This article describes the development and characterization of the synergistic smart morphing aileron concept, which leverages the properties of two different smart material actuators to achieve performance that exceeds that of the constituent materials. Utilizing the relatively higher work density and phase transformation of shape memory alloys combined with the larger bandwidth and conformal bending of bonded piezoelectric macro-fiber composites, the resultant synergistic morphing design improves the range of static tip deflections, enabling the capability to hold more trim positions over long timescales while still quickly compensating for dynamic loading. By commanding an input of full-range square waves of 0.01-10 Hz to the actuators, first-order time responses were measured and characterized using a common methodology by tracking a relative time constant. Using this method, aeroelastic effects for each actuator and the combined system were characterized in a wind tunnel at 0°angle of attack with flow speeds ranging from 0 to 15 m/s. This novel approach characterized a large-deflection morphing actuation system with multiple smart materials operating over different timescales. The combined system achieved additive amplitude while tracking the faster actuation response of the macro-fiber composite between 0.1 and 1 Hz.

Cost reduction of any design process is always of interest for industries. Simulation work packages tackle this problem since they can quickly provide reliable results that permit detection of critical design issues prior to the prototype phase. A trade-off is then often made between model accuracy and computation speed. In the particular case of electric machines, homogenization techniques are used in order to keep high accuracy while running fast calculations. They are involved in multiple disciplines in which the machine performances are verified such as elec tromagnetic, mechanical, thermal and acoustic domains.This paper aims at defining whether these homogenization methods can be extended from one discipline to another by reviewing them independently of the physical domain.

This paper tackles networked distributed observer 1 and controller design problem over directed graph topology for 2 spatially interconnected systems. Traditional centralized design 3 methods suffer from a lack of adaptability to graph variations 4 incurred by network reconfiguration, communication failures, 5 and redundant sensors integration. In this paper, to handle 6 the foregoing limitations imposed by centralized design, state 7 observers are designed in a distributed manner facilitated by 8 pinning control precepts. On the one hand, this novel approach 9 adds fault tolerance with respect to communication link failures. 10 On the other hand, the proposed approach brings flexibility of 11 integrating additional sensors into the network. In addition, this 12 approach affords a reduction of computational cost. A sufficient 13 condition to guarantee stability of the closed-loop system is 14 derived. The controllers, though in the end implemented in 15 a distributed way, are designed in a centralized framework, 16 where linear-quadratic-regulator theory is adopted to handle 17 the fact that separation principle fails to hold in the net-18 worked observer and controller design. Numerical simulation 19 results of a piezoelectric actuated smart flexible system are 20 presented, and the effectiveness of the proposed design is thereby 21 verified.

Smart structures with integrated macro fiber composite (MFC) piezoelectric transducers have been increasingly investigated in engineering. A simple but elaborate system model of such smart structure not only can predict system dynamics, but also can reduce challenges in application. Therefore, the equivalent force (EF) modeling approach is presented to model the plate-type structures with integrated piezoelectric actuators in a semi-analytical fashion: analytical EF is applied to finite element (FE) structural models. The EF is derived from the bending effort balance between the equivalent loads, and the equivalent loads are developed by introducing the spatial distribution into a generalized Hamilton’s principle. The proposed approach is validated by cantilever aluminum beams with integrated MFC actuators and it is consistent with existing alternative approaches from literature. Then, it is validated on a non-homogeneous composite plate for dynamic applications: a laminated composite plate with integrated MFC actuators was manufactured and both an impact test and MFC drive test were elaborately carried out. The modal validation shows the high fidelity of the EF model and the predicted velocity frequency responds functions (FRFs) agree well with experimental measurement. Being applicable to both numerical and analytical modeling approaches, the EF is actually assigned to the out-plane displacement on the structure and distributed along the edges of the actuators. Therefore, it is convenient to use in EF models. The rotational degrees of freedom could also be eliminated in the EF models without losing structure complexity, since they neither link to the electromechanical coupling nor have a significant kinetic contribution to the system.

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