Within the framework of the German national project multiSat multifunctional composite structures for satellite applications are developed. The objective is the integration of passive and active functions into the load-bearing spacecraft structure by using suitable materials, components and mechanisms. The passive functions include heat transfer, radiation shielding and protection against space debris impacts, whereas the active functions comprise electric energy and data transfer and vibration reduction. Due to their multi-layer build-up composite materials are suitable for functional integration since each layer can be defined and designed to provide one or more specific functions. The concept of a multifunctional structure allows for the reduction of the overall satellite mass and of installation space required for subsystems. It also opens up new opportunities for highly integrative and standardized production processes and lower total costs and time for manufacturing, qualification and launch. This paper describes the development and design of a concept for a multifunctional sandwich panel and the results of the analyses, numerical simulations and experiments conducted at coupon level.

An optimized driving comfort with a low interior noise level is an important intention in the passenger car development process. The interior noise level caused by the dynamic interaction between the rolling tyre and the rough road surface and transmitted via the car-body is a significant component of the entire noise level. To reduce the road induced interior noise, in general, the chassis system has to be optimized. Passive measures often induces a trade-off between vehicle dynamics and driving comfort. To overcome this disadvantage in this paper, the development and realization of an active measure is proposed. For the purpose of active mechanical decoupling, an active control system is developed, the feasibility of the integration is investigated and its noise reduction potential is identified by vehicle tests. In a first step, a classical multi-channel and experimental-based structure-borne transfer path analysis of the full vehicle is realized to determine the dominant transfer paths. The concept for the active mount system (active mounts, multi-channel control system, sensors) is developed and parametrized by system level simulation. Mechanical components and power electronics of the active system are designed, manufactured and tested in the laboratory. Subsequently, the entire active system is integrated into the vehicle. The broadband adaptive feedforward algorithm is extended by certain measures in order to improve robustness and performance. Full vehicle tests are used to quantify the required specifications and the achieved effectiveness of the active vibration control system.

In this paper, an approach for conceptual development for vibroacoustic metamaterial structures for realization in aerospace applications is presented. Vibration reduction in the frequency range up to 500 Hz has been evaluated for a composite launcher interstage, designed as a vibroacousitc metamaterial structure based on the local resonance effect. The study involves the analysis of relevant requirements for integration, available space and additional mass. Two approaches for the structural design have been considered. The first approach implies a modification of the host structure to achieve local resonances. The second approach considers adding resonators to compose a vibroacoustic metamaterial structure. Vibration attenuation potential of the interstage as vibroacoustic metamaterial structure is evaluated and designed using finite element method (FEM).

Automated driving functions are expected to increase both the safety and ride comfort of future vehicles. Ensuring their functional safety and optimizing their performance requires thorough testing. Costs and duration of tests can be reduced if more tests can be performed numerically in a feasible simulation framework. This simulation setup must include all subsystems of the autonomous vehicle, which significantly interact with the system under test. In this paper, a modular model chain is presented, which is developed for testing systems with an impact on vehicle motion. It includes trajectory planning, motion control, and a model of the vehicle dynamics in a closed loop. Each subsystem can easily be exchanged to adapt the model chain with respect to the simulation objectives. As a use case, the testing of an active suspension control system is discussed. It is designed directly for use in autonomous cars and uses inputs from the vehicle motion planning subsystem for planning the suspension actuator motion. Using the presented closed-loop model chain, the effect of different actuator control strategies on ride comfort is compared, such as curve tilting. Furthermore, the impact of the active suspension system on lateral vehicle motion is shown.