Active Control of Vibrations Using an Audio Signal Processor

Active control by smart structures is a topic of research for more than two decades now. Promising results have been achieved in reducing vibrations and noise emissions/transmissions using model-based feedback controllers. Most of the contributed work is focused on single panel structures neglecting the fact that real structures like aircraft, for example, consist of a large number of different panels and sub-panels. For such large-scale structures model-based control approaches are challenging and probably not realizable. Recent work show that non model-based velocity feedback control with distributed collocated actuator-sensor pairs achieves comparable control results. Although the implementation of velocity feedback loops is not demanding concerning computational power, a very simple feedback solution is often not sufficient. Additional filters for sensors and actuators as well as limiters are needed in practical applications. In this paper a realization of a velocity feedback controller is presented. Instead of using a rapid prototype system, the controller is implemented on a low-cost audio codec. With this unit a smart structure with collocated actuator-senor pairs is set up in the laboratory. Experiments show the effectiveness and the practical relevance of the chosen implementation.