Tech Report Number


Sponsoring Organization

Indiana Local Technical Assistance Program

Performing Organization

Purdue University School of Civil Engineering

Date of this Version



traffic signal, adaptive traffic signal control, adaptive control systems, performance measures, link-pivot algorithm


The project focused on accelerating implementation of research recommendations emerging from traffic signal research projects conducted by the National Cooperative Research Program and Indiana Department of Transportation. This project developed specification language that was subsequently used in procurements in Elkhart County, IN; Lafayette, IN; and Morgantown, WV. The performance measures specified in Appendix A and subsequently deployed in Elkhart County, IN, and Lafayette, IN, were the first commercial deployment of real-time traffic signal performance measures recommended by NCHRP 3-79a. The deployment in Lafayette, IN, received an ACEC award in March 2012. In addition to accelerating implementation, this research project examined the feasibility of deploying adaptive traffic signal control in the near term (next 12-18 months). The authors of this report believe the detection requirements and the level of engineering staff support required to operate the current generation of adaptive control systems do not warrant implementation without careful assessment of detector placement, detection quality, and a commitment by the agency for substantial recurring engineering support to operate those systems. Instead, the authors recommend pursuing a hybrid approach of scheduled review of traffic signal performance measures to identify performance improvement opportunities and the use of the link-pivot algorithm developed by Purdue.