## 8 Conclusions  
Inspection and monitoring of buildings and infrastructure are important for the success of the project and the longevity of the structure. Multiple people are involved in the inspection and monitoring throughout the lifecycle of the structure. Traditional methods involve visual observations through personally visiting the site, which is time-consuming and adds to the overall lifecycle cost. This article presents a comprehensive review of the literature on robotic inspection of the built environment.  
This research contributes to understanding the potential of robots for the regular inspection of the built environment. The knowledge synthesized from the body of literature is used to highlight different types of robots that have been applied for automated inspection and the different applications these robots can serve within the inspection and monitoring of the built environment and the prevalent research areas.  
The study identified five application domains for use of robots for inspection purposes in the built environment, namely, post-construction maintenance inspection, construction quality inspection, progress monitoring, as-built modeling, and safety inspection. For these inspection domains in the built environment, a variety of robots were used. Drones were found to be the most prevalent, followed by wheeled robots. Other custom robots with varying locomotion and sizes were also developed for a variety of purposes. The study also found eight different research areas that have been studied. Those are autonomous navigation, knowledge extraction, a motion control system, sensing, safety implications, multi-robot collaboration, human-robot collaboration, and data transmission.  
One of the limitations of this review is that it only includes materials written in English. The authors acknowledge that many important studies published in other languages are not included in this review. Another limitation is that this review only covers publications published through April 2022. Owing to the rapid growth in this topic, more articles may have been published by the time this review is made available to the readers. Another limitation is that the review includes only academic publications. Many robotic applications might be developed by corporations and startups who do not publish their research in academic publishing venues, and therefore might have not been represented in this review.  
With the rapid growth in the research on robotics and supporting technologies such as deep learning and computer vision, robots will be utilized more often than they are now in the AECO industry. Future adoption of robotics will require an understanding of the technology by both managers and workers. This systematic literature review will help both researchers and AECO practitioners to develop and implement new robotic solutions. It will also assist construction and facility managers in understanding how robotics fits into their existing processes and how to modify their existing policies in order to adopt and benefit from it.  
This research and the APC was funded by the National Science Foundation (NSF) Future of Work at the Human-Technology Frontier Big Idea under Grant No. 2128948.  
Not applicable.  
Data Availability Statement: The data presented in this study are available on request from the corresponding author. The data are not publicly available as they are confidential.  
The authors declare no conflict of interest.