RATIONALE & INTRODUCTION

Vulnerable Road Users (VRUs) include any person crossing or using a roadway who is not protected by a car. The variety of characteristics and behaviors across the many groups of VRUs can add unique challenges to ADS development. To build public acceptance of ADS technologies, it is critical that developers demonstrate the ADS can safely accommodate these challenges for a given operational design domain (ODD). Establishing a common terminology and a baseline understanding of these challenges is a key first step to building public acceptance. This best practice on VRU interactions can facilitate communication among the industry and public, help calibrate expectations of all traffic participants, ultimately leading to broader acceptance of SAE level 4 and level 5 ADS-equipped vehicles. 

Some of the challenges ADS developers, manufacturers, and fleet operators consider during the design and test for appropriate VRU interactions include their diverse appearances and their behaviors; their kinematics and the presence or absence of appendages. VRUs can be stationary or moving (e.g., police directing traffic or someone riding a kick scooter; may be in or near the roadway effecting traffic (e.g., a road worker or someone changing a tire); or they may be moving with traffic, against it, or across it (e.g., a pedal cyclist, a jogger, or a person using a wheelchair at an intersection). VRUs may be following traffic code (e.g., crossing at a crosswalk) or choosing to violate it (e.g., crossing mid-block). This is not an all-inclusive list of the factors that create interaction challenges for ADS-DVs.

There is currently no consensus on all the factors that should be considered during ADS interaction with VRUs. Broadly speaking, safety performance (in this case, safety during traffic interactions) is improved when all actors (in this case, VRU and ADS) share a general understanding of the world around them. When interacting with VRUs, ADS-DVs need to contribute positively to measures that support overall benefit (refer to AVSC00006202103). In instances where a VRU is following traffic code and behaving in a compliant fashion, this is straightforward; however, most pedestrian fatalities occur at places other than intersections where VRUs failure to follow traffic code can increase the likelihood of a crash. Considering this, ADS developers and manufacturers should account for VRUs that do not follow the traffic code.

SCOPE

This Automated Vehicle Safety Consortium™ (AVSC) best practice provides considerations for ADS developers on interactions between SAE level 4 and level 5 fleet-managed ADS-DVs and VRUs. This document is developed from the perspective of an ADS-DV independent of any external digital communications (i.e., interacting with VRUs that are not connected through some digital communication device such as vehicle-to-pedestrian, vehicle-to-bike, or vehicle-to-infrastructure).