## 5 Conclusions  
This research investigated the impact of wearable robotic exoskeletons on construction task performance, addressing a significant gap in quantitative analysis of how these assistive devices affect productivity and motion stability in real construction scenarios. The construction industry continues to rely heavily on manual labor despite technological advancements, making solutions that simultaneously reduce physical strain and improve productivity essential for industry advancement.  
The methodology employed a systematic experimental approach examining three representative construction activities--sack carrying task (CT), masonry bricklaying task (MT), and scaffolding installation task (ST)--under both low and high-intensity conditions. Twenty construction workers with relevant experience participated in the study after standardized training with the WIR-WIM-KRA exoskeleton. We collected comprehensive data through IMU sensors positioned at participants' waist and ankle, capturing detailed movement patterns while measuring task completion rates across 2 h work periods.  
Results demonstrated consistent and substantial benefits from exoskeleton use across all dimensions of performance. Productivity analysis revealed significant improvements ranging from 20.0% to 59.5% depending on task type and intensity, with high-intensity tasks showing the greatest benefits. Stability assessment through IMU data indicated a 24.8-35.4% reduction in postural sway area and improved movement consistency, particularly during challenging physical tasks. The time-dependent analysis showed that exoskeleton benefits continuously increased throughout the 2 h work period, with average productivity advantages growing from 23.9% initially to 40.1% in the final interval, demonstrating both worker adaptation to the technology and substantial fatigue mitigation effects.  
The discussion identified key factors influencing exoskeleton effectiveness, including task characteristics, work intensity, and adaptation time. The findings suggest that construction managers should prioritize exoskeleton implementation in high-intensity tasks involving repetitive bending and lifting motions and should account for adaptation periods when implementing this technology. The comprehensive benefits observed--spanning productivity enhancement, stability improvement, and fatigue reduction--position wearable robotic exoskeletons as valuable tools that augment human capabilities rather than replacing workers.  
In conclusion, this research has empirically demonstrated that wearable robotic exoskeletons serve as more than supplementary assistive devices--they function as significant productivity enhancers that simultaneously address the physical demands of construction work. As industry continues to face challenges of labor shortages and physically demanding tasks, exoskeleton technology offers a promising middle path that enhances human capabilities while potentially transforming construction practices.  
Conceptualization, J.O., G.Y.C. and H.K.; methodology, J.O., G.Y.C. and H.K.; validation, J.O., G.Y.C. and H.K.; investigation, J.O.; writing--original draft preparation, J.O.; writing--review and editing, J.O., G.Y.C. and H.K. All authors have read and agreed to the published version of the manuscript.  
This research was by a grant (RS-2022-00143493) from a Digital-Based Building Construction and Safety Supervision Technology Research Program funded by Ministry of Land, Infrastructure and Transport of Korean Government.  
The study was conducted according to the guidelines of the Declaration of Helsinki and approved by the Institutional Review Board of DANKOOK UNIVERSITY (DKU 2020-09-027, date of approval 14 September 2020).  
Written informed consent has been obtained from the patient(s) to publish this paper.  
All data, models, or code generated or used during the study are available from the corresponding author by request.  
The authors declare no conflicts of interest.