Safe-D: Safety through Disruption

Automated Truck Mounted Attenuator



Truck-Mounted Attenuators (TMAs) are energy-absorbing devices added to heavy shadow vehicles to provide a mobile barrier that protects work crews from errant vehicles entering active work zones. In mobile and short-duration operations, drivers manually operate the TMA – keeping pace with the work zone as needed to function as a mobile barrier protecting work crews. While the TMA is designed to absorb and/or redirect the energy from a colliding vehicle, there is still a significant risk of injury to the TMA driver when struck.

TMA crashes are a serious problem in Virginia where they have increased each year from 2011 (17 crashes) to 2014 (45 crashes),2 despite a decrease in the number of active construction sites between 2013 and 2014. Although various efforts have been made to improve TMA driver crashworthiness (e.g., by adding interior padding, harnesses, and supplemental head restraints),1 the most effective way to protect TMA drivers may be to remove them from the vehicle altogether.

Recent advances in automated vehicle technologies—including advanced sensing, high-precision differential GPS, inertial sensing, advanced control algorithms, and machine leaning—have enabled the development of automated systems capable of controlling TMA vehicles. Furthermore, the relatively low operating speeds and platoon-like operating movements of leader-follower TMA systems make an automated control concept feasible for a variety of mobile and short-duration TMA use cases. This project seeks to develop an automated control system for TMA vehicles using a short following distance, leader-follower control concept which will remove the driver from the at-risk TMA vehicle.

Project Highlights

  • A leader-follower ATMA technology package was designed and built during this project that successfully operates at speeds up to 15mph in environments with dependable GPS signal and at commanded following distances between 50-400 feet.
  • An integration plan was developed to guide future phases of the project with a focus on transitioning ATMA operations from closed-course test track operations to live mobile work zone operations in live highway environments.
  • A demonstration video was created to highlight the capabilities and features of the ATMA technology package

Final Report

Final Report VTTI-00-022

EWD & T2 Products

Design Workshop– Meeting slides that were presented during a Design Workshop held at VTTI on March 11, 2020
with ATMA consortium partners and TMA subject-matter experts from Virginia.

Training Document – can be used to train TMA management and operators on the
purpose and use cases of ATMAs, functions, and use of the ATMA system, and an overview of
the internal and external human-machine interfaces.

ATMA Integration Plan–  includes recommendations for a progression of ATMA testing phases prior
to use on live, public roadways. The plan includes the nature of testing to be conducted, goals to
be accomplished, criteria for successful completion, recommended facilities, and personnel and
staffing recommendations, and an overview of recommended training for management-level
stakeholders, ATMA operators, and operational work crew members.

The project team created a demo video the showcases the abilities of the ATMA.

VDOT funded additional ATMA research activities in fiscal year 2021.

VTTI funded additional data collection and analysis activities in 2021 to provide additional ATMA performance metrics.

VTTI is continuing discussions with consortium members to fund future phases of the program

Student Impact Statement – Alli Rossi-Alvarez (pdf): The student(s) working on this project provided an impact statement describing what the project allowed them to learn/do/practice and how it benefited their education.


Mollenhauer, M., White, E., (2020). Automated Truck Mounted Attenuator (00-022) (V2) [Data Set]. Safe-D National UTC.

White, E., Mollenhauer, M., Talledo Vilela, J.P. (2021). Design and Development of an Automated Truck Mounted Attenuator (Report No. VTTI-00-022). Safe-D National UTC.

Mike Mollenhauer presented the status of the ATMA project and the capabilities of the system at the Autonomous Maintenance Technology Pooled Fund Study Annual Meeting on October 26th, 2020. This presentation was attended by 43 attendees, many of which were representatives from their respective state’s Departments of Transportation.

Mike Mollenhauer presented the ATMA project goals and status at the Annual Convention and Traffic Expo (ATSSA) on January 27th, 2020. This presentation was attended by an estimated 45 attendees in New Orleans.

Mike Mollenhauer presented the performance monitoring results for the ATMA project to the funding consortium members at the Autonomous Maintenance Technology Pooled Fund Meeting on April 15th, 2021

Final Dataset

The final datasets for this project are located in the Safe-D Collection on the VTTI Dataverse; DOI: 10.15787/VTT1/AT0RHF.

Research Investigators (PI*)

Mike Mollenhauer (VTTI)*
Zac Doerzaph (VTTI)

Project Information

Start Date: 2019-02-25
End Date: 2020-08-24
Status: Complete
Grant Number: 69A3551747115
Total Funding: $670,833
Source Organization: Safe-D National UTC
Project Number: VTTI-00-022

Safe-D Theme Areas

Automated Vehicles
Connected Vehicles

Safe-D Application Areas

Vulnerable Users
Operations and Design
Vehicle Technology
Freight and Heavy Vehicle

More Information

UTC Project Information Form

Sponsor Organization

Office of the Assistant Secretary for Research and Technology
University Transportation Centers Program
Department of Transportation
Washington, DC 20590 United States

Performing Organization

Virginia Polytechnic Institute and State University
Virginia Tech Transportation Institute
3500 Transportation Research Plaza
Blacksburg, Virginia 24061