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TWINSA
In-situ Calibration
In-Situ Dual Calibration System (lDCS) principle: Calibrate sensors and equations independently.
Based on our understanding of the nature of force measurement, a critical question arises: Can we address these challenges by separating sensor calibration from equation calibration, allowing both to be handled independently without the need to remove load-bearing components from the structure? Furthermore, the calibration process should not interfere with the current load conditions of either the components themselves or the structure as a whole.
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Smart Adapters facilitate sensor and equation calibration in one mechanical process as follows:
Sensor replacement & calibration:
The actuation device pushes the wedges outward, provides space to replace and calibrate the load cells without affecting the structure's load- bearing condition.
Friction reversal:
As the wedge continues to push, friction initially decreases to zero and then gradually increases in the opposite direction. Eventually, it reaches a friction reversal state, where the friction coefficient matches the previous magnitude but in the opposite direction.Throughout this process, system height is maintained within a 0.05 mm variation.
Equation Calibration:
During the friction reversal state, the recorded actuation force is used in a two-variable equation with applied force and the friction coefficient, enabling precise calculations.
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During monitoring, the load to be measured is decomposed into horizontal components, which are captured by the passive sensor after overcoming friction. The F-T relationship as below.
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During in-situ calibration, The hydraulic jack pushes the wedges aside to reach friction reverse state, the F-Tâ€Equation is then below.
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F:Force applied.
T: The load cell reading.
T' the force exerted by actuator.