This presentation introduces a novel remote acoustic inspection method for concrete structures using controlled water droplet impacts. The technique enables safe, non-contact detection of debonding, voids, and surface defects in large-scale infrastructure without scaffolding or direct access. Attendees will learn the fundamental principles of droplet-induced impact acoustics, practical deployment approaches, and key signal-processing methods that enhance defect sensitivity. The session applies effective adult learning principles by integrating visual demonstrations, real field data, and step-by-step explanations that connect theoretical concepts with practical inspection workflows.

Participants will be able to immediately apply several takeaways in their day-to-day work, including how to select appropriate droplet sizes and firing frequencies, how to interpret acoustic signatures to distinguish sound from defective regions, and how to integrate the technique into existing inspection routines. Field case studies—from bridge decks to building façades—will highlight implementation strategies, equipment considerations, and lessons learned. The presentation provides actionable knowledge for engineers, inspectors, and asset managers seeking safer and more efficient methods for concrete condition assessment.

Despite the common recognition of operational risk management as essential in the construction industry, construction workers face a wide array of poorly mitigated risks on the jobsite. To better mitigate these risks on construction sites, augmented reality (AR) is increasingly being used in the construction industry to improve efficiency, safety, and productivity. For example, AR is proposed for providing on-site workers with real-time instructions, information, and guidance through wearable AR devices such as smart glasses or helmets. These devices can overlay digital information, such as blueprints, measurements, or step-by-step instructions, onto the physical environment, assisting workers in executing tasks accurately and efficiently. However, current AR construction safety tools only provide passive information for the user to then decide how to use that information. This study leverages advanced computer vision coupled with AR to work with site managers and on-site workers to make operational safety decisions using real-time, visual information of potential safety risks and hazards. First, machine learning (ML) models using the YOLOv11 were implemented. These models were trained on existing personal protective equipment (PPE) datasets and are capable of real-time detection of people on video streams and whether or not they are wearing a defined set of PPE. Then the models were tested in the lab by creating a local ML computing environment on a laptop, a webcam stream, and a remote camera stream from Microsoft HoloLens to detect the presence or lack of PPE worn. The detection results were compiled and displayed in real-time on a web-based, user-friendly interface developed with Hypertext Preprocessor (PHP) and on a real-time, heads-up display using Microsoft HoloLens 2. The system was successfully field-tested on a construction site.

The use of collaborative robots (cobots) in laboratory settings enables ultrasonic inspections in immersion, air, and contact configurations through a single mechanical solution. Traditional small gantry-style immersion tanks often lack features such as force-feedback control and fully programmable axes of motion. Cobots, designed to work safely alongside humans, support streamlined workflows for complex inspections while offering unique capabilities not typically available in other inspection platforms.

Through programmable trajectories, integrated force control, and highly repeatable positioning, cobot-assisted workflows can significantly improve inspection efficiency in a flexible laboratory environment. Beyond the standard features included with most cobots, additional software tools are available to further accelerate path planning and reduce the need for operator programming skills. The pivoting base and adaptable kinematics of cobot arm systems allow for quick, seamless transitions between inspection techniques, enabling inspectors to spend more time collecting high-value data and less time on the physical labor of moving between stations.

This presentation highlights how cobots have improved workflow in our laboratory and how they can elevate nondestructive testing processes more broadly. The workflow for inspecting a new part, examples of various inspection environments, and practical tips for maximizing the value of a cobot system are all discussed.

Remote acoustic inspection using a string-shooter impact device offers a practical and safe alternative for evaluating tiled and concrete surfaces located in high or inaccessible areas. The method enables suspended wall inspection, allowing the device to be lowered along building façades, as well as ground-based inspection of tunnel ceilings without scaffolding or direct access. Furthermore, the compactness and simplicity of the mechanism make it a strong candidate for integration with unmanned aerial vehicles, providing a pathway toward fully remote tapping inspection at elevated locations.
In this study, we successfully developed a downsized and lightweight string shooter designed specifically for suspended deployment. The reduction in size was achieved without sacrificing impact performance, ensuring sufficient acoustic excitation for detecting debonding in tiled surfaces. A major technical advancement in this work is the improvement of the roller mechanism, which has historically been a critical durability bottleneck. The redesigned roller significantly increases operational life and reliability during repeated high-speed string release and retrieval cycles.
Experimental results and preliminary field evaluations demonstrate that the enhanced system provides stable impact energy, improved durability, and consistent acoustic responses suitable for defect identification. These improvements collectively contribute to a more practical and field-ready inspection tool. The proposed technology offers a promising path toward safer, more efficient, and more scalable high-elevation acoustic inspection, and it broadens the potential applications of remotely operated NDT systems for infrastructure maintenance.