For adaptive cruise control (ACC) systems to be accepted and used safely, the transitions from cruise control mode to necessary driver intervention need to be obvious to the driver. Previous research shows that drivers have natural boundaries for acceptable values for time headway and time to collision to a car in front, which define at what point they are likely to step on the brake pedal. These boundaries can define an intuitive limit for ACC engagement. However, such boundaries may not be the same for all drivers, and not even for the same driver, whose goals may vary. The present research aimed to measure mental model boundaries in the context of different goals with a motorway cut-in scenario in a driving simulator. Participants drove in three conditions, after being asked to ‘drive safely, ‘drive fuel-efficiently’ and after no specific instructions. The results show that both the safe and eco-driving instructions led drivers to brake at longer safety margins. These findings indicate that, as drivers follow different goals, e.g. as they are reminded to drive safely or eco-friendly, their preferences for operational limits of ACCs may change. This needs to be taken into account for design decisions, e.g. using ‘safe’ and ‘eco’ modes when driving.

中文翻译：

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ACC 安全和燃油效率设计：接受不同驾驶方式时的安全裕度

为了安全地接受和使用自适应巡航控制 (ACC) 系统，从巡航控制模式到必要的驾驶员干预的过渡需要对驾驶员来说是显而易见的。先前的研究表明，驾驶员对可接受的车头时距和与前方车辆发生碰撞的时间有自然的界限，这定义了他们可能踩下制动踏板的时间点。这些边界可以定义 ACC 参与的直观限制。然而，这样的界限对于所有司机来说可能不一样，甚至对于同一个司机来说也不同，他们的目标可能会有所不同。本研究旨在通过驾驶模拟器中的高速公路切入场景在不同目标的背景下测量心理模型边界。参与者在被要求“安全驾驶，“节油驾驶”，没有具体说明。结果表明，安全和环保驾驶指令都使驾驶员在更长的安全裕度下制动。这些发现表明，随着驾驶员遵循不同的目标，例如提醒他们安全或环保地驾驶，他们对 ACC 操作限制的偏好可能会改变。设计决策时需要考虑到这一点，例如在驾驶时使用“安全”和“环保”模式。