bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of Diffuser Vane Solidity on Performance of a Multistage Bowl Pump
Authors: Cooper Paul , Hosangadi Ashvin 
Published: November 2019

Abstract
The performance of a mixed-flow three-stage pump having a stage specific speed Ns = 2630 (rpm, gpm, ft) or nq = 53 (rpm, m3/s, m) — commonly known as a “bowl” pump — was improved by nearly five (5) percentage points by substantially increasing the number of vanes in the bowl-type diffuser. analysis showed a large field of unintended swirling flow emerging from the exit of the original diffuser. The solidity of the improved diffuser was much greater than conventional design practice would indicate. Yet this was needed to eliminate separation of the radially inward diffusing flow from the vanes as they effectively guide the fluid into the axial direction, thereby enabling the following stage(s) to generate the intended head and so achieve the intended efficiency. This apparently radical approach appears to be necessary in order to overcome the tendency of the circumferential velocity component of the flow from the impeller to increase as it is transported to the smaller radii of this radial inflow diffuser configuration.
Numerical and Experimental Investigation on the Influence of Blades Gap Flow on Axial Blood Pump Performance
Authors: Liu Guangmao , Jin Donghai , Wang Mengyu , Gui Xingmin 
Published: November 2019

Abstract
The axial blood pump body primarily contains the Inlet Guide Vane (IGV), Rotor Impeller (RI), Outlet Guide Vane (OGV) and pump casing. There must be gaps between rotor blade tip and pump casing or between OGV blade root and rotor hub for the impeller rotating in the pump. The flow characteristics inside an axial blood pump with different blade gaps were numerically simulated and analyzed. Hydraulics experiments were conducted to verify the numerical results. The results show that the pump efficiency decreased slowly when the OGV blade gap increased from 0.1 mm to 0.3 mm, but quickly when the rotor blade gap increased from 0.1 mm to 0.3 mm. The hydraulics characteristic results indicate that the pressure rise and efficiency are mainly influenced by the rotor blade gap. The OGV blade root gaps have little influence on the decrease of pressure rise and efficiency. The novel configuration with uneven blade gaps inside the pump result in improved hydraulics and hemolytic performance compared with the similarly sized configuration with even blade gaps.
IBM POWER9 Systems, Shock Simulation and Testing Validation
Authors: Alfoqaha Arshad , O’Connell Kevin , Campbell Eric 
Published: November 2019

Abstract
At IBM Systems, developing reliable and robust designs of supercomputers is critical to IBM’s vision and continuing its leadership in our industry. Shorter development cycle time, increasingly dense product designs, along with advanced design features create real challenges in predicting structural performance of servers, such as the recently refreshed IBM Cognitive Systems’ POWER9 portfolio of servers. Both 4U and 2U versions have DDR4 RDIMM’s, POWER9 HLGA processor modules, PCIe Gen3 and Gen4 slots, blowers, hard drives, and internal storage controller slots.
To meet IBM shipping standards to ensure POWER9 system’s reliability and design robustness, ANSYS Mechanical and LS-Dyna FEA models were developed and physical tests were conducted. The ability to apply accurate predictive engineering methods using simulation early in the design cycle predicted the structural performance of the servers and shortened its development time, reduced number of physical builds, and therefore, reduced development cost.
Dynamic Modelling and Diagnosis of Transverse Crack and Rotor/Stator Rub in a Flexible Rotor System
Authors: Vashisht Rajiv Kumar , Peng Qingjin 
Published: November 2019

Abstract
Due to unbalance present in a rotating machinery, fluctuating stresses are generated leading to the formation of transverse cracks in rotors. The cracks propagate with the passage of time and increase the amplitude of vibration. High vibration amplitudes can give rise to rotor/stator rubs. During the rubbing phase, the crack propagation gets enhanced due to inter-connected nature of these faults. If left unattended, these faults can cause the premature failure of machine components. Hence, there is a need to develop fault detection mechanisms based on the vibration response so that these faults can be diagnosed during initial stages. The effect of gravity and the presence of cracks significantly changes vibration characteristics of the rotor, which is thoroughly investigated in this research for a two-degrees-of-freedom Jeffcott rotor. It has been observed that during rubbing, high harmonics are excited. These harmonics are integer multiple of the rotor spin frequency. Similar type of the response is also observed due to the presence of a transverse rotor crack. It is difficult to distinguish the type of faults based on the steady state dynamic response only. Instead of working only on a steady state vibration response, the transient vibration response during coasting up of the rotor is considered. During coasting up of the rotor, high harmonics are excited for both the crack as well as rotor/stator rubbing. The excitation of higher harmonics starts at much earlier in the spectrogram of the vertical response for the cracked rotor compared to that of rubbing. This fact is used in the development of a fault diagnosis technique based on Short Time Fourier Transform of the vibration response. The proposed technique can efficiently distinguish different types of faults even if multiple faults coexist.
Improving the Stability of a Bulletproofed Vehicle Using Modified Suspension System
Authors: Sharaf A. M. , Yacoub M. I. , Elhefnawy A. A. 
Published: November 2019

Abstract
Bulletproof or high-class protected VIP vehicles are widely produced based on particular types of OEM (Original Equipment Manufacturer) commercial vehicles. The arising implications of increasing the level of protection of such vehicles have reflected several negative consequences on the vehicle directional stability. This is obviously true, since adding extra armored plates will increase both gross vehicle weight and the height of its center of gravity. Additionally, such vehicles are normally driven at higher speeds during critical evasive maneuvers. The proper selection of suitable suspension system in terms of spring, shock absorber and anti-roll bar for front and rear axles will contribute to the overall vehicle stability. This paper presents both theoretical and experimental investigation to upgrade the suspension system of a particular bulletproof vehicle in order to improve its stability during high-speed cornering maneuvers. For this purpose, six kits of nominated suspension systems have been tested in order to measure their stiffness and damping characteristics. Furthermore, for each suspension kit, the considered bulletproofed vehicle is fully assessed in CarSim® simulation environment. In-order to check the gained simulation results, typical field tests of the fully instrumented vehicle along with the modified suspension kit. From both simulation and field tests, a suitable kit for front and rear suspension system as well as braking system has been recommended not only to carry the additional weight of the heavy armored body but also to maintain the vehicle stability within their allowable limits.
Framework for Design From Manufacturing Data Mapping
Authors: Eddy Douglas , Krishnamurty Sundar , Grosse Ian , Steudel Mark , Shimazu Mike 
Published: November 2019

Abstract
Product development can be accelerated by utilizing increasingly available data from manufacturing and service. Despite data availability, few methods can integrate design to qualify product systems and facilitate the design of a product’s next generation. This work introduces a Design from Manufacturing Data Mapping (DfMDM) framework and process to enable development of predictive analytics techniques to learn final system test results. Salient features of the predictive analytics include introduction of an optimal composition of simulation models to more accurately predict system test results from digital twin data while determining which simulation models are most significant. The approach is demonstrated by a case study that accounts for parametric and model uncertainty. These initial results show that this approach to optimally compose simulation models can reduce error in system test result predictions at early product development stages.
Dynamics Analysis of the Deployment of Miura-Origami Sheets
Authors: Xia Yutong , Wang Kon-Well 
Published: November 2019

Abstract
Origami has emerged as a promising tool for the design of mechanical structures that can be folded into small volume and expanded to large structures, which enables the desirable features of compact storage and effective deployment. Most attention to date on origami deployment has been on its geometry, kinematics, and quasi-static mechanics, while the dynamics of deployment has not been systematically studied. On the other hand, deployment dynamics could be important in many applications, especially in high speed operation and low damping conditions. This research investigates the dynamic characteristics of the deploying process of origami structures through investigating a Miura-Ori sheet (Fig. 1(b, c)). In this study, we have utilized the stored energy in pre-deformed spring elements to actuate the deployment. We theoretically model and numerically analyze the deploying process of the origami sheet. Specifically, the sheet is modeled by bar-and-hinge blocks, in which the facet and crease stiffnesses are modeled to be related to the bar axial deformation and torsional motion at the creases. On the other hand, the structural inertia is modelled as mass points assigned at hinges. Numerical simulations show that, apart from axial contraction and expansion, the origami structure can exhibit transverse motion during the deploying process. Further investigation reveals that the transverse motion has close relationship with the controlled deploying rate. This research will pave the way for further analysis and applications of the dynamics of origami-based structures.
To Classify or Combine: The Effects of Idea Generation Mechanisms on the Novelty and Quantity of Ideas
Authors: Kirjavainen Senni , Hölttä-Otto Katja 
Published: November 2019

Abstract
Idea generation is an integral part of creative problem solving that happens in all businesses developing products — whether they were services or physical products. Idea generation methods have been studied against one another to create an understanding on how to produce most novel and innovative ideas or how to use certain mechanisms such as incubation or analogies in order to promote idea generation.
This paper presents a study comparing two idea generation mechanisms used as interventions during an alternate uses test. A group of 61 participants either classified or combined their ideas from the first round of ideation to come up with more ideas on a second round of idea generation. An outcome-based approach was used to evaluate the data and two metrics, quantity and novelty were used to evaluate the resulting ideas per group and round and unique ideas produced after the intervention.
The results suggest that at least when ideating alone, it is useful to stop and use some time to either classify or stop, observe and start combining the ideas already produced. Both have a positive effect on idea novelty, but classifying ideas results in significantly higher novelty scores over combining ideas. There was no difference in the novelty of unique ideas between the two groups, but both had a positive effect on novelty of unique ideas. Classifying ideas into categories produced significantly more unique ideas than combining ideas.
Dynamics and Control of Self-Standable Motorcycle
Authors: Hara Susumu , Nakagami Koki , Miyata Kikuko , Tsuchiya Mitsuo , Tsujii Eiichirou 
Published: November 2019

Abstract
This study discusses autonomous standing up from the parking mode and ensuring stability for low-speed driving of a novel motorcycle, named “MOTOROiD”. In 2017, Yamaha Motor Co., Ltd. released a motorcycle with a self-stabilizing mechanism, “MOTOROiD.” This prototype has a new rotary axis and can vary the position of the total center of gravity. This axis is called AMCES (Active Mass CEnter control System). This paper shows the modeling of MOTOROiD with parameters uncertainties for the control system design. The modeling is performed based on two different methods for established model verification: Lagrange’s equation method and the multibody dynamics. By using the established model, a unified control method for standing up from the parking mode and ensuring stability is designed by using a two-degree-of-freedom control system structure. The effectiveness of the modeling and control system design to the system with the variable parameter is verified by numerical simulations.
Quadrotor Singularity Free Modeling and Acrobatic Maneuvering
Authors: Liu Haowen , Yang Bingen 
Published: November 2019

Abstract
When an unmanned aerial vehicle (UAV) navigates reactively over an unknown land, it may encounter terrains that require aggressive maneuver to keep the designed coasting speed while staying on the path. During this execution of the aggressive maneuver, the UAV can experience singularity. In this article, a vertical loop aggressive maneuver performed by a quadrotor UAV is investigated. Due to the physical configuration of the quadrotor, the conventional modeling and tracking control method may not be desirable if certain requirements, such as fast coasting speed and sharp turns, are imposed. In this work, a new modeling and maneuver control method, which is called the controlled loop path following (CLPF) method is developed. As shown in numerical examples, the proposed singularity-free model and control method enables a quadrotor to be operated in aggressive maneuverability with features like automatic flipping and precise trajectory following.
Nonlinear Response Identification of an Asymmetric Bistable Harvester Excited at Different Bias Angles by Multiscale Entropy and Recurrence Plot
Authors: Wang Wei , Cao Junyi , Bowen Chris R. , Litak Grzegorz 
Published: November 2019

Abstract
Due to their high sensitivity to excitations with low intensity, bistable energy harvesting systems have received significant attention. In practical applications, it is difficult to achieve a bistable energy harvester (BEH) with a perfectly symmetric potential energy function. Moreover, gravity acts to exert a significant influence on the output response of a BEH oscillator when excited at different bias angles. Therefore, the experimental output voltage time-series of an asymmetric potential BEH are examined in this paper. The BEH studied here is composed of a cantilever beam, two piezoelectric layers at the root and two magnets at the end, and subjected to harmonic excitations at different bias angles. The energy harvesting system exhibited intra-well, periodic and chaotic snap-through vibrational patterns under different excitation frequencies at different bias angles. To better understand the multiple dynamic behaviors of the system corresponding to different power outputs, we identified the output voltage response by the methods of multiscale entropy and recurrence plots. Results indicate that periodic and chaotic vibrational patterns can be readily distinguished by the methods employed. Furthermore, it is demonstrated that the bias angle had a significant influence on the output power of the asymmetric potential BEH.
Kalman Filter Based Sensor Fusion for a Mobile Manipulator
Authors: Ubezio Barnaba , Sharma Shashank , Van der Meer Guglielmo , Taragna Michele 
Published: November 2019

Abstract
End-effector tracking for a mobile manipulator is achieved through Sensor Fusion techniques, implemented with a particular visual-inertial sensor suite and an Extended Kalman Filter algorithm. The suite is composed of an Optitrack motion capture system and a Honeywell HG4930 MEMS IMU, for which a further analysis on the mathematical noise model is reported. The filter is constructed in such a way that its complexity remains constant and independent of the visual algorithm, with the possibility of inserting additional sensors, to further improve the estimation accuracy. Experiments in real-time have been performed with the 12-DOF KUKA VALERI robot, extracting the position and the orientation of the end-effector and comparing their estimates with pure sensor measurements. Along with the physical results, issues related to calibration, working frequency and physical mounting are described.
Theoretical Validation of an Analytical Design Method for Beveloid Gears With Non-Parallel Non-Intersecting Axes
Authors: Marino Daniel , Bachmann Matthias , Binz Hansgeorg 
Published: November 2019

Abstract
An analytical calculation method was developed to determine the main gearing data for beveloid gears with non-parallel non-intersecting axes. To validate the method and identify its limits, a parameter study was to be conducted. A two-stage fractional factorial experimental design was therefore devised to deliberately vary the gearing parameters. For each gearing, an unloaded contact simulation was carried out using the position of the contact pattern, the transmission error and the predefined gear backlash as quality characteristics. The results of the simulation were subsequently classified in three evaluation categories.
Due to the generalizability of the method proposed, it can also be used for the design of other involute gearings. A modification of the equations revealed its applicability for spur gear pairs with no shaft angle and for crossed helical gear pairs with shaft angles up to 90°.
The results for the beveloid gear pairs investigated using a wide range of parameters as well as those for the cylindrical and crossed helical gear pairs proved the validity of the method. In the case of outliers in the evaluation, the causes were identified and corrective actions were presented.
Stress Field Guided Lattice Structure Design Based on Hexahedral Mesh
Authors: Liu Lingyun , Liao Yizhou , Gao Shuming 
Published: November 2019

Abstract
Lattice structures are promising for a wide range of applications. The development of additive manufacturing (AM) technology has made it possible to manufacture complex structures. However, designing the optimal lattices of complex solid models efficiently and automatically remains a challenge. Thus, we propose a novel stress-field-guided lattice design method to improve the mechanical properties of a lattice structure. Stress field is used to make the boundary struts of each cell of a lattice structure aligning to the principal stress direction while remaining conformal. Hierarchical cell templates are designed to reduce the computational burden of the cell optimization of a lattice structure. The proposed method is verified experimentally, and the experimental results prove the efficiency and validity of the proposed method.
Geometric Design of Pure Rolling Rack and Pinion Mechanisms
Authors: Chen Zhen , Zeng Ming , Fuentes-Aznar Alfonso 
Published: November 2019

Abstract
The study of different types of pure rolling rack and pinion mechanisms is presented. They are designed based on the active design of the meshing line to provide pure rolling for the whole cycle of meshing. Parametric equations for contact curves on the rack and pinion are determined by coordinate transformation of the meshing line equations. Moreover, parametric equations for the tooth surfaces of the rack and pinion of three types of meshing, including the convex-to-concave meshing, convex-to-plane meshing, and convex-to-convex meshing are derived according to the motion of generatrices along the calculated contact curves. Then, the basic design parameters are analyzed and formulas for calculation of the geometric size are given. The contact ratio of rack and pinion mechanisms can be designed to be higher than one, which satisfies the condition for the continuous transmission of gears. At last, a numerical simulation is conducted to validate the kinematic performance. This paper lays the foundation for further research of pure rolling rack and pinion mechanisms, their manufacture technology and strength design criterion.
How the Design of a 3D Printer Bridged Engineering Design Processes and the Agile Software Manifesto
Authors: Lindberg Steven , Campbell Matthew I. 
Published: November 2019

Abstract
Individual engineering design projects face different challenges depending on their scale. Instead of dealing with problems of complex multidisciplinary systems, small scale design must overcome issues of limited resources. The philosophy of agile software development has been highly successful in addressing similar issues in the software engineering realm over the past two decades. Through the design and prototyping of a low-budget desktop stereolithography printer, the application of agile principles to engineering design process is explored. The printer’s design is discussed in detail to provide examples of successes and failures when these agile principles are put into practice. The paper concludes with a discussion of how agile principles could be leveraged in engineering design. The approach taken in this paper is more of a longitudinal study of a single design process over a twelve-month period as opposed to rigorous experiments that engage multiple users in short design scenarios. Nonetheless, this case study demonstrates how the application of agile principles can inform, improve, and complement traditional engineering design processes.
Concurrent Topological Optimization of a Wheel and Brake Caliper Assembly
Authors: Gobbi Massimiliano , Previati Giorgio , Ballo Federico 
Published: November 2019

Abstract
The paper deals with the topological optimization of a wheel and brake caliper assembly. In this system, the design of each components is influenced by the actual shape of the other component. In fact, a conflict exists in the room requirements of the two components. In the design process, therefore, not only the material distribution of the two bodies has to be optimized, but also the design space has to be divided in most effective way.
The design of the wheel and brake caliper assembly can be seen as a special class of topological optimization problem. Such problem of concurrent topological optimization of two components sharing part of the design space has been already addressed by the authors in previous papers under the restriction that the two bodies have the same mesh in the shared part of the domain. In this paper, a novel development of the presented optimization algorithm is described. The algorithm is modified in order to allow the concurrent optimization of two bodies with different meshes in the common part of the domain. This new development allows the methodology to be applied to any real problem with arbitrarily complex geometry. The application to the case of the wheel and brake assembly is shown.