A multilayer data-driven framework for robust structural health monitoring based on a comprehensive application of machine learning and signal processing techniques is introduced. This paper focuses on demonstrating the effectiveness of the framework for damage detection in a steel pipe under environmental and operational variations. The pipe was instrumented with piezoelectric wafers that can generate and sense ultrasonic waves. Damage was simulated physically by a mass scatterer grease-coupled to the surface of the pipe. Benign variations included variable internal air pressure and ambient temperature over time. Ultrasonic measurements were taken on three different days with the scatterer placed at different locations on the pipe. The wave patterns are complex and difficult to interpret, and it is even more difficult to differentiate the changes produced by the scatterer from the changes produced by benign variations. The sensed data were characterized by 365 features extracted from a variety of signal-processing techniques. Automated feature selection methods were then developed using an adaptive boosting algorithm to identify the most effective features for damage detection. With the selected features, five machine-learning classifiers were formulated based on adaptive boosting and support vector machines and achieved 98.5–99.8% average accuracy during random testing and 84.2–89% average accuracy during systematic testing. In addition, other metrics for classifier evaluation generated from a confusion matrix and from a receiver operating characteristic curve are reported.

Despite the increased interest in automation and the expanded deployment of robots in the construction industry, using robots in a dynamic and unstructured working environment has caused safety concerns in operating construction robots. Improving human–robot interaction (HRI) can increase the adoption of robots on construction sites; for example, increasing trust in robots could help construction workers to accept new technologies. Confidence in operation (or self-efficacy), mental workload, and situational awareness are among other key factors that help such workers to remote operate robots safely. However, construction workers have very few opportunities to practice with robots to build trust, self-efficacy, and situational awareness, as well as resistance against increasing mental workload, before interacting with them on job sites. Virtual reality (VR) could afford a safer place to practice with the robot; thus, we tested if VR-based training could improve these four outcomes during the remote operation of construction robots. We measured trust in the robot, self-efficacy, mental workload, and situational awareness in an experimental study where construction workers remote-operated a demolition robot. Fifty workers were randomly assigned to either VR-based training or traditional in-person training led by an expert trainer. Results show that VR-based training significantly increased trust in the robot, self-efficacy, and situational awareness, compared to traditional in-person training. Our findings suggest that VR-based training can allow for significant increases in beneficial cognitive factors over more traditional methods and has substantial implications for improving HRI using VR, especially in the construction industry.