bluuebunny/crossref_metadata_2025_split huggingface dataset:
Developing Training Tools for Clinicians in LICs: Using Hidden Markov Modeling to Study the Decision-Making Strategies of Expert and Novice Prosthetists
Authors: Saravanan Pratima , Walker Michael , Menold Jessica 
Published: November 2020

Abstract
Approximately, 40 million amputees reside in the rural parts of Low-Income Countries (LICs), and 95% of this population do not have proper access to prosthetic devices and rehabilitation services. A proper prosthetic prescription requires a clear understanding of the patient’s ambulation, goals, cultural and societal norms, locally available prosthetic materials, etc., which can be accomplished only by a local prosthetist. However, due to the lack of prosthetic schools and training centers in LICs, the rural parts lack well-trained amputee care providers. Hence there is a need to educate the prosthetists and prosthetic technicians in the LIC, specifically in the rural regions. To accomplish this, the current research proposes a decision-support tool to aid decision-making during prescription and educate prosthetists. A controlled study was conducted with expert and novice prosthetists to compare effective decision-making strategies. Results suggest that experts leverage distinct decision-making strategies when prescribing prosthetic and orthotic devices; in comparison, novices exhibited less consistent patterns of decision-making tendencies. By modeling the decision-making strategies of expert prosthetists, this work lays the foundation to develop an automated decision support tool to support decision-making for prosthetists in LICs, improving overall amputee care.
Only As Strong As the Strongest Link: The Impact of Individual Team Member Proficiency in Configuration Design
Authors: Brownell Ethan , Cagan Jonathan , Kotovsky Kenneth 
Published: November 2020

Abstract
Prior research has demonstrated how the average characteristics of a team impact team performance. Individual characteristics of team members and individual team member behavior have been largely ignored, especially in the context of engineering design. In this work, a behavioral study was conducted to uncover whether the most or least proficient member of a configuration design team had a larger impact on overall performance. It was found that a configuration design team is most dependent on the proficiency of its most proficient member and results suggest that replacing the most proficient member with an even more proficient member can be expected to have a more positive impact than replacing any other member with a higher proficiency member of the same change in proficiency. The most proficient member had a significant positive effect on how quickly the team reached performance thresholds and that the other members of the team were not found to have the same positive impact throughout the design study. Behavioral heuristics were found using hidden Markov modeling to capture the differences in behavior and design strategy between different proficiency members. Results show that high proficiency and low proficiency team members exhibit different behavior, with the most proficient member’s behavior leading to topologically simpler designs and other members adopting their designs, leading to the most proficient member driving the team design and team performance.
Novice Designers’ Approaches to Justifying User Requirements and Engineering Specifications
Authors: Loweth Robert P. , Daly Shanna R. , Sienko Kathleen H. , Hortop Amy , Strehl Elizabeth A. 
Published: November 2020

Abstract
User requirements and engineering specifications represent important criteria that engineering designers use to define their design problems and evaluate the suitability of their solution concepts. Novice designers frequently develop user requirements and engineering specifications as part of curricular design projects; however, few studies have explored how novice designers justify the user requirements and engineering specifications that they develop. This preliminary study analyzed the design reports of capstone design teams to determine how novice designer participants justified their user requirements and engineering specifications. Teams frequently used “Sponsor interactions” and “Perceptions of user needs” as justifications for user requirements but gathered limited data directly from users. As such, the user requirements developed by teams may have been based on team assumptions rather than actual user needs. Teams frequently used “Sponsor interactions,” “Technical research,” and “Prior work” as justifications for engineering specifications. However, teams also developed several engineering specifications without clear justifications. Our findings suggest that as novice designers develop their design skills, they may need scaffolding and support tools to guide the development of user requirements and engineering specifications that accurately reflect user needs.
A Novel Gripping System for Delivery of Packages via Unmanned Aerial Vehicles
Authors: Maroo Trigun Dinesh , Wright Andrew B. 
Published: November 2020

Abstract
An Unmanned Aerial Vehicle (UAV) can carry packages to locations that are unreachable by a ground vehicle using a gripper that can handle standard sized packages. This paper presents a UAV-mounted system for grasping corrugated boxes. The proposed gripping system uses two pairs of end effectors which are arranged perpendicular to each other. All four grippers are geared so that they can be actuated by a single control input. The mechanism is designed to handle position and orientation errors of the box relative to the gripper. The gripper was experimentally validated using a test box that was misaligned in position and orientation.
Examine the Bending Stiffness of Generalized Kresling Modules for Robotic Manipulation
Authors: Kaufmann Joshua , Li Suyi 
Published: November 2020

Abstract
Via analytical modeling and experimental validation, this study examines the bending stiffness adaptation of bistable origami modules based on generalized Kresling pattern. These modules, which are the building blocks of an octopus-inspired robotic manipulator, can create a reconfigurable articulation via switching between their stable states. In this way, the manipulator can exhibit pseudo-linkage kinematics with lower control requirements and improved motion accuracy compared to completely soft manipulators. A key to achieving this reconfigurable articulation is that the underlying Kresling modules must show a sufficient difference in bending stiffness between their stable states. Therefore, this study aims to use both a nonlinear bar-hinge model and experimental testing to uncover the correlation between the module bending stiffness and the corresponding origami designs. The results show that the Kresling origami module can indeed exhibit a significant change in bending stiffness because of the reorientation of its triangular facets. That is, at one stable state, these facets align close to parallel to the longitudinal axis of the cylindrical-shaped module, so the module bending stiffness is relatively high and dominated by the facet stretching. However, at the other stable states, the triangular facets are orientated close to perpendicular to the longitudinal axis, so the bending stiffness is low and dominated by crease folding. The results of this study will provide the necessary design insights for constructing a fully functional manipulator with the desired articulation behavior.
A Novel Single-Step Unconditionally Stable Numerical Integration Scheme With Tunable Algorithmic Dissipation
Authors: Zhang Huimin , Zhang Runsen , Zanoni Andrea , Masarati Pierangelo 
Published: November 2020

Abstract
A novel single-step time integration method is proposed for general dynamic problems. From linear spectral analysis, the new method with optimal parameters has second-order accuracy, unconditional stability, controllable algorithmic dissipation and zero-order overshoot in displacement and velocity. Comparison of the proposed method with several representative implicit methods shows that the new method has higher accuracy than the single-step generalized-α method, and also than the composite P∞-Bathe method when mild algorithmic dissipation is used. Besides, this method is spectrally identical to the linear two-step method, although being easier to use since it does not need additional start-up procedures. Its numerical properties are assessed through numerical examples, and the new method shows competitive performance for both linear and nonlinear problems.
Optimizing Support for Heat Dissipation in Additive Manufacturing
Authors: Wang Cunfu , Qian Xiaoping 
Published: November 2020

Abstract
The paper presents a formulation for support optimization to maximize heat dissipation in additive manufacturing. To simulate heat transfer from the part to the supports, a boundary-dependent heat flux is applied on the part/support interface. Since the density-based topology optimization does not involve explicit boundary, the heat flux is implicitly imposed through a domain integration of a Heaviside projected density gradient. As such, this formulation also supports simultaneous optimization of support and parts in additive manufacturing. Self-supporting supports are obtained by controlling the anisotropic thermal conductivity of the supports. Three different objective functions related to heat dissipation efficiency are investigated. Numerical examples are presented to demonstrate the validity and efficiency of the proposed approach.
An Optimization Method for the Static Balancing of Manipulators Using Springs
Authors: Wang Jieyu , Kong Xianwen 
Published: November 2020

Abstract
This paper discusses a novel optimization method to design statically balanced manipulators. Only springs are used to balance the manipulators composed of revolute (R) joints. Since the total potential energy of the system is constant when statically balanced, the sum of squared differences between the two potential energy when giving different random values of joint variables is set as the objective function. Then the optimization tool of MATLAB is used to obtain the spring attachment points. The results show that for a 1-link manipulator mounted on an R joint, in addition to attaching the spring right above the R joint, the attachment point can have offset. It also indicates that an arbitrary spatial manipulator with n link, whose weight cannot be neglected, can be balanced using n springs. Using this method, the static balancing can be readily achieved, with multiple solutions.
A Sliding-Mode Control Algorithm to Enhance In-Hand Motion Capabilities
Authors: Kumar Rajesh , Mukherjee Joyjit , Mukherjee Sudipto 
Published: November 2020

Abstract
This paper reports a method for regulating the internal forces during in hand manipulation of an unknown shaped object with soft robotic fingers. It is known that for the case of multifingered manipulation, a part of the forces applied by the fingers result in the motion of the object, whereas the other part is considered to be an internal force. The internal forces do not result in the motion of the object but are used to improve the grip on the object. For an object with unknown shape, the internal forces are regulated to ensure that the object does not slip off during manipulation. It is shown that if soft fingers show bounded conformity and the finger-object interface does not have relative slip (or a bounded slip), then the relative angular velocity between the object and the fingertip frame in contact is bounded. The proof is used to define of a new metric of relative slip. The metric is used to design a sliding mode control algorithm. The robotic fingers are assumed to be under virtual rigidity constraint, that is, the distance between the fingers do not change. The control algorithm is attractive as it skirts requirement of information of the shape of the object or to solve optimization problems. The control algorithm developed controls the internal forces and does not require the knowledge of the shape of the object. The methodology is simulated for the case of one spherical object and one conical object.
Optimized Design and Performance Study of High Speed Five-Axis Machine Tools
Authors: Chan Tzu-Chi , Yang Jyun-Sian 
Published: November 2020

Abstract
With the development of machine tools trending toward high precision, intelligence, multi-axis, and high speed, the improvement of the processing performance and rigidity of the machine is considerably important.
The objective of this study is to design of a high-speed five-axis moving-column machine tool and perform structural analysis and optimization. We study the static and dynamic characteristics of the five-axis machine tool, design and improve the mechanical structure, and optimize the structural configuration of the machine. The entire machine structure is further analyzed and enhanced to improve its static and dynamic characteristics, including static rigidity, modal, transient, and spectral response characteristics. The static and dynamic characteristics of the machine structure directly affect the machine processing performance, and further affect the work piece precision machined by the tool. Through this study, the design technology for speed, accuracy, and surface roughness of the machine tool are further improved.
Compliant Interface in Component Mode Synthesis
Authors: Masarati Pierangelo , Darbas Fanny , Wander Israël 
Published: November 2020

Abstract
Substructuring, or component mode synthesis, requires components to share interface regions. When components modeled with rather different, often incompatible levels of refinement need to be connected, correctly defining the interfaces may be important. This work proposes the definition of the reduction of interface regions to the equivalent rigid-body motion which minimizes the strain energy in the structural component. The proposed formulation provides a natural and physically sound solution for the connection of detailed structural components within coarse, multi-rigid-body and 1D flexible models.
Natural Frequency Based Topology Optimization of an Aircraft Engine Support Frame
Authors: Warwick Braden T. , Mechefske Chris K. , Kim Il Yong 
Published: November 2020

Abstract
The multi-stage design space refinement (MSDSR) technique increases the likelihood of convergence of topology optimization (TO) with large volume fraction constraints. This work considers MSDSR TO of an aircraft engine support frame with a natural frequency-based objective function. The problem statement maximized the first natural frequency, effectively maximizing the stiffness to mass ratio of the frame. The problem statement considered natural frequency constraints, which eliminated all natural frequencies within 5% of the engine excitation frequency times a safety factor of two. The design space did not consider the initial geometry; therefore, allowing for the determination of the optimal stiffener location on the initial geometry. The results of this work increased the first natural frequency of the engine support frame by 25.9%, eliminated all natural frequencies within 11.3% of the engine excitation frequency, and added only 0.253 kg of mass to the frame. The results of this work further demonstrate the advantages of MSDSR TO and the impact that it can have on the aerospace industry. Specifically, the design space considered in this work allows for the structural reinforcement of a pre-existing design, which is easier to implement and easier to regulate than similar results from the literature.
Integrated Strategy for Automatic Lane-Changing Decision and Trajectory Planning in Dynamic Scenario
Authors: Ren Meng , Wu Guangqiang 
Published: November 2020

Abstract
Automatic lane change is a necessary part for autonomous driving. This paper proposes an integrated strategy for automatic lane-changing decision and trajectory planning in dynamic scenario. The Back Propagation Neural Network (BPNN) is used in decision-making layer, whose prediction accuracy of the discretionary lane-changing is 94.22%. The planning layer determines the adjustable range of the average vehicle speed based on the size of the “lane-changing demand”, which is obtained based on the data of hidden layer in neural network, and then dynamically optimizes the lane-changing curve according to the vehicle speed and the current scenario. In order to verify the rationality of the proposed lane-changing architecture, simulation experiments based on a driving simulator is performed. The experiments show that the vehicle’s maximum lateral acceleration under the proposed lane-changing trajectory at a speed of 70km/h is about 0.1g, which means the vehicle has better comfort during lane-changing. At the same time, the proposed lane-changing trajectory is more in line with the human driver’s lane-changing trajectory compared with that of other planning strategy. Meanwhile, the planning strategy can also support the lane-changing trajectory planning on a curved road.
Comparison of Soft Curved Crease Surrogate Hinges
Authors: Klett Yves , Middendorf Peter , Muhs Fabian , Tachi Tomohiro 
Published: November 2020

Abstract
The use of compliant hinges as integral elements of origami-based and origami-inspired structures can provide significant benefits compared to other hinge concepts, namely ease of integration, durability and tunable stiffness, range and target positioning of the hinge. So far, mostly classical straight-crease constructions have been used for the application of such hinges. Curved-crease geometries impose new constraints on the application of compliant elements in the crease region due to the implicit surface curvature in every non-flat folding state. This paper introduces a new, simple surrogate hinge based on angled slash arrays, and compares their behavior to classical lamina-emergent surrogate hinges.
Temperature Control to Increase Inter-Layer Bonding Strength in Fused Deposition Modelling
Authors: Kumrai-Woodruff Raoul , Wang Qing 
Published: November 2020

Abstract
Fused Deposition Modelling (FDM) provides opportunities for new development in numerous areas. Z-directional anisotropic strength caused by weak inter-layer bonding has been recognized as the reason for limited industry adoption of FDM. This paper aims to investigate increasing the Z-directional strength of Acrylonitrile Butadiene Styrene (ABS) using a temperature controlled print environment. The ambient temperature during printing was increased to reduce heat transfer from the print, thereby encouraging more polymer chain inter-diffusion between layers. Dogbone specimens were printed at ambient print temperatures between 24.8°C and 71.2°C and tensile tests were performed. A thermal camera was used to identify heat loss in the FDM process. Ultimate tensile strength was found to increase by a maximum of 104% compared to open enclosure printing. A stylus profiler and scanning electron microscopy were used to compare the quality of the inter-layer bonds, suggesting that additional polymer inter-diffusion occurred at hotter ambient temperatures. A weak positive relationship was found between ambient air temperature and inter-layer part strength. Further experimentation could provide scope to determine an ideal ambient print temperature that is likely to be dependent on print settings and the printer used.
The Influence of Heat Exchanges on Friction in Robotic Joints: Theoretical Modelling, Identification and Experiments
Authors: Pagani Roberto , Legnani Giovanni , Incerti Giovanni , Beschi Manuel , Tiboni Monica 
Published: November 2020

Abstract
This paper presents a model that describes the effect of heat exchange on dynamic friction in the joints of an industrial robot. As concern the modeling of friction as a function of the rotation speed of the joint, a third degree polynomial is used. The coefficients of the polynomial, which depends on the temperature, are estimated by means of a suitable identification procedure. The proposed technique is simple to implement and economically convenient. Experimental tests have shown that the method here proposed, despite its simplicity, can estimate with good reliability the variations of friction that occur during the operation of an industrial robot due to thermal effects. Possible fields of application are the improvement of the friction compensation algorithms used for robot control systems and the prediction of energy consumption.
Design Science Meets Data Science: Curating Large Design Datasets for Engineered Artifacts
Authors: Ramnath Satchit , Haghighi Payam , Ma Jiachen , Shah Jami J. , Detwiler Duane 
Published: November 2020

Abstract
Machine learning is opening up new ways of optimizing designs, but it requires large data sets for training and verification. The primary focus of this paper is to explain the trade-offs between generating a large data set and the level of idealization required to automate the process of generating such a data set. This paper discusses the efforts in curating a large CAD data set with the desired variety and validity of automotive body structures. A method to incorporate constraint networks to filter invalid designs, prior to the start of model generation is explained. Since the geometric configurations and characteristics need to be correlated to performance (structural integrity), the paper also demonstrates automated workflows to perform finite element analysis on 3D CAD models generated. Key simulation results can then be associated with CAD geometry and fed to the machine learning algorithms. With the increase in computing power and network speed, such datasets could assist in generating better designs, which could potentially be obtained by a combination of existing ones, or might provide insights into completely new design concepts meeting or exceeding the performance requirements. The approach is explained using the hood frame as an example, but the same can be adopted to other design components.
3D Additive Lattice Topology Optimization: A Unit Cell Design Approach
Authors: Hanks Bradley , Frecker Mary 
Published: November 2020

Abstract
Non-stochastic lattice structures are patterned after the unit cell topology and are of interest to the research and design communities for improving stiffness to weight ratios and/or metamaterial design. While additive manufacturing (AM) increases design freedom, it remains difficult to design or select an appropriate unit cell topology. In this work, a ground structure topology optimization approach is developed for unit cell design. Using a multi-objective evolutionary algorithm, this framework incorporates a library of different objectives, constraints, and penalties. The Additive Lattice Topology Optimization (ALTO) approach generates novel lattice structures for AM from the selected design objectives. A key purpose of this framework is incorporating AM process considerations into the optimization through objectives, constraints, and penalty functions for improved manufacturability. Two case studies presented in this work demonstrate ALTO’s ability to generate novel lattice structures with specific functionality while accounting for AM process constraints for laser powder bed fusion. Case Study 1 is an example of generating a lattice structure for heat sink applications. Case Study 2 demonstrates creation of three novel lattices with different stiffness properties, each with the same volume fraction. Using ground structure topology optimization and incorporating AM process considerations, ALTO is a unique approach for improved lattice structure design.