Supplementary data for the paper 'Do sport modes cause behavioral adaptation?'

A key question in transportation research is whether drivers show behavioral adaptation, that is, slower or faster driving, when new technology is introduced into the vehicle. This study investigates behavioral adaptation in response to the sport mode, a technology that alters the vehicle’s auditory, throttle-mapping, power-steering, and chassis settings. Based on the literature, it can be hypothesized that the sport mode increases perceived sportiness and encourages faster driving. Oppositely, the sport mode may increase drivers’ perceived danger, homeostatically causing them to drive more slowly. These hypotheses were tested using an instrumented vehicle on a test track. Thirty-one drivers were asked to drive as they normally would with different sport mode settings: Baseline, Modified Throttle Mapping (MTM), Artificial Engine Sound enhancement (AESe), MTM and AESe combined (MTM-AESe), and MTM, AESe combined with four-wheel steering, increased damping, and decreased power steering (MTM-AESe-4WS). Post-trial questionnaires showed increased perceived sportiness but no differences in perceived danger for the three MTM conditions compared to Baseline. Furthermore, compared to Baseline, MTM led to higher vehicle accelerations and, with a smaller effect size, a higher time-percentage of driving above the 110 km/h speed limit, but not higher cornering speeds. The AESe condition did not significantly affect perceived sportiness, perceived danger, and driving speed compared to Baseline. These findings suggest that behavioral adaptation is a functional and opportunistic phenomenon rather than mediated by perceived sportiness or perceived danger.

交通研究领域的核心议题之一，便是当车辆搭载新技术时，驾驶员是否会产生行为适应性改变——即驾驶速度出现加快或放缓的变化。本研究聚焦于运动模式（sport mode）带来的行为适应性变化：该技术可调整车辆的听觉系统、油门映射、助力转向及底盘参数设置。基于现有文献，可提出两类对立假说：其一，运动模式会提升驾驶员感知到的运动感，进而促使其加快驾驶速度；其二，运动模式可能加剧驾驶员的危险感知，使得其出于内稳态调节而降低驾驶车速。本研究通过配备测试仪器的试验车辆在试验跑道上开展实验，对上述假说进行验证。实验共招募31名驾驶员，要求其以日常驾驶习惯完成五种不同运动模式设置下的驾驶任务：基准模式（Baseline）、改良油门映射（Modified Throttle Mapping，MTM）、人工发动机声音增强（Artificial Engine Sound enhancement，AESe）、MTM与AESe组合模式（MTM-AESe），以及MTM、AESe搭配四轮转向、增强阻尼与降低助力转向的组合模式（MTM-AESe-4WS）。试驾后问卷调查结果显示，相较于基准模式，三种MTM相关模式下的驾驶员感知运动感显著提升，但危险感知无明显差异。进一步分析表明，相较于基准模式，MTM模式下车辆加速度显著升高，且超过110公里/小时限速的驾驶时长占比亦有所提升（效应量较小），但弯道行驶速度无明显变化。与基准模式相比，AESe模式对驾驶员的感知运动感、危险感知及驾驶速度均无显著影响。本研究结果表明，驾驶员的行为适应性是一种功能性且兼具机会主义特征的现象，而非由感知运动感或危险感知所介导。