Motorists will see new, digital speed limit signs on Interstate 65, with the goal of preventing accidents in construction zones.
A total of six signs, three each for northbound and southbound traffic, have been placed on I-65 between the Whiteland exit and the U.S. 31 exit at Taylorsville, said Harry Maginity, Indiana Department of Transportation spokesman.
The speed limit signs can be changed to adjust speed limits in 5 mph increments between 45 mph and 70 mph, Maginity said. The signs are being tested as a way to slow vehicles before construction zones.
Today and Tuesday, the state will work with Purdue University researchers to change the speed limits on the northbound signs from a laptop and modem in a vehicle. Based on the traffic flow, the state will experiment with how drivers respond to changes made on the speed limit signs, said Ed Cox, an INDOT engineer.
Purdue researchers will have radar guns to check speeds of vehicles that pass by the signs to determine what the drivers do when they see the sign and the speed limit, Cox said. Drivers will not be ticketed or stopped based on what the radar guns are showing during the test, he said.
This is the first time this type of speed limit sign has been tested in Indiana, said Will Wingfield, INDOT spokesman. However, the technology has been tested and used in other states.
The state wants to use the signs to make entrances into construction zones safer and to avoid rear-end collisions when drivers aren’t aware of slowed or stopped traffic ahead in a work zone.
The state is patching and resurfacing a 10-mile stretch of I-65 between State Road 252 near Edinburgh and State Road 44 at Franklin. Lanes have been narrowed, and traffic has been shifted, Maginity said.
The goal is to allow the state to control the electronic signs from Indianapolis, based on mapping and sensors already in place that measure traffic flow, and change speed limits to account for traffic and conditions, Wingfield said. An algorithm is being developed that would allow the signs to automatically adjust, slowing traffic down as needed based on traffic flow data, Wingfield said.
The state will need a few weeks to compile data collected in testing this week. Cox and the researchers will return to test the algorithm to see if changes to the speed limit are being done correctly to slow traffic as vehicles approach the work zone.