Cable Tension Identification for Short Cables with Added Mass Based on Single-point Measurement

Abstract

For short cables with complex boundary conditions, the frequency-based method for cable tensionidentification relying on string/beam theoretical models yields significant errors. The introduction of the concept of Effective Vibration Length(EVL) allows the frequency method to circumvent the influence of boundary conditions. To address the limitations in EVL identification, this paper proposes a single-point measurement-based cable tensionidentification method for short cables under addedmass conditions. Its core advantages are simplifying the acceleration sensor for vibration signal acquisition and eliminating the original methods reliance on mode shape calculation to determine virtual hinges. During optimization, a length segment is selected and divided into multiple virtual hinge points; effective vibration lengths corresponding to these points are calculated under various mass conditions to generate a virtual hingeeffective vibration length diagram. Leveraging the invariant virtual hinge position and effective vibration length across different conditions, the true optimal effective vibration length is locked via curve intersections, enabling high-precision cable tensionidentification with a single sensor and without exact boundary conditions. Numerical simulations validate the robustness and accuracy of the method. Under various complex boundary conditions and mass block arrangements, the relative error in cable tension identification is generally below 3%, demonstrating good engineering adaptability. A full-scale indoor experiment further confirms that in a short cable with unknown boundaries, using only single-point accelerometer measurements and two added mass block conditions, the cable tension identification error is as low as 1.15%.