Experimental Characterisation of Hyperelastic Materials for Use in a Passive-Adaptive Membrane on MAVs Wing

Abstract

The paper focuses on the experimental characterization of hyperelastic of the shelf materials in an effort to implement a membrane skin on a low speed asymmetric wing, in order to assess the benefits of flexible lift surfaces. To better determine the best strain energy function definition for the membrane materials, the most notable hyperelastic constitutive models were used together with experimental uniaxial and equiaxial planar tests. For the experimental equi-biaxial test a special loading device was designed and built in the laboratory. The strain measurements for the experimental tests were conducted using digital image correlation, for increased data precision. From the available constitutive material models taken into account, the best for this application proves to be the Yeoh model, as the experimental strain-stress data has a close match for small as well as large strain values. Numerical simulations using finite elements and the Ansys software were performed to predict the materials behavior.

Statistical Analysis of Raw and Potable Water Quality from a Preparation Plant, as a Basis to Purpose the Re-schedule of the Physico-Chemical Current Routine Analysis Periodicity

“…Such type of extended and deepened statistical analysis is used in many fields and is absolutely necessary for data processing [24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39][40][41][42][43], related also to environmental issues [44][45][46][47][48][49][50][51][52][53][54][55][56][57]. Resolving the environmental issues induced by pollution will increase the quality of human life, as well as of the environment [58].…”

A Self–Tuning Intelligent Controller for a Smart Actuation Mechanism of a Morphing Wing Based on Shape Memory Alloys

“…To evaluate this material, the LAMSI team developed an experimental bench for testing, the setup of which, together with all testing results regarding the SMA wires used as actuators in our application, were presented in detail by our colleagues from LAMSI in the papers published on this subject [42,50]. The material constants used for SMA actuator modeling were: length 1.8 m; cross-section (6 wires, 0.7 mm 2 each) 4.2 × 10 −6 m 2 ; martensite start (finish) temperature Ms (Mf) 58 (5) • C; Austenite start (finish) temperature As (Af) 30 (85) • C; Clausius-Clapeyron coefficient 7 × 10 6 Pa/ • C; maximum phase transformation strain 0.1045 m/m; Young's modulus of austenite (martensite) EA (EM) 52 (22) GPa; resistivity of austenite (martensite) 8.2 (7.6) × 10 −7 Ω × m; density 6450 kg/m 3 ; latent heat of phase transformation QPT 100 × 10 6 J/m 3 ; specific heat C P 320 J/kg/ • C; convection coefficient 18 W/m 2 / • C [50].…”

“…Actuators 2023, 12, 350 9 of 29 published on this subject [42,50]. The material constants used for SMA actuator modeling were: length 1.8 m; cross-section (6 wires, 0.7 mm 2 each) 4.2 × 10 −6 m 2 ; martensite start (finish) temperature Ms (Mf) 58 ( 5) °C; Austenite start (finish) temperature As (Af) 30 (85) °C; Clausius-Clapeyron coefficient 7 × 10 6 Pa/°C; maximum phase transformation strain 0.1045 m/m; Young's modulus of austenite (martensite) EA (EM) 52 (22) GPa; resistivity of austenite (martensite) 8.2 (7.6) × 10 −7 Ω × m; density 6450 kg/m 3 ; latent heat of phase transformation QPT 100 × 10 6 J/m 3 ; specific heat CP 320 J/kg/°C; convection coefficient 18 W/m 2 /°C [50]. Three parallel SMA wires (1.8 m in length) actuate each sliding rod, which means six wires are acting together.…”

“…In China, at the School of Aeronautical Science and Engineering, Beihang University, Beijing, the structural design and testing of an adaptive variable camber wing were realized in collaboration with researchers from the University of Leeds, UK [19]. Various studies related to this concept were also realized by researchers from the Military Technical Academy in Romania [20][21][22]. The Indian Institute of Technology Madras studied, from structural and aerodynamic perspectives, various wing configurations for morphing [23,24].…”