https://jmss.qut.ac.ir/ Mechanics of Smart Structures en daily 1 Sat, 21 Mar 2026 00:00:00 +0330 Sat, 21 Mar 2026 00:00:00 +0330 https://jmss.qut.ac.ir/article_738350.html In this paper, the energy absorption behavior of a hemispherical truss with a porous core geometry in two cases, honeycomb and triangular, is investigated numerically and experimentally. For this purpose, a hemispherical truss with a honeycomb geometry is fabricated by connecting metal wires of a certain length and diameter. To increase the accuracy and quality of the laboratory-produced sample, a polymer template is fabricated using a 3D printer and placed between two rigid plates in a universal testing machine. At the start of the test, the movable rigid plate slowly moves towards the stationary rigid plate at a constant speed of 2 mm/min. In this process, which is carried out quasi-statically, the phenomenon of collapse and plastic deformation will occur in the truss. Finite element analysis of the same process is performed with 4 different wire lengths, 4 different wire diameters, 3 different materials, and 2 different geometries using Abaqus software. The results of the analyses show that the structure with triangular cell geometry, a wire diameter of 6 mm, a wire length of 30 mm, and an aluminum wire material has the best energy absorption in the studied range. https://jmss.qut.ac.ir/article_738351.html Tank level control is a critical task in industrial and chemical processes, where the main objectives are to maintain the liquid level at a desired setpoint and to prevent fluid overflow. This paper presents the design and experimental implementation of a PID controller based on the internal model control approach for tank level regulation. In the proposed scheme, the process model is first identified using classical system identification methods. Then, disturbances affecting the control process are compensated by subtracting the output of the identified model from the measured process output through a feedforward path. Next, a two-tank experimental setup is designed and constructed, equipped with the required sensors, and the proposed controller is implemented on the system in the form of a PID control structure. The performance of the proposed controller is assessed under different reference level profiles and various outlet valve conditions. Laboratory results confirm the effectiveness of the proposed controller in the presence of external disturbances and measurement noise. https://jmss.qut.ac.ir/article_738352.html Delamination is one of the most critical failure mechanisms in multilayer composites, stemming from their low interlaminar fracture toughness. In this study, nonwoven glass fiber interlayers were employed in glass/epoxy composites to enhance Mode I fracture toughness. To this end, composite specimens were fabricated using three types of base fabrics (with areal weights of 200, 400, and 600 g/m²) and two types of interlayers (with areal weights of 150 and 300 g/m²).the double cantilever beam (DCB) test was conducted in accordance with the ASTM D5528 standard, and the critical strain energy release rate was calculated using three analytical approaches: Modified Beam Theory (MBT), Compliance Calibration (CC), and Modified Compliance Calibration (MCC).Statistical analysis of the results revealed that the coefficients of variation for the data obtained via the MBT, CC, and MCC methods were 10%, 30%, and 15%, respectively. Furthermore, a comparison of the results demonstrated favorable agreement and satisfactory accuracy among all three methods in determining Mode I fracture toughness, with the differences in the calculated GIC values assessed to be within a range of 20 to 30 percent. These findings underscore the high efficiency and reliability of these computational methodologies in evaluating the fracture properties of interlayer-reinforced composites. https://jmss.qut.ac.ir/article_738354.html Rehabilitation robots are advanced systems designed to assist injured individuals by providing targeted support and facilitating therapeutic exercises, thereby helping to improve physical functions following injuries or medical interventions. This study focuses on the modeling and controller design of a rehabilitation robot. In the modeling section, the robot is considered as a planar three-degree-of-freedom serial robot to enable the actuation of the hip, knee, and ankle joints. The dynamic model of the robot is derived using the Euler–Lagrange method. Furthermore, with the increasing emphasis on robot-assisted rehabilitation, the need for adaptive control systems to tailor treatment to the individual needs of patients has become critically important. Therefore, due to the variability and uncertainty of the robot parameters, an adaptive controller is employed. In addition, considering the presence of noise in sensor data and disturbances arising from the interaction between the robot and the patient, a high-gain observer is used to estimate the system state variables, and a disturbance observer is utilized to estimate and compensate for disturbance effects. The obtained results demonstrate that the designed control system is capable of tracking the reference input with an error of less than 0.05 radians. https://jmss.qut.ac.ir/article_742663.html Hyperthermia using magnetic nanoparticles offers a non‑invasive approach for prostate cancer treatment. Since invasive temperature measurement in tumors is challenging, computational models like Pennes bioheat transfer equation are required. The novelty lies in simultaneous investigation of magnetic and electric fields on fractional viscoelastic blood flow within a stenosed vessel not previously modeled. Using COMSOL, Navier‑Stokes, energy, and concentration equations were solved to examine effects of field amplitude/frequency, volume fraction (0.02, 0.04, 0.06), and particle diameter on velocity, temperature, and concentration. Results show increasing nanoparticle concentration or field amplitude enhances heat generation. Each unit increase in induced heat flux raises prostate temperature by 0.2 °C, enabling precise titration to therapeutic window (41–45 °C) while protecting adjacent tissues (rectum, urethra) from necrosis. Raising inlet velocity from 0.1 to 0.2 m/s increases wall shear stresses; at volume fraction 0.04, pressure drop across stenosis rises 25% relative to baselin. A serious hemodynamic alert for elderly cardiovascular patients, highlighting need for personalized dosing and monitoring. The proposed framework provides a predictive tool for personalized dosage and field optimization in prostate cancer hyperthermia. https://jmss.qut.ac.ir/article_742664.html Design for maintainability is a systematic and proactive approach that integrates operational and maintenance considerations into the early stages of designing complex products such as marine vessels. Studies indicate that applying design for maintainability principles has a decisive impact on both the economic efficiency and operational readiness of fleets. However, traditional ship design remains primarily focused on criteria such as speed, seakeeping, and stability, while neglecting the critical role of maintainability in maritime missions. This conceptual paper, based on a systematic synthesis of literature, standards, and ship design experience, presents an integrated framework of key principles. Through thematic analysis, five fundamental principles were identified: accessibility, standardisation, modularity, reliability, and condition monitoring. Potential implementation barriers, including system complexity, budgetary constraints, siloed design practices, and human factors, were discussed alongside technology driven solutions such as artificial intelligence, the Internet of Things, 3D printing, and digital twins. The interdependencies among the principles were also examined. This framework provides strategic guidance for designers and maintenance decision makers, though empirical validation remains a direction for future research. https://jmss.qut.ac.ir/article_742666.html Oil mist emissions from turbomachinery lubrication reservoirs cause lubricant loss, environmental contamination, varnish deposition, and operational safety concerns. This study investigates the localization and experimental performance of an oil mist coalescing cartridge filter through reverse engineering and techno-economic assessment. A localized prototype was designed using pleated glass microfiber media with an effective filtration area of 2.55m2, following structural and material characterization of an imported reference filter. Tests were conducted according to ISO 12500-1 and ISO 12500-3 at 20℃, relative humidity below 50%, and operating pressure of 7±0.1 bar(g), using a laser particle counter. Based on three independent trials, the localized filter achieved a separation efficiency of 99.95%±0.04% for 1 μm oil aerosols, clean-filter pressure drops of 0.01 MPa (100 mbar) and collapse pressure exceeding 10 bar(g). The prototype exhibited performance equivalent to the imported filter while reducing procurement costs by approximately 35%. Long-term saturation and drainage behavior were not investigated and should be addressed in future studies. https://jmss.qut.ac.ir/article_742667.html In this paper, fatigue life of a suspension lug for jointing a store to a special aircraft has been assessed. The lug is used for jointing a store (which is a fuel tank in this paper) to a training aircraft. Using the load factor exceedance data of this aircraft, the load spectrum of the lug in a flight envelope has been evaluated. Only the normal load factors has been considered for fatigue analysis, because the longitudinal load factor is small compared with the normal load factor, and the transverse load factor occurs only in maneuver phase. 10 times of each flight envelope has been considered as a loading block. Then using the rain-flow technique, Goodman criterion, Miner’s rule and the S-N curve of the materials, fatigue life of the lug has been predicted. The effect of selecting various materials for the lug on fatigue life has been evaluated. The results showed that using AISI 4340 steel – compared with other relevant materials in aeronautical structures – is more useful and gives suitable fatigue life. The fatigue lifetime of the lug prepared from AISI 4340 steel is 1250 flight hours and the inspection intervals for this specimen is 250 flight hours. https://jmss.qut.ac.ir/article_742668.html Auxetic structures have attracted considerable attention due to their unique mechanical response, stable deformation behavior, and high energy absorption capacity. This study investigates the quasi-static in-plane compressive performance of a base chiral structure and its innovative modified configurations. The mechanical properties of PLA+ were first determined through tensile testing of FDM-printed standard specimens. Three-dimensional models were then developed in SolidWorks and numerically analyzed in Abaqus. To enhance energy absorption performance, six novel geometrical configurations, including square-reinforced, central-reinforced, arched, rhombic, circular, and cross-shaped designs, were evaluated against the base structure. The results showed that the normalized specific energy absorption (SEA) values for the base, square, central-reinforced, arched, rhombic, circular, and cross-shaped structures were 22, 40.5, 42, 38.6, 38.2, 44.2, and 39.7, respectively. Among the examined configurations, the circular structure exhibited the best overall performance, achieving the highest SEA and the maximum mean crushing force (MCF) of 0.57, while the square configuration showed the lowest peak crushing force (PCF). These findings demonstrate that the proposed geometric modifications provide an effective strategy for simultaneously improving SEA and PCF in chiral auxetic structures.