An Active Mass Damper Based on Wireless Sensors and Digital Control

With the increasing demand on structural safety, the concept of structural control is conceived to protect the controlled structure by reducing the response due to external excitation, such as earthquake and strong wind. An active mass damper (AMD), i.e., the active form of the passive device known as tuned mass damper (TMD), is a typical way to implement structural control. An existing laboratory three-storey steel frame was used to validate different control schemes. The frame is mounted on a single-axis shaking table simulating the ground excitation. Four single-axis wired accelerometers were mounted on each level (ground and floors of the frame). A mass cart driven by a DC motor, a DC motor position analog controller, and a controller board complete the early bed-test realization. Recently wireless sensors and a digital position controller were introduced to update the AMD performance. In this paper the frame specimen is simulated by a numerical model allowing the authors to design and test the control laws without any risk of damaging the physical model. Such a modeling is pursued by an approach different from the one adopted in early studies.