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Startup Proposal: Intelligent Traffic Signals

J. Donald Tillman
May 18, 2015
Updated Nov 23, 2015

traffic light

Traffic signals have always been run by timers set up by traffic engineering professionals. They can be independent units, possibly with pattern branches triggered by pedestrian requests or lane sensors, or a number of units all under central computer control. And we've all been stuck in frustrating traffic situations where the signals just happened to go the worst possible ways at the worst possible times.

What if traffic signals were networked intelligent devices with iPhone-like microprocessor systems, sensors, and communications links? What if they were able to continuously adjust and optimize their timings for the most efficient possible traffic flow all on their own? What if they could replace the monitoring and controlling functions of municipal traffic control centers?

More efficient travel with less traffic congestion could likely save billions of gallons of gasoline and tens of millions of tons of exhaust emissions each year in the US alone. Less road construction would be needed as existing roads are used more efficiently.

The possibilities are enormous:

A municipality could purchase smart traffic signals over time on a replacement basis, similar to the switch to LED traffic lights. Each new traffic signal will improve the performance of nearby smart traffic signals so there is an incentive to add more.

There are at least 300,000 signaled intersections in the US. International sales would be substantial. Cities and counties are accustomed to spending $50,000 to $500,000 to purchase and install a traffic signal. All sorts of services would be available by subscription (statistical analysis, traffic control tools, algorithm libraries, etc.). Annual revenues would be billions of dollars in direct sales alone. This could be an enormous business that has a profoundly positive effect on the environment.

I'm not seeing evidence of anybody currently doing anything like this. There is a new development in traffic signals called "Adaptive Traffic Control" (DOT: Adaptive Signal Control Technology), but all implementations so far seem to be major projects involving a central computer system. There are some experiments in the references below, certainly, but I don't see any patents, or solid progress, or any in use, or anybody approaching it the way I've described here.

Note that the city of Los Angeles recently finished a $400 million project to connect all 4500 of their controlled intersections, with video and sensor data, to a central computer facility staffed with traffic engineers. (NY Times: To Fight Gridlock, Los Angeles Synchronizes Every Red Light)

This would be a major project and would probably require a staff of over 100 including experts in multiple areas (electrical engineering, software engineering, simulation, artificial intelligence, civil engineering, traffic engineers, etc.) and venture funding of around $100 million. The market, world wide, seems to be somewhere around $50 billion.

Some References:

Zubillaga, et al: Measuring the Complexity of Self-Organizing Traffic Lights

Berman: How AI Turns Traffic Lights Into Intelligent Agents

Chavan: Design of Intelligent Traffic Light Controller Using Embedded System

Carnegie Mellon University: Smart Traffic Signals

Carnegie Mellon University: Smart Signals — Pilot Study on Traffic Lights Reduces Pollution, Traffic Clogs

US Department of Transportation: Manual on Uniform Traffic Control Devices

Phys.org: Smarter programming of stoplights could improve efficiency of urban traffic

BBC: How smart traffic signals may ease your commute

NY Times: Choreographing the Dance of Traffic Lights

Ghena, et al: Green Lights Forever: Analyzing the Security of Traffic Infrastructure

Boston Transportation Department: The Benefits of Retiming/Rephasing Traffic Signals in the Back Bay

Copyright 2015, J. Donald Tillman
Email: don -at- till.com
Web page: http://www.till.com