A multi-criteria decision support framework for autonomous truck-mounted attenuator deployment in mobile work zones accounting for economic and technical feasibility

Abstract

Mobile short-term operations (e.g., patching, mowing) are essential for maintaining roadway functionality but can expose work-zone crews to high-risk conditions and environments, including sideswipe and rear-end crashes. The Autonomous Truck Mounted Attenuator (ATMA) is an innovative technology adopted by several transportation agencies as a safety countermeasure. ATMA operations consist of a leader vehicle (LV) that conducts maintenance work and a follower vehicle (FV) that operates autonomously, providing a safety buffer in mobile work zones. By removing the human operator from the FV, the ATMA system eliminates the possibility of injury to the worker in that vehicle. Despite its effectiveness, ATMA, as a relatively new technology, poses economic and operational feasibility challenges for the DOTs, requiring consideration of multifaceted factors. This research developed a decision-making tool based on a framework to evaluate the economic and operational feasibility of deploying ATMA systems. The decision-making tool includes two primary modules. The first module pertains to a Benefit-Cost Analysis (BCA), which assesses economic feasibility using a benefit-cost ratio (BCR) and sensitivity analyses. The second module is a Multi-Criteria Decision Analysis (MCDA) ranking module for facilities with both interrupted and uninterrupted traffic. This module uses key input variables (e.g., roadway geometry conditions and traffic flow) to evaluate ATMA deployment feasibility. This MCDA applies weighted criteria and evaluates three site alternatives to identify the ideal route segments with appropriate conditions for deployment. Several methods were incorporated into this tool, including the Weighted Sum Method (WSM), the Weighted Product Method (WPM), the Preference Ranking Organization Methods for Enrichment Evaluations (PROMETHEE), and the Technique for Order Preferences by Similarity to an Ideal Solution (TOPSIS). The integrated framework provides a structured approach to assessing ATMA deployment feasibility, producing outputs such as economic indicators (i.e., BCR) and site alternative rankings. Sensitivity analysis indicated that a higher BCR was obtained when the average annual crashes involving TMAs increased. Also, the BCR increased with a longer ATMA life cycle, and the BCR decreased when the ATMA system integration cost increased.