Special Interview with ATC Chief Engineer Paul Milazzo: SCATS System to Provide Cloud Services, Achieving Remote Signal Optimization

with ATC Specialist Paul Milazzo

Image Source | (© Javaistan | pixabay)

The SCATS system has been studied by the New South Wales Main Roads Authority in Australia since the 1970s and was put into use in the early 1980s. At present, the SCATS system has been used at over 26000 intersections in 30 cities in China, including Shanghai, Hangzhou, Ningbo, Guangzhou, Suzhou, Shijiazhuang, Tianjin, and Sanya.

SCATS system has three distributors worldwide, ATC, QTC, and TYCO. Recently, China_7its exclusively interviewed Mr. Paul Milazzo, Chief Engineer of Aldridge Traffic Controllers Pty Ltd (ATC), on the linkage application of SCATS system with radar and lightning perception equipment; The latest technological research and development trends of the system were discussed at the 29th ITS World Congress in Suzhou, China, in 2023.

Image Source | ITS Australia

China_7its: In the past two years, China has used many new traffic collection devices. We know that the control algorithm of SCATS is designed based on coils. Has SCATS made algorithm adjustments to meet the actual usage needs of video, radar, and thunder vision collection devices?

A: The SCATS algorithm was initially based on coil design. The core concept of the SCATS system is to automatically adjust the green light time based on changes in traffic flow, in order to improve road traffic efficiency. 

Specifically, when the saturation is higher, it indicates a higher traffic flow and a shorter time interval between vehicles. The SCATS system will correspondingly increase the green light time to more effectively handle high traffic flow. This enables the system to automatically adapt to various traffic scenarios, ensuring smooth and efficient road traffic.

The coils play a crucial role in this process as they provide real-time vehicle spacing information, helping the system measure saturation and traffic flow conditions. This principle of self-adaptability is the core of the SCATS system, which intelligently adjusts signal lights to adapt to different traffic flow situations based on real-time data, thereby improving road traffic efficiency.

However, coil sensors are susceptible to damage, which may have an adverse impact on the normal operation of the SCATS controller, as the controller requires reliable detection data for traffic management. In order to compensate for the potential shortcomings of the coil, the SCATS system has adopted alternative detection methods, including radar and video detection. 

Video detection is more mature in applications, but it may also be affected by issues such as occlusion, especially in intersection situations. Radar detection is plagued by perception issues at low speeds but is an alternative option to coils. 

The SCATS system has made corresponding technical adjustments to address the issues of road obstruction and low-speed traffic.

Firstly, if coil sensors are used and detector data has been collected for a sufficient period of time (at least 3 months or preferably 6 months), the SCATS system can use historical data to replace the current demand for data, especially when the current data is not ideal. 

Secondly, the SCATS system introduces a sensor replacement mechanism to address sensor failure issues. For example, if a coil malfunctions, the system can replace it with data from adjacent coils to ensure that the data requirements are met.

In addition, the SCATS system team has recognized the importance of data fusion as a key step in improving system performance. Data fusion is the ability to integrate traditional and new sensor data, which helps provide more comprehensive traffic information from multiple data sources such as coils, radar, and video to better understand traffic conditions.

The number of traffic control intersections in Malaysia may reach thousands, and due to maintenance issues, they use methods such as video, LiDAR, or radar for detection. Video detection equipment is more mature and common there, but lidar and radar are also effective.

In Indonesian applications, it seems that video detection devices are more common, although coil detection technology is still used in some places. If the coil is a 100% detection reference, video detection equipment may be another effective choice. 

China_7its: China is currently actively and extensively encouraging innovation in the transportation field. Can you share the innovation of SCATS system in recent years?

A: The first item is SCATS Cornerstone, a software that supports the construction of smart cities and support Cooperative ITS functionality.

SCATS Cornerstone is an important innovation in the SCATS system, which provides unified key map information, lane topology data, including the physical layout of intersections, signal phase and light state data. 

These data standards adopt ISO standards to ensure interoperability between traffic management systems worldwide. The value of SCATS Cornerstone is to help the traffic management system better understand the intersection topology (the layout), which is critical to the effective performance of the traffic management system, modeling applications, and networking and autonomous vehicle.

Secondly, we also have an important innovation, namely "SCATS Data Insights", which will be launched in the next major version of the SCATS system. 

This product aims to make extracting data from SCATS systems easier and provide users with more comprehensive data insights. This will enable others to better view, understand, and use this data, thereby providing more information to improve traffic management. 

The third item is that the SCATS system plans to provide cloud based services in the next version to support smaller cities that do not have traffic engineering resources by allowing experts to manage SCATS for these smaller cities.

This change will bring multiple benefits. Firstly, it will provide the system with more real-time data to better support traffic management and vehicle road collaboration. Internationally, these data are usually considered public and allowed to be used by third parties, but in China, there are some obstacles due to legal and sharing mechanisms limitations. 

The reasons for migrating traffic management systems to the cloud are multifaceted.

Firstly, for small cities or regions where there are not many signal machines in the area, there is no need to build independent signal control command centers from an investment perspective. They often lack professional knowledge and resources in transportation engineering.

However, these cities also hope to benefit from the benefits of adaptive traffic control systems such as green wave control. Therefore, the main purpose of moving the system to the cloud is to lower the technical barriers for users in these areas, so that they can easily enjoy the advantages of adaptive signal systems without having to bear the complexity of system management and maintenance on their own.

In addition, cloud deployment can also solve the problem of talent and professional knowledge. Transportation engineering is not a widely popular field, and nowadays fewer and fewer people are willing to work in the same profession for a long period of time, leading to a shortage of transportation engineers.

Therefore, the goal of the SCATS cloud computing system is to provide users with more convenient professional services to handle the complexity of the system. This means that service providers can provide customers with services such as remote signal optimization, thereby lowering the threshold for professional skills and allowing more places to benefit from advanced traffic management technology.

This innovation has been tested and demonstrated in places such as Melbourne to evaluate the market's acceptance of cloud based traffic management systems. In addition, small cities in Southeast Asia have also shown interest in this, further demonstrating the potential opportunity to migrate signal control systems to the cloud. 

Fourthly, in some Asian cities, including China, the proportion of non motorized vehicles on the road is quite high, which poses a challenge to the algorithm operation of SCATS. We are considering expanding the application scope of the SCATS system to include different types of transportation such as pedestrians, bicycles, and electric vehicles. This is crucial for addressing the issue of fairness in transportation,

In addition Transport for New South Wales (TfNSW) who develop SCATS will soon be releasing a new user interface that is more intuitive and map based. The new User Interface is called SCATS Control Centre and provides a web based view of the road network and a highly integrated set of data and graphical features to show how well SCATS is coordinating intersections in a corridor to deliver the Green Wave of Traffic Signals.