2024 Onward
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Item Open Access Trajectory study of power inspection quadcopter based on Udwadia-Kalaba theory(Canadian Science Publishing, 2025-02-25) Chen, Guangqing; Ma, Hongchang; Zhou, Peng; Sun, Aiqin; Ma, YicongIn this study, the dynamic model of the quadrotor is constructed by introducing the Udwadia-Kalaba theory, and the Moore-Penrose inverse is used to simplify the dynamic equations during the modeling process, avoiding the complexity of the traditional Lagrangian calculation methods. By transforming the three jobs of quadrotor pitch, roll and yaw into independent motions in X-Y、X-Z and Y-Z planes respectively, a simpler way of 3D trajectory presentation is realized. The Udwadia-Kalaba equation is simulated by MATLAB software, and the simulation results show that the dynamic model based on the Udwadia-Kalaba theory has high accuracy and stability, and its trajectory error is within the allowable error tolerance of ±0.01, which is suitable for the dynamic modeling needs in many complex scenarios. In addition, the Udwadia-Kalaba theory is compared with the traditional PID control method and the emerging Deep Reinforcement Learning (DRL) method. The DRL method also shows relatively excellent trajectory error control capability, with the overall error fluctuation range being controlled within ±0.05, while the PID exhibits error fluctuation of about ±0.1 and insufficient robustness. The results provide a new reference in the control modeling of quadrotor UAVs on the one hand, and extend the application of Udwadia-Kalaba theory to the study of vehicle trajectories on the other.Item Open Access Coupling effect of parameters on critical speed and hunting frequency of the linearized railway bogie system(Canadian Science Publishing, 2025-02-14) Gao, Hongxing; Sun, Jianfeng; Pan, Weifang; Liang, Jiayi; Chen, XiaohaoCritical speed and hunting frequency are critical metrics for assessing running stability, with a significant impact on railway vehicle dynamic performance. Evaluating effects of vehicle parameters on these two metrics is important for the optimization of vehicle design. This study focuses on a rigid bogie with secondary suspension, for which a lateral dynamic model accounting for lateral displacement and yaw motion is developed. Analytical formulas for critical speed and hunting frequency were derived by using perturbation procedures, Newton method and some simplified treatments. Employing the analytical formulas, a comprehensive analysis of multi-parametric influences was carried out, yielding global sensitivity indices for critical speed and hunting frequency against various parameters. The results indicate that the derived analytical formulas align well with numerical calculations, providing a basis for preliminary vehicle design optimization. There exists a coupling interaction between different parameters for their effects on critical speed and hunting frequency, which indicates the necessity of total-order global sensitivity analysis. The equivalent wheel-rail contact conicity is identified as the most sensitive factor on both critical speed and hunting frequency, while the damping of yaw damper also significantly affects the hunting frequency.Item Open Access A Narrative Review on Dynamic Postural Stability and Neuromuscular Control of Balance(Canadian Science Publishing, 2025-03-21) Jasimi Zindashti, Niromand; Noamani, Alirereza; Vette, Albert H.; Rouhani, HosseinNeuromuscular impairments can significantly hinder an individual's ability to maintain balance and carry out daily activities. Understanding neuromuscular control mechanisms is critical for identifying impaired balance in the elderly and individuals with neuromuscular impairments. More specifically, being able to characterize the biomechanics of dynamic balance and the underlying neuromuscular control mechanisms is essential for identifying impairments, implementing targeted rehabilitation, and developing assistive technologies. Considering this significance, this paper reviews methodologies and findings associated with dynamic stability and the neuromuscular control mechanisms involved in dynamic postural stability. First, this review discusses two methods of quantifying dynamic stability, extrapolated center of mass and feasible stability region, and how they are used to assess stability in different postures. Next, characterizing the roles of the underlying neuromuscular control mechanisms and components involved in stabilizing human posture are discussed. The role of each component in this control system and their modeling in various postures are examined. Finally, this review discusses the potential of existing methods to characterize human dynamic stability and inform future studies. This re-view concludes by highlighting the need for continued research to improve our understanding of neuromuscular control mechanisms involved in postural stability and develop effective interventions for individuals with neuromuscular impairments.Item Open Access An Efficient Optimization Design Method for Centrifugal Compressor Blades(Canadian Science Publishing, 2024-12-19) Liu, Jisheng; Liu, Manxian; Liu, BeiyingIn order to improve the time-consuming problem of centrifugal impeller optimization design, an efficient optimization design method is proposed. A bionic evolutionary algorithm based on a multi-surrogate model is established, model management strategies and geometric properties of the sigmoid function are investigated, and the penalty mechanism of infeasible solutions is revealed, which finally increases the speed of iterations and improves the optimum solution of constraint optimization problem for centrifugal compressor blades. Combining multi-surrogate model evolutionary algorithm, surface parameterization method and CFD for aerodynamic optimization of blade shape, the optimization results shows that the isentropic efficiency increased by 1.9%, the mass flow rate increased by 4.61%, the total pressure ratio increased by 0.81%, and the computational time was reduced by 54.9%. The sigmoid-based multi-surrogate model evolution algorithm improves the isentropic efficiency by 1.19% and the total pressure ratio by 0.63% compared with the unconstrained multi-surrogate model evolution algorithm, while the sigmoid-based multi-surrogate model evolution algorithm improves the isentropic efficiency by 1.16% and the total pressure ratio by 0.55% compared with the feasible point dominance constrained multi-surrogate model evolution algorithm, verifying the efficiency of the sigmoid-based multi-surrogate model evolution algorithm.Item Open Access A Tractor Transmission Systems Vibration Fault Data Augmentation and Diagnosis Method Based on DCGAN(Canadian Science Publishing, 2025-01-30) Xu, Liyou; Dong, Haojie; Zhao, Sixia; Wu, Yiwei; Chen, XiaoliangThe actual production process is often faced with insufficient fault data, Traditional data augmentation algorithms are prone to problems such as overfitting and pattern collapse. To address the issues, a tractor transmission systems vibration fault data augmentation and diagnosis method based on deep convolutional generative adversarial network is proposed. First, the original vibration signal is converted to a time-frequency diagram, which serves as the input to the generative adversarial network. Subsequently, the Two Timescale Update Rule(TTUR) strategy and gradient penalty are applied to stabilize the training process of the generative adversarial network, and the self-attention mechanism is introduced to enhance the feature extraction capability of the generative adversarial network. Furthermore, an enhanced AlexNet based on the Convolutional Block Attention Module is developed to improve the diagnostic performance. The approach was verified using datasets from Case Western Reserve University (CWRU), Huazhong University of Science and Technology (HUST), and a laboratory gearbox dataset. Results show 99% diagnostic accuracy for CWRU, over 97.5% for the laboratory dataset, and 98% accuracy under a single condition for the HUST gear dataset, with accuracy exceeding 95.3% under other conditions. . This indicates the method improves diagnostic precision and model generalization under data scarcity.Item Open Access Study on residual stress effects to cracking in the injection molding product – A case study of CPVC male threaded adapter fittings with copper insert(Canadian Science Publishing, 2024-12-18) Vo, Doan Hung; Hoang, Van Thanh; Tsai, Hsi-Hsun; Liao, Yi-Ling; Chen, Sin-He; Liu, Jia-Wei; Liang, Jin-Wei; Tran, Minh ThongMetal/alloy insert threaded polymer fittings are currently being widely used due to their outstanding advantages due to the combination of mechanical properties between polymers and metals/alloys. However, research and literature on metal insert thread adapter fittings are still limited nowadays. This study focuses on CPVC male threaded adapters with copper insert and their cracking for the purpose of conducting an insert threaded fitting literature. Crackings are generated by residual stresses accumulating internally over time, unobservable immediately after creating products. This study has discovered cracking by experiment and reduced residual stress by optimizing process parameters via the Taguchi method and Mold - Insert temperature survey, based on the Moldex3D simulation model. Furthermore, dimensional accuracy is ensured through the warpage displacement assessment. These methods could assist manufacturers in getting pilot-run samples to determine the suitable process parameters, ensuring the longevity of CPVC male threaded adapters with copper insert in particular and piping systems in general.Item Open Access Tribological and Thermal Performance of Graphene-Enhanced Lithium-Based Greases: Impact of Concentration on Friction, Wear, and Stability(Canadian Science Publishing, 2025-03-18) Stefan-Henningsen, Ethan; Roberts, Nathan; Pereira, Gavin; Kiani, AmirkianooshIn this study, lithium-based greases enhanced with varying concentrations of graphene (0.5 wt%, 1 wt%, and 2 wt%) were evaluated for their tribological and thermal performance. The Four Ball Wear Test, thermal imaging, and thermogravimetric analysis (TGA) were used to assess the impact of graphene on friction reduction, wear resistance, and thermal stability. The 0.5 wt% graphene-enhanced grease demonstrated the most favorable results, with superior friction reduction, wear resistance, and consistent lubrication over time. This is attributed to the uniform dispersion of graphene, which promoted the formation of a stable tribo-film and enhanced thermal conductivity. At higher concentrations (1 wt% and 2 wt%), graphene agglomeration led to diminished tribological performance, with increased friction and faster thermal degradation. TGA results further confirmed the superior thermal stability of the 0.5 wt% sample, with delayed onset of decomposition compared to the other formulations. These findings suggest that a graphene concentration of 0.5 wt% is optimal for improving the overall performance of lithium-based greases, providing a balance between friction reduction, thermal stability, and wear resistance.Item Open Access Evaluating roof-mounted VAWT performance with CFD for various building shapes, boundary layer flows, and location scenarios(Canadian Science Publishing, 2025-01-04) Rezaei, Farshad; Paraschivoiu, MariusThe performance of a Vertical Axis Wind Turbine (VAWT) is investigated when placed at different positions on the roof, considering the building's interaction with wind under various terrain categories and changes in the building's shape. Computational Fluid Dynamics (CFD) simulations are used to model a two-blade Darrieus-type VAWT. The results indicate that placing the VAWT at different positions on the roof leads to variations in the Power Coefficient (CP). The findings revealed that placing the VAWT in the middle of the roof edge led to 45.1 % and 6.7% increase in the maximum CP compared to the isolated turbine in the uniform flow and positioning it at the front corner of the roof, respectively. By considering different velocity profiles associated with various terrain categories, it was found that terrain roughness plays a significant role in the power performance of roof-mounted VAWTs. The results show that maximum performance is achieved in low-roughness areas, such as coastal regions, while the maximum CP decreases in rougher terrains. Additionally, the results indicate that when the VAWT is placed on top of a dome, it generates 50.7% more power compared to when it is placed on top of a cubic building of the same height.Item Open Access Microneedle Arrays for Brain Drug Delivery: The Potential of Additive Manufacturing(Canadian Science Publishing, 2024-10-11) Razzaghi, Mahmood; Bakhtiari, Sanaz Soleymani Eil; Charest, Gabriel; Fortin, David; Akbari, MohsenFor a long time, the treatment of brain diseases has been a significant challenge. Drug delivery to the brain has recently become one of the most challenging problems for patients with severe forms of central nervous system (CNS) diseases. The blood-brain barrier (BBB) poses a significant challenge for drug delivery to the brain. While extensive efforts focus on finding materials to overcome the BBB for brain tumor treatment, it limits the penetration of chemotherapeutic drugs for the broader treatment of brain diseases. The oral method of drug administration has several drawbacks, such as the loss of drugs because of metabolism and gastrointestinal environmental issues. Besides, using the intravenous route to administer medicines has several disadvantages, including discomfort at the injection site, infection, bleeding, anxiety, and incompetence toward patients. Fabrication and development of microneedles (MNs) to overcome the drawbacks mentioned above of traditional drug delivery methods may be a viable alternative. Drug delivery using microneedle arrays (MNAs) has recently been shown to be an effective method for delivering drugs to the brain. Different fabricating methods like three-dimensional (3D) printing could be used for the fabrication of personalized drug delivery systems, like MNAs, with precise control over spatiotemporal drug distribution. This article presents a review of using MNAs for drug delivery to the brain.Item Open Access An End-Effector for Polishing Based on a Parallel Mechanism with 3-PSS + PS'(Canadian Science Publishing, 2024-10-25) Liu, Youyu; Zhou, Xiangxiang; Wei, Ping; Lu, Songsong; Noor, Abu Saleh AbdunTo enable a polishing tool to automatically adjust its posture and adapt to the surface of the workpiece, an end-effector based on a parallel mechanism with 3-PSS+PS (Prismatic-Spherical-Spherical + Prismatic-Sphere-pin) was designed by using the reverse adaptive working principle. Based on the spiral theory, the degrees of freedom (DOF) of the mobile platform in the parallel mechanism are analyzed, And its DOF are verified according to the modified G-K formula. According to the kinematic analysis, the relationship between the plunger movement distance and the grinding wheel spatial pose is determined. The polishing force function between the grinding wheel and workpiece is obtained according to the analysis of the spatial pose of the grinding wheel. The main structural dimensions of the model were determined, and the physical model was given. The simulation analysis of the designed structure is carried out, the results show that: The end-effector can realize 3-DOF motion. The maximum rotation angle of the grinding wheel around the x-axis and y-axis is 7.68°and 6.68°respectively, which meets the design requirements. Within the working range, without controlling the end of a manipulator, the grinding wheel can adaptively compensate the trajectory error,and for different materials 45 steel, HT-200, 6061, the polishing force fluctuation is within 2.56% after stable polishing, which is basically constant.Item Open Access HYBRID RAY-TRACING MODEL FOR SOLAR ENERGY ASSESSMENT AND ITS OPEN-SOURCE IMPLEMENTATION AS A SERVICE(Canadian Science Publishing, 2024-11-04) ur Rehman, Naveed; Uzair, MuhammadThe existing solar ray-tracing programs for evaluating energy collection are closed-source platform-dependent packages and therefore, their integration into other programs, and adaptability to modern technologies (e.g. cloud storage and computing), are either not possible or are extremely complicated. This paper develops a hybrid ray-tracing-based mathematical model for assessing the solar energy received by geometrical layouts. Then, the design of a “Software as a Service” (SaaS) architecture, accessible through Representational State Transfer Application Programming Interfaces (REST APIs), is presented. It is implemented in an open-source environment, available under a Creative Commons license. Validation is performed by comparing the results for two layouts (with and without obstacles and reflectors) with semi-analytical manual solutions. Finally, an application is demonstrated for optimization of the tilt angle of a booster mounted on the top of façade-integrated solar receiver. The service with its client program and examples from this paper, is available for free download.Item Open Access Design of a centrifugal linear vibrating feeder driven by an eccentric motor(Canadian Science Publishing, 2019-04-25) Niu, Ruikun; Hua, ZhuIn this paper, a novel linear vibrating feeder is designed that uses the centrifugal motion of an eccentric motor as the driving source. Firstly, the working principle of the linear vibrating feeder is theoretically analyzed and the dynamic model is established. Subsequently, a dynamic simulation of the system is carried out using the ANSYS software. The relationship between the displacement amplitude, vibration speed, and frequency of the linear vibrating feeder prototype is tested using a three-dimensional vibrometer, with an OT-10A copper terminal used to test the prototype. The experimental results indicate that, at a vibration frequency of 125 Hz, maximum vibration speeds of 1.23 mm/s and 1.70 mm/s are reached in the X- and Z-directions, respectively. The corresponding maximum amplitudes are 0.7 mm and 0.99 mm, and the material feeding speed reaches a maximum value of 123 mm/s. Compared with similar piezoelectric and electromagnetic vibrating feeders, the total weight of the prototype is reduced by a third, the noise is reduced by more than 20 dB, and the driving voltage is only 3.6 V. Hence, the performance of the linear vibrating feeder has been successfully demonstrated.Item Open Access Study on the temperature dissipation performance of brake pads with different surface patterns(Canadian Science Publishing, 2024-04-29) Wu, Gang; Tian, Chen; Liu, ZhiPengDrum brakes may failure due to overheating in the contact area during frequent braking. This research takes the honeycomb structure with excellent heat dissipation and strength as the biomimetic object, and processes different biomimetic patterns on the surface of the brake pad. Using a self-made drum brake test bench, the changes in braking duration and surface temperature of different biomimetic pattern brake pads under emergency braking and repeated braking tests at different braking intervals are studied. The experimental results indicate that the braking duration of patterned brake pad is 7.82%~11.8% shorter than that of normal brake pads. Although the temperature of normal brake pads is lower at the end of braking, as the heat dissipation cycle prolongs, patterned brake pads exhibit faster heat dissipation, with honeycomb patterns having better heat dissipation than circular and square patterns. Using the least squares method, it was calculated that when the braking cycles were greater than 10.3s, 12.0s, and 14.5s, the braking heat dissipation effect of honeycomb, circular, and square brake pads was better than that of normal brake pads. These results validate that honeycomb patterned brake pads can alleviate the occurrence of thermal degradation in drum brakes.Item Open Access Effect of tooth surface wear on dynamic characteristics of spur gear transmission system(Canadian Science Publishing, 2024-04-29) Zhao, Juan; Cheng, Hongchuan; Lu, Kaiwen; Liu, Songnian; Yang, ZhouThe meshing stiffness and system dynamic characteristics caused by gear wear fault are studied. Firstly, potential energy method was used to model and solve the meshing stiffness of gears and the effect of wear on the meshing stiffness and static transfer error was analyzed. A 6-dof spur gear dynamics model was established considering various nonlinear factors, and the dynamic responses of the spur gear system under various wear degrees were analyzed by using time domain, spectrum, phase plane and Poincare mapping. Finally, the visual test platform of the gear box is built, and the wear condition and dynamic response of the gear box under different wear cycles are analyzed. Results show that the meshing stiffness of gear decreases due to wear, and the meshing stiffness of double tooth decreases more than that of single tooth. In addition, the static transmission errors caused by wear changes periodically with meshing frequency. Wear causes the vibration response of gear system to become complex gradually, and the nonlinear of the system is enhanced, which changes from single period motion to quasi period motion. Results can provide theoretical support for gear wear reduction, life extension, vibration reduction and noise reduction and lubrication improvement.Item Open Access Closed-Loop Control of Surface Preparation for Metallizing Fiber-Reinforced Polymer Composites(Canadian Science Publishing, 2024-06-20) Shokri, Shiva; Sedigh, Pooria; Hojjati, Mehdi; Kwok, Tsz HoThis study introduces a novel approach to enhance the surface properties of fiber-reinforced polymer composites through thermal spray coatings, utilizing a metal mesh as an anchor to improve coating adhesion. A critical step in this process is achieving optimal exposure of the metal mesh by sandblasting prior to coating. To address this challenge, we propose a closed-loop control system designed to inspect and blast parts effectively. Our method leverages top-view microscope images as inputs, employing a convolutional neural network (CNN) to correlate these images with the corresponding exposure levels of the metal mesh, measured via a destructive method. Upon training, the CNN model accurately estimates the exposure level solely from the top-view images, facilitating real-time feedback to guide subsequent sandblasting operations. Unlike traditional manual inspection methods, which demand expertise and experience, our automated approach streamlines the inspection process using a cost-effective portable digital microscope. Experimental findings validate the efficacy of our method in successfully discerning surface preparation status with an accuracy rate of 95% and demonstrate its practical utility in closed-loop control. Our study not only offers a robust methodology for quantifying surface preparation data but also presents a significant advancement in automating the inspection process. Moreover, the broader implications of our approach extend to various manufacturing sectors, where defect detection and closed-loop control are crucial for optimizing production efficiency and product quality.Item Open Access Performance of a Savonius Vertical Axis Wind Turbine installed on a Forward Facing Step(Canadian Science Publishing, 2024-06-17) Rabiei, Arezoo; Paraschivoiu, MariusThis study investigates the effects of installing a Savonius turbine on a forward-facing step to increase the power efficiency. Since the flow is disturbed by the step, the turbine may benefit from the accelerated flow found on top of the step. The flow field is solved using Computational Fluid Dynamics in a 3D computational domain. The Finite Volume Method is used to solve the Reynolds Average Navier-Stokes governing equations and the SST k-ω turbulence equations. This simulation includes both rotating turbine and the step. The novelty of this work is to study this configuration with a power law wind velocity distribution as inlet velocity, which is more realistic in common applications, and to investigate a different turbine. The study shows that the Savonius turbine generates up to 73% more power when installed on a 5-meter step. However, in case of a very high step, or a different turbine no improvement has been observed.Item Open Access Autonomous Firefighting Using a Quadruped Robot(Canadian Science Publishing, 2024-05-03) Baird, Christopher; Nokleby, ScottThis paper presents the development of a proof-of-concept autonomous firefighting robot based on the Spot quadruped robot. Both the payload and software package for the autonomous detection, localization, and extinguishing of a small fire are discussed. A thermal camera is mounted to the front of Spot and a standard ABC fire extinguisher is mounted to the back. The thermal camera is used to autonomously detect fires and the fire extinguisher is used to put out a detected fire. The system was successfully tested at a local fire station in a controlled setting with actual fires. The results of this project have direct application in the area of autonomous first response in complex industrial environments and fire watch applications.Item Open Access Parametric Optimization in Drilling of Sisal- Glass Reinforced Epoxy Composites using Taguchi Grey Relational Analysis method(Canadian Science Publishing, 2024-05-23) Tamilvendan, D.; Ravikumar, A.R.; Thirumalai, RThis research work intends to study the effect of hybridization of glass and sisal fiber, stacking sequence, immersion medium and temperature on tensile properties and water absorption behavior of the composite. The sisal-glass fibre hybrid composites laminates are prepared using reinforced plain woven sisal fabric (unidirectional) and plainwoven glass fabric. In this research study, 27 experiments are conducted as per L27 orthogonal array. Five process parameters are selected and three responses are considered in this work. The drilling of the composite specimen is considered and the drilling process parameters such as speed, feed rate, drill diameter, material thickness and drill point angle are selected. The responses considered in this work are delamination factor, thrust force and Torque. Taguchi analysis is performed and the response table for means for the responses is determined and the most influencing parameter in the drilling of the composite specimen is analysed. The grey relational coefficients are computed and followed with the computation of the grey relational grade. The grey relational grades are calculated for determining the highest contributing parameter in the drilling of the sisal fibre and glass fibre reinforced hybrid composite specimen. The optimum drilling process parameters are ranked and the ranks presented represent the sequence of run resulting in optimum solutions.Item Open Access Low-Cost Two-Dimensional Digital Image Correlation System(Canadian Science Publishing, 2024-04-02) VanDyk, Randall; Simha, HariA low-cost Digital Image Correlation (DIC) system for measuring two-dimensional (2D) displacement fields is described. Using an off-the-shelf camera, lens; and open-source DIC analysis software, displacement fields in aluminum and steel dog-bone tensile specimens were measured. Correction for out-of-plane motion is used to obtain strains from the displacement fields.Proposed DIC strain measurement system is validated using conventional thin-film strain gauges for strains below 1%. Average strain measurements from the DIC system were found to be within 1 % of the measurement obtained using strain gauges.For strains between 1-10%, strain histories from the DIC systems displayed excellent correlation with strain measurements obtained using an extensometer.Item Open Access Sustainable Metal-infused Polymer Feedstock Compatible with Low-cost Metal Sinter-based 3D Printing(Canadian Science Publishing, 2024-03-19) Karimi, Naeim; Fayazfar, HaniyehAdditive manufacturing has been employed to fabricate metallic parts; however, prevalent techniques are expensive and energy-consuming. Therefore, fused deposition modeling (FDM) technique has grabbed the attention of researchers and industries. Despite the promising results, available materials for metal FDM 3D-printing are very limited. The current study presents the development of a novel metal-infused polymeric feedstock for FDM 3D-printing, consists of spiky-shaped recycled nickel powders and polylactic-acid (PLA) polymer matrix. A low-cost desktop 3D printer is employed to produce green parts; subsequently, debinding/sintering processes can be conducted to achieve a fully metallic part. The low-cost recycled nickel powder, that has been used in this study, is produced using the low-carbon footprint process, Mond process, with a significant application in production and recycling of nickel and iron-based batteries. Furthermore, PLA is chosen because it is bio-based and biodegradable with a lower carbon footprint in the carbon cycle than fossil-fuel-derived polymers. Therefore, the whole process is an ecofriendly cycle, stepping toward the sustainable and affordable production of metallic components. Regarding development of a novel feedstock material compatible with 3D-printing, it is important to understand its properties. So, the developed feedstock materials are rheologically and physico-mechanically analyzed to find the optimum filler concentration.