Study on the test load for the structural test of the flight-load condition of the external fuel tank for fixed-wing aircraft

In this study, for the purpose of conducting the structural tests for the verification of structural soundness of the flight-load conditions of the external fuel tank for the fixed-wing aircraft, the flight load acting on the external fuel tank was converted to test load and the suitability of the converted loads was verified. The loads imposed on the external fuel tank were expressed as the combination of the inertial load (based on the acceleration in the translational direction) and the tangential direction inertial load (based on the angular acceleration of the moment). To calculate the test load, the transfer function table was generated by calculating the shear load and moment based on the unit load. For this purpose, a transfer function table was established by dividing the external fuel tank into a few sections and calculating the shear load and moment generated by the unit shear load and unit moment in each section. In addition, the test load for each section was calculated by computing the established transfer function table and flight-load conditions. However, in actual structural tests, it is often not possible to impose a load in the same position as the point at which the shear load and moment are calculated. For this reason, the actual test-load positions had to be determined and the calculated test loads were redistributed to those positions. Then, the final test load plan was established by applying a whiffle tree to increase the efficiency of the test while also making it easier to apply the actuators. Finally, the suitability of the established test load plan was confirmed by comparison with the flight-load conditions.

Optimization of mechatronic drives motion laws for automated equipment

At present, when designing mechatronic cyclic drives the developer as a rule chooses the law of motion, specifying as input data, the cycle time and the amount of movement and often introducing restrictions, for example, on maximum acceleration in case of developing high-speed drives. However, this approach leads to an overestimation of the maximum drive power and, as a result, a significant increase in energy consumption. In this paper it is shown that by choosing a rational law of motion of the drive at the stage of equipment design, it is possible to achieve a sufficiently effective optimization according to various criteria. The efficiency of optimization of different motion laws of cycle drives according to various criteria is analyzed. The dependences between the maximum instantaneous power, the amount of movement, the speed and energy consumption are established and graphically presented confirming the effectiveness of the rational choice of the law of motion parameters under an inertial load. At the same time, it is shown that when synthesizing the law of motion, it is necessary to take into account the maximum possible number of parameters so that the improvement of some parameters does not lead to a decrease in other parameters.

Coded Control of a Sectional Electroelastic Engine for Nanomechatronics Systems

This work determines the coded control of a sectional electroelastic engine at the elastic–inertial load for nanomechatronics systems. The expressions of the mechanical and adjustment characteristics of a sectional electroelastic engine are obtained using the equations of the electroelasticity and the mechanical load. A sectional electroelastic engine is applied for coded control of nanodisplacement as a digital-to-analog converter. The transfer function and the transient characteristics of a sectional electroelastic engine at elastic–inertial load are received for nanomechatronics systems.

A fluid-structure interaction analysis of the human aortic arch under inertial load

Presented is an investigation into the use of numerical methods for modelling the effects of inertial load on the human cardiovascular system. An anatomically correct geometry was developed based on three-dimensional computed tomography (CT) data and independent meshes were created for the solid and fluid regimes. These domains were simulated using independent solvers and subsequently coupled using an intermediate data transfer alogrithm. At the inlet of the arch, a pulsatile velocity boundary condition was enforced replicating the cardiac cycle. Time invariant, resistive boundary conditions were used at all outlets and a linear isotropic constitutive model was used for tissue response. Verification was conducted by comparing simulation results at standard earth gravity (9.81 m/s²) with published values for velocity, mass flow rate, deformation, and qualitative flow behaviour. The presented fluid-structure interaction (FSI) model shows strong agreement with accepted normal values. Inertial load was then applied along the longitudinal axis of the arch in multiples of standard gravity to a maximum of 8+Gz. This load increased arch flow velocities, and reduced mass flow in the ascending brachiocephalic and carotid arteries. Blood flow from the arch to the upper body and brain ceased near 8+Gz. Although the presented results are preliminary, the feasibility of such an analysis has been successfully demonstrated.

A fluid-structure interaction analysis of the human aortic arch under inertial load

Presented is an investigation into the use of numerical methods for modelling the effects of inertial load on the human cardiovascular system. An anatomically correct geometry was developed based on three-dimensional computed tomography (CT) data and independent meshes were created for the solid and fluid regimes. These domains were simulated using independent solvers and subsequently coupled using an intermediate data transfer alogrithm. At the inlet of the arch, a pulsatile velocity boundary condition was enforced replicating the cardiac cycle. Time invariant, resistive boundary conditions were used at all outlets and a linear isotropic constitutive model was used for tissue response. Verification was conducted by comparing simulation results at standard earth gravity (9.81 m/s²) with published values for velocity, mass flow rate, deformation, and qualitative flow behaviour. The presented fluid-structure interaction (FSI) model shows strong agreement with accepted normal values. Inertial load was then applied along the longitudinal axis of the arch in multiples of standard gravity to a maximum of 8+Gz. This load increased arch flow velocities, and reduced mass flow in the ascending brachiocephalic and carotid arteries. Blood flow from the arch to the upper body and brain ceased near 8+Gz. Although the presented results are preliminary, the feasibility of such an analysis has been successfully demonstrated.

An Experimental Test Bench for Cable-Driven Transmission

Cable-driven transmissions are used widely in robotic applications. However, design variables and parameters of this kind of transmission remain under study, both analytically and experimentally. In this paper, an experimental test bench to evaluate the behavior of medium-low power pulley-cable transmissions is presented. The design of the test bench allows manipulating variables such as dimensions, external load, speed, and cable tension. The system consists mainly of a brushless direct current (DC) motor, two load cells to measure the mechanical reactive force in the motor, two dismountable pulleys, two drums, a perforated disk, and several masses that provide the load and the inertial load, and electronic modules to control the speed and position of the pulley. Special attention was paid to the calibration of the load cells, focused in compensating the effect of creep. Validation tests were carried out in order to evaluate the device design. Next, pilot experiments were performed to estimate the friction behavior in the transmission. Preliminary results suggest that the friction in the transmission is largely governed by the friction behavior of the bearings.