bluuebunny/crossref_metadata_2025_split huggingface dataset:
Whole-Body Balancing Criteria for Biped Robots in Sagittal Plane
Authors: Mummolo Carlotta , Peng William Z. , Kim Joo H. 
Published: November 2019

Abstract
In this work, the role of swing limb dynamics in the stabilization of legged systems is investigated. To quantify the contribution of arm swing during whole-body balancing, the balancing capability of a bipedal robotic platform is evaluated computationally during single and double foot contact for two configurations: arms fixed and arms free to move. The balancing capability with each arm configuration is evaluated by constructing its corresponding balance stability boundary, a threshold between balanced and falling states that includes all possible center of mass (COM) states that are balanced with respect to the specified arm and foot contact configuration. In this analysis, the bipedal robotic platform is modeled as a kinematic tree structure with floating-base dynamics in the sagittal plane. In addition to floating-base and joint-space dynamics, the complete COM-space dynamics of the system is established, including the formulation of the angular momentum (and its rate) of each rigid link, as well as a model of actuation dynamics based on motor characteristics. The comparison of the two balance stability regions yields both a quantitative measure of the enhancement in total balance capability and qualitative insights into the mechanism by which arm swing leads to enhanced capability. The role of arm swing angular momentum is also analyzed from the robot’s experimental gait trajectories as a potential means of benchmarking controller performance.
Advancing Strategies to Reduce Worker Injury Risk on Mobile Mining Equipment
Authors: Mayton Alan G. , Pollard Jonisha P. , Nasarwanji Mahiyar F. , Kim Brian Y. 
Published: November 2019

Abstract
Improving mine worker safety and health is a key goal for the Pittsburgh Mining Research Division of the National Institute for Occupational Safety and Health (NIOSH). Opportunities to enhance the safety and health of mobile mining equipment operators through strategies to lower the risk of musculoskeletal disorders and traumatic injuries is an important element of the overall NIOSH mining research program. This paper reviews various emerging technologies that, if fully developed and implemented, could positively impact the health and safety of mine workers who operate mobile mining equipment. Those technologies showing potential for enhancing operator safety and health in the near future are addressed herein.
Optimum Design of a New Tuned Inerter Mass Damper (TIMD) Passive Vibration Control for Stochastically Motion-Excited Structures
Authors: Tai Wei-Che 
Published: November 2019

Abstract
The inerter that is referred to as a two-terminal device that provides resisting forces proportional to the relative accelerations between its two terminals has been widely applied in vibration control due to its mass amplification effect. In this paper, a new inerter-based damper is proposed to take advantage of the inerter, which consists of a rack-pinion inerter in conjunction with a tuned rotational inertia damper. Unlike any other inerter-based dampers, the rotational inertia damper is connected to the pinion of the inerter via a rotational spring and damper. As a result, the weight of the damper can be significantly reduced. The proposed damper is applied to single-degree-of-freedom primary structures and a two-degree-of-freedom structure and the H2 optimization is conducted to obtain the optimum tuning ratio and damping ratio analytically. When comparing the proposed damper with its counterpart reported in the literature, the proposed damper achieves 20% to 70% improvement when their weights are identical.
Billion Degree-of-Freedom Granular Dynamics Simulation on Commodity Hardware
Authors: Kelly Conlain , Olsen Nicholas , Negrut Dan 
Published: November 2019

Abstract
This study describes the implementation of a granular dynamics solver designed to run on Graphics Processing Units (GPUs). The discussion concentrates on how the Discrete Element Method (DEM) has been mapped onto the GPU architecture, the software design decisions involved in the process, and the optimizations allowed by those decisions. This solver, called Chrono::Granular, has been developed as a standalone library that can interface with other dynamics engines via triangle mesh co-simulation. A scaling analysis of the code presented herein demonstrates linear scaling with problem sizes of over two billion degrees of freedom and closing in on one billion bodies. We conclude with a study of hourglass (or hopper) mass discharge rate which compares the solver to experimental results and investigates a process for determining empirical coefficients of flow rate through simulation.
Upper Limb Rehabilitation and Mobility Assistance Using Robotic Devices: A Review
Authors: MajidiRad AmirHossein , Yihun Yimesker S. 
Published: November 2019

Abstract
This study is aimed at reviewing the various literature on the robot-based rehabilitation and the associated technical issues, augmentation, utilization, and safeties. During recent years, Biorobotics and Collaborative Robots have played a remarkable role to provide fast, accurate and efficient therapy and assistance. Most of these robots are equipped with various types of devices to control the intensity, duration, and precision of the training while some feedback systems have also been used to monitor the efficiency of the process and help physicians and therapists to furnish a high quality treatment. Haptic devices, Electromyography (EMG)/Electroencephalography (EEG) sensors, virtual environment and other interactive approaches have been utilized to optimize the process and to investigate different mental as well as physiological aspects. This review paper provides a comprehensive background on the human robot interactions and their outcomes in medical settings and potential research areas in the domain.
Substrate Optimization for Hybrid Manufacturing
Authors: Massoni Brandon R. , Campbell Matthew I. 
Published: November 2019

Abstract
While advances in metals additive manufacturing continue to make additive a viable option in more scenarios, these processes are generally slower and more expensive than subtractive methods, like machining. The combination of both additive and subtractive, often called hybrid manufacturing, can be used to get the benefits of both processes, while reducing cost. However, dividing a part into the most cost effective additive and subtractive features is often time-consuming and non-intuitive. In this paper, we present a new approach that optimizes the type, size, and position of a substrate within a part. The resulting hybrid manufacturing configuration enables engineers to reach the most cost-effective compromise between additive and machining. A fully implemented method has been developed and tested on several realistic engineering parts. The results are intuitively useful and push the state-of-the-art forward in generating hybrid manufacturing process plans.
Design, Modeling, and Optimization of a Hopping Robot Platform
Authors: Knaup Jacob W. , Aukes Daniel M. 
Published: November 2019

Abstract
Laminate devices have the potential to lower the cost and complexity of robots. Taking advantage of laminate materials’ flexibility, a high-performance jumping platform has been developed with the goal of optimizing jump ground clearance. Four simulations are compared in order to understand which dynamic model elements (leg flexibility, motor dynamics, contact, joint damping, etc.) must be included to accurately model jumping performance. The resulting simulations have been validated with experimental data gathered from a small set of physical leg prototypes spanning design considerations such as gear ratio and leg length, and one in particular was selected for the fidelity of performance trends against experimental results. This simulation has subsequently been used to predict the performance of new leg designs outside the initial design set. The design predicted to achieve the highest jump ground clearance was then built and tested as a demonstration of the usefulness of this simulation.
Multibody Simulation of an Electric Go-Kart: Influence of Power-Train’s Weight Distribution on Dynamic Performance
Authors: Anaya Jonathan Mikler , Calderon Santiago Camacho , Bradley Andrew , Gonzalez-Mancera Andres 
Published: November 2019

Abstract
A multibody model of an electric go-kart was developed in Msc-Adams Car software to simulate the vehicle’s dynamic performance. In contrast to an ICE kart, its electric counterpart bares an extra weight load accounted for the batteries and other powertrain components. The model is inspired on a prototype vehicle developed at Universidad de los Andes. The prototype was built on top of an ICE frame where a PMAC motor, controller, battery pack and the subsequent powertrain components were installed. A petrol-based Go-kart weight distribution was defined as baseline and several variants of the electric adaptation with different weight distributions were constructed. The main objective of the model is to evaluate different configurations and identify the ones that can give performance advantages. Step steer simulations ran at 40 km/h (64 mph) were analyzed to assess the dynamic performance of the vehicle for different configuration of the battery bank placement.
For most iterations of powertrain location, considerable differences in dynamic response were obtained and the handling balance was identified as Understeer contrary to a priori thoughs. Understeer gradient, weight distribution for both axles, trajectory among other results of interest were observed in the simulations. The model allowed to showcase the effect of redistribution of weight on the dynamic behavior in this specific application. Among the main consequences lies the fact that battery distribution can affect the lifting of the internal rear tire and the detriment in turning effectiveness.
An Archimedean Screw Based Energy Harvester for Oil Extraction, Water Injection, and Related Activities
Authors: Lin Rui , Jiang Boxi , Zuo Lei 
Published: November 2019

Abstract
This paper presents an Archimedean Screw Turbine (AST) based energy harvester designed to power wireless sensor system inside oil extraction or water injection wells. Numerical study has been carried out using CFD analysis to evaluate the performance of the harvester. Characteristics of the AST, including turbine length, blade pitch, and rotational speed were studied to determine the optimal geometry and operating conditions of the system. An AST prototype with a length of 85 mm and an outer diameter of 50 mm was fabricated through 3D printing and in-lab tests were conducted to validate the performance of the designed harvester. A maximum power output of 0.21 W was achieved under a constant pipe flow rate of 0.95 liter per second when an external resistive load of 10 Ω was connected to the harvester. Lastly, the experimental results were analyzed and compared to the CFD analysis.
Synthesis of Stephenson III Timed Curve Generators Using a Probabilistic Continuation Method
Authors: Baskar Aravind , Plecnik Mark 
Published: November 2019

Abstract
The kinematic synthesis equations of fairly simple planar linkage topologies are vastly nonlinear. This indicates that a large number of solutions exist, and hence a large number of design candidates might be present. Recent algorithms based in polynomial homotopy continuation have enabled the computation of entire solution sets that were previously not possible. These algorithms are based on a technique that stochastically accumulates finite roots and guarantees the exclusion of infinite roots. Here we apply the Cyclic Coefficient Parameter Continuation (CCPC) method to obtain for the first time the complete solution of a Stephenson III six-bar that traces a path and coordinates the angle of its input link along that path. Linkages of this type, called timed curve generators, are particularly useful for controlling the motion of an end effector point and influencing its transmission properties from a rotary input. For a numerically general version of the synthesis equations, we computed an approximately complete set of 1,017,708 solutions that divides into subsets of four according to the Stephenson III cognate structure. This numerically generic solution set essentially represents a design tool. It can be used in conjunction with a parameter homotopy to efficiently obtain all isolated roots of other systems of this same structure that correspond to a specific synthesis task. This is demonstrated with two example synthesis tasks.
A Lubrication Model of Elliptical Point Contact for Spiral Bevel Gears With Asymmetric Varying Velocity
Authors: Gopalakrishnan Srikumar C. , Lim Teik C. , Wang Yawen 
Published: November 2019

Abstract
In this work, elliptical contact is modeled in spiral bevel gear with a suitable ellipticity ratio. The elliptical point contact is modeled using constant velocity and varying velocity with side leakage. A loaded tooth contact analysis was carried out to determine the kinematic and gear mesh force developed during one mesh cycle. The kinematic parameters of the meshing gear pair, namely the contact cells, rolling velocity, sliding velocity and the load distribution in one mesh cycle are used in the elliptical point contact calculation to calculate the pressure and film thickness distribution. The effect of elliptical point contact and varying velocity on the pressure and film thickness distribution are studied. The time-varying contact parameters which are obtained from the tooth contact analysis are used in the tribological calculations. The effect of shaft misalignments on the elastohydrodynamic pressure distribution is also studied in this work.
A Systematic Rapid Creative Design Framework for Complex Mechanical Systems From Conceptual Design to 3D Virtual Simulation
Authors: Yu-Tong Li , Yu-Xin Wang 
Published: November 2019

Abstract
This paper presents a systematic rapid creative design framework for complex mechanisms to support creative conceptual design schemes’ generation and 3D virtual simulation. In conceptual design stage, a rule-based creative conceptual design system is constructed to expand conceptual design solution space through operating design rules related to functional requirements of design problems with graphic carriers. Compared with FBS models or catalogue-based matching approaches, the rule-based system can dig out more innovative conceptual design schemes including generalized mechanisms. Then a great number of conceptual design schemes generated in conceptual design are represented with symbolic schemes and identified into constituent basic mechanisms and their connections. To the constituent basic mechanisms, the object-oriented (OO) technology is applied to set up their 3D virtual solid models with encapsulated key feature parameters, which can be automatically modified by system’s database with the aid of the new defined classes. According to the OO solid models of constituent basic mechanisms and their connections, a 3D space layout algorithm considering the connections among the solid models is developed to determine the position of each constituent solid basic mechanism. Finally, an object-oriented based kinematic analysis method is pro-posed to carry out automatic kinematic analysis of the complex mechanisms related to the symbolic schemes. By means of the virtual-assembly approach and the kinematic data, all constituent components in the complex mechanisms are put onto the proper positions as they are assembled manually. In this way, the systematic design processes for complex mechanisms from creative conceptual design schemes’ generation, to 3D virtual solid design, layout de-sign, kinematic analysis, and virtual assembly and simulation are realized automatically. Based on the framework presented in this paper, rapid generating and evaluating innovative, excellent-performance schemes of complex mechanisms in 3D virtual prototype form are possible.
Control Strategy for Vehicle Lateral Dynamics Combining Torque Vectoring With Four Wheel Steering
Authors: Vignati Michele , Bravin Mauro , Sabbioni Edoardo 
Published: November 2019

Abstract
This paper presents a control strategy for multi-actuated vehicle for controlling the vehicle lateral dynamics. The controller tries to couple torque vectoring control, which is possible thanks to independent electric motors, with four wheels steering system by analyzing the vehicle behavior in the phase plane. A performance index is then defined to weight the two actuators intervention. The controller is tested in simulation environment where several typical maneuvers were simulated.
Performance Comparison of Inertial Measurement Units Fused With Odometry in Extended Kalman Filter for Dead-Reckoning Navigation
Authors: Carey Kevin , Abruzzo Benjamin , Harvie David P. , Korpela Christopher 
Published: November 2019

Abstract
This paper aims to aid robot and autonomous vehicle designers by providing a comparison between four different inertial measurement units (IMUs) which could be used to aid in vehicle navigation in a GPS-denied or inertial-only scenario. A differential-drive ground vehicle was designed to carry the multiple different IMUs, mounted coaxially, to enable direct comparison of performance in a planar environment. The experiments focused on the growth of pose error of the ground vehicle originating from the odometry senors and the IMUs. An extended Kalman Filter was developed to fuse the odometry and inertial measurements for this comparison. The four specific IMUs evaluated were: CNS 5000, Xsens 300, Microstrain GX5-35, and Phidgets 1044 and the ground truth for experiments was provided by an Optitrack motion capture system (MCS). Finally, metrics for choosing IMUs, merging cost and performance considerations, are proposed and discussed. While the CNS 5000 has the best objective error specifications, based on these metrics the Xsens 300 exhibits the best absolute performance while the Phidgets 1044 provides the best performance-per-dollar.
Computational Creativity via Assisted Variational Synthesis of Mechanisms Using Deep Generative Models
Authors: Deshpande Shrinath , Purwar Anurag 
Published: November 2019

Abstract
Computational methods for kinematic synthesis of mechanisms for motion generation problems require input in the form of precision positions. Given the highly non-linear nature of the problem, solutions to these methods are overly sensitive to the input — a small perturbation to even a single position of a given motion can change the topology and dimensions of the synthesized mechanisms drastically. Thus, the synthesis becomes a blind iterative process of maneuvering precision positions in the hope of finding good solutions. In this paper, we present a deep-learning based framework which manages the uncertain user input and provides the user with a higher level control of the design process. The framework also imputes the input with missing information required by the computational algorithms. The approach starts by learning the probability distribution of possible linkage parameters with a deep generative modeling technique, called Variational Auto Encoder (VAE). This facilitates capturing salient features of the user input and relating them with possible linkage parameters. Then, input samples resembling the inferred salient features are generated and fed to the computational methods of kinematic synthesis. The framework post-processes the solutions and presents the concepts to the user along with a handle to visualize the variants of each concept. We define this approach as Variational Synthesis of Mechanisms. In addition, we also present an alternate End-to-End deep neural network architecture for Variational Synthesis of linkages. This End-to-End architecture is a Conditional-VAE (C-VAE), which approximates the conditional distribution of linkage parameters with respect to coupler trajectory distribution. The outcome is a probability distribution of kinematic linkages for an unknown coupler path or motion. This framework functions as a bridge between the current state of the art theoretical and computational kinematic methods and machine learning to enable designers to create practical mechanism design solutions.
Prediction of Design Team Performance on a Conceptual Design Task Using an Automatable, Topic-Independent Analysis of Language Use
Authors: Cannon David M. , Edelman Jonathan 
Published: November 2019

Abstract
In this research, starting with an established metric called the Language Style Matching (LSM) measure [1] we show that some new LSM-based measures can predict team performance on an open-ended design task. We call these Style Entrainment Signal (SES) measures. Using them, two conversational patterns are newly identified, which we call “dwelling” and “forward-moving.” We show that a forward-moving pattern is associated with better-rated results produced by teams in 30-minute long conceptual design meetings with significant brainstorming activity. Through this, we gain insight into some of the interpersonal dynamics that contribute to a design team’s success. These results are founded on previous work in psycholinguistics, where it has been shown that analysis of language use can be used in several ways to predict a team’s performance on short, well-defined tasks. By expanding the research to more open-ended design tasks, and identifying two newly-measurable conversational patterns, we contribute back to psycholinguistic theory. The analysis developed for this work is automatable and topic-independent, and so it has potential to be applied widely.
Design of Non-Periodic Lattice Structures by Allocating Pre-Optimized Building Blocks
Authors: Choi Haejoon , Chung Baek Adrian Matias , Kim Namhum 
Published: November 2019

Abstract
The development of lattice design approaches using topology optimization to create complex lattice structures is the focus of ongoing research as the lattice structures show great potential throughout a wider range of research fields. Unfortunately, many of the methods suggested are often very difficult to industrialize due to their complexity and excessive computational costs in the design process. This paper proposes a novel framework of generating non-periodic lattice structures using topologically pre-optimized building blocks to improve the computational efficiency of the optimization process while maintaining the performance of the target structure and to make the process of obtaining optimal design more accessible for people with limited knowledge of topology optimization. The proposed method is comprised of two phases: the generation of a library holding optimized building blocks that can endure various loading conditions and the allocation of these building blocks at the proper location in the design space based on stress information obtained from the finite element analysis. Numerical examples are presented to show that the method is feasible and able to achieve reasonable performances, demonstrating its efficacy.