The advent of autonomous vehicle technologies and the emergence of new ride-sourcing business models has spurred interest in Automated Mobility-on-Demand (AMOD) as a prospective solution to meet the challenges of urbanization. AMOD has the potential of providing a convenient, reliable and affordable mobility service through more competitive cost structures enabled by autonomy (relative to existing services) and more efficient centralized fleet operations. However, the short and medium-term impacts of AMOD are as yet uncertain. On the one hand, it has the potential to alleviate congestion through increased ride-sharing and reduced car-ownership, and by complementing mass-transit. Conversely, AMOD may in fact worsen congestion due to induced demand, the cannibalization of public transit shares, and an increase in Vehicle-Kilometers Traveled (VKT) because of rebalancing and empty trips. This study attempts to systematically examine the impacts of AMOD on transportation in Singapore through agent-based simulation, modeling demand, supply and their interactions explicitly. On the demand side, we utilize an activity-based model system, that draws on data from a smartphone-based stated preferences survey conducted in Singapore. On the supply side, we model the operations of the AMOD fleet (including the assignment of requests to vehicles and rebalancing), which are integrated within a multimodal mesoscopic traffic simulator. Comprehensive simulations are conducted using a model of Singapore for the year 2030 and yield insights into the impacts of AMOD in dense transit-dependent cities from the perspective of the transportation planner, fleet operator, and user. The findings suggest that an unregulated introduction of AMOD can cause significant increases in network congestion and VKT, and have important policy implications that could potentially inform future deployments of AMOD.

自动驾驶汽车技术的出现和新的乘车出行商业模式的出现激起了人们对自动按需机动性（AMOD）的兴趣，这是一种应对城市化挑战的前瞻性解决方案。AMOD可以通过更具竞争性的成本结构（相对于现有服务）和更高效的集中式车队运营来提供更具竞争力的成本结构，从而提供便捷，可靠和负担得起的出行服务。但是，AMOD的短期和中期影响尚不确定。一方面，它有可能通过增加乘车共享和减少汽车拥有量以及补充公共交通来缓解交通拥堵。相反，AMOD实际上可能会由于诱导需求，公共交通份额的蚕食而加剧交通拥堵，以及由于重新平衡和空行程而导致的行车里程（VKT）的增加。这项研究试图通过基于代理的模拟，明确地建模需求，供应及其相互作用来系统地研究AMOD对新加坡运输的影响。在需求方面，我们利用基于活动的模型系统，该系统借鉴了在新加坡进行的基于智能手机的陈述式偏好调查中的数据。在供应方面，我们对AMOD车队的操作进行建模（包括对车辆的请求分配和再平衡），这些操作已集成在多模式介观交通模拟器中。使用新加坡模型对2030年进行了全面的模拟，并从交通规划者的角度洞悉了AMOD在依赖交通的密集城市中的影响，车队运营商和用户。研究结果表明，不受管制地引入AMOD可能会导致网络拥塞和VKT显着增加，并且具有重要的政策含义，可能会为将来的AMOD部署提供信息。