## 3 Analysis and Results
### Visualization Analysis of Keywords
The continued development of human-robot collaboration and automation will be crucial in making construction processes more efficient, safe, and adaptable to diverse environments [40]. (3) Keyword Timeline and Burst  
The timeline diagram reveals the evolving trajectory of research in the field of construction robotics [41]. As shown in Figure 7. It shows that the focus of various topics has shifted over time, with certain milestones and trends emerging at key points [42]. Keywords such as \"construction robot\" and \"construction robotics\" have been frequently cited since 2004, and drew significant attention from 2005. As seen in the timeline, \"construction robot\" gained substantial citations early on (from 2004 to 2005), and its prominence has continued to grow in the field over time. It can be inferred that the study of construction robots began with early technological explorations, and, as robotic technology advanced, more scholars began to focus on its applications in the construction industry. Between 2008 and 2020, several keywords, such as \"construction automation\", \"BIM\", and others, highlight the progress in research related to automation, information modeling, and system integration. With the growing demand for automation and intelligent technologies in the construction industry, research shifted from specific robotic applications to a broader focus on global system design, information management, and other technical aspects. The post-2020 surge in \"cognitive load\" research reflects a shift toward human-centric automation, but this trend remains largely confined to academic prototypes. For example, [PERSON] et al. (2021) demonstrated VR's efficacy in training workers, but real-world adoption lags due to high implementation costs. This gap between innovation and application echoes [PERSON]'s (2021) critique of 'techno-optimism' in construction robotics--a challenge our study highlights as a priority for industry-academia partnerships. This indicates that scholars have started to explore how advanced technologies like AI and virtual reality can enhance the intelligence and functionality of construction robots. The keyword \"cognitive load\" specifically shows how construction robots might self-regulate during high-intensity work, optimizing human-robot collaboration. The emergence of the \"safety\" keyword in  
Figure 7: Timeline visualization of keyword evolution. Burst keywords (red segments) indicate sudden increases in research interest. Generated using CiteSpace 6.3.R1 ([PERSON]’s burst detection algorithm). Data source: Web of Science Core Collection (2002–2024). 2022, with continued growth in 2023, reflects the increasing focus on improving safety on construction sites using robotic technology. Robots can reduce the need for human intervention in high-risk tasks, thereby improving safety. The rapid prominence of \"virtual reality\" shows that the integration of construction robotics with virtual environments is becoming a new research hotspot. This could involve training construction workers, conducting virtual construction simulations, or enhancing human-robot interaction experiences. Additionally, the keyword \"human-robot interaction\", highlighted in 2023, demonstrates the growing importance of effective communication and collaboration between humans and robots as robotic technology matures. As shown in Figure 8. Based on the trends observed in recent years, future research on construction robotics is likely to focus more on the following areas: (1) Intelligence: Keywords such as \"virtual reality\" and \"cognitive load\" suggest that future research will be centered on improving the intelligence of robots, allowing them to adapt to complex environments and collaborate more effectively with human workers [43]. (2) Safety and efficiency: With the increasing demand for safety in the construction industry, learning how to use robotics to reduce safety hazards and enhance construction efficiency will be a key research direction [44].