Evidence review exploring human factors in Advanced Driver Assistance Systems

About the study

This research, commissioned by the UK Department for Transport, reviews evidence on human factors in Advanced Driver Assistance Systems (ADAS), specifically Society Automotive Engineers (SAE) Level 2 systems. These systems can control steering and acceleration/deceleration but require drivers to remain fully engaged and responsible for vehicle operation. By understanding how drivers interact with systems like ADAS, this research will help shape regulations that ensure these technologies are used safely and responsibly, while also considering the evolving role of the human driver in an increasingly automated driving environment. 

Findings

• There was limited understanding among drivers of their responsibilities and capabilities of ADAS, resulting in uncertainty and overestimation of the system's abilities.
• Trust in ADAS varied depending on the technology type, system reliability, and driving conditions. Inappropriate levels of trust led to reduced attention and responsiveness, negatively impacting driver safety. 
• Drivers faced cognitive and behavioural challenges with ADAS, such as lower levels of attention and situational awareness, when using Level 2 systems compared to manual driving.
• Recommendations to address the human factor challenges of ADAS included clearer and more intuitive Human–Machine Interfaces (HMIs), as well as multimodal feedback, such as auditory, visual and haptic cues, to support drivers’ awareness of system activity. Studies also suggested driver monitoring systems that draw on physiological data, including eye, head and body tracking, as well as steering‑wheel sensors that detect whether hands are on the wheel.
• Driver education and training are also identified as potential solutions for the effective and safe use of ADAS.

Methodology

The study used a Rapid Evidence Assessment (REA) approach, involving systematic searches of global academic databases with detailed search strings, focusing on research published from 2017 onwards. From an initial pool of 6,210 papers, 59 studies were selected following a two-stage screening process (title and abstract review).

The included studies examined ADAS technologies capable of controlling steering and speed for extended periods while requiring drivers to remain attentive, with a particular focus on associated human factors. The evidence base comprised simulation studies, real-world driving research, high-quality literature reviews, and surveys.