Which three agencies collaborated to develop the 170 controller?

The development of the 170 traffic signal controller was a collaborative effort primarily involving California DOT, the City of Los Angeles, and the New York State DOT. This partnership was crucial because it brought together diverse knowledge and expertise from different regions, ensuring that the controller would meet the varying needs of urban and suburban traffic management across states.

The City of Los Angeles played a significant role in the real-world application of the technology, providing insights into the complexities of traffic patterns in a major urban center. California DOT contributed extensive experience with traffic signal technology and infrastructure, allowing for the integration of advanced features that are essential for modern traffic systems. Meanwhile, the New York State DOT provided a different regional perspective, helping to refine the controller for various conditions faced in both urban and rural settings.

This collaboration was vital to maximize the functionality and effectiveness of the 170 controller, making it a widely accepted standard in traffic signal management across the United States.