Vehicle automation, micromobility, curbside management, future transportation, and land use relationships were key topics within various TRB sessions. Many of the discussions addressed travel safety, particularly involving automated vehicles and conflicts with pedestrians, other vehicles, and bicycles, along with other forms of micromobility.
As in previous years, funding of transportation improvements and the use of road pricing to manage travel demand were also of key interest.
Many of the transportation industry’s activities at this time involve private-sector research, initiatives, and products (particularly related to automated vehicles, vehicle ride applications and micromobility services). The Consumer Electronics Show (CES) in Las Vegas, typically occurring the week before TRB, has become the focus for many private sector transportation professionals as well as USDOT.
TRB remains important as a conference that focuses on university and public research activities, in particular, research that addresses transportation policies, as well as how to integrate new technologies within public sector management and operations, along with addressing impacts on safety, mobility, and the environment.
The popular “unconference” that kicks off TRB week invites participants to propose session ideas on the fly. This year featured more speakers seeking dialogue and feedback on projects and ideas (as opposed to presentations). For example, Deputy Director, UCLA Institute of Transportation Studies, Juan Matute presented early research on curbside management and the potential for micropayments.
The all-day event also featured a new app release for “OurStreets”, available on Apple devices. The app allows citizens to report street conditions. TransitScreen also rolled out CityMotion as an app that aggregates all travel options in one place (mobility as a service, or MaaS app).
Speaking of MaaS, there is increasing scrutiny of how services are bundled. In Europe, MaaS is offered as subscriptions, including “all you can eat” travel on transit plus and an array of shared-use options like bikeshare and ridehail (e.g., Uber and Lyft).
Early results show this can lead to induced demand and inefficient travel patterns. In America, the preferred MaaS model is the ability to find the best travel options within one mobile app with seamless payments. This is already occurring within Google Maps and the Lyft app, which shows transit information in some cities.
CAV and ITS: Some Underlying Themes
While there are numerous committees that have some overlapping yet distinct perspectives (Freeway Operations, Managed Lanes, Vehicle-Highway Automation, ITS, Regional Transportation Systems Management and Operations), there were several overarching themes in the various sessions and committee meetings that are carrying transportation into an uncertain yet exciting future:
- Safety is clearly the number one priority for most of the Federal and research community. The high-profile crashes involving Tesla and Uber have made algorithms for automated driving systems an critical importance. In particular, a presentation by the Dutch Safety Board during one of the automated vehicle workshops reviewed a variety of crashes involving automated driving assistance systems (ADAS) that require some level of driver interaction, and their conclusion was that if vendors cannot get ADAS right, despite all the effort that has gone into them, full vehicle automation (involving no driver or driver interaction) will not be a safe option. USDOT and others have generally separated ADAS from higher-level automation, but in general, there is now a significant concern about ADAS issues having significant implications for the more extensive automation efforts.
- Classification of roads and streets in order to establish their preparedness for CAVs is an area currently under research, taking into consideration electronic, communications, and geometric considerations. As part of a workshop on CAV impacts on road geometrics, breakout sessions addressed preparedness of the road infrastructure for CAVs. Several comments and considerations were raised:
- “Traffic is a social dance”: how do we teach robot cars to dance like humans in the same situation?
- How do we address “exceptions” like double parking, weather?
- How do we manage the relationship of automated vehicles with pedestrians, bicycles, and scooters?
- Operations/mobility vs. safety orientation: there seems to be an ongoing battle on what is most important.
- Given the vehicle population for the foreseeable future will be a mix of human-operated and automated vehicles, the public sector generally believes the ability for communication between vehicles will be important in order to maintain safety. Specifically, there needs to be interaction with the roadside traffic control and information infrastructure (i.e., “traditional” components) such as traffic signals. Some recent actions by USDOT are bound to change the approach being taken:
Since 1999, the Federal Communications Commission (FCC) had set aside a “Transportation Bandwidth” (5.85-5.925 GHz) focused on safety and mobility applications, utilizing a very low-latency protocol called Dedicated Short Range Communications (DSRC), indirectly based on Wi-Fi standards, providing vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) connectivity within 900-1000 feet of each vehicle or roadside hotspot.
However, several automakers and telecommunications providers have preferred compatibility with cellular data standards, and have developed a “Cellular V2X” technology enabling vehicle-to-cloud (V2C) communications, eventually migrating to newer cellular 5G technology, which includes a short-range wideband data capability with similar range to DSRC to support V2V and V2I. At this time, the technology does not have the low latency needed to support immediate collision warning messaging, although research and development are ongoing.
Recently, the FCC has revisited the use of the 5.9 GHz transportation bandwidth and issued a draft rule which would allocate 45 MHz to general wi-fi use, with 30 MHz reserved for transportation use. However, 20 MHz has been reserved for C-V2X and only a maximum of 10 MHz for DSRC, which could also be used for C-V2X.
This has effectively served as an implicit endorsement of C-V2X technology & 5G, and ITS America, AASHTO, and a number of states and other organizations have issued their opposition to the FCC proposed rule, claiming it would sacrifice traffic safety due to the elimination of bandwidth for the proven (but not commercially-supported) DSRC technology.
- The release of the Automated Vehicle 4.0 report jointly from USDOT and the President’s Office has essentially rolled back the development of any national operational or control standards for vehicle automation that would supersede any state or other standards – or of any functionality proposed by automakers or automated driving system vendors. It also implies 5G as the technology of the future for V2X communications.
- Major legal issues involve incident management (eg, laws involving putting out flares or warning triangles if a truck breaks down – what if stalled truck is driverless?)
Curbsides and Curb Management
This topic really took off this year with multiple tracks and sessions addressing the growing demand for curb and sidewalk space from e-commerce, ridehailing apps such as Uber, and micromobility.
- While there was a lot of research on curb use, speakers also addressed cities’ desire to move from hourly parking meters to micropayments from quick users such as food delivery services and package handlers. All noted this will be more complex than originally thought (even mapping streets and curbs is a challenge).
- As e-commerce grows, it’s clear cities will need a more holistic approach to managing deliveries and logistics. Urban planning and architecture will be key for designs that take activity off of busy streets. Speakers also noted how European freight companies are staging smaller delivery vehicles around a city since larger trucks require vast amounts of space for parking and maneuvering. One of the more intriguing presentations compared headline-grabbing e-scooter infractions with those of automobiles. In the study, 1% of scooters were improperly parked compared to 25% of automobiles.
Intelligent Transportation Systems (ITS): The use of advanced information and communications technologies to improve personal mobility and transportation safety. Cooperative ITS (also calledC-ITS) refers to the use of data from connected and automated vehicles (CAVs) as well as communication to CAVs in order to benefit the real-time operation of
the transportation system.
Automated (often called Autonomous) Vehicles (AV): Vehicles that are able to travel from an origin to a destination based on specific user requests received beforehand or during the course of travel, without requiring direct control input from a human driver. These are often referred to as Automated Driving Systems (ADS), not to be confused with ADAS (see below). SAE refers to ADS functionality as either Level 3, 4 or 5 systems, with Level 3 including the ability for driver intervention in an emergency not foreseen by the automated vehicle operation, Level 4 enabling automation with no driver input under most travel conditions (often within a fixed travel lane or operational scheme, e.g., automated shuttle services, platooned trucks), and Level 5 enabling full vehicle automation under all road conditions and geometrics.
Automated Driver Assistance Systems (ADAS): Refers to systems that provide tools to assist human drivers with safe vehicle operations, including adaptive cruise control, “jam assist” (controlling vehicle operations during stop-and-go traffic), parking assistance, lane departure warning and steering correction, automated braking, and in-vehicle signing/traffic control displays. These generally are classified by SAE as Level 1 (automated functions requiring driver to maintain steering, throttle and braking control of the vehicle) and Level 2 (automated functions that enable the vehicle to take over steering, throttle and braking control from the driver when required to avoid a crash).
Connected and Automated Vehicles (CAV): Also referred to as Cooperative ITS (C-ITS), this refers to vehicles with the capability of providing data to the roadside, to operational centers and service providers, and to other vehicles; and also the ability of these vehicles to receive data from those other entities and in an automated fashion (using ADS or ADAS functions), react to conditions in combination with on-vehicle sensors that detect conditions around the vehicle. The basic building block consists of wireless “V2X” communications (see below).
Cooperative Adaptive Cruise Control (CACC): Involves Adaptive Cruise Control (ACC), the ability to adjust travel speeds of a vehicle using LiDAR or other sensors based on the speed of the vehicle traveling in front; the “Cooperative” element obtains acceleration or deceleration rate data from the vehicle in front using V2X communications to reduce ACC reaction times.
V2X Communications: Refers to wireless communications between vehicles and infrastructure (V2I), between two or more vehicles (V2V), and between vehicles and operational centers or service providers via the cloud (V2C). V2X is the basic building block of connected vehicle communications used by CAVs (also known as C-ITS as discussed above). V2X communications generally can be accomplished as follows:
- Through Dedicated Short-Range Communications (DSRC), a wireless medium based on IEEE standard 802.11 (wi-fi) that operated in the 5.85-5.925 GHz range, utilizing in-vehicle On-Board Units (OBUs) and Roadside Units (RSUs) which serve as hot spots.
- Through Cellular (C-V2X) communications, which utilize cellular data standards (currently 4th generation Long-Term Evolution, or LTE, evolving in the near future to 5th Generation, or 5G cellular communications). OBUs and RSUs for C-V2X would be required to utilize leased channels for C-V2X communications, which for 5G would involve both short-range (analogous to DSRC but not compatible) and long-range (similar to but with more bandwidth than LTE) communications.
- A number of interim C-V2X deployments are utilizing RSUs and OBUs that can work with both DSRC and cellular connectivity.
Mobility as a Service (MaaS): Refers to an application that integrates real-time information and payment resources for multiple transportation modes and services, ranging from parking to transit fare payment or passes to rental of shared micromobility, e.g., scooters, bicycles.