Partial driving automation creates a tension: drivers remain legally responsible for vehicle behaviour, yet their active control is significantly reduced. This reduction undermines the engagement and sense of agency needed to intervene safely. Meaningful human control (MHC) has been proposed as a normative framework to address this tension. However, empirical methods for evaluating whether existing systems actually provide MHC remain underdeveloped. In this study, we investigated the extent to which drivers experience MHC when interacting with partially automated driving systems. Twenty-four drivers completed a simulator study involving silent automation failures under two modes - haptic shared control (HSC) and traded control (TC). We derived behavioural metrics from telemetry data, subjective perception scores from post-trial surveys and used them to test hypothesised relations between them derived from the properties of systems under MHC. The confirmatory analysis showed a significant negative correlation between the perception of the automated vehicle (AV) understanding the driver and conflict in steering torques. An exploratory analysis also revealed a surprising positive correlation between reaction times and the perception of sufficient control. Qualitative feedback from open-ended post-experiment questionnaires revealed that mismatches in intentions between the driver and automation, lack of safety, and resistance to driver inputs contribute to the reduction of perceived MHC, while subtle haptic guidance aligned with driver intent had a positive effect. These findings suggest that future designs should prioritise effortless driver interventions, transparent communication of automation intent, and context-sensitive authority allocation to strengthen meaningful human control in partially automated driving.

翻译：部分驾驶自动化引发了一个矛盾：驾驶员在法律上仍需对车辆的行为负责，但其主动控制能力却显著降低。这种降低削弱了安全干预所需的参与感和能动性。有意义的人类控制（MHC）已被提出作为解决这一矛盾的规范性框架，但评估现有系统是否真正提供MHC的实证方法仍不成熟。本研究探讨了驾驶员在与部分自动驾驶系统交互时体验MHC的程度。24名驾驶员完成了一项模拟器研究，涉及两种模式（触觉共享控制（HSC）和交易控制（TC））下的静默自动化失效。我们从遥测数据中提取了行为指标，通过试验后调查获得主观感知评分，并利用这些数据检验了基于MHC系统属性推导出的假设关系。验证性分析显示，驾驶员对自动驾驶车辆（AV）理解自身的感知与转向扭矩冲突之间存在显著负相关。探索性分析还揭示了一个令人意外的发现：反应时间与对充足控制的感知呈正相关。开放式实验后问卷的定性反馈表明，驾驶员与自动化之间意图不匹配、安全性缺失以及对驾驶员输入的抗拒会降低感知到的MHC，而符合驾驶员意图的细微触觉引导则产生了积极影响。这些发现表明，未来设计应优先考虑将驾驶员干预轻松化、自动化意图透明化以及情境敏感的权限分配，以加强部分自动驾驶中人类的有意义控制。