ATSSA Innovation Update



The American Traffic Safety Services Association (ATSSA) Midyear meetings were held this year in Chicago, August 24th through the 26th. The Innovation Council meeting was especially interesting. Council Chairman Scott Covington along with several council members continue to work to make our voice heard in the automated & autonomous vehicle world (see August 1st post).

This year’s meeting included two great presentations. The first was by Lee Cole of Oldcastle Materials. Oldcastle is a large road building contractor with operations throughout North America. They suffered a series of work zone crashes that injured and even killed their workers and Mr. Cole was charged with finding a way to mitigate work zone intrusions.

The result is a system they call AWARE: Advance Warning & Risk Evasion. It was developed by the military to reduce casualties from roadside bombs and shoulder fired rockets. But the same tracking software was adapted to track vehicles approaching the work zone and through several complicated algorithms, determine if those vehicles would pass by safely, or if they might travel into the work area.

They are testing the system with eight paving crews this summer and hope to expand the program soon.  The system appears to be very cost-effective. And it is designed to avoid false alarms while  still giving workers time to get out of the way when intrusions do occur.


The second presentation was made by Jon Kruger, District Construction Director for Indiana DOT. Mr. Kruger began by saying his focus is on building roads. He didn’t know anything about work zone ITS systems a couple of years ago. But when they began work on several miles of I-94 near Chicago, he was asked to look at ways to mitigate impacts to traffic. They chose a queue warning system and it has worked out very well.

He now requires these systems on most of his paving projects. He said they do so 70% for safety and 30% for the data they generate. He said queue lengths are very unpredictable. He saw a big discrepancy between predicted queue lengths and actual. Volumes varied widely and alternate routes played a big role in that by drawing traffic away from the affected areas. They have even adjusted work windows when their real time data shows it is justified.

Neil Boudreau, the state traffic engineer for Massachusetts DOT agreed with Jon saying that they use the data they collect on each project to build a database. Eventually they will learn what happens when a certain type of project is performed on a particular route, or in a particular area. They then hope to have a more precise idea of when lane closures should be allowed and when they should not.


If you are involved in traffic engineering or with autonomous and automated vehicles, consider becoming involved with the ATSSA Innovation Council. They have become the point at which those two worlds interact with our work zone communityto make our roads safer.

The Automated Vehicles Symposium from a Work Zone Perspective


The Work Zone ITS Blog attended the Automated Vehicles Symposium in San Francisco July 20th. We came away with a very positive impression of the state of this practice. In previous posts we have expressed a concern that autonomous vehicle (AV) design must take work zones into consideration early in the process. That now appears to be the case. Work zones were mentioned in many of the plenary sessions along with the need for their systems to operate safely within them.

Breakout Session #20 – “Physical Infrastructure, Work Zones, and Digital Infrastructure” discussed this issue in more detail. Ross Sheckler of iCone explained the special problems inherent in work zones. We will get into his presentation in more detail in a future post, but he opened a lot of eyes. Audience members were asking questions, taking abundant notes, and were otherwise very engaged in the topic.

This means, of course, that we have their attention. It is good that we as the work zone industry have gotten involved. Now we need to make the most of it by making ourselves heard in this and other AV events.

As you may be aware, there is still a lively debate over two topics: 1) DSRC versus 5G communications, and 2) Whether automakers should include level 2 automation in production vehicles. Both of these topics are important to the work zone industry.

Let’s start with the communications issue. 4G is the digital wireless network you already use for your smart phone.  This is what we use today to control message signs and to upload portable sensor data.  A faster version known as 5G is rolling out in many areas. DSRC or Dedicated Short Range Communications is a radio spectrum (5.8 ghz) set aside, at least for now, for the exclusive use of the transportation industry. DSRC is faster and doesn’t have the latency problems associated with 4G. Vehicle to vehicle warnings occur instantly so if a car tells the one behind it that it is about to stop, the one following will get that warning soon enough to stop safely as well.

For most work zone applications 4G/5G works just fine. So manufacturers will likely stick with that. But if DSRC becomes more popular changes to our systems may become necessary. Work zone system designers should take this into consideration.

Level 2 automation is more of a problem. It is a suite of systems including adaptive cruise control, lane keeping, etc. that allows drivers to relinquish control for a period of time, say as they are driving on a freeway from one town to another.

The Tesla driver killed recently was using level 2 automation. He died when his car ran under a big rig turning in front of him. But he could as easily have run through a work zone. So this stage in automation must relinquish control automatically when approaching work zones. And it must do so early enough for the driver to take control and drive for enough time to regain his or her situational awareness. Human factors studies are just beginning to look at this, but it is clear this may take a minute or two. So on freeways, control would have to switch to the human driver at least two miles prior to the work zone.

How this will be accomplished is not yet clear. If all work zones are logged in real time into a central database such as a travel time system, it could be used to toggle control. Or perhaps a device mounted in the first message sign (normally located a couple of miles upstream of the work zone) could do the same thing.

These are all important and must be settled before AV technology can become mainstream. Events like the Autonomous Vehicle Summit will help move these conversations forward. So get involved and ensure that work zones are part of the discussion.

Will Pokémon Go Kill DSRC?

PokemonIf you have been paying attention at all during the past few days you have heard about the new game Pokémon Go. It is what is called an augmented reality game. It is wildly popular. Tens of millions have already downloaded the game in its first week. They wander around looking at a Google Earth image of their location that allows them to see and perhaps capture mythical creatures known as Pokémon.

What I found interesting is that the game is written. It works fairly well and will only get better with time. It is available in both iOS and Android versions. This will be a huge boost for 4G/5G V2X communications and may be a nail in the coffin for DSRC.

Think about it! Instead of Zubats, Pidgey, or Paras (varieties of Pokémon), imagine placing work zone devices in this virtual reality. Virtual cones and arrow boards would mark the exact spot where a work zone taper begins. Message signs could display the messages currently displayed on the corresponding message signs in the real world. And all of that information could be displayed in real time in vehicles approaching that location.

This could also be done in what you might call the opposite direction. Augmented WorkzoneA traffic control technician could be sent into the field with his S7 Android phone. Once he gets to the work area he wakes up his phone, clicks on the work zone app, and a Google earth image of what he is looking at in the real world pops up. But that image shows the work zone already set up. It might show the messages for the message signs. It would be very easy to place each advance sign where it belongs. Just look at the buildings, trees, etc on the virtual display and place the ROAD WORK AHEAD sign in the real world where it shows on the virtual display.

Traffic control plans would become a virtual reality file that designers would use to fit their plans to the real world conditions. Once done, it should work perfectly in the real world. It is like Computer Aided Design/Computer Aided Manufacturing – what you draw is what you get!

But I digress from my earlier point and it is an important one. Augmented reality is here. It is working on digital phones on 4G networks. There is no reason to start over again and do the same thing for DSRC. Granted, there are some applications where latency is an issue, like warning the vehicle behind you that you are about to stop, where DSRC still has advantages. But, thanks to Pokémon Go, I don’t believe infrastructure features such as we will need for work zones, will be working through DSRC.

Why Aren’t Queue Warning Systems Used On Every Project?

Those of us that have been in the work zone ITS industry for several years understand that agencies don’t change quickly. New technology must be tested and evaluated before it is used on a more regular basis. We get that. But we are now at the point where queue warning systems should be included on every project where frequent and dynamic queuing is expected.

WZcrashesStudies by the Texas Transportation Institute have shown a reduction in rear end crashes of as much as 45%. Crash severity is reduced as well. Other states including Illinois have also seen a dramatic decrease in crash frequency and severity.

These systems are inexpensive and the benefits are substantial. Avoid just one lawsuit by using queue warning and that savings will more than pay for the cost of the system. So it does not matter how long the project lasts. Projects lasting only a few days could deploy a system for something like $700 per day.Projects months long would pay something like $10,000 per month. Those prices include the sensors, message signs, communications costs, design, set-up, etc.

One law suit will cost tens if not hundreds of thousands of dollars.  It really is that simple. And that doesn’t take into account all of the other benefits. Fewer crashes mean the project is completed faster. Motorists are happier with the DOT because they aren’t experiencing long delays. And you will have the data to meet the Federal Work Zone Safety & Mobility Rule requirements for work zone performance measurement.

There has been progress. Texas is moving toward statewide use of queue warning systems. Illinois is also. Several other states are working on following suit. But most states only use them on special high impact projects. Some don’t use them at all.

So, I really do want to know. What is holding you state folks back? Why don’t you use these everywhere? I sincerely want to know. Please comment on this post. Let’s talk about it. Perhaps as a group we can find ways around the road blocks you face. And together we can significantly reduce the single largest cause of work zone fatalities nationwide.

Portable Traffic Signals as Work Zone ITS?

20160623_065843Today there are many definitions of work zone ITS. I’ve always felt that just because a device is controlled by electronics and some amount of internal software, does not qualify it as work zone ITS. Good examples are portable changeable message signs or portable traffic signals. In their simplest form they work independently and do not react to their environment.

But recently we started a project with portable signals that should qualify. Before the job bid we suggested portable signals as a cost-effective alternative to hardwired temporary signals mounted on posts and powered by a generator. The agency agreed but asked for most of the optional features mentioned on Horizon’s website. Those included wait time display, drive way assistance device, emergency vehicle preemption, and remote monitoring and notification.

Let’s look at each of these in a little more detail.

The wait time display is a changeable message sign attached to the articulating arm of the signals. When the signal at the other end of the work zone is green, the one facing stopped traffic tells it the maximum time they can expect to wait. Then, once the signal on the other end goes to red, it displays a countdown to green equal to the remaining clearing time.

This is a great feature when the work zone is especially long or when drivers on one end of the work zone cannot see the other end. Like travel time systems, once drivers know what the wait time is, they don’t seem to mind it as much. But not knowing often upsets them.

20160623_065949The driveway assistance device is another clever addition. The display consists of a red light and two flashing red arrows, one pointing right and the other left. When the light is red, drivers are expected to stay put. But when the right arrow is flashing, they can turn right when it is clear. The device ties into the signal phases on the main line. The system knows when traffic is moving to the right and tells the driveway assistance device to inform any drivers there that they may do so, too. It’s similar to a WAIT FOR PILOT CAR sign, but starts the moment traffic is cleared to go in that direction.

Emergency vehicle preemption is the same as most permanent signals use. It immediately turns the signal on the other end red, but still must give the same clearance time before turning to green for the ambulance or fire truck. Because these signals are farther apart, sometimes a half mile or more, the emergency responder must still sit there until traffic clears. Otherwise the potential for conflicts exists. This is one feature I would not recommend again, except when the signals are set up for a conventional intersection where clearing time is minimal. Or when there is an especially high volume of traffic that would otherwise extend the green time without preemption.

Remote monitoring is just what it sounds like. The signals report to a server over a wireless digital modem. All aspects of signal operation are monitored. If a lamp fails, or power drops, or communications between signals are lost; an alarm is sent to everyone concerned via text or email. Signal operations are also logged with each phase date & time stamped. So if a motorist claims they were green when they were actually red, the agency would be able to prove that.

Traffic engineers have taught drivers to expect traffic signals to do certain things. Portable signals can now do anything that permanent ones can do. That reinforces those lessons and makes our work zones safer.

Adapting Existing Technology to Unusual Traffic Problems

The work zone ITS industry has produced many creative ways to help mitigate the impacts to traffic from work zones and to protect workers from that same traffic. But often the problems we solve aren’t the same ones we set out to address. This is true for most industries when they encounter new technology.

According to author H. W. Brand it was true for the movie industry as well. When the first “talkies” were released, “Sam Warner (of Warner Brothers’ fame) convinced his brothers to purchase a technology that allowed the attachment of sound to recording film.” “The initial appeal was that sound would permit theaters to dispense with the orchestras that played accompaniment to otherwise silent films.” Today we can’t imagine movies without the sounds of explosions, gun fire, and, of course, dialogue.  But they were focused on the economic benefits of the technology and so missed what we all see as the obvious artistic advantages.

The same is often true in our industry. Our technologies are more mature now, though new ideas are introduced every day. But too often we miss good opportunities to improve the safety or efficiency of our roads because we don’t have a prepackaged system ready to deploy.

In fact, we do have them ready. We just don’t think it through far enough. Most of our systems use sensors to measure traffic flow, then compare that data to a set of rules, which then trigger outputs like messages to message signs, or alarms at a traffic management center. So it does not matter what your traffic concern is, a system can probably be created to address it. And while such a system could be called “custom”, it won’t normally be saddled with the costs and lead times normally associated with custom systems.

Redding Map

A good example was a demo project done for Caltrans a few years ago. They were closing one of their busiest ramps in Redding for reconstruction. The plan called for them to send traffic to alternate ramps. But no one of those was capable of handling the volumes at the closed ramp. Road-Tech proposed a simple solution. A sensor was placed on each of the alternate ramps. And portable changeable message signs directed traffic to the best alternate. As traffic backed up on the first alternate ramp the sensor detected the stopped traffic. That caused the system to change the message signs to recommend the second alternate ramp. If that ramp backed up traffic was sent to a third alternate ramp.

It was simple, inexpensive, and worked very well. The only problem encountered was public outreach efforts scared everyone away. So the volumes were never as high as expected. But this does show what can be done with the tools we already have. No one talks about alternate ramp systems. But it turns out we had one ready to go. We just didn’t know it.

Next time you are faced with a traffic problem, try to imagine a rule. That rule would say, “If traffic does X, make Y happen.” So if traffic slows I want to change the message signs to warn of STOPPED TRAFFIC AHEAD. Or if average traffic speeds exceed 75 MPH, I want to send an alarm to the police department. If you can come up with a rule, a solution is probably already available. Keep that in mind and you’ll be surprised what can be done!