Design of a Statically Balanced Remote-Center Monitor Mount Using Torsional Springs

Abstract Prolonged monitor use in modern work environments often leads to improper viewing posture and visual discomfort. To address this issue, this study proposes a novel height-adjustable monitor mount mechanism that maintains ergonomic viewing conditions while significantly reducing the operating effort required for height adjustment. The design integrates two key mechanical principles: the Remote Center of Motion (RCM) and the Statically Balanced Mechanism (SBM). The RCM concept ensures that the monitor maintains a nearly constant distance and perpendicular viewing orientation relative to the user's eyes throughout vertical adjustment. A six-bar linkage incorporating RCM characteristics is synthesized using geometric constraint methods to achieve the desired lifting trajectory. Dimensional analysis and motion simulation confirm that the approximate RCM point remains located near the user's eye position, with positional deviation less than 8 mm. To reduce the required operating force, torsional springs are strategically installed to achieve static balancing. The spring parameters and installation locations are optimized using a genetic algorithm to minimize variation in total potential energy across the mechanism's motion range. The optimized configuration reduces the lifting force by approximately 80%, enabling smooth, effortless adjustment. A physical prototype is fabricated, and experimental validation demonstrates consistent ergonomic alignment of the monitor and confirms the predicted reduction in operating force. The proposed mechanism provides stable, ergonomic monitor positioning and user-friendly operability, making it suitable for multi-monitor workstations and human-centered equipment design. The design methodology also offers generalizable guidance for future developments of statically balanced articulated mechanisms.