The drive to satisfy customer expectations has led vehicle manufacturers to place increasing importance on achieving high levels of vehicle refinement in their products. Manufacturers have traditionally addressed this issue through the application of passive noise and vibration control measures, and have devoted significant time and resource into developing ever more complex suites of NVH material. Although conventional passive NVH treatments are an effective means of addressing high frequency noise and vibration, it is difficult to achieve satisfactory results at low frequencies without incurring a considerable weight penalty. This has led to the development of active systems that are capable of achieving significant improvements in vehicle refinement with the minimum of additional weight. Over the past 20 years Lotus Engineering has developed several different active noise and vibration control technologies to address specific issues in vehicle refinement. These technologies are described here, along with a discussion of the technical challenges involved. The paper also examines the work currently being undertaken to develop the next generation of active noise cancellation systems that will take this technology into volume production on mainstream vehicles.
展开▼
