently published an entirely new Automated Driver Functional Failures (ADFF) model and an updated taxonomy for Human Functional Failures (HFF) leading to road crashes in the context of shared or delegated driving tasks between human and automated drivers, the authors propose to address, in the present paper, the Explanatory Factors for both types of failures. The analysis of traffic crashes shows that automated drivers didn’t perform as well as human drivers when confronted with conditions impairing their perception system or when driving in a complex environment. Most worrying would be that this complexity could result from failure to identify other road users or obstacles. Finally, although the introduction of AV could suppress some accident-causing human failures, e.g., willful violations of road rules, new features explaining human failures would appear, of which overtrust in AV out of ignorance of the automation’s limits would be an example.

Keywords: Road Safety, Automated Driving, Human Factors

DOI: 10.54941/ahfe1004590

Cite this paper:

​