Data Latency and Work Zone ITS

We met recently with a large local agency to discuss the idea of connected work zones and the concept of reporting work zones in real time to the digital maps we all use to get from Point A to Point B. She was excited about the idea but had concerns about delays that are sometimes experienced between the time when an incident occurs and the time when it is reported to you by your navigation app.

According to Waze, 65 million drivers regularly use their navigation service to get home as quickly and efficiently as possible. Drivers want to know about problems along their routes before they reach them and in time to take another faster route if it makes sense to do so. Richard Russell, a former sales engineer with Google, said five years ago that, “we actually want negative latency, and will perceive anything less as latency.”

That was about the time that Google purchased Waze. Waze works because users report problems in real time thus helping to reduce latency. HERE has found another way to reduce latency. They look at in-vehicle sensors such as hard braking sensors to identify and locate traffic issues the moment they begin. HERE also plans to begin including user reports to get as close to real-time reporting as possible.

Today, work zones are the single largest cause of non-recurring congestion. So, if we could report work zones in real time (see Work Zone Reporting to Autonomous Vehicles – posted 9/25/18) it will make these services even more valuable. Imagine arrow boards equipped with a device to report location and display status every time it is turned on or off!

Yet how will these services process an unimaginable amount of data including location, date & time, type of incident, and some form of verification and get it to the user without at least some delay? That is a problem only Waze or HERE can answer. We can tell you they are working on it.

In the meantime, some small amount of latency (a few seconds to as much as a minute) is going to exist. But the service is still valuable. In today’s worst-case scenario Driver A leaves home and asks for the fastest route to work. The app recommends the best one based on conditions at that time. Perhaps moments earlier an arrow board was turned on when a contractor closed a lane along that route for maintenance work. A short time later the app reports that roadwork and reroutes Driver A along a now preferable route. The app still saves him time, just not quite as much time as it might have with instant knowledge of all work zones.

Zero latency is the goal. But let’s not allow the perfect to be the enemy of good.

USDOT Roundtable on Data for Automated Vehicle Safety

On December 7th of 2017 the USDOT convened an interesting group of stakeholders to discuss automated vehicle data needs. The goal was simply to better understand what will be needed, so we can all work in that same direction. Attendees included automakers, regulators, local agencies, privacy advocates, data aggregators including Waze and HERE, universities, and industry.

They have published a short document detailing their findings. Download “roundtable-data-automated-vehicle-safety-report[3585]” here.

A set of four principles was discussed and supported by the group. Those included

  • Promote best practices for data security and privacy.
  • Act as a facilitator to promote voluntary data exchanges.
  • Start out small to find what works and then build on that.
  • Coordinate across modes to save time and money.

Number 2 is perhaps the most problematic. Vehicle and component manufacturers are still playing their cards very close to their vests. They will continue to protect whatever competitive advantage they feel they have. They don’t mind sharing what everyone else is sharing but don’t want to go beyond that point for obvious reasons. So, what will be shared will start with basics such as crash data, AV hours driven, etc. and will grow from there.

The good news, for our purposes here, is the discussion of high priority use cases. #1 on the list is “Monitoring Planned and Unplanned Work Zones”. The data they felt was of the highest value included, “Work zone locations, planned duration of project, updates, planned lane closures, changes in signing, directions, or parking.”

Other encouraging use cases include #2 “Providing Real-Time Road Conditions”. There they discuss the need for data on detours and missing or deficient signs and pavement markings.

Under testing discussions, there was an emphasis on safety-critical scenarios which would have to include work zones. Clearly manufacturers must test not just in ideal conditions, but in all conditions including bad weather, poorly delineated work zones, and in and around major and minor incidents.

They coined the term “Edge Cases” which refer to a “problem or situation that occurs only at the extreme operating parameter.” Certainly, most testing today will continue at or below 35 MPH on a sunny day and under controlled conditions. But once we are all satisfied that AVs can drive safety in ideal conditions, it will be time for the worst-case scenarios. Again, work zones will surely be a part of that.

The last use case of interest was improving roadway inventories. The group felt high-value data for this effort included,””edge-to-edge”, high-definition map elements (e.g., signs and signals, curbs, pavement markings, tolls, express lanes, bridge heights and weight capacities, highway dividers, overpasses, pedestrian areas, bicycle lanes, taxi drop-off zones, (and) quality metrics.”

Under “proposed federal roles” they talk about the USDOT acting as a facilitator of sharing and discussions between the various stakeholders. It’s good to know work zones are now a part of that discussion. Thank you to USDOT for helping make that happen. Our greatest fear just a few short years ago was that the automotive industry would get too far down the road with their development to accommodate special circumstances including work zones, special events and incident response. It’s great to see that won’t be the case.

Are Autonomous Vehicles Safe?

On February 6th we sat in on a FHWA T3 webinar entitled “Are Autonomous Vehicles Safe?” It was moderated by Dr. Francesca Favaro of San Jose State’s Mineta Transportation Institute. She runs a program known as RISA2S – “Risk & Safety Assessment of Autonomous Systems” and recently examined California DMV data from 2014 through 2016 on crashes and disengagements of automated vehicles.

Because their data is from automated vehicles on the road today, their focus has been on SAE Level 3 automation. That is, by and large, what is being tested now. Most manufacturers are not planning to offer Level 3 vehicles to the general public. But as a result their findings point out the strengths and weaknesses of Level 3 automation. So for that reason most of their presentation came to focus on disengagements – when the vehicle gives control back to the driver – and driver reaction time to those disengagements.

This is an issue of critical importance to work zones. At some point in the future autonomous vehicles will negotiate work zones without need of human input. But that is many, many years from now. In the meantime, a mixed fleet of cars and trucks with varying levels of automation will be passing through our work zones. As Paul Carlson said at the recent ATSSA Innovation Council meeting, “We have had a mixed fleet for some time now. Any discussions of a mixed fleet now are just the next iteration of that.”

So the two related issues of when AVs disengage control, and how drivers react to those disengagements will be an important point of discussion for the foreseeable future.

Their data on disengagements was very interesting. The frequency of disengagements is declining. In fact in 2016 they were one-third of what they were per mile travelled in 2014. So the technology is improving rapidly. Machine learning will continue that trend.

11% of all disengagements were due to external conditions. 49% were due to system failures of some kind. 33% were due to human factors. And 7% to “other”.

Work zones fall within external conditions. 2.22% of all disengagements were due to construction zones and 4.63% were due to poorly marked lanes. Now, we don’t know much about the conditions when and where this testing took place. Speeds were all at or below 30 MPH. But we don’t know if it was dry and sunny, or raining at night. And we don’t know if the time spent in work zones was typical of your average driver.

Chances are they were not. In fact, chances are current testing avoids work zones most of the time so disengagements in real-world work zones would likely be many times greater.

30.12% of disengagements are due to human factors – usually driver discomfort. Some of that is a trust issue with the technology. But a large part is a desire to stay safe in fast changing situations such as near incidents, work zones, or other higher volume conditions. So I think we need to include some of that data as well.

Next let’s consider driver reaction to these disengagements. This is really two issues: what the driver does, and how fast he or she does it. But the study looked only at driver reaction time. The California DMV has not yet defined what is meant by “reaction time” yet manufacturers are required to measure it. So the data presented is inconsistent in its terminology. With that in mind it is still interesting and helps point the way for future studies.

This testing was done in driving simulators. Subjects reaction times varied from 0.87 seconds to as much as 3.17 seconds. Again, that is in a simulator when the test subject was told to expect something. Other studies have shown mean reaction times of 2 seconds or more.

Let’s use the 2 second number, though it may be much higher. At 65 MPH a vehicle would travel nearly 200 feet in that time. A lot can happen in 200 feet when approaching or adjacent to a work zone. So clearly disengagements should occur in advance of the work zone giving drivers time to acclimate themselves to the situation around them. For the next 20+ years many of the vehicles passing through work zones will turn control over to the driver. So rather than try to deal with those within the confines of the work zone, lets’ just automatically turn control over to drivers before they enter it. That will provide a more predictable hand-off in a safer environment.

This study was just their first attempt. As more data is collected and as terminology becomes better defined and as testing ventures into more “real world” scenarios, we will learn much more. We look forward to future reports from RISA2S and other AV research organizations.

FHWA Request for Information Regarding Automated Driving Systems

This blog just posted a couple of days ago, but this topic can’t wait, so we are posting again today. On January 18th the Federal Register published a Request For Information from FHWA regarding automated driving systems (ADS). It asks DOT’s, manufacturers, trade associations, and other interested parties for their answers to questions in ten specific areas.  Download Docket FHWA-2017-0049. All comments must be received by March 5th, so please get started.

The work zone ITS world should be most interested in questions 4, 5, 9 and 10. You will also be interested in many of the other questions if you are involved in static signs, pavement marking or other permanent roadway safety infrastructure.

First, let’s commend the FHWA for asking these questions. It wasn’t long ago that we worried that automakers and regulating agencies did not know what they did not know. A great deal of time and effort has gone into building coalitions with these folks and it appears that is beginning to pay off.

So lets’ reward their curiosity with well written and timely responses. You can do so individually and/or through your industry associations such as the American Traffic Safety Services Association.

We will start the ball rolling now with these suggested responses to the four questions mentioned earlier. These are short in the interest of time, but should be fleshed out in any formal response.

Question 4: How should FHWA engage with industry and automation technology developers to understand potential infrastructure requirements?

Include work zone ITS providers and trade associations like ATSSA in the conversation. Many of us are already participating in AV events including the Automated Vehicles Symposium, the ITS World Congress, etc. Presentations at these events focused on work zones have lead to many productive conversations and several “ah-ha” moments for AV manufacturers. Please encourage more of this going forward.

Question 5: What is the role of digital infrastructure and data in enabling needed information exchange between ADS and roadside infrastructure?

Work zones will be the most common anomaly in digital maps unless we begin preparing now. Arrow boards, flagger stations, and other active work zones can be equipped to report their location and other pertinent information automatically and in real time. The same could be done for emergency responders and special events. Only by doing so can we hope to prevent crashes like the one reported January 23rd  ( Mercury News ). Safety is the driving force behind this initiative, but it will also reduce drive times, reduce air pollution, and improve the efficiency of our road networks.

Question 9: What variable information or data would ADS benefit from obtaining and how should that data be best obtained?

Work zones are the single most frequent cause of non-recurring congestion. Clearly real-time work zone data should be included. This data must include the precise location of the work zone, when and where lanes are closed and when they are opened up again, where flagging operations are taking place, and any other important features of the traffic control including lane splits, narrow lanes, crossovers, and full closures and detours. Finally delay times should also be included whenever available.

Question 10: What issues do road owners and operators need to consider in terms of infrastructure modifications and traffic operations as they encounter a mixed vehicle fleet during the transition period to a potentially fully automated fleet?

It is estimated that it will take at least 20 years to reach a point where the vast majority of vehicles are highly automated. Until then work zones will be just as dangerous for conventional vehicles as they are now. Don’t scrimp on traffic control devices, signage or pavement markings in the hopes that they won’t be needed.

As for those automated vehicles, most will not be capable of navigating autonomously though an active work zone. Plan to trigger the vehicles to hand over control to the driver well in advance of the work zone. Studies show drivers need a minimum of 8 to 10 seconds to regain situational awareness.

Work zones, incident response, and special events will test these systems more than anything else. Make them a big part of the conversation now to avoid problems in the not too distant future!

5G Cell Service and Opportunities for Our Industry

By now, most of you are aware that 5G phone service will be here soon. But you may not understand what that means for our industry. An article written by Hongtao Zhan of SureCall and published recently in VB talks about its potential:

https://venturebeat.com/2017/09/30/5g-isnt-just-faster-it-will-open-up-a-whole-new-world/

As the article points out, download speeds could be as much as 100 times faster than we currently experience with 4G service. This service will be expensive at first but once everyone has switched to 5G devices those faster download speeds could result in greater use of video as data rates eventually decline.

But the most important aspect of 5G for our purposes is latency. Latency is a measure of how quickly critical data is transmitted. 5G offers near zero latency. This will enable an incredible array of new technologies affecting every part of our lives. That is why “Qualcomm is calling 5G the “platform for invention.””

Mr. Zhan describes ways 5G could be used for things like haptic controls in vehicles for purposes such as lane keeping, collision avoidance and more. For our world haptic controls mean we could deploy “virtual rumble strips” in advance of work areas to wake up drivers and perhaps even to return control of autonomous vehicles over to drivers.

Zero latency means workers could be removed from the work area and could perform many dangerous operations remotely using a virtual reality head set and controls. For example, they could “drive” TMA trucks remotely. We might also create a remote control cone setting machine. Striping trucks and RPM installation might also be automated.

How about a phone app to warn workers? With near zero latency, we could create an intrusion warning system that works fast enough to save lives, while requiring very little in additional equipment – just the smart phones everyone is already carrying around. The work area could be delineated on a digital map and any vehicle crossing those lines would trigger warnings to anyone in the area who has downloaded the app.

The possibilities are endless and this new communications protocol is right around the corner. It is time for us to begin thinking about how we might use it to improve safety and save lives.

Work Zone Reporting to Autonomous Vehicles

We just returned from ATSSA’s Midyear meetings in Louisville, Kentucky. The Innovation Council meeting was well attended and included several very interesting speakers. Many topics were discussed but the real focus of these discussions, both during and after the meeting, was autonomous and automated vehicles and how our members can best prepare for them.

Speakers including Dr. Paul Carlson talked about the importance of signs and pavement markings bright enough to be seen and recognized by automated vehicles. AV manufacturers have stated that this is the most important thing we as an industry can do to prepare, at least from the autonomous vehicle perspective.

But from a stakeholders’ perspective – specifically work zone safety – many wonder how autonomous vehicles will know where work zones are located and what they will encounter as they drive through them. This blog has discussed this subject several times over the past few weeks, but given the interest in Louisville, it seemed a good time to review all of the likely ways in which this will be accomplished and consider the advantages and disadvantages of each.

There are at least 6 ways to do this. And by “this” we mean update digital maps in real time. First we must tell everyone where work zones are active. That’s the most important part. For by telling them, those autonomous vehicles can then trigger a return of control to the driver well before the vehicle enters the actual work zone. But ideally, these systems will also include information about that work zone including which lanes are closed, prevailing speeds, and geometric changes including lane shifts, narrow lanes, etc.

So, in no particular order, these are the more likely ways of getting that information out in real time:

Traffic Control Device Automated Reporting

Devices including arrow boards, traffic sensors, flashing beacons, and stop/slow paddles can be equipped to report to a traffic data service or DOT website. This is already being done today. When the device is turned on, it reports its GPS coordinates and the type of work zone. For example, an arrow board, when turned on would report a lane closure. When it is turned off, the device reports the work zone is no longer active.

The advantage of this approach is the activity is truly reported in real time without human input. Another advantage is the location will change as the equipment moves, say for a paving or crack sealing operation. The disadvantage is the need to replace older devices with newer devices that include this feature.

3M Two-Dimensional Bar Codes

This was the subject of a post on August 21st and was discussed by Chuck Bergman of Michigan DOT and Eric Hedman of 3M at the Innovation Council meeting. 3M has installed signs on I-75 in Michigan with two-dimensional bar codes embedded in their sign sheeting. A driver might see a sign saying ROAD WORK AHEAD but infrared cameras in the car would see a second embedded message telling the car to relinquish control to the driver, or to reduce speed automatically to 45 MPH, or any one of a number of other possibilities.

This approach will work well for longer term work zones and ones where the desired message is unlikely to change often. It will likely be low cost and could act as a fail-safe warning to autonomous vehicles. It does not update digital maps simply by installing the signs, but we assume that will be done manually at about the same time.

State DOT Work Zone Phone Apps

Many states require contractors to request lane closures in advance and then to report when those closures begin and end. Some now accomplish this through smart phone apps that make it quick and easy o report in real time.

This is already taking place but it does require someone to key in the closure when it begins and ends. And moving operations won’t be precisely geo-located. Still, it is inexpensive and requires very little effort.

Waze, HERE and other Crowd Sourced Traffic Apps

Users of these smart phone apps can note active work zones and other issues affecting traffic and that information is shared with all other users. This additional information is helpful but depends on users to remain current. Interestingly these apps are beginning to include data streams from work zone ITS systems. So the hybridization of these systems has already begun. And in our last post we noted that Caltrans traffic website known as QuickMap now includes Waze work zone data.

I2V (Infrastructure to Vehicle) Reporting via 4G/5G or DSRC

This was how we originally envisioned the process taking place. A radio of some sort might be installed in advance warning message signs or arrow boards where it would broadcast to approaching traffic to warn of upcoming work zones. These devices might also report slow or stopped traffic ahead. This may still happen, but advances in V2V (vehicle to vehicle) communications both 5G and DSRC make this less likely.

Automatic Reporting by Autonomous Vehicles

AV data collection will “see” and take note of variations of the real world roads from the digital map. This might include some standard deployment of devices in advance of work zones that could be recognized by algorithms to mean a work zone lies ahead.

This has not been suggested that we know of, but autonomous vehicles collect data continuously. That’s a lot of data. Machine learning and sophisticated algorithms will, in time, learn to recognize work zones. Logically those will then be reported automatically as work zones change. This may not occur for many years but it will happen automatically one day.

The change from driven to autonomous vehicles will be a very gradual one. Most experts believe it will take at least 25 years and even then older vehicles, collector cars, etc. will still be sharing the road with driverless ones. Furthermore, the choice of technology to warn of work zones will vary with location, construction activity, project duration, and more. As a result, differing combinations of technologies will likely be used in an effort to reach the greatest number of vehicles and to provide redundancy. After all, as time has proven over and over again, as cars become easier to drive, we become worse drivers. So it will be all the more important that we warn drivers and vehicles of work zones ahead.

Caltrans QuickMap to Add Waze Data

 

Caltrans recently announced changes to their popular QuickMap travel app. The app is available online at http://quickmap.dot.ca.gov/ and from your app store for both Apple and Android. In QuickMap users choose what they want to see, and the area they are interested in seeing, and a custom map shows them exactly that and no more. Travel times and factors affecting travel times such as work zones, weather and other incidents are all displayed in near real time.

They have now added an option to see Waze data. This is significant to those of us interested in work zone ITS because Waze displays iCone sensor data as work zone locations. For example, Road-Tech currently has an iCone system on SR99 in Fresno and the work zone is displayed in QuickMap with an icon of a worker in a hard hat:

Eventually these icons when clicked on will display detailed travel speeds and other pertinent information. That data will help drivers avoid delays and better plan their routes. And in Waze, drivers can add their own information on work zones, crashes and other incidents.

QuickMap is testing the next mobile version in which users can input their own Waze markers directly from QuickMap. It will be one more way to get real-time work zone information to the people that need it most!