Background: Efficient and safe instrument exchange remains an important challenge in robot-assisted laparoscopic surgery (RALS). Current workflows require human assistance, increasing staff workload and contamination risk. The modular design of the AdLap robotic laparoscopic instruments enables automated exchange of instrument shafts. This study presents the development and validation of the Instrument Carousel Exchange System (ICES). Methods: An automatic ICES was developed for the AdLap robotic surgery platform of the Delft University of Technology. The prototype was designed to hold six Shaft-Actuated Tip-Articulating (SATA) modular instrument shafts (SATA instrument line, SATA Medical, Amsterdam, The Netherlands) and focused on compactness, robustness, modularity, and rapid disassembly for cleaning and sterilization. System performance was evaluated using repeated autonomous instrument exchange cycles without user interaction. Reliability, alignment tolerance, safety, and exchange duration were assessed. Results: The ICES prototype was successfully designed, manufactured, and tested. Repeated functional testing demonstrated reliable autonomous instrument shaft exchange without human intervention. The system tolerated minor alignment deviations while maintaining stable and safe operation. The mean time for a complete instrument shaft exchange was 84 s (SD = 10 s). The modular architecture allowed straightforward disassembly and maintenance while preserving structural integrity and compact design. Conclusions: The developed ICES represents a substantial step toward fully automated modular instrument handling in RALS. Automated instrument exchange may reduce staff workload and minimize contamination risk during procedures. Future work will focus on improving automation speed, alignment efficiency, and autonomous reinsertion of the instrument shaft through the trocar to further enhance clinical applicability. ... Read more