Welcome to the STOL, one of the newest facilities at the Turner-Fairbank Highway Research Center. Known also as the Saxton Lab, this testing ground provides research that is advancing next-generation transportation. STOL is surrounded by extensive connected road, traffic signal, and mobile sensing networks that enable a broad range of research needs. The activities at this laboratory support three key research focus areas: cooperative driving automation; analysis, modeling, and simulation tools; and intelligent transportation system technologies.

A team of transportation engineers at STOL is working on various simulation-based projects like the hardware-in-the-loop demonstration shown in this video. Through this experiment, we are able to visualize and understand the impact of connected-vehicle technology for applications like adaptive cruise control.

This proof-of-concept vehicle is known as the CARMA^SM vehicle, which is used to conduct cooperative automation research, enabling self-driving cars. The vehicle is equipped with many sensors and a computer with open-source software. Sensors allow the vehicle to precisely position and orient itself on the road, follow the lane, and detect other objects to ensure safe operations during automated testing. This CARMA^SM vehicle also includes a Global Positioning System sensor, which uses satellites to provide vehicle location and timing; an inertial measurement unit to gauge acceleration and provide that information to the CARMA^SM software; and an onboard unit—or wireless radio—that enables communication with other connected vehicles and the monitoring infrastructure. In addition to sensors, the vehicle contains drive-by-wire systems that allow vehicle motion control.

Platooning is a critical application for researching the impact of connected and automated vehicles on our Nation's roadways. Here, we see a lead CARMA vehicle using basic safety messages sent via radio to coordinate a platoon. The following vehicles merge in behind the leader and use connected messages to coordinate shorter gap distances and higher speeds to increase the overall safety and efficiency of the highway.

This proof-of-concept vehicle known as the CARMA vehicle, is used to conduct cooperative automation research, enabling self-driving cars. The vehicle is equipped with many sensors and a computer with open-source software. Sensors allow the vehicle to precisely position and orient itself on the road, follow the lane, and detect other objects to ensure safe operations during automated testing. CARMA vehicles are equipped with radar on the sides and front to detect objects on the roadway as well as their speed and motion. The front-mounted radar is midrange to long-range to detect objects directly in the path of the vehicle. A 32-beam rotary light detection and ranging (LiDAR) tool on top of the vehicle helps determine the car's surroundings and position. Three special cameras are also on board that detect objects, pedestrians, and vehicles directly in the path of the CARMA vehicle.

This scaled-down truck is one-tenth the size of the CARMA truck that it is modeled after and was created to aid the assessment of cooperative driving automation (CDA) capabilities. Equipped with similar technology as full-sized CARMA vehicles, the CARMA 1Tenth vehicles enable CDA research on a low-cost robotic platform without the need for costly test tracks.

Once research is validated on 1Tenth vehicles, it can be further studied on full-scale vehicles. These 1Tenth vehicles are a safe and practical tool for developing and testing CARMA CDA capabilities.

Connected mobile traffic sensing systems come in the form of trailers used to support research in locations without dedicated power or where the study duration is relatively short. The trailers have a mast to hold a roadside unit and a variety of sensors, which may include closed-circuit television cameras, light detection and ranging (LiDAR) tool and traffic radars, based on the intended research. The system is powered using solar panels and automotive-grade batteries. These trailers are available for loan to public agencies to support both research and training in connectivity.

Roadway weather is a critical component of the research conducted at the Saxton Lab. Researchers use an automated weather station equipped with a variety of weather sensors that detect air temperature, precipitation, relative humidity, and solar radiation.