Multimodal operation of smart intersections
This PhD research project aims to develop a model/platform that can utilise real-time feeds of all mode movements from our smart intersections and optimise the signal control to minimise safety risks, all while maintaining an efficient flow of vehicular traffic at the network level.
Urban intersections are major bottlenecks in our transport network. Effective control and efficient operations of our intersections play a significant role in:
- Reducing traffic congestion and its negative impact on our economy and environment, and;
- Improving roadway safety not only for private cars but also for all other modes of transport, including vulnerable road users.
In the current research within the Australian Integrated Multimodal Ecosystem (AIMES), Melbourne University has installed advanced mobility sensing devices at multiple intersections within a 6 square-kilometre zone in the Melbourne central district.
These sensors include:
- High-definition cameras connected to edge-computing devices
- Induction loops
- LIDAR sensors
- DSRC devices
- Mobile Wi-Fi detectors
- Bluetooth readers
Collectively, these will enable us to detect, classify, and register vehicular traffic movements (including trams, buses, trucks) and vulnerable road users (pedestrian and cyclists) crossing or waiting at intersections with a high precision and in real-time.
With increasing popularity of active and sustainable travel modes and emerging shared mobility alternatives, including ride-hailing and ride-sharing services, electric and shared bike/scooter systems, our urban transport is bearing a paradigm shift in roadway space utilisation.
This is definitely a positive transition to multimodal and sustainable use of transport resources; however, the shared use of roadway space introduces inevitable and new conflicts among different modes and significant safety risks, traffic jams and delays to all road users.
The transport infrastructure of the future should be capable of accommodating the multimodal travel demands efficiently. At the centre of transport infrastructure lies the smart intersection that should ideally serve the following essential functionalities and objectives:
- A safe intersection where users from all modes can utilise the shared space and traverse without safety risks. In a connected transport system, real-time sensor and communication technologies can help minimise risks of collisions, especially for vulnerable road users that are shown to over-represent in serious and fatal crashes.
- An efficient intersection where optimal right-of way is allocated to competing movements at the intersection. With the advent of real-time traffic counts by all modes, optimisation of intersection control can be achieved to maximise throughput of users at the intersection. Internet of Things and real-time data from individual intersections would also facilitate network level traffic management to prevent the onset of congestion by controlling upstream flows and spreading the traffic volumes over time and space.
- A healthy intersection where a proper right-of-way is allocated to active modes of transport, including pedestrians and cyclists. Minimising heavy vehicle emissions from stop-and-go at traffic lights should also be considered as an objective to minimise negative health impact on all users.
- An accessible intersection where sufficient right-of-way is allocated to individuals with mobility impairment. This could include prolonged green times for wheelchairs, individuals with walking assistance and elderly who walk slower.
- A sustainable intersection where active and low-footprint modes of transport are prioritised and promoted. Public transport should be prioritised by green light extensions and early greens, and similar right-of-way should be allocated to cumulating crowds of cyclists, pedestrians and batch arrival of passengers from public transport.
Every intersection, depending on geometric design and functional type, position in the network, and neighbourhood land use, may display different patterns of usage and conflict between competing multimodal demand within and across days. Some intersections are dominantly used by private vehicles and some accommodate multimodal travellers.
Depending on time of day and location, some intersections may also bear a heavy weight from freight trucks and heavy vehicles. Depending on patterns of users and demand volumes, urban intersections may expose their users to different levels and types of safety risks and travel delays.
Insights into traffic volumes, flow/delays, potential conflicts, safety risks and near miss experiences carried out for individual intersections can shed light on what types of interventions are essential and what pieces of technology can serve those needs most effectively.
In the current research within the Australian Integrated Multimodal Ecosystem (AIMES), Melbourne University has installed advanced mobility sensing devices at multiple intersections within a 6 square-kilometre zone in the Melbourne central district. These sensors include high-definition cameras connected to edge-computing devices, induction loops, LIDAR sensors, DSRC devices, mobile Wi-Fi detectors, and Bluetooth readers that collectively enable us to detect, classify and register vehicular traffic movements (including trams, buses, trucks) and vulnerable road users (pedestrian and cyclists) crossing or waiting at intersections with a high precision in real-time.
In this project we aim to develop a comprehensive modelling framework to simulate and optimise multi-objective and multimodal operation and control of smart intersections. The proposed framework will be built in a simulated environment but based on real-time stream of traffic counts from all modes at multiple intersection in the AIMES testbed that are equipped with advanced mobility sensors for all modes.
Alternative objective measures will be investigated and proposed for multimodal operation of smart intersections and alternative trade-off methods will be proposed and simulated for inter-objective functionalities and optimal outcomes for all road users.
1. Develop a methodology for multimodal operation of individual intersections
A methodology of multimodal intersection operation will be developed, and alternative optimisation algorithms will be proposed and tested for operation and control of traffic signals in response to real-time traffic flows information.
2. Investigate and propose performance measures for alternative objectives of multimodal intersections
Our existing intersections are predominately aimed to optimise the throughput of vehicular traffic (only). With the vision that smart intersections of the future should accommodate multimodal, safety and sustainability objectives, research will be conducted to design performance measures to effectively evaluate the operations of intersection from safety and sustainability perspectives in addition to traffic efficiency objectives.
3. Investigate and propose reasonable trade-off methods for multi-objective operations
Research will be conducted to investigate and propose justifiable trade-off parameters for multi-objective operations of multimodal intersections.
Please note …
Ongoing, this page will be a living record of this project. As it continues, matures, hits milestones, etc., we’ll add information, links, images, interviews and more. Watch this space!