VOA科学技术2024--Researchers: Smarter Vehicles Could Greatly Change Traffic Signals

Researchers say the rise of more smart and connected vehicles on American roads could lead to big changes for traffic signals.

The current U.S. traffic signal system has been in existence for more than 100 years. But experts are now studying ways to link technology-equipped vehicles to signal systems in an attempt to improve safety and traffic flows.

One research effort is led by a team at North Carolina State University. Engineering professor Ali Hajbabaie is the leader of that research. He told The Associated Press one major change that signal systems could see is different colored lights.

Most U.S. traffic signals currently include three lights to direct drivers at intersections²: red, yellow and green. But Hajbabaie said it might make sense to add a fourth color, possibly white.

This color could inform motorists when there is a large collection of self-driving vehicles in a particular area. When many self-driving vehicles are present, the additional light would signal other drivers to follow the lead of those vehicles.

"When we get to the intersection¹, we stop if it's red and we go if it's green," said Hajbabaie. "But if the white light is active, you just follow the vehicle in front of you."

The North Carolina State team estimated that such changes are likely years away. Hajbabaie said one reason for this is because this kind of system would require between 40 to 50 percent of all vehicles on the road to be self-driving.

Sandy Karp is a spokesperson for Waymo. Waymo is a self-driving vehicle company owned by Google's parent, Alphabet. She told the AP that Waymo had already launched ride-sharing services that use full self-driving vehicles in Los Angeles, California and Austin, Texas. Those services do not use a fourth traffic light.

In an email to the AP, Karp said she thought it was good that researchers are currently "thinking creatively" about ways to change traffic light signals to improve safety and traffic flows. However, she said that officials and companies should think very carefully before deciding on, and moving forward with, major infrastructure³ changes.

Researchers at the University of Michigan are also testing different methods. They have carried out a test program in an area outside the city of Detroit. Their research collects data on the speed and location of General Motors (GM) vehicles in the area. The data has been used to change the timing⁴ of city traffic lights in an effort to improve traffic flows.

Henry Liu is a civil engineering professor at the University of Michigan. He helped lead the research. He said the launch of a new U.S. traffic system could be a lot closer than people might think.

Liu said that even with as few as 6 percent of vehicles connected to the GM system, there is still enough data to change the timing of the traffic lights enough to smooth traffic flows.

The area near Detroit where the testing is taking place has 34 traffic signals. It was chosen because lights in the area are set to change at the same times each day. This is the case for more than half of traffic signals nationwide. These signals are not connected to cameras or sensors⁵ to watch traffic flows in real time.

Liu noted⁶ that higher-tech solutions will require cities to make complex and costly⁷ investments.

"The beauty of this is you don't have to do anything to the infrastructure," Liu said. "The data is not coming from the infrastructure. It's coming from the car companies."

Danielle Deneau is the director of traffic safety at the Road Commission in Oakland County, Michigan. She said results of the University of Michigan research changed the timing of green lights only by a few seconds. However, Deneau added, even that was enough to improve traffic flows.

Words in This Story

intersection - n. the place where two or more streets meet or cross each other

infrastructure - n. the system of public works of a country, state, or region; also : the resources (such as buildings or equipment) required for an activity

location - n. the place or position where something happens

1 intersection   

n.交集，十字路口，交叉点；[计算机] 交集

参考例句：

• There is a stop sign at an intersection.在交叉路口处有停车标志。
• Bridges are used to avoid the intersection of a railway and a highway.桥用来避免铁路和公路直接交叉。

2 intersections   

n.横断( intersection的名词复数 )；交叉；交叉点；交集

参考例句：

• Traffic lights have been placed at all major intersections. 所有重要的交叉路口都安装了交通信号灯。
• Intersections are of the greatest importance in highway design. 在道路设计中，交叉口占有最重要的地位。 来自辞典例句

3 infrastructure   

n.下部构造，下部组织，基础结构，基础设施

参考例句：

• We should step up the development of infrastructure for research.加强科学基础设施建设。
• We should strengthen cultural infrastructure and boost various types of popular culture.加强文化基础设施建设，发展各类群众文化。

4 timing   

n.时间安排，时间选择

参考例句：

• The timing of the meeting is not convenient.会议的时间安排不合适。
• The timing of our statement is very opportune.我们发表声明选择的时机很恰当。

5 sensors   

n.传感器，灵敏元件( sensor的名词复数 )

参考例句：

• There were more than 2000 sensors here. 这里装有两千多个灵敏元件。 来自《简明英汉词典》
• Significant changes have been noted where sensors were exposed to trichloride. 当传感器暴露在三氯化物中时，有很大变化。 来自辞典例句

6 noted   

adj.著名的，知名的

参考例句：

• The local hotel is noted for its good table.当地的那家酒店以餐食精美而著称。
• Jim is noted for arriving late for work.吉姆上班迟到出了名。

7 costly   

adj.昂贵的，价值高的，豪华的

参考例句：

• It must be very costly to keep up a house like this.维修这么一幢房子一定很昂贵。
• This dictionary is very useful,only it is a bit costly.这本词典很有用，左不过贵了些。