城市轨道交通FAO（全自动运行）系统通过信号、车辆、通信、站台门、综合监控等与列车运行相关专业系统的集成协同和联动控制，自动完成列车运行各种作业，正常情况下无需司乘人员干预。相比传统的人工驾驶系统，FAO系统提升了列车运行的自动化程度，具有安全、高效、灵活、经济、容易部署等特点。自1981年世界首例FAO系统——日本神户的港湾人工岛线开通以来，全球已有超过40年的FAO系统运营经验，国内也有10多年的FAO系统运营经验。据不完全统计，全球已有30多个国家和地区开通了110多条城市轨道交通FAO线路，总运营里程约为2 800 km，中国内地占比近1/3。据UITP（国际公共交通协会）预测，未来全球新建线路中将有75%的线路采用FAO系统，其中大部分增长将源于中国。据中国城市轨道交通协会统计，截至2023年底，中国内地共有21座城市开通了40多条FAO线路，运营里程为1 051.8 km，另外还有超过1 500 km的在建线路。   

纵观FAO系统的发展和运营历程，FAO系统的优点比较明显，能大幅提高运营可靠性，可避免因人为误操作而造成的安全风险，并提升人员工作效率。但是对于能否采用无人值守模式还有争议，存在FAO系统等同于无人驾驶的认识误区。虽然通过信号、车辆等核心系统的状态监测、冗余设计、自动处置等功能以及各子系统间联动耦合功能的增强， FAO系统的信息全面性和整体系统安全性得到了较大提升，但是，目前阶段还只是基本实现了正常运行过程无需人工操作，还不能完全实现运行全过程无人值守监护。有些FAO线路采用的是全过程无人值守监护模式，其中存在的安全风险需引起重视。这主要是因为FAO系统部分应用场景的安全防护仍未全面执行到位，如：故障情况下自动恢复或是远程排故还不够成熟，对线路运行环境感知功能和应急处置功能还不完善，运营管理体系和运维模式还不够健全。

如何进一步提升FAO系统的本质安全，持续提高效率，特别是实现非正常工况下高密度运行线路快速处置恢复，进而实现“运营故障无感”，与系统设计、建设质量、接口管理、风险管控、智慧运维、管理模式、标准规章等多个因素密切相关，是涉及多环节、多专业、多学科的复杂性系统工程，需要完善场景分析，加强风险研判和技术攻关，在以下几个方面持续探索实践和改进。   

一是开展系统性研究。从源头入手，开展设计、建设和运维的系统性研究，包括运营需求和场景分析、系统集成设计、专业接口管理、运行环境态势感知、系统集成联调联试、关键设备智能运维等；同时从风险入手，深入研判各种运营和维护工况的风险、乘客行为风险、环境因素风险，针对性设计风险管控的技术和管理措施。   

二是突破技术壁垒。深入研究信号、车辆、综合监控等相关系统的底层逻辑，积极应用人工智能等新技术，提升FAO系统的运行效率；不断优化列车、信号、供电和站台门等关键设备冗余设计，改进故障自动隔离与修复功能或是远程处置功能，确保设备运行的高可靠性和稳定性；完善列车运行环境异物侵限风险场景分析，加快远距离障碍物主动探测装置研发与应用，降低行车安全风险；集成研发站台门与车门的间隙探测系统，解决不同技术手段的监测盲区，控制夹人夹物的安全风险。   

三是完善运维管理体系。提升FAO系统运行安全与效率，不仅仅依托FAO相关技术，还需要配套适用的运维管理模式，系统性研究不同规模下FAO线网的运维管理体系，包括建立运维的标准规章体系、安全风险管控体系和管理数字化支持体系等；根据线网中FAO线路数量设计运营调度和运维模式；根据运维模式完善岗位标准、岗序设计、岗位复合和人才培养等管理方式。   

FAO是我国城市轨道交通行业的发展方向，各专业领域都要把握FAO系统的本质安全，不断提高可靠性和效率，强化技术创新突破，促进城市轨道交通相关产业的进步和发展。各城市不管是老线改造还是新线建设要因地制宜选择FAO系统的技术方案，健全FAO运营管理体系，在确保运营安全的基础上，逐步提高运营效率，通过良好应用促进城市轨道交通FAO系统高质量发展。

Urban railtransit FAO (fully automatic operation) systems integrate and coordinateprofessional systems related to train operations, such as signaling, vehicles,communication, platform screen doors, and comprehensive monitoring, to achievefully automated train operations without driver intervention under normalconditions. Compared with conventional manual driving systems, FAO systemselevate the automation level of train operations and are characterized bysafety, efficiency, flexibility, cost-effectiveness, and ease of deployment.Since the launch of the world′s first FAO system in 1981—the Port Island Linein Kobe, Japan—the global FAO system has accumulated over 40 years of operationalexperience, with over a decade of such experience in China. According toincomplete statistics, more than 30 countries and regions worldwide havelaunched over 110 urban rail transit FAO lines, with a total operating mileageof approximately 2,800 km, nearly one-third of which is in mainland China.According to the International Association of Public Transport (UITP: UnionInternationale des Transports Publics), 75% of newly-built lines globally areexpected to adopt FAO systems in the future, with the majority of this growthstemming from China. Statistics from the China Association of Metros revealthat, by the end of 2023, over 40 FAO lines has started operation in 21 citiesin mainland China, with an operating mileage of 1,051.8 km, alongside over1,500 km of FAO lines under construction.

Examining thedevelopment and operational trajectory of FAO systems, their advantages areevident: significantly enhancing operational reliability, mitigating safetyrisks caused by manual operational errors, and improving workforce efficiency.However, there remains debate over the feasibility of adopting a fullyunattended operation mode, and a misconception persists that FAO systems areequivalent to driverless operations. While the information comprehensivenessand the overall safety of FAO systems have greatly improved through functionsof core systems such as signaling and vehicles, including status monitoring,redundancy design, automated handling, and enhanced interconnectivity betweensubsystems, these systems have only been automated to the extent of maintainingnormal operation without manual intervention. The end-to-end unattendedoperation with supervision is not fully realized. Some FAO lines operate undera fully unattended and supervised mode, but the associated safety risks warrantattention. These risks arise primarily because safety measures for some FAOapplication scenarios have not been comprehensively implemented. For example,automatic recovery or remote troubleshooting during faults is not fullydeveloped, environmental perception and emergency handling capabilities forline operations remain incomplete, and operation-management frameworks andoperation-maintenance modes are not yet sufficiently robust.

How to furtherenhance the intrinsic safety of FAO systems and continuously improveefficiency, especially in swift handling and recovery of high-densityoperational lines under abnormal working conditions to achieve ′fault-imperceptibleoperations′, is closely related to many factors including system design,construction quality, interface management, risk management-control,intelligent operation-maintenance, management modes, and standards andregulations. It is a complex system engineering task involving multiple joints,disciplines, and subjects,that requires refined scenario analysis, strengthenedrisk assessment and judgement, and technological breakthroughs. The followingareas call for exploration, practice, and advancement.

First, carryingout systematic research. Challenges shall be addressed at their root, throughsystematic research on design, construction, and operation-maintenance,including operational needs and scenario analysis, system integration design,interface management of disciplines, operational environment situationperception, system integration and joint commissioning, key equipmentintelligent operation-maintenance. Simultaneously, taking risks as an anchorpoint, technologies and management measures on risk management-control shall bedeveloped with specificity by thoroughly investigating and assessing risksassociated with various operational and maintenance working conditions,passenger behaviors, and environmental factors.

Secondly,overcoming technological barriers. The foundational logic of related systemssuch as signaling, vehicles, and comprehensive monitoring shall be delved into,actively leveraging emerging technologies like artificial intelligence toenhance FAO system operational efficiency. The redundancy design of keyequipment such as train, signaling, power supply, and platform doors shall becontinuously improved and automated isolation and restoration/remote handlingduring faults shall be enhanced to ensure higher reliability and stability ofequipment operations. Scenario analysis of obstacle detection in trainoperation environments for intrusion risks shall be refined, and developmentand deployment of long-range obstacle detection systems shall be accelerated tomitigate operational safety risks. Gap detection systems shall be integrated andinnovated for platform screen doors and train doors to address monitoring blindspots caused by different technological means, thus reducing the safety risksof human/object entrapment incidents.

Thirdly,improving the OM (operation-maintenance) management systems. Enhancing theoperational safety and efficiency of FAO systems requires not only advancementsin FAO-related technology but also the complementary and applicable OMmanagement modes. Systematic research efforts shall be exerted on OM managementsystems for FAO line networks of varying scales, such as establishingframeworks for standardized OM regulation, safety risk management-control, anddigitalized management support. Operational dispatch and OM strategies shall bedesigned in alignment with the number of FAO lines in the network. Jobstandards, post hierarchies, multi-responsibility positions, and talenttraining program shall be refined according to the OM modes.

As a futuredirection for China′s urban rail transit industry, FAO systems require allprofessional fields to leverage the intrinsic safety of FAO systems whilecontinuously improving reliability and efficiency, fostering technologicalinnovation and promoting advancements across related industries. Whetherretrofitting existing lines or building new ones, cities should adopt technicalsolutions involving FAO systems that suit local conditions, establishcomprehensive FAO operational management frameworks, and prioritize safety as afoundation for improving operational efficiency. Through thoughtfulapplication, the high-quality development of urban rail transit FAO systemswill be promoted.