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The purpose of this paper is to analyze the aerodynamic improvements obtained in a wing section with a NACA 0018 airfoil manufactured using the fused deposition modeling (FDM) technique with regard to a smooth surface made by milling. The creation of micro-riblets on the surface of the airfoil, due to the deposition of the material layer by layer, improves the general aerodynamic performance of the parts, provided that the riblets are parallel to the flow line. The incidence of the thickness of the thread deposited in each layer – to be the variable on which the geometry of the riblets is based – was studied.

The wing section was designed using 3D software. Three different models were designed by rapid prototyping, using additive and subtractive manufacturing. Two of the profiles were manufactured using FDM varying the thickness of the layer to be able to compare the aerodynamic improvements. The third model was manufactured using a subtractive rapid prototyping machine generating a smooth surface profile. These three models were tested inside the wind tunnel to be able to quantify the aerodynamic efficiency according to the geometry and the riblets size.

The manufacture of an aerodynamic profile using FDM provides, in addition to the lightness and the ability to design parts with complex geometries, an improvement in the aerodynamic efficiency of 10 per cent compared with profiles with a smooth surface.

With the aerodynamic advantage gained through the use of FDM positions, the additive manufacturing serves as an excellent alternative for the manufacture of lightweight aerodynamic parts, with low structural loading and with low Reynolds number (∼5·105). This technological advantage would be applied to the UAV (unmanned aerial vehicle) industry.

The study carried out in this article demonstrates that the use of FDM as a manufacture process of end-used parts that are subject to movement generates an additional advantage that had not been considered. The additive manufacturing allows us to directly manufacture riblets by creating the necessary surface so as to reduce the aerodynamic drag.

The purpose of this paper is to develop an integrated rotorcraft design and virtual manufacturing framework. The framework consists of two major sub‐frameworks which are e‐design and virtual manufacturing frameworks. This paper aims to describe the process of generating a specific framework for helicopter design and manufacturing in general, and a method for main rotor blade design.

The e‐design process integrates a pre‐conceptual, conceptual and preliminary design phases and includes many high accuracy physics‐based analysis tools and in‐house codes. The development of analysis programs and integration of flow data are discussed under the e‐design process. The virtual manufacturing process discusses physical three‐dimensional (3D) prototypes using rapid prototyping, virtual process simulation model development using Delmia Quest, virtual machine tool simulation and process‐based cost model. Vehicle geometry is modelled parametrically in computer‐aided 3D interactive application (CATIA) V5 to enable integration between the e‐design and virtual manufacturing processes, and then saved in Enovia SmartTeam which is commercial software for product data management (PDM). Data saved in Enovia SmartTeam are used as a database for the virtual manufacturing process.

The integration framework was constructed by using Model Center software. A multi‐disciplinary design optimization loop for rotor blade considering manufacturing factors is discussed to demonstrate the robustness and efficiency of the framework.

The manufacturing (practical factors) could be considered at an early stage of the rotor blades design.

The gap between theoretical (engineering design: aerodynamic, structural, dynamic, design, etc.) and practical aspects (manufacturing) is bridged through integrated product/process development framework. The modern concurrent engineering approach is addressed for helicopter rotor blade design throughout the case study.

To investigate the ProMetal 3D printing technique for its application to dies, for low volume hot forging of 7075 aluminum helicopter parts.

Thermo‐mechanical and tribological behavior of the ProMetal 3D printed tools were characterized by hot upset and ring tests. Finite element simulations of the test application were conducted using special purpose metal forming simulation software FORGE3. Results obtained from the tests along with finite element analysis were used to validate behavior of the printed dies during forging trials.

ProMetal‐printed materials exhibited relatively low thermal conductivity and high friction. Cavities were printed, machined and evaluated in hot forging trials. Dies exhibited substantial settling during the manufacturing (3D printing) process. Some collapse of dies was also observed at locations where forging pressures were high.

After initial plastic settling, the printed dies provide satisfactory part tolerance for die temperatures and pressures up to 338°C and 689 MPa, respectively. Low thermal conductivity observed indicate a potential to forge aluminum with cooler dies. Coating or secondary polishing is necessary to achieve acceptable surface finish for forging of aluminum.

This paper demonstrates a need in RP industry to methodically match capabilities of the rapid prototyping process to the needs of the intended application through the use of finite element method and some fundamental characterization.

The paper aims to report the development of an Unmanned Aerial Vehicle (UAV) Testbed Training Platform (TTP). The development is to enable users to safely fly and control the UAV in real time within a limited (yet unconstrained) virtually created environment. Thus, the paper introduces a hardware–virtual environment coupling concept, the Panda3D gaming engine utilization to develop the graphical user interface (GUI) and the 3D-flying environment, as well as the interfacing electronics that enables tracking, monitoring and mapping of real-time movement onto the virtual domain and vice verse.

The platform comprises a spring-shuttle assembly fixed to a heavy aluminium base. The spring supports a rotating platform (RP), which is intended to support UAVs. The RP yaw, pitch and roll are measured by an inertial measurement unit, its climb/descend is measured by a low cost infrared proximity sensor and its rotation is measured by a rotary optical encoder. The hardware is coupled to a virtual environment (VE), which was developed using the Panda3D gaming engine. The VE includes a GUI to generate, edit, load and save real-life environments. Hardware manoeuvres are reflected into the VE.

The prototype was proven effective in dynamically mapping and tracking the rotating platform movements in the virtual environment. This should not be confused with the hardware in loop approach, which requires the inclusion of a mathematical model of the hardware in a loop. The finding will provide future means of testing navigation and tracking algorithms.

The work is still new, and there is great room for improvement in many aspects. Here, this paper reports the concept and its technical implementation only.

In the literature, various testbeds were reported, and it is felt that there is still room to come up with a better design that enables UAV flying in safer and unlimited environments. This has many practical implications, particularly in testing control and navigation algorithms in hazardous fields.

The main social impact is to utilise the concept to develop systems that are capable of autonomous rescue mission navigation in disaster zones.

The authors are aware that various researchers have developed various testbeds, at different degrees of freedom. Similarly, the authors are also aware that researchers have used game engines to simulate mobile robots or sophisticated equipment (like the VICON Motion Capture System) to measure to perform complex manoeuvres. However, the cost of this kind of equipment is very high, autonomous movements are planned in restricted environments and tested systems are only autonomous in certain setups. However, the idea of mapping the dynamics of an avatar flying object onto a 3D-VE is novel. To improve productivity and rapid prototyping, this paper proposes the use of commercially available game engines, such as the Panda3D, to create virtual environments.

Fluids management may be defined as the routeing and confinement of fluids, often under extremes of temperature, pressure and working environment. One of the most critical areas of this technology is the supply and transfer of liquids in aerospace fuel systems. Development of fluids management components for aerospace applications is driven by the requirement for total system integrity within the constraints of cost, space, mass, service conditions and material properties. Designers are challenged to produce novel solutions involving 3D simulation and modelling, finite element analysis and rapid prototyping. Simultaneous engineering is now an integral part of the process and designers must be aware of the latest manufacturing techniques and materials, both metallic and non‐metallic. Final design optimization is confirmed by prototype evaluation, followed by rigorous qualification testing. Explores design concepts and introduces some fluids management components in widespread use today. Reviews recent helicopter and non‐metallic material developments and discusses the future of the technology.

A specially designed hydraulic power pack is providing the motive power to test landing and deck handling systems on the Royal Navy's newest helicopter, the EH101 Merlin, developed jointly by Westland Helicopters in the UK and Agusta of Italy.

The purpose of this paper is to characterize the material properties of carbon fiber polyamide composite (CFPC) used in a 3D rapid prototyping process based upon selective laser sintering (SLS) and demonstrate that the SLS process introduces a bias in the micro‐fiber orientation such that the CFPC solid is an orthotropic structural material.

Material coupons for tensile tests from each of the orthogonal planes are created using the SLS process. After tensile testing, the coupons are examined under scanning electron microscopy to verify the micro‐fiber orientation bias. A complex 3D structure developed utilizing the CFPC material is subjected to modal testing to extract the natural frequencies. These frequencies are compared to predictive numerical analysis results from computer‐aided engineering (CAE) software to validate the coupon test results.

This paper proves that the CFPC solid material is orthotropic after the SLS process and that the process itself creates bias in the micro‐fiber orientation. Predictions of natural frequencies from CAE software for a complex 3D structure created from CFPC are within 2 percent of the actual natural frequencies determined during modal testing.

The paper has determined the tensile material characteristics of solid CFPC correcting the original material data sheet information which lists the solid CFPC as isotropic with much stronger tensile characteristics. It has also provided evidence of the bias that SLS introduces to embedded micro‐fibers during the rapid‐prototyping process.

The paper deals with experimental work on determining the material characteristics of a relatively new composite material for which very little test data exists in literature. In particular, an original contribution is demonstration of the micro‐fiber orientation bias introduced by the SLS process.

Leading manufacturers and their suppliers have begun to reap the benefits of a radically new way of bringing products to market. As these company's new products — developed using a total product modelling approach — move out into the marketplace, it marks the realization of a fundamental change in new product development thinking first mooted in 1991.