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2021 International Conference on Advanced Technologies and Applications of Modern Industry, ATAMI 2021

作者： Li, Lingzhi Guo, Wenchao Yang, Huawei Mao, Shimin State Key Lab. of Comprehensive Technology on Automobile Vibration and Noise and Safety Control No.1 Xinhongqi Street Changchun130013 China School of Mechanical Engineering Xi'An Jiaotong University Xianning West Road 28 Xi'an710049 China

A novel tooth surface design method of face-hobbed spiral bevel gears is proposed, which utilizes a solid cutter without axis tilting through tool path control combining with optimized cutter blade profile to control tooth contact patterns and realize tooth lengthwise chamfering. Firstly, a gear tooth surface generating plan of tool path controlling actively is developed, the mathematical model of the tool path is built, and the equations are given in detail, the determination method of all control parameters is also described. Next, the tooth surface functions of generating gear and machined gear are established based on a mathematic model of the traditional cradle machine tool. Then, the machine setting is also given in concise equations. Finally, the tooth contact analysis is also conducted for a specific gear pair to validate the validity and the reasonability of the new tooth modification method. © Published under licence by IOP Publishing Ltd.

关键词： Machine tools

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A Numerical Modelling for Laser Powder-Bed Fusion of Ti-Alloy with a Hybrid Heat Source: An Investigation on Solidification and Microstructure Formation

SSRN

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SSRN 2022年

作者： Hasanabadi, Mahyar Shahabad, Shahriar Imani Keshavarzkermani, Ali Eybel, Roger Gerlich, Adrian Toyserkani, Ehsan Lab Department of Mechanical and Mechatronics Engineering University of Waterloo WaterlooONN2L 3G1 Canada Lab Department of Mechanical and Mechatronics Engineering University of Waterloo WaterlooONN2L 3G1 Canada Safran Landing Systems 574 Monarch Avenue AjaxONL1S 2G8 Canada Department of Mechanical and Mechatronics Engineering University of Waterloo WaterlooONN2L 3G1 Canada

Among metal Additive Manufacturing (AM) methods, Laser Powder-bed Fusion (LPBF), is a proven fabrication method to produce complex-shaped parts with tailored properties. To achieve the desired properties, proper LPBF modelling facilitates the understanding of the correlation between input process parameters and output microstructure. In this paper, a numerical heat transfer modelling with a novel hybrid volumetric heat source has been proposed to simulate the LPBF of metastable beta titanium alloy (Ti-5553). The developed hybrid model, provides a reliable estimation of temperature distribution and thermal variables (e.g., temperature gradient G and solidification rate R), for any location of the melt pools, during solidification. For the process parameters which provide conduction melting mode, the simulated results agree well with experimentally measured melt pool dimensions where the verified model can also predict grain morphology, grain growth direction, and dendrite size. An in-depth analysis of predicted G/R values at the solidification front reveals that the center of the melt pool has a higher preference for equiaxed grain structure formation, while columnar grains are always dominant at melt pool boundaries. In addition, the scanning speed parameter was found to have a stronger influence on thermal conditions compared to laser power. © 2022, The Authors. All rights reserved.

关键词： Titanium alloys

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Thermal Management of Large-Sized Lifepo4 Pouch Cell Using Simplified Mini-Channel Cold Plates

SSRN

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SSRN 2023年

作者： Kausthubharam Koorata, Poornesh Kumar Panchal, Satyam Department of Mechanical Engineering Seoul National University Seoul08826 Korea Republic of Electrochemical Energy System Design Lab Department of Mechanical Engineering National Institute of Technology Karnataka Surathkal Mangalore575 025 India Mechanical and Mechatronics Engineering Department University of Waterloo 200 University Avenue West WaterlooONN2L 3G1 Canada

An efficient, simplified mini-channel cooling plate-based thermal management system is presented for LiFePO4 pouch cell. The proposed design improves the uniformity in surface temperature difference by more than 100% compared to existing literature data on similar designs. The proposed coolant design is tested for temperature distribution and cooling efficiency parameters by varying the cooling fluid volume flow rate and inlet temperatures from 15ml/min to 150ml/min and 5°C to 35°C, respectively. The proposed design maintains the maximum temperature in the cell well below 40ºC even under a 4C discharge rate and a high coolant inlet temperature of 35ºC. Increasing the coolant temperature is observed to positively impact the temperature homogeneity in the pouch cell. Further, an increase in cooling liquid flow rate is observed to have a reduced impact on the maximum temperature reduction at all discharge rates. The proposed simple design can be scaled to modular packs of pouch cells. © 2023, The Authors. All rights reserved.

关键词： Flow patterns

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On the Process Optimization, Microstructure Evolution, and mechanical Properties of Cucrzr Produced by Laser Directed Energy Deposition

SSRN

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SSRN 2022年

作者： Zardoshtian, Ali Ansari, Mazyar Esmaeilzadeh, Reza Keshavarzkermai, Ali Jahed, Hamid Toyserkani, Ehsan Multi-Scale Additive Manufacturing Lab Department of Mechanical and Mechatronics Engineering University of Waterloo WaterlooONN2L 3G1 Canada Department of Mechanical & Mechatronics Engineering University of Waterloo 200 University Avenue West WaterlooONN2L 3G1 Canada

Laser Directed Energy Deposition (LDED) is a suitable manufacturing technology for processing CuCrZr alloy that has recently gained interest to be used in high heat flux applications due to its unique thermal properties. However, the low laser absorptivity of this alloy at the laser wavelength of 1060 nm and high thermal conductivity make it challenging to reach a successful deposition. This study reports a systematic investigation into the LDED processing of CuCrZr alloy. The effects of main process parameters, which are laser power, scanning speed, and powder feed rate on the geometry, microstructure, and microhardness of single tracks are studied. Process parameters are optimized to achieve acceptable track geometries that consists of proper bead shape and sufficient dilution as well as maximizing the deposition rate. Further, the results from the investigations on microstructure of the printed samples by optical microscopy, SEM, and EBSD methods show a realistic correlation between the microstructure and the process parameters. Laser power and a combined parameter of powder feed rate over scanning speed are found to play a key role in the grain structure morphology and nucleation. Finally, the microhardness results reveal a moderate transition of hardness from the top of the bead to the bottom of the melt pool for all samples. © 2022, The Authors. All rights reserved.

关键词： Microstructure

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A Constant Force Tracking Strategy for Complex Surface Robots Fused with NURBS Speed Planning and Teaching/Learning Mode

A Constant Force Tracking Strategy for Complex Surface Robot...

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WRC Symposium on Advanced Robotics and Automation (WRC SARA)

作者： Duan Jinjun Cui Kunkun Guo An Wang Lingyu BinYiming Wan Minhong Huang Qiulan School of Mechatronics Nanjing University of Aeronautics and Astronautics China School of Automation Southeast University China College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and Astronautics China Chinese Academy of Sciences Shenyang Institute of Automation China Zhejiang Lab Hangzhou China Control Theory and Control Egineering Zhejiang University

Compliance control technology is particularly im-portant in contact operations such as grinding and polishing, surface tracking, and medical diagnosis. The core technology achieves contact control of a constant force for complex heterogeneous surfaces. However, due to the unknown environmental stiffness/position and dynamic changes, there are some problems, such as poor position/force tracking accuracy and a low degree of complex surface fit. To solve the above problems, a piecewise trajectory planning algorithm based on speed controllable NURBS and a teaching and learning mode constant force tracking strategy based on position/force coordination planning are proposed in this paper. First, a NURBS segmented trajectory planning algorithm with controllable speed is proposed by combining the NURBS trajectory planning algorithm with the T-type speed interpolation algorithm, and constant force tracking control based on the FCPressNURBS instruction set is realized by combining the adaptive admittance control algorithm. Second, based on the concept of teaching and learning modes, the position/force tracking parameters are obtained by the compliant control method, and the learning ideas is used to optimize the constant force tracking trajectory of the robot. Finally, the algorithm is tested on the ROKAE xMate robot, and the results show that the proposed algorithm improves the constant force tracking accuracy of the robot to the complex contact surface in the heterogeneous environment and can realize the adaptive constant force tracking effect of the robot to the unknown environment.

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Virtual sensing of wheel direction from redundant sensors in aircraft ground-steering systems

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CEAS Aeronautical Journal 2022年第1期13卷 199-213页

作者： Dal Borgo, Mattia Elliott, Stephen J. Ghandchi Tehrani, Maryam Stothers, Ian M. Institute of Sound and Vibration Research University of Southampton SouthamptonSO17 1BJ United Kingdom Department of Mechanical Engineering KU Leuven Leuven3001 Belgium DMMS Lab Flanders Make Leuven3001 Belgium ENTEG Engineering and Technology Institute Groningen University of Groningen Groningen Netherlands Ultra Electronics Precision Control Systems St Johns Innovation Park CambridgeCB4 0DS United Kingdom

Many safety-critical control systems use multiple redundant sensors to estimate the same controlled signal. If the sensors were to operate perfectly, only a subset of them would need to be used for the estimation. In practice, however, the sensors are subject to uncertainty, minor or major faults and their operation may be nonlinear. It is thus important to reliably estimate the controlled signal under these conditions, and also to assess the degree of confidence with which each sensor should be treated. An example of such a control system is the ground-steering control system of an aircraft nose landing gear. A virtual sensing technique is commonly employed, which estimates the steering angle using the measurements of multiple remote displacement sensors. The wheel position is then calculated as a nonlinear function of these sensor outputs. This paper describes how a digital twin of the ground-steering system, in which the effects of uncertainties and faults can be systematically analysed and studied, is used to assess the accuracy and integrity of the steering angle estimation for a number of different estimation algorithms. Two of these algorithms are based on a least-squares approach, while another is a soft-computing technique based on fuzzy logic. These methods are investigated for several scenarios where model uncertainty, measurement noise and sensor faults are included. It is shown that the soft-computing approach is more robust than the least squares based methods under these conditions. © 2021, Deutsches Zentrum für Luft- und Raumfahrt e.V.

关键词： Wheels

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Thick 3D-Printed Hierarchical Li4Ti5O12@MOF anode and Grid-Lined micropores for High-Performance Lithium-Ion batteries

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Journal of Colloid and Interface Science 2025年 696卷 137883页

作者： Mwizerwa, Jean Pierre Li, Jie Nsengiyumva, Walter Li, Chen Xu, Kun Rasaki, Sefiu Abolaji Liu, Changyong School of Materials Science and Engineering Fujian University of Technology Fuzhou350118 China Additive Manufacturing Institute College of Mechatronics & Control Engineering Shenzhen University Shenzhen518060 China Fujian Provincial Key Laboratory of Terahertz Functional Devices and Intelligent Sensing School of Mechanical Engineering and Automation Fuzhou University Fuzhou China The Institute of Precision Instrument and Intelligent Measurement & Control Fuzhou University Fuzhou China Institute: Department of Chemical and Petroleum Engineering University of Calgary AlbertaT2N 1N4 Canada

Li4Ti5O12 (LTO) anode is a promising candidate for high-energy–density lithium-ion batteries (LIBs), but achieving high mass loading, a porous structure, and efficient ion transport remains a challenge. Herein, we present a high-mass-loading, hierarchically porous LTO anode with a conductive network and grid-lined micropores, embedded with a metal–organic framework (MOF) as both an electrode additive and surface protective layer. This novel structure is fabricated using extrusion-based three-dimensional (3D) printing technology. The self-standing framework provides mechanical stability and high conductivity, enabling a thick (316 μm) 3D-printed LTO@UiO-66-MOF (3D-LTO@U) anode with a mass loading of 11 mg/cm2. It delivers a high-rate capability of 161 mAh/g at 5C, an areal specific capacity of 5.37 mAh/cm2, and 78.9 % areal capacity retention after 150 cycles. Additionally, it achieves a high specific energy density of 382.35 Wh/kg. The UiO-66 MOF provides strong binding affinity, suppressing side reactions and enhancing Li-ion/electron transport within the 3D-printed interconnected channels. This improves active material utilization during charge and discharge. Furthermore, a 3D-printed full cell integrating a grid-lined 3D-LTO@U anode and a 3D-printed LiFePO4 cathode exhibits enhanced electrochemical performance. This work demonstrates an effective strategy for designing thick, high-mass-loading, and porous conductive network anodes for advanced LIBs. © 2025 Elsevier Inc.

关键词： Lithium-ion batteries

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Analysis of actuation characteristics of CuAlNiMn/Polyimide thin film shape memory alloy

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Materials Today: Proceedings 2021年 46卷 9580-9585页

作者： M. Geetha K. Dhanalakshmi S. Jayachandran I.A. Palani V. Sathish Kumar Department of Instrumentation and Control Engineering National Institute of Technology Tiruchirappalli 620021 India Mechatronics and Instrumentation Lab Discipline of Mechanical Engineering Indian Institute of Technology Indore 453331 India Mechanical Engineering Kongunadu College of Engineering and Technology Tiruchirappalli 621215 India

The article presents the study of the deformation of an SMA bimorph actuator during static heating. The thermomechanical behavior of thin film CuAlNiMn shape memory alloy (SMA) on polyimide substrate is analyzed using finite element method. The analysis is carried out for three different geometries to obtain the displacement when temperature is varied. The actuation characteristics of the SMA bimorph are studied through direct heating and joule heating techniques. The surface morphology and composition of the bimorph sample are obtained using the Scanning Electron Microscope (SEM). The numerical analysis of the thermomechanical behavior of a thin film CuAlNiMn SMA bimorph is carried out using the finite element method. The procedure is applied for a double-legged cantilever configuration of the bimorph to obtain the actuation in terms of displacement; by varying the temperature. The same is repeated for semi-circular and pentagon shapes of the bimorph to obtain the influence of area on the displacement. It is observed that SMA bimorph displaces with the rise in temperature and the magnitude of displacement increases with the increase in surface area of different geometries. The physical actuation characteristic of CuAlNiMn-polyamide bimorph is studied by thermal heating and electrical heating of the sample, which confirm the shape memory effect of the SMA and provide the displacement characteristics of the bimorph when applying an electrical current.

关键词： CuAlNiMn shape memory alloy Bimorph Static Plate heating Joule heating

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Real-Time Unified Trajectory Planning and Optimal control for Urban Autonomous Driving Under Static and Dynamic Obstacle Constraints

arXiv

引用

arXiv 2022年

作者： Dempster, Rowan Al-Sharman, Mohammad Rayside, Derek Melek, William The Department of Electrical and Computer Engineering University of Waterloo Canada The Department of Mechanical and Mechatronics Engineering University of Waterloo Canada The WATonomous lab University of Waterloo ONN2L3G1 Canada

Trajectory planning and control have historically been separated into two modules in automated driving stacks. Trajectory planning focuses on higher-level tasks like avoiding obstacles and staying on the road surface, whereas the controller tries its best to follow an ever changing reference trajectory. We argue that this separation is (1) flawed due to the mismatch between planned trajectories and what the controller can feasibly execute, and (2) unnecessary due to the flexibility of the model predictive control (MPC) paradigm. Instead, in this paper, we present a unified MPC-based trajectory planning and control scheme that guarantees feasibility with respect to road boundaries, the static and dynamic environment, and enforces passenger comfort constraints. The scheme is evaluated rigorously in a variety of scenarios focused on proving the effectiveness of the optimal control problem (OCP) design and real-time solution methods. The prototype code will be released at ***/WATonomous/control. © 2022, CC BY-NC-ND.

关键词： Model predictive control

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Fabrication of translucent graded dental crown using zirconia-yttrium multi-slurry tape casting 3D printer

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Journal of the mechanical Behavior of Biomedical Materials 2024年 152卷 106406页

作者： Romario, Yulius Shan Bhat, Chinmai Ramezani, Maziar Pasang, Tim Chen, Zhangwei Jiang, Cho-Pei Graduate Institute of Manufacturing Technology National Taipei University of Technology 1 Sec. 3 Zhongxiao E. Rd. Taipei10608 Taiwan High-value Biomaterials Research and Commercialization Center National Taipei University of Technology 1 Sec. 3 Zhongxiao E. Rd. Taipei10608 Taiwan Department of Mechanical Engineering Auckland University of Technology Auckland1010 New Zealand Department of Engineering Design Manufacturing and Management Systems Western Michigan University KalamazooMI4900-5200 United States Additive Manufacturing Institute Shenzhen University Shenzhen518060 China Guangdong Key Laboratory of Electromagnetic Control and Intelligent Robotics College of Mechatronics and Control Engineering Shenzhen University Shenzhen518060 China Department of Mechanical Engineering National Taipei University of Technology 1 Sec. 3 Zhongxiao E. Rd. Taipei10608 Taiwan

This paper aims to fabricate functionally graded dental crown using a multi-slurry tape casting additive manufacturing technology. The different luminescence of the dental crown was obtained with different composition of zirconia and yttria. Zirconia with tunable mechanical properties and translucency are obtained by adding 3, 3.5, 4, 4.5, and 5 mol% of yttrium oxide to zirconia powder. After obtaining the printable slurry with maximum solid loading, the green bodies are prepared using the in-house built high-speed multi-ceramic tape casting technology. They are later sintered with two-stage sintering method. After the successful fabrication, the mechanical properties and translucency of the specimens were evaluated with Vickers hardness, three-point bending and translucency parameter tests. Finally, an FGM tooth crown with five photocurable slurries is proposed to demonstrate the translucent gradient effect of sintered part. The solid loading of 80% zirconia and 20% resin delivered samples without any surface cracks. The shrinkage ratio analysis showed that the sintered sample dimension was reduced by 20%, 20%, and 23% along X, Y, and Z directions. The samples fabricated with 3% yttrium oxide to zirconia delivered excellent hardness (1687 HV) and flexural strength (650.6 MPa). However, the relative luminescence increased with increasing the yttrium oxide for 3–5 mol%. With the optimized process parameters, the proposed dental crown is fabricated and analyzed for their shrinkage ratio, mechanical, and translucency properties. The study proposes the potential of fabricating customized dental crown with gradient translucent appearance. © 2024

关键词： Zirconia

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