Current and future industrial applications of active noise control

The status of active noise control in terms of its application to industrial problems is discussed and reasons for the apparent lack of enthusiasm for the technology by industry are postulated. An industrial installation in which the author was involved is used as an example to illustrate the complexities involved and the reasons why implementation costs are so high. The future of active noise control in industry is dependent on a number of issues associated with hardware configuration and cost, user friendly software, generalisation of system design, development of low-cost, rugged actuators and sensors together with an acceptance of what is possible and what is not. Novel approaches to achieving the control objective of reduced noise levels at the ears of industrial employees, which sidestep limitations imposed by the physical properties of sound and vibration fields, are also required to enable practical application of the technology in many cases. One such novel approach, which involves virtual sensing combined with very local control and beam steering that tracks a person's ear is discussed. (c) 2005 Institute of Noise Control Engineering.