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，是当车辆引入新技术时，驾驶员是否会产生行为适应——即驾驶速度出现加快或放缓的变化。本研究针对运动模式（sport mode）展开行为适应效应的探究，该技术可调整车辆的听觉系统、节气门映射、动力转向及底盘参数设置。基于现有研究文献，可提出两种对立假说：其一，运动模式可提升驾驶员的感知运动感，进而促使其加快车速；其二，运动模式可能使驾驶员感知到更高的危险程度，通过稳态调节令其降低驾驶速度。本研究依托试验赛道上的仪表化试验车辆开展实验，共招募31名驾驶员，要求其在不同运动模式设置下按照日常驾驶习惯完成行驶，设置包括基准模式（Baseline）、修改式节气门映射（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结合四轮转向、增强阻尼与降低动力转向助力的复合模式（MTM-AESe-4WS）。事后调查问卷结果显示，相较于基准模式，三种MTM相关模式的感知运动感均有所提升，但感知危险度并无显著差异。进一步分析表明，相较于基准模式，MTM模式下车辆加速度更高，且车速超过110 km/h限速的行驶时间占比也有所提升（效应量较小），但过弯车速未出现显著变化。而AESe模式相较于基准模式，在感知运动感、感知危险度及驾驶速度方面均未产生显著影响。上述研究结果表明，行为适应是一种功能性且机会主义的现象，并非由感知运动感或感知危险度介导产生。