Final Report Summary - INMAR (Intelligent Materials for Active Noise Reduction)
The objective of the INMAR project was the research and realisation of intelligent, high-performance, adaptive material systems with integrated electronics for different individual applications. These are applicable for noise mitigation purposes - even in highly loaded structures as construction material - in the same manner that common passive or lightweight materials have been used up to now. Aside from the development of the materials or material systems themselves, this research also included their characterisation, simulation tools for the design process, handling and manufacturing techniques as well as the reliability of these material systems. According to common trends in engineering, the development has to be performed on an experimental as well as theoretical and numerical level.
The main objective of smart structure technology is noise and vibration reduction in civil engineering, machine tools, automobiles, trains, and aerospace engineering. Both strongly coupled phenomena limit the design of highly advanced and efficient lightweight structures, whereby nowadays noise is considered one of the worst forms of environmental pollution worldwide. Noise exposure within vehicles significantly contributes to the physical fatigue of the driver and, as a consequence, accounts for significant number of accidents with fatal or serious injuries. Beyond their impact on noise, smart structure technology will for the first time allow for a concurrent lightweight design that enables the efficient use of natural resources in the product itself (less, fuel consumption, less exhaust emission etc). With the upcoming demand of highly efficient, emission less lightweight structures and increased standards for any type of emission, new intelligent materials systems are needed that allow for both highly damped and controllable as well as light but durable structures for any type of high-tech application.
Up to present, many intelligent materials systems such as fibre composites with embedded piezo-ceramics or shape memory alloys are derived, characterised, and applied in smart structures on a laboratory scale without having an impact yet on the design rules for engineered structures or without their application in mass products. Although their potential could be demonstrated and realised to a certain extent in prototype structures, the performance of intelligent material systems is still insufficient. They require an unacceptable electronic periphery, data on their durability and reliability is lacking and, most importantly, are not yet included in standard design and manufacturing processes. These deficits should be overcame by the newly established Integrated Project (IP) INMAR.
The INMAR project was set-up in such a way, that the scientific and technological objectives are reflected in a structure divided in the two clusters technology area and application scenario as shown in the table below. The basic idea of this structure was that the application scenarios focused on the development of active noise reduction concepts for specific 'noise, vibration, and harshness' (NVH) problems and the technology areas provided the required enabling technologies such as the actuator and sensor systems as well as the control strategies and integration techniques. The enabling technologies would be derived in a general manner to cover all considered NVH problems. This would allow the development of technologies ac-cording to the specific needs of the AS and fundamental technologies contributing to the overall objectives on INMAR at the same time. Nevertheless, the enabling technologies still need to be adapted in the application scenario cluster to their specific needs. Such a structure requires a close cooperation across sub-projects and work areas and a detailed adjustment of individual work tasks. In contrary to other Fifth Framework Programme (FP5) or Sixth Framework Programme (FP6) projects where sub-projects are mostly independent without close cooperation's, joint activities and use of synergies between work areas are foreseen within INMAR. This could be realised by partners participating in work areas in both clusters at the same time ensuring the transfer of knowledge in both directions. That way, the technology areas have a cross-functional role following a bottom-up approach whereas the application scenarios have a top-down approach with their specific problems.
The general objectives in the first 18 months were to develop basic technology that is crucial for the success of the application scenarios and to develop concepts for the NVH problems under consideration. Within the first 18 months, these NVH problems were described and the targets defined. A first gateway was defined by evaluating the system approaches and the defined specifications. This gateway has been reached.
In the prototype phase, similar steps have been defined but with more representative elements and more refined strategies. Optimisation of the performance of the systems - both the material system and the noise reduction system - has to be considered to obtain best performance of all the elements. Here, the integration techniques and the life-cycle aspect become more and more important. The application scenarios will be able to give feed-back on first results by refining the specifications for the technology areas. Interference with other systems, feasibility considerations with respect to cost, durability, and reliability can be performed on the system level for the first time. Technical risks most notably arise from meeting standards applied in the respective industries such as durability, reliability, and safety. A second gateway is provided by the evaluation of the achievement after performance, packageability, cost, and interference with other systems. The evaluation again allows for modifications in the work plan for the final phase. The technology areas are now able to define the specifications for material systems needed beyond the scope of the technology area.
A significant progress towards the proof of feasibility, the build-up of samples and systems as well as on their characterization was achieved. All obtained achievements in the technology areas as well as in the application scenarios are well documented in the deliverables and technical reports.
The main objective of smart structure technology is noise and vibration reduction in civil engineering, machine tools, automobiles, trains, and aerospace engineering. Both strongly coupled phenomena limit the design of highly advanced and efficient lightweight structures, whereby nowadays noise is considered one of the worst forms of environmental pollution worldwide. Noise exposure within vehicles significantly contributes to the physical fatigue of the driver and, as a consequence, accounts for significant number of accidents with fatal or serious injuries. Beyond their impact on noise, smart structure technology will for the first time allow for a concurrent lightweight design that enables the efficient use of natural resources in the product itself (less, fuel consumption, less exhaust emission etc). With the upcoming demand of highly efficient, emission less lightweight structures and increased standards for any type of emission, new intelligent materials systems are needed that allow for both highly damped and controllable as well as light but durable structures for any type of high-tech application.
Up to present, many intelligent materials systems such as fibre composites with embedded piezo-ceramics or shape memory alloys are derived, characterised, and applied in smart structures on a laboratory scale without having an impact yet on the design rules for engineered structures or without their application in mass products. Although their potential could be demonstrated and realised to a certain extent in prototype structures, the performance of intelligent material systems is still insufficient. They require an unacceptable electronic periphery, data on their durability and reliability is lacking and, most importantly, are not yet included in standard design and manufacturing processes. These deficits should be overcame by the newly established Integrated Project (IP) INMAR.
The INMAR project was set-up in such a way, that the scientific and technological objectives are reflected in a structure divided in the two clusters technology area and application scenario as shown in the table below. The basic idea of this structure was that the application scenarios focused on the development of active noise reduction concepts for specific 'noise, vibration, and harshness' (NVH) problems and the technology areas provided the required enabling technologies such as the actuator and sensor systems as well as the control strategies and integration techniques. The enabling technologies would be derived in a general manner to cover all considered NVH problems. This would allow the development of technologies ac-cording to the specific needs of the AS and fundamental technologies contributing to the overall objectives on INMAR at the same time. Nevertheless, the enabling technologies still need to be adapted in the application scenario cluster to their specific needs. Such a structure requires a close cooperation across sub-projects and work areas and a detailed adjustment of individual work tasks. In contrary to other Fifth Framework Programme (FP5) or Sixth Framework Programme (FP6) projects where sub-projects are mostly independent without close cooperation's, joint activities and use of synergies between work areas are foreseen within INMAR. This could be realised by partners participating in work areas in both clusters at the same time ensuring the transfer of knowledge in both directions. That way, the technology areas have a cross-functional role following a bottom-up approach whereas the application scenarios have a top-down approach with their specific problems.
The general objectives in the first 18 months were to develop basic technology that is crucial for the success of the application scenarios and to develop concepts for the NVH problems under consideration. Within the first 18 months, these NVH problems were described and the targets defined. A first gateway was defined by evaluating the system approaches and the defined specifications. This gateway has been reached.
In the prototype phase, similar steps have been defined but with more representative elements and more refined strategies. Optimisation of the performance of the systems - both the material system and the noise reduction system - has to be considered to obtain best performance of all the elements. Here, the integration techniques and the life-cycle aspect become more and more important. The application scenarios will be able to give feed-back on first results by refining the specifications for the technology areas. Interference with other systems, feasibility considerations with respect to cost, durability, and reliability can be performed on the system level for the first time. Technical risks most notably arise from meeting standards applied in the respective industries such as durability, reliability, and safety. A second gateway is provided by the evaluation of the achievement after performance, packageability, cost, and interference with other systems. The evaluation again allows for modifications in the work plan for the final phase. The technology areas are now able to define the specifications for material systems needed beyond the scope of the technology area.
A significant progress towards the proof of feasibility, the build-up of samples and systems as well as on their characterization was achieved. All obtained achievements in the technology areas as well as in the application scenarios are well documented in the deliverables and technical reports.