Traffic Signal Detection and Bicycles

I answered a question on the APBP listserv and thought I should capture it and update it as we learn more about the technology.

The XX State Highway Administration is telling my hometown that updates to signal hardware, namely, video detection technology, will be able to detect bicyclists where loop detectors are installed currently, and not doing a great job. I’ve noticed in practice that it seems to work, but I wonder about night time and positioning sensitivity, etc. What’s the experience out there with video detection for bikes?

Also, they rejected out of hand the use of a bike push button actuator installed at the right curb edge as not permitted based on the XX version of the MUTCD. I thought I recall Portland and other jurisdictions had installed bike actuators on the curb.

Well, since he called Portland out and I am that guy in Portland, I felt obliged to spend the lunch hour pounding this out.....

Video detection is better than you might think and I have never heard of a ban on push buttons, but I wouldn't encourage their use either because of the potential for them to get hit if they are close to the curb. We sent an intern out to answer your question a few years ago and the informal, limited sample size, nonscientific results are posted here. The bottom line for traffic design is we can and should do better at traffic signals. For those on the listserv that want details, keep reading... 

The City of Portland has studied several different types of detectors at a few select locations. Often, we have a unique problem we're trying to solve. 

Our standard for detecting people on bicycles is the same as it is for motor vehicles, the gold standard of inductive loop detection. We have used this for a long time and the technology is proven. The use of inductive loops requires the agency ask the field technicians to set the sensitivities high enough to identify bikes. Yet, it does require people on bikes to be over the loops and they are problematic for detecting people on bikes (as a designer) because you have to know where a person on a bicycle will be. We use stencils on the pavement to help give an indication of where a bicycle should be placed to be detected, but this doesn't work so well in snow, when leafs are on the pavement, etc. Bottom line, all detection has some challenges and inductive loops are no exception. One thing we have tried to improve is to provide positive feedback to someone that they have been detected. To accomplish this, we have implemented a detector confirmation light to give an indication that they have been detected. Some information about that is found at the following link.

The City hasn't used video traditionally because of expense and problems with fog, false calls, etc that were originally documented in this research by Purdue University . That hasn't stopped many agencies from widespread adoption of video as their standard, but it did lead to the Indiana DOT eliminating the use of video detection. Now, this research is from 2006 and the technology has improved a lot, but we still use inductive loops in most cases in Portland. Let me say it again, video detection has improved. Our recent study (not really research) showed that video detection worked better than we anticipated (nearly 100%) with good lighting conditions at the intersection and no fog. We watched some video during different times of day including periods of darkness where we thought we would see significant problems and it was better than we anticipated for detecting people on bicycles. This study did a one to one comparison with microwave detection, which we thought would be better because of the properties associated with it as a technology and it was similar in terms of performance. The link has some numbers, but it is not a definitive study. The National Cooperative Highway Research Program 7-19 is going to study this further. 

A nearby agency that uses video detection for most of their applications has decided to stop using it because of the increased maintenance associated with problems reported by people about the detection failing in the on condition (basically side streets getting green time when there is no traffic), which is one of the problems that Purdue University found in their original research. 

Our next step is to study a thermal imaging camera because we are interested in the reduced maintenance potential associated with not having to clean the lens and the ability to distinguish between cars and people on bikes. We just installed it a few weeks ago and have some initial concerns, but nothing yet in terms of a study to share. 

We also have a location where we are going to put the new Sensys bike detection product to use because that system is wireless from the in ground unit to the traffic signal controller, so it may reduce our costs. We're not sure how well that will work, but we're going to study it. 

To answer your original question, the position sensitivity is a big part of making any detection work. Video and microwave are both more flexible in terms of the field implementation obviously. Our technicians care about people on bicycles and they have worked to make the technology work, it is not something that is particularly easy to setup. 

Sorry for the long response, this is clearly an area where more research is necessary. 

Green Wave for Bicycles: Findings from a Case Study in Portland, Oregon

Abstract for a new paper we're working on with Portland State University...
Over the past decade, there has been a significant increase in the proportion of active modes of transportation especially in urban areas. The benefits of these active transportation modes are well recognized: lower congestion and emission levels and advances in personal health. While there have been infrastructure improvements to cater to the growing demands of non-motorized transportation, efforts to optimize system operations for bicyclists and pedestrians have been lagging. The purpose of signal timing at intersections is to move traffic in a safe and efficient manner consistent with the policies of the local jurisdiction. In many communities, signal timing and coordination accord priority to automobile movements while other users of the transportation system are often ignored. With the goal of moving toward a 25% cycling mode split by 2030, the City of Portland has chosen to optimize signal timing operation to prioritize the needs of people on bicycle on select corridors.

This paper reports on the development of a signal timing plan for a busy bicycle commuter corridor in Portland, Oregon. The objective of the signal timing design was to provide a green wave for people on bicycles. Setting traffic signal timing to progress bicycle traffic can minimize stops, lead to platooning of bicycles, and potentially attract cyclists to the facility resulting in the safety in numbers phenomenon. The North Vancouver and North Williams corridor one way couplet in Portland, Oregon is a heavily traveled bicycle commuter route with over 3,000 bicyclists per day. In order to develop signal timing for the 13 signals on the couplet, bicycle and auto travel times and speeds were collected using GPS devices. The traffic signal timing optimization software Synchro was used to generate signal timing that allowed separate bicycle and auto coordinated progression. Post implementation, travel time and speed data was collected
to evaluate the new signal timing. Preliminary analysis indicates an average decrease of 36% in vehicle stops and 41% in bicycle stops per progressed platoon on the couplet.  The poster will report on our findings and lessons learned.

Left Turn Queue Box Parallel to Streetcar Tracks in The Netherlands

 One of the innovations that Portland has implemented from the Dutch experience is left turn queue boxes. The following is an example of one such effort where the bicycle lane has the elephant's feet marking and the vehicle minor street movement and the bicycle left turn movement. The reason for this treatment was that the bike lane was parallel to streetcar tracks. We came across this intersection on the way back from the beach at Monster a town in South Holland.

Glad Rooster Sign

There were a couple of traffic signs from my visit to the Netherlands that provided some levity during our tours around the country. This is one of my favorites. I think the translation of "glad rooster" is smooth grid, which in this case seemed to be the same as a cattle guard for us in the U.S. Perhaps someone that is Dutch will see this and  chime in on what this means.

I was also surprised that the sign was on the left hand side of the path.

Signal IntersectionDesign: Bicycle Lane & Left Side Mixing Zone on 1st Ave

This person chose to weave through the left turning traffic to the left, so as
to avoid the conflict. The next vehicle is in queue, so this is a relatively
safe movement, as long as someone doesn't pull from the adjacent through
lane into the parking on the farside. In the next picture, you can see a
concrete barrier that protects against that.  

This person passes the vehicle on the right and then moves back into
the marked area. This picture also shows the bus on the right hand side
they have a bus priority lane in red on the right hand side of the street. 

   The mixing zone in NYC was something that I had wanted to spend some time looking at because when I first thought of the idea, I didn't know how well it would work. My past visit to NYC suggested that it was something so new that they weren't sure how it would work, but they did know that it eliminated the need for a bicycle signal movement that is separated in time from the left turning traffic, essentially providing a permissive left across the bicycle lane, which requires motorists to look back before making the left turn to see if a person on a bicycle is approaching.
Generally, it was a new concept to me and upon visiting this location, I was curious to see how folks were using the intersection.

The NY Times did a Q&A about the lanes and the engineer from NYC offered the following:  “this ‘complete street’ treatment has been shown to decrease injuries by up to 58 percent for everyone using these streets, whether on foot, on a bike or in a vehicle.”

The second question on the Q&A is about traffic signal timing, which is a bonus for those that clink on the link. 

A little more research shows that the NYCDOT did some initial work on this back in 2009 as covered by StreetFilms. NE Multnomah Boulevard is Portland's first foray into mixing zones and it includes buses and that should something that the City studies with one of its summer interns. 

Innovations at Traffic Signals for Cycling: Would a Thermal Imaging Camera Improve Detection

The first person detected by the thermal imaging camera in Portland. 

I presented on the topic "Innovations at Traffic Signals for Cycling" at the most recent meeting of the Oregon Section of the Institute of Transportation Engineers. There were a few new things we had done in the past year that I felt compelled to share information about. The most recent was a Thermal Imaging Sensor. Before I go into detail on that, let's review some of the recent innovations we have implemented in the past year.
In June, we repurposed our school zone enforcement light as a bike detected confirmation light. We have installed these at two locations and the response from their use has been very positive from the user community.  One of the reminders from the meeting was something that Rick Nys, the Clackamas County Traffic Engineer mentioned. He highlighted that the County used feedback from BikePortland.org to guide their improvements of the first bicycle signal in their system. He also mentioned that the response from the bicycling community was so positive that "it makes them want to do more of these types of projects".

The other innovations that I described included the Dutch Bicycle Countdown to Green signal I have described before, but haven't found a way to bring to the U.S.



The newest innovation that we're studying is the use of a thermal imaging camera made by Flir/Traficon. Traficon was recently purchased by Flir and it is interesting to consider a company like this getting into the traffic business.

Flir cameras come from military applications

 That hasn't always worked so well for other companies, but I am hopeful that they will be in it for the long haul. The good news with this situation is that there is an existing expertise with Traficon which is a Belgian company. The company representatives that we met with during the install of this unit suggests that we should be able to do what we want to detect bikes and distinguish their heat signature from that of a car. We'll study the equipment similar to what we did with the microwave and video detection at the Broadway Bridge NW Lovejoy intersection.

Here's a summary of the presentation in pictures.

The location of the test is SE Cesar E Chavez and Lincoln, a popular
bike route that is busy during the commute periods. 

I mentioned it was busy, this was after the morning peak and
people on bikes outnumbered vehicles even on a rainy day.

The push button here is mounted so the person on a bike
can reach it, but it isn't easy. The other direction is impossible to
activate from the street.

A peek in the cabinet of the equipment, the display was temporary,
but we do have access to the images back in the Traffic Operations Center.

I am looking forward to having this studied and learning a bit more about future applications.

Signal Timing Manual, 2nd Edition

NCHRP documents are influential in the
transportation industry and guide practice. 

I am reviewing a draft of the 2nd Edition of the Signal Timing Manual. One of my roles working for the City has been to review work more as opposed to produce it and this is just another example of this. This is especially true with the rewrite of the Signal Timing Manual. I am Chair of the panel that is providing a reivew of the draft documents and will serve to insure that the National Cooperative Highway Research Program (NCHRP) is of sufficient quality to put the Transportation Research Board stamp on the document. I am aware of several NCHRP projects that were never completed, so it is an important role to make sure that there is consensus and that the document reflects practice that would improve the conditions of traffic signals. The current project is titled NCHRP 3-103.

Of course, the First Edition of the Signal Timing Manual is a sterling example of a document that is one that has helped engineers, especially those that are unfamiliar with the details, to decipher practice that they may not be aware of. one of the issues associated with the Manual that was new to the field was the connection of traffic signals to regional policies. Chapter 2, specifically Section 2.1 highlights the importance of this and seeks to guide the engineer toward meaningful observance of the community's goals as opposed to those that are determined based on their own personal bias. In linking the engineer to the community's stated priorities, I believe the engineer takes a more important role in the organization and is able to focus on the implementation as opposed to defending themselves or their work.

The National Cooperative Highway Research Program is very influential in transportation engineering practice. It is important that multimodal considerations be taken when developing the guidelines. An example of one of the comments I had is shown below. It is a section on traffic signal detector design. The authors identified bicycle signals as a possible solution earlier in the chapter which was good to influencing that portion of the practice, but what's even more common than a bicycle stencil in a signal is the provision of detection for people on bicycles. In my previous blog post about the signal at N Winning Way and N Williams, the addition of an advance detector in the bike lane has reduced the delay for people on bikes by providing a little additional time for people on this approach, so that it is less likely they are skipped by the other movements at the traffic signal.

View Larger Map

An example of my comments for the signal detection portion of Chapter 4. 

Resume Updated 2013

PETER  KOONCE, PE

Professional Civil Engineer Licensed in Oregon and via the National Council of Examiners for Engineering and Surveying

EDUCATION

MS Civil Engineering, Texas A&M University, College Station, TX, 1998

BS Civil Engineering, Oregon State University, Corvallis, OR, 1995

WORK EXPERIENCE

City of Portland, Bureau of Transportation, Signals, Street Lighting, & ITS Division Manager, November 2009-current

Manages the design, operations, and maintenance of the City’s traffic signals, street lighting, and ITS network. The position includes responsibility for 48 staff and a budget of $15 Million annually.

Kittelson & Associates, Inc., Principal Engineer, Portland, OR, 1998-2009

Participated in a variety of traffic operations, transportation planning, and transit operations projects across the United States and Canada, providing clients with a well-rounded perspective based on a diversity of expertise. Recognized leader in transit and signal systems specific issues, helping agencies plan traffic signal system and ITS improvements to make more sustainable communities. He is currently managing over $2M of consultant work activity and as many as 10 staff in Kittelson offices across the country. Managed the City of Portland’s Transit Signal Priority project (1999-2003), a $6M effort to upgrade over 250 traffic signals and the entire TriMet bus fleet (this project earned a Grand Award from the American Council of Engineering Consultants in 2003).

Portland State University, Adjunct Professor, 2002- current

Teaches a Summer Course in Transportation related to traffic signal timing and engineering applications and serves as an advisor to the PORTAL program, the regional data archive system at PSU.Developed PSU's first Civil Engineering Study Abroad program in partnership with the Northeastern University program at the Technical University Delft, The Netherlands. 

Texas Transportation Institute, Graduate Research Assistant, 1997-1998

Kittelson & Associates, Inc., Transportation Analyst, Portland, OR, 1995-1997

TriMet, Intern, Portland, OR, 1994

RELEVANT VOLUNTEER POSITIONS

Llewellyn Elementary School Foundation, Portland Public Schools, President, 2009

Accepted role as president for the Foundation to serve as organizer amongst the parents for supporting the academic programs focused on arts and music. Hosted activities ranging from a Remodeled Home Tour to Auction fundraisers.

Portland Bicycle Master Plan, Design Subcommittee, 2008-2009

Served as a technical representative throughout the past several months as the City worked on updating the Bicycle Master Plan. Activities included discussing policies with City staff about new traffic engineering applications and developing technical briefs for the Plan.

City of Milwaukie Budget Committee Member 2001-2005

Provided review of the City’s $35M annual budget as one of the 5-person citizen Committee that worked directly with the City Council and its City Manager. Reviewed work plans of every City department including Police, Public Works, etc asking questions related to the annual changes in capital programs and the asset management program the City employed.

Ardenwald-Johnson Creek Neighborhood Association Chair 2000-2002

Served as Chair of the Neighborhood Association and applied for and managed grants for community events as diverse as neighborhood clean up days to concerts in the park. Worked with City leaders during the review of the Metro South Corridor planning process when the Portland to Milwaukie line was being reconsidered following the success of the Interstate MAX line. Was the primary author of the 14 points that lead neighborhood rail.

AFFILIATIONS

Transportation Research Board (TRB)
Traffic Signal Systems Committee, Chair 2012-current, Secretary 2009-2012
Bus Transit Systems Committee, Member 2005-2011

Institute of Transportation Engineers, multiple positions, currently serving on the Sustainiblity Task Force and the Public Agency Council. Currently serving as Past President of the Oregon Section.

Bicycle Transportation Alliance, Oregon Walks Member

APPOINTMENTS

National Cooperative Highway Research Program, Project 3-103 Update to the Traffic Signal Timing Manual, Panel Chair

National Bus Rapid Transit Institute, University of South Florida, Peer Review Panel

Initiative for Bicycle and Pedestrian Innovation, Strategic Planning Task Force

National Institute for Advanced Transportation Technology, Advisory Board

AWARDS

Outstanding Early Career, Oregon State University, 2009

Distinguished Young Professional Award, ITE Western District, 2007

Outstanding Service Award, Awarded by Oregon Section Student Chapter, 2001

Exceptional Student Award, Southwest University Transportation Center, 1998

SELECTED PRESENTATIONS AND PUBLICATIONS (additional available upon request)

Koonce, Peter, "Portland's Designing for 8 to 80", Presentation at the Transportation Research Board Workshop on Innovative Pedestrian and Bicycle Accomodations at Roundabouts New Ideas and Surpassing Barriers to Innovation, January 14, 2013. 

Koonce, Peter, "Prioritizing Transit in a Connected Vehicle World", ITE Journal, December 2012.

Thompson, S.R., C. Monsere, M. Figliozzi, P. Koonce, and G. Obery, "Bicycle-Specific Traffic Signals: Results from a State-of-the-Practice Review", selected for publication as part of 2013 Transportation Research Board Annual Meeting, http://www.its.pdx.edu/upload_docs/1354724032.pdf.

Kothuri, S., Reynolds, T., Monsere, C. and P. Koonce. Testing Strategies to Reduce Pedestrian Delay at Signalized Intersections: A Pilot Study in Portland, Oregon, Proceedings of the 92nd Annual Meeting of the Transportation Research Board,  Transportation Research Board of the National Academies, Washington DC, 2013.
Koonce, Peter, "Confessions of a Traffic Engineer: the Misuse of Level of Service and its Impact on Active Transportation", Presentation at the University of Oregon, October 12, 2012. 

Kothuri, S., Reynolds, T., Monsere, C. and P. Koonce. Preliminary Development of Methods to Automatically Collect Pedestrian Counts and Bicycle Delay at Signalized Intersections.  Proceedings of the 91st Annual Meeting of the Transportation Research Board,  Transportation Research Board of the National Academies, Washington DC, 2012.

Koonce, Peter, "Improving Pedestrian Safety with Enhanced Treatments", Presentation to the Women in Transportation Seminar, Portland Chapter, May 10, 2012.

Koonce, Peter, "Priority for Trucks at Traffic Signals: Project Examples in Portland", Presentation to the Portland Freight Committee, February 3, 2011.

Koonce, Peter, "Bicycle Signals 2.0", Presentation at the Transportation Research Board Annual Meeting Workshop on the National Association of City Transportation Officials, January 22, 2011

Koonce, Peter, “Remaking Traffic Signals in Support of Sustainability: Policy Based Transportation Operations”, Presentation at the Portland Chapter of the Women’s Transportation Seminar, Portland, OR, November 9, 2010.

Koonce, Peter, “Reduction of Environmental Load by Signal Control Improvement: Experience from the USA”, Presentation at the Annual Meeting of UTMS Japan, Tokyo, Japan, September 30, 2010

Koonce, Peter, “Transportation Engineering Applications: A Course for Future Practitioners with a Focus on Signal Timing and Multimodal Policies”, Presentation at the Transportation Research Board Committee on Traffic Signals Systems Summer Meeting, Moscow, Idaho, July 19, 2010.

Koonce, Peter, “Sustainable Transportation System Management: Innovative Concepts, Projects, and Partnerships”, Presentation at ITS America Annual Meeting, Houston, Texas, May 4, 2010

Koonce, Peter, “Transportation Operations Efforts to Reduce GHG”, Webinar presentation for AASHTO Transportation and Climate Change Resource Center, posted online: http://environment.transportation.org/center/products_programs/climate_change_webinars.aspx#04,  April 19, 2010

Koonce, Peter “Improving Traffic Signal Timing” Webinar Series for Institute of Transportation Engineers, 2009

Koonce, Peter, “Technology Evolution in Transit Signal Priority Applications”, Presentation at APTA Bus Rapid Transit Conference, Seattle, WA, May 5, 2009

Koonce, Peter, “An Overview of the FHWA Traffic Signal Timing Manual”, Presentation at the Institute of Transportation Engineers Spring Conference Meeting, Phoenix, AZ, March 23, 2009.

Koonce, Peter, etal, “Traffic Signal Timing Manual”, FHWA-HOP-08-02,  Federal Highway Administration, Washington, D.C. June 2008

Koonce, Peter, Lindstrom, Eric, Urbanik, Tom, Beaird, Scott. Improving the Application of Transit Signal Priority Using the NTCIP 1211 Standard. ITE Journal, Volume 78, Issue 4, pp 28-31, April 2008.

Yue Li, Peter Koonce, Meng Li, Kun Zhou, Yuwei Li, Scott Beaird, Wei-Bin Zhang, Larry Hegen, Kang Hu, Alex Skabardonis, and Z. Sonja Sun  “Transit Signal Priority Research Tools”, http://www.dot.ca.gov/newtech/researchreports/reports/2008/tsp_research_tools_final_report.pdf, Federal Transit Administration, May 2008.

Koonce, Peter, “Pedestrian Challenges to Traffic Engineers and How They Affect Traffic Signal Operations”, Presentation at the 87th Annual Meeting of the Transportation Research Board, Washington, DC, January 15, 2008.

Koonce, Peter, “Signal Timing Policies and Practices”, Presentation and Paper in the Compendium of Papers for the Institute of Transportation Engineers Annual Meeting, Pittsburgh, PA August 5-8, 2007.

Koonce, Peter, “An Overview of the FHWA Traffic Signal Timing Manual”, Presentation and Paper in the Compendium of Papers for the Institute of Transportation Engineers Western District Meeting, Portland, Oregon, July 15-18, 2007.

Burchfield, Rob, Peter Koonce, and Kevin Lee, “Improving Red Light Running Camera Site Selection”, Presentation at the Institute of Transportation Engineers Western District Meeting, Portland, Oregon, July 15-18, 2007.

Wolfe, Michael, Christopher Monsere, Peter Koonce, and Robert L. Bertini, “Improving Arterial Performance Measurement Using Traffic Signal System Data”, Submitted to the 2007 IEEE Arterial Conference.

Koonce, Peter, Paul Ryus, David Zagel, Young Park, and Jamie Parks, “An Evaluation of Comprehensive Transit Improvements—TriMet’s Streamline Program”, Journal of Public Transportation, Volume 9, No. 3, 2006.

Koonce, Peter, “Performance Measures in Traffic Signal Systems – A Practitoner’s Perspective”, Presentation at the TRB Sunday Workshop, Washington, DC, January 2006.

Koonce, Peter “Using Standards for Signal Priority”, APTA/FTA ITS Standards Workshop, Orlando, FL, January 2005.

Byrne, Neil, Peter Koonce, Rob Bertini, Chris Panglianan, Matt Lasky, “Using Hardware-in-the-Loop Simulation to Evaluate Signal Control Strategies for Transit Signal Priority”, Paper presented to the 86th Annual Meeting of the Transportation Research Board, January 2005.

Kittelson, Wayne, Peter Koonce, Sonia Hennum, Sagar Onta, and Tim Luttrell, “Volume V: Traffic Analysis Toolbox Case Studies – Benefits and Applications”, Federal Highway Administration, November 2004.

Koonce, Peter, “Traffic Operations for Bus Rapid Transit”, Presentation at the APTA/FTA/ITE BRT Symposium in Orlando, FL, October 2004.

Koonce, Peter, “Importance of Bus Stop Location on Signal Priority”, Presentation at the ITE District 6 Meeting in Sacramento, CA, June 2004

Ringert, John, Peter Koonce, Karen Giese, and Scott Beaird “Portland Transit Signal Priority Technical Report”, Kittelson & Associates, Inc., Portland, Oregon, http://www.webs1.uidaho.edu/ce574f09/resources/Portland%20Transit%20Signal%20Priority%20Report.pdf, visited February 1, 2011, originally published January 2003

REFERENCES (available upon request)