DEVELOPMENT OF A PLATFORM TECHNOLOGY FOR AUTOMATED VEHICLE 

RESEARCH – COOPERATIVE ADAPTIVE CRUISE CONTROL

BACKGROUND

The Federal Highway Administration (FHWA) Office of Operations 

Research and Development, located at Turner-Fairbank Highway 

Research Center (TFHRC), added five new research vehicles to 

FHWA’s Innovation Research Vehicle Fleet. This fleet offers an 

experimental connected automation research platform that provides 

advanced capabilities for future operational concepts and supports 

their evaluation. In addition, the fleet’s research platform enables 

full automatic control of longitudinal movements (such as 

acceleration and braking) with the flexibility to support lateral 

control (such as steering controls) for future autonomous vehicle 

research. 

Cooperative Adaptive Cruise Control (CACC) is the first 

operational implementation developed and tested on the new 

research platform. CACC allows vehicles to communicate with 

each other to enable a group of vehicles to implement coordinated 

advanced applications on freeways and arterials. For example, 

researchers have leveraged the longitudinal control capabilities 

provided by the research vehicle platform to deliver speed 

commands in real-time in order to experiment with speed 

harmonization. The platform technology also allows the vehicles 

to use 5.9 GHz Dedicated Short Range Communication (DSRC) 

and cellular communications to share speed, heading, location, and 

gap information with each other for advanced applications (such as 

platooning) in managed lanes.

The CACC implementation will provide the ability to test the open 

architecture of the vehicle fleet technology platform and assess the 

ability of researchers to use the vehicle fleet to support the study of 

operational concepts and connected automation applications.

RESEARCH APPROACH

To advance emerging concepts, technologies, and applications, the 

vehicles are retrofitted to take advantage of the latest in-vehicle 

safety technologies—including Automatic Collision Prevention, 

Forward Collision Alert, Lane Departure Warning, Side Blind 

Zone Alert, and Full-Range Adaptive Cruise Control. The research 

team developed the CACC strategy by layering a new control 

system on top of the vehicle’s factory-equipped adaptive cruise 

control system. This allows an onboard computer to safely intercept 

the data transmitted from the vehicle’s forward looking sensors 

and camera and effectively command the vehicle’s speed by 

accelerating or braking. 

The three major components of the research platform are: 

Communications, Positioning, and Vehicle Control.

COMMUNICATION

The vehicle fleet is equipped with 4G/LTE, Wireless Fidelity (WiFi), and DSRC connectivity through multiple devices, which 

maintain maximum flexibility for future communication needs. 

The platform uses the communication media of choice for 

communications-based active safety systems that will enable V2V 

and V2I wireless communications. 

Office of Operations 

Research and Development CACC

www.fhwa.dot.gov/research/

Innovation Research Vehicle Fleet Benefits: 

• Enables researcher-friendly access to longitudinal control 

using original equipment manufacturer (OEM) developed 

safety systems.

• Supports software and application development with modelbased tools, such as MathWork’s Simulink and MATLAB. 

• Supports vehicle-to-vehicle (V2V) and vehicle-toinfrastructure (V2I) communication using DSRC and cellular 

(4G/LTE).

For more information, please contact: 

Taylor.Lochrane@dot.gov

Test Vehicle Equipped with Cooperative Adaptive Cruise Control Technologies
Office of Operations

Research and Development

POSITIONING

The vehicles fleet is equipped with a localization system that 

provides continuous positioning for ground vehicles. This system 

provides a multisensor fusion of dual-GPS receivers, inertial 

sensors, and wheel speed sensors to provide real-time position, 

orientation, velocity, and time information. Real Time Kinematic 

(RTK) corrections, available from the base station at TFHRC, are 

also used to enhance the precision of the absolute geodetic vehicle 

positions. All data are continuously updated even if an immediate 

GPS fix is not available, allowing for operation during GPS 

degradation or complete signal loss. 

VEHICLE CONTROL

Vehicle longitudinal control is achieved using a locally created 

software control module consisting of a set of two independent 

electronic control units (ECU). 

• The Throttle ECU will selectively filter out torque commands 

originating from the control module while injecting new torque 

commands as commanded by the researcher. 

• The Brake ECU will selectively filter out brake or deceleration 

commands originating from the control module while injecting 

new commands as commanded by the researcher. 

The new vehicles will serve as the next generation research vehicle 

fleet and will provide the capability to develop and test connected 

automation concepts over the next 5 years.

Cell Tower

GPS Satellite

Radar 

Dedicated Short

Range Communication

Cooperative Adaptive

Cruise Control

Cooperative Adaptive Cruise Control Platoon Scenario

For more information, please contact: 

Taylor.Lochrane@dot.gov

Cooperative Adaptive Cruise Control Equipment Platform

Hybrid DSRC and

Cellular Antenna

Factory

Antenna

GPS Antenna

Control Systems

FHWA-HRT-15-032