Taxonomy and Definitions for Terms Related to Driving Automation Systems for On-Road Motor Vehicles

<div class="section abstract"> <div class="htmlview paragraph">This document describes [motor] <i>vehicle driving automation system</i>s that perform part or all of the <i>dynamic driving task</i> (<i>DDT</i>) on a <i>sustained</i> basis. It provides a taxonomy with detailed definitions for six levels of <i>driving automation</i>, ranging from no <i>driving automation</i> (Level 0) to full <i>driving automation</i> (Level 5), in the context of [motor] <i>vehicles</i> (hereafter also referred to as “<i>vehicle</i>” or “<i>vehicles</i>”) and their <i>operation</i> on roadways:</div> <ol class="list nostyle"> <li class="list-item"> <span class="li-label">Level 0:</span> <div class="htmlview paragraph">No Driving Automation</div></li> <li class="list-item"> <span class="li-label">Level 1:</span> <div class="htmlview paragraph">Driver Assistance</div></li> <li class="list-item"> <span class="li-label">Level 2:</span> <div class="htmlview paragraph">Partial Driving Automation</div></li> <li class="list-item"> <span class="li-label">Level 3:</span> <div class="htmlview paragraph">Conditional Driving Automation</div></li> <li class="list-item"> <span class="li-label">Level 4:</span> <div class="htmlview paragraph">High Driving Automation</div></li> <li class="list-item"> <span class="li-label">Level 5:</span> <div class="htmlview paragraph">Full Driving Automation</div></li></ol> <div class="htmlview paragraph">These level definitions, along with additional supporting terms and definitions provided herein, can be used to describe the full range of <i>driving automation features</i> equipped on [motor] <i>vehicles</i> in a functionally consistent and coherent manner. “On-road” refers to publicly accessible roadways (including parking areas and private campuses that permit public access) that collectively serve all road <i>users</i>, including cyclists, pedestrians, and <i>users</i> of <i>vehicles</i> with and without <i>driving automation features</i>.</div> <div class="htmlview paragraph">The levels apply to the <i>driving automation feature</i>(s) that are engaged in any given instance of on-road <i>operation</i> of an equipped <i>vehicle</i>. As such, although a given <i>vehicle</i> may be equipped with a <i>driving automation system</i> that is capable of delivering multiple <i>driving automation features</i> that perform at different levels, the level of <i>driving automation</i> exhibited in any given instance is determined by the <i>feature</i>(s) that are engaged.</div> <div class="htmlview paragraph">This document also refers to three primary actors in driving: the (human) <i>user</i>, the <i>driving automation system</i>, and other <i>vehicle</i> systems and components. These other <i>vehicle</i> systems and components (or the <i>vehicle</i> in general terms) do not include the <i>driving automation system</i> in this model, even though as a practical matter a <i>driving automation system</i> may actually share hardware and software components with other <i>vehicle</i> systems, such as a processing module(s) or <i>operating</i> code.</div> <div class="htmlview paragraph">The levels of <i>driving automation</i> are defined by reference to the specific role played by each of the three primary actors in performance of the <i>DDT</i> and/or <i>DDT fallback</i>. “Role” in this context refers to the expected role of a given primary actor, based on the design of the <i>driving automation system</i> in question and not necessarily to the actual performance of a given primary actor. For example, a <i>driver</i> who fails to monitor the roadway during engagement of a Level 1 adaptive cruise control (ACC) system still has the role of <i>driver</i>, even while s/he is neglecting it.</div> <div class="htmlview paragraph"><i>Active safety systems</i>, such as electronic stability control (ESC) and automatic emergency braking (AEB), and certain types of <i>driver</i> assistance systems, such as lane keeping assistance (LKA), are excluded from the scope of this <i>driving automation</i> taxonomy because they do not perform part or all of the <i>DDT</i> on a <i>sustained</i> basis, but rather provide momentary intervention during potentially hazardous situations. Due to the momentary nature of the actions of <i>active safety systems</i>, their intervention does not change or eliminate the role of the <i>driver</i> in performing part or all of the <i>DDT</i>, and thus are not considered to be <i>driving automation</i>, even though they perform automated functions. In addition, systems that inform, alert, or warn the <i>driver</i> about hazards in the driving environment are also outside the scope of this <i>driving automation</i> taxonomy, as they neither automate part or all of the <i>DDT</i>, nor change the <i>driver</i>’s role in performance of the <i>DDT</i> (see <span class="xref">8.13</span>).</div> <div class="htmlview paragraph">It should be noted, however, that crash avoidance <i>features</i>, including intervention-type <i>active safety systems</i>, may be included in <i>vehicles</i> equipped with <i>driving automation system</i>s at any level. For <i>automated driving system</i> (<i>ADS</i>) <i>features</i> (i.e., Levels 3 to 5) that perform the complete <i>DDT</i>, crash mitigation and avoidance capability is part of <i>ADS</i> functionality (see also <span class="xref">8.13</span>).</div></div>