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Carbon fiber-reinforced composites represent a broadly utilized class of materials in aeronautical applications, due to their high-performance capability. The studied CFRP is manufactured from a 3K carbon biaxial fabric 0°/90° with high tensile resistance, reinforced with high-performance thermoset molding epoxy vinyl ester resin. The macroscale experimental characterization has constituted the subject of various studies, with the scope of assessing overall structural performance. This study, on the other hand, aims at evaluating the mesoscopic mechanical behavior of a single-ply CFRP, by utilizing tensile test specimens with an average experimental study area of only 3 cm2. The single-ply tensile testing was accomplished using a small scale custom-made uniaxial testing device, powered by a stepper motor, with measurements recorded by two 5-megapixel cameras of the DIC Q400 system, mounted on a Leica M125 digital stereo microscope. The single-ply testing results illustrated the orthotropic nature of the CFRP and turned out to be in close correlation with the multi-ply CFRP tensile and bending tests, resulting in a comprehensive material characterization. The results obtained for the multi-ply tensile and flexural characteristics are adequate in terms of CFRP expectations, having a satisfactory precision. The results have been evaluated using a broad experimental approach, consisting of the Dantec Q400 standard digital image correlation system, facilitating the determination of Poisson’s ratio, correlated with the measurements obtained from the INSTRON 8801 servo hydraulic testing system’s load cell, for a segment of the tensile and flexural characteristics determination. Finite element analyses were realized to reproduce the tensile and flexural test conditions, based on the experimentally determined stress–strain evolution of the material. The FEA results match very well with the experimental results, and thus will constitute the basis for further FEA analyses of aeronautic structures.

This paper presents a study undertaken following the collaboration between specialists in two multidisciplinary fields, namely engineering and medicine. It was aimed at solving a practical problem by developing of a handle for use in orthopedic surgery. Specific engineering tools, knowledge and processes and methods were used for accomplishing this task. Tailoring devices according to surgeons preferences for ensuring an ergonomic use is an important criterion alongside functional and sterilization requirements, cost and fabrication time, 3D printing representing a feasible manufacturing solution as this research proves. The article details the steps required to complete the final product: design and redesign, numerical analysis, prototypes manufacturing and testing. To perform the numerical analysis that highlights the device mechanical behavior, finite element method was used in assessing different handle designs.

Additively manufactured wrist–hand orthoses (3DP-WHOs) offer several advantages over traditional splints and casts, but their development based on a patient’s 3D scans currently requires advanced engineering skills, while also recording long manufacturing times as they are commonly built in a vertical position. A proposed alternative involves 3D printing the orthoses as a flat model base and then thermoforming them to fit the patient’s forearm. This manufacturing approach is faster, cost-effective and allows easier integration of flexible sensors as an example. However, it is unknown whether these flat-shaped 3DP-WHOs offer similar mechanical resistance as the 3D-printed hand-shaped orthoses, with a lack of research in this area being revealed by the literature review. To evaluate the mechanical properties of 3DP-WHOs produced using the two approaches, three-point bending tests and flexural fatigue tests were conducted. The results showed that both types of orthoses had similar stiffness up to 50 N, but the vertically built orthoses failed at a maximum load of 120 N, while the thermoformed orthoses could withstand up to 300 N with no damages observed. The integrity of the thermoformed orthoses was maintained after 2000 cycles at 0.5 Hz and ±2.5 mm displacement. It was observed that the minimum force occurring during fatigue tests was approximately −95 N. After 1100–1200 cycles, it reached −110 N and remained constant. The outcomes of this study are expected to enhance the trust that hand therapists, orthopedists, and patients have in using thermoformable 3DP-WHOs.

CT scans interpretation is no longer strictly related to the machine. They can be analysed with specialised software that allows for diagnosis, surgical and dental procedures planning. So, medical doctors can analyse and determine the step-by-step procedure in the actual phase with a computer. There are presented some real examples computed with Mimics software.Reference to this paper should be made as follows: Comaneanu, R.M., Tarcolea, M., Vlasceanu, D. and Cotrut, M.C. (2012) 'Virtual 3D reconstruction, diagnosis and surgical planning with Mimics software', Int.

Numerous clinical observations performed on patients who have achieved dental restorations on implants drew attention to the risk of immediate or late complications. The most common late complications are lost of implant components and fracture of implant. While loss of screw only produce patient discomfort, implant fracture lead to more serious complications and subsequent treatment is extremely difficult. The causes of these complications are static mechanical failure of the implant system and overloading of the assembly [1]. The main function of dental implants is to transfer the load to the surrounding biological tissues. Therefore, the first objective of functional design is to dissipate and distribute biomechanical loads, in order to optimize function on prosthesis built on implants.

Determining the dynamic properties in the frequency domain of aircraft structural elements is a very important aspect taken into account nowadays by aircraft manufacturers. One of the helicopters most exposed element to structural vibrations is the rotor blade, thus making its construction and the material choice a very important decision. Finite element methods can be used to assess the vibrational properties of such elements, in order to prove their airworthiness. The main objective of the article is to study how the use of different materials affects the structural behavior of the helicopter tail rotor blade, with regard to the frequencies at which these structures are prone to vibrate. The blade profile is the NACA0012 symmetric airfoil used on the IAR330 helicopter tail rotor blade and the main objective is to identify the best inner core material, while highlighting the importance of polymeric materials.

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