bluuebunny/crossref_metadata_2025 huggingface dataset:
Toward Standards-Based Generation of Reusable Life Cycle Inventory Data Models for Manufacturing Processes
Authors: Brundage Michael P. , Lechevalier David , Morris K. C.
Published: November 2018

The production stage of a product's life cycle can significantly contribute to its overall environmental impact. Estimates of environmental impact for a product are typically produced using life cycle assessment (LCA) methods. These methods rely on life cycle inventory (LCI) data containing impact estimates of manufacturing processes and other operations that contribute to a product's creation. The accuracy of LCI data is critical for quality assessments; however, these data are often insufficient in the types and varieties of manufacturing processes covered and are often only a coarse estimate of actual impacts. At the same time, much manufacturing research focuses on how to model, measure, assess, and reduce the environmental impacts of manufacturing processes. Recent standards emerging from ASTM International define a structured format for presenting these studies in a reusable way. In this paper, we investigate the potential for using the ASTM E3012-16 format to generate LCI datasets suitable to perform LCA by mapping from the ASTM standard into the widely adopted ecoSpold2 format. A process is presented for generating LCI datasets from ASTM models, and overlaps and gaps between the two standards are identified.
Entropy Generation Due to Heat and Mass Transfer in a Flow of Dissipative Elastic Fluid Through a Porous Medium
Authors: Afridi M. I. , Qasim M. , Makinde O. D.
Published: November 2018

This study examines the effects of viscous and porous dissipation on entropy generation in the viscoelastic fluid flow induced by a linearly stretching surface. Analysis of mass transfer is also performed. Consideration of rheological characteristics of viscoelastic fluid in the energy conservation law and entropy generation number in terms of viscous dissipation makes a striking difference in the energy equation and entropy generation number for Newtonian and viscoelastic fluid. This important concern which is yet not properly attended is also be examined in the present study. The dimensional governing equations are reduced to a set of self-similar differential equations. The energy and concentration equations are solved exactly by employing the Laplace transform technique. The obtained exact solutions of reduced set of governing equations are utilized to compute the entropy generation number. To analyze the impacts of flow parameter on velocity profile, temperature distribution, concentration profile, and entropy generation number inside the boundary layer, graphs are plotted and discussed physically. The permeability and viscoelastic parameters have strong influence on the entropy generation in the vicinity of stretching surface.
Computer-Aided Inspection Planning: A Multisensor High-Level Inspection Planning Strategy
Authors: Sadaoui Sif Eddine , Mehdi-Souzani Charyar , Lartigue Claire
Published: November 2018

Computer-aided inspection planning (CAIP) has gained significant research attention in the last years. So far, most CAIP systems have focused on the use of a touch probe mounted on a coordinate measuring machine (CMM). This article investigates multisensor measurement aiming to perform automatic and efficient inspection plans. High-level inspection planning, which deals with sequencing of measuring operations, is the main concern of inspection planning. This paper presents an automatic approach to generate inspection sequences by combining laser sensor and touch probe, and by giving preference to the measurement using the laser sensor if quality requirements are satisfied. The proposed approach consists of three steps. In the first step, recognition of inspection data from the computer-aided design (CAD) part model is carried out based on the concept of inspection feature (IF), and the extracted information is stored in a database. In the second step, a list of privileged scanner orientations is proposed by analyzing the accessibility of both sensors. In the third step, a sequence of operations is generated iteratively. For a given scanner orientation, the ability of the laser sensor is assessed according to an original process based on fuzzy logic model. If the laser sensor does not meet the ability requirements, touch probe ability is assessed. The proposed approach is implemented and tested on a part defined by its CAD model and specifications.
Dynamic Stress Analysis on Barrel Considering the Radial Effect of Propellant Gas Flow
Authors: Yu Qingbo , Yang Guolai
Published: November 2018

The stress response of an artillery barrel when fired is principally due to loading from gas pressure and contact force with the projectile. This paper reports a research project in which a dynamic model of a barrel and a projectile was established in order to investigate the stress response of an artillery barrel. Calculations of propellant gas pressure, in part determined by the position of the moving projectile, were carried out using user-defined subroutines developed in the abaqus/explicit software. Numerical simulations of the dynamic loading process of the barrel were carried out to examine the radial effects of gas pressures. Using this methodology, the evolution of barrel stress distributions was simulated, providing a visualized representation of the barrel's dynamic response. The calculated dynamic stress due to projectile contact alone can reach a peak value of 181 MPa, reflecting the significant effect of contact force on the barrel's dynamic response. Following this, the effect of propellant combustion on the dynamic response was explored, and the results obtained showed that higher initial temperatures produced more pronounced dynamic responses. Moreover, significant differences in stress distributions computed for the barrel revealed deficiencies in the static strength theory for evaluating the operating conditions, due in part to the omission of contact force and other dynamic effects. This paper proposes an alternative investigative approach for evaluating the dynamic stress response of barrels during the initial phases of the ballistics process, and provides information that should lead to updates and improvements of barrel strength theory, ultimately leading to better predictions of firing reliability and operator safety.
A Modified Active Anti-Disturbance Control for a Nonlinear CSTR Model
Authors: Dasgupta Sudeshna , Sadhu Smita , Ghoshal T. K.
Published: November 2018

Active Anti-Disturbance Control, which so far had reportedly been applied to linear plant models, has been extended in this work to cover control of nonlinear plant models. To accommodate nonlinear plants, an Internal Model Controller (IMC) and a Disturbance Observer (DOB) for nonlinear systems have been used innovatively in the design architecture. It is conjectured that the IMC approach would mitigate plant parameter perturbations whereas the DOB would take care of external disturbances together to conjugatively produce a more robust closed loop plant. To illustrate the proposed algorithm, viz., Modified Active Anti-Disturbance Control (MAADC), the proposed technique has been employed to control a nonlinear Continuous Stirred Tank Reactor (CSTR) system. It is shown that strong external disturbances and model uncertainties have been actively mitigated by using the proposed MAADC, indicating superior robustness compared to ordinary nonlinear IMC based control. Different set-point and disturbance conditions have been considered to characterize the algorithm.
Utilization of ADAS for Improving Idle Stop-and-Go Control
Authors: Jeong Kwangwoo , Lee Hoon , Lee Jaihyun , Yoo Sanghoon , Lee Byungho , Kim Sejun
Published: November 2018

Idle Stop and Go (ISG), also known as Automatic Engine Stop/Start, has been widely implemented in production vehicles as one of the “Eco” functions that save fuel, and the application has been promoted to meet stringent fuel economy regulations throughout the world. However, the vibration and the hesitation caused by engine stop and restart often discourage the usage. Because a conventional ISG system usually restarts the engine when it sees the brake pedal release, the driver may perceive a delay in immediate vehicle launch. Furthermore, there are some driving conditions where engine on/off is undesirable or unnecessary. A quick stop-and-go situation such as making a complete stop at a stop sign is one of the conditions where ISG would be inappropriate, and in those cases, ISG may irritate the driver or even end up increasing fuel consumption with too frequent engine stop/start.

In order to mitigate aforementioned issues, a utilization of Advanced Driver Assistance System (ADAS) is proposed. With the surrounding traffic information obtained from the ADAS module, ISG control algorithm is able to determine when to turn on or off the engine prior to driver’s input. The applications demonstrated in this paper include the following usage examples: The ISG control logic monitors the movement of the vehicle in front and restarts the engine out of ISG mode before brake release, which eliminates the delay in the following vehicle launch. By employing traffic sign recognition and vehicle location info, the control logic is also able to inhibit engine off when the vehicle stops at stop signs which will avoid unwanted ISG activation.

In this paper, the advanced ISG control logic is introduced, and the real-world vehicle test results are provided with the description of prototype vehicle configuration.
Multi-Objective Optimal Design of Four-Parameter PID Controls
Authors: Sardahi Yousef , Boker Almuatazbellah
Published: November 2018

This paper presents a multi-objective optimal PID (Proportional-Integral-Derivative) controller with the derivative filter factor as the fourth design parameter. The complete design of the PID controller should involve tuning four parameters instead of three. However, most of the research papers consider only three parameters. The fourth parameter, the filter factor, is assigned to a default value or selected experimentally. In all cases, the choice of this factor filter will alter the closed-loop response’s characteristics that were assumed before inserting the filter in the control loop. Therefore in this study, we include the filter factor in the decision variable space from the early stage of the control system design. Also, we formulate the design problem as a multi-objective optimization problem in order to show all the trade-offs among the system speed of response, percentage overshoot, sensitivity to external load disturbances, and sensitivity to noises impacting the measurements as the four parameters of the PID control are tuned. The optimal trade-offs solutions are then introduced to the decision-maker who can choose any one of them.
Helicopter Swashplate Design and Analysis Using Semi Compliant Mechanism
Authors: Tekes Ayse , Khalid Adeel , Giannakakos Niko , Bryant Alexander
Published: November 2018

The swashplate of a model helicopter consists of stationary and rotating plates separated by ball bearings. This mechanism enables the swashplate to tilt in all directions and move vertically as one unit. The lower stationary plate is mounted on the main rotor mast and connected to the cyclic and collective controls by a series of pushrods. There are similar pushrods known as pitch links connected to the upper rotating plate. These pitch links are connected to the pitch horns and control the pitch of individual blades. In this study, the pitch links of the model helicopter are replaced by a semi compliant mechanism. This mechanism is directly connected to the pitch horns to control the pitch of the individual blades. The actuation of the bars can be achieved by using high torque stepper or servo motors. These precise low and high amplitude outputs are specifically required for the cyclic and collective controls of the helicopter swashplate. The compliant swashplate mechanism can be fabricated as a single piece using an injection molding technique or by 3D printing. The mechanism is modeled by two similar vector loops in two different planes. The mathematical model of the plate motion and the forces on the mechanism links are developed and simulated using MATLAB and Simulink, and initial results are discussed in this paper. This mechanism would be applied to the helicopter directional control where the plate in the pitch-roll mechanism would serve as the swash plate of the helicopter.
Electrochemical Model-Based Aging Characterization of Lithium-Ion Battery Cell in Electrified Vehicles
Authors: Huang Meng , Kumar Mrinal
Published: November 2018

Lithium-ion battery cycle- and calendar-life remain to be one of the greatest uncertainties for the advanced energy storage systems. Accurate characterization of battery aging has been crucial for battery state-of-health (SOH) estimation and the remaining useful life (RUL) prediction. The formation-and-growth of the solid-electrolyte interphase (SEI) has been widely recognized as one of the most prominent battery degradation mechanisms. It consumes the cyclable lithium within the cell and ultimately leads to the capacity fade which cannot be measured directly onboard. This study evaluates the multi-scale multi-physics battery models and their respective aging mechanisms as well as the corresponding characterization metrics. Then the reduced order single particle model (SPM) is selected in this study, given its parametric dependence on both electrochemical and physical parameters as well as its compatibility to the available measurements in vehicle for aging characterization. nLi, the total moles of cyclable lithium within the cell, is identified as a valid aging parameter that can effectively characterize the capacity fade through the interpretation of experimental aging data. This study also investigates into the potentially optimal testing profile and the sufficient amount of data required for the accurate aging characterization. Then the method of brute force nearest neighbor search (NNS) is applied to derive the long-term evolution trend of the aging parameter nLi, which can serve as a key benchmark for validating the in-vehicle implementable algorithms for battery state-of-health (SOH) estimation and as an important foundation for predicting the remaining useful life (RUL) of battery.
Distributed Coordination of a Multi-Agent System With Intermittent Communication: A Switched Systems Approach
Authors: Zegers Federico M. , Chen Hsi-Yuan , Deptula Patryk , Dixon Warren E.
Published: November 2018

In this paper, a novel switched systems approach is taken to enable the distributed coordination of a multi-agent system with intermittent communication. A mobile information service provider switches between various (follower) agents in the network to provide them with state feedback when they are within close proximity. The follower agents do not have navigational sensors but are still proven to converge to a desired goal through open-loop control with intermittent error correction by the leader. A switched systems stability analysis is performed to determine the maximum dwell-time the mobile information service provider can intermittently communicate information to the agents to ensure convergence to the desired goal. Simulation results are included to demonstrate the development.
Control With Optimal Energy Regeneration in Robot Manipulators Driven by Brushless DC Motors
Authors: Ghorbanpour Amin , Richter Hanz
Published: November 2018

In this work, simultaneous energy regeneration and motion control for robot manipulators with brushless motors is considered. The robot has a number of semi-active joints connected to ultracapacitors, while the remaining joints are fully-active, powered from constant-voltage power supplies. A three-phase inverter is used to apply voltage to each motor, and the space vector pulse width modulation technique is used to generate voltage commands for the inverter. A PI controller is used to generate voltage commands for the inverter based on reference currents. A method is developed to obtain actual torque based on the desired torque generated by a virtual controller, which can be any suitable robot motion control algorithm, for instance inverse dynamics. A novel optimization approach is used to generate reference currents that maximize the amount of regenerative energy stored in the ultracapacitor and motor inductance subject to the torque demanded by the virtual controller. An explicit solution is found for the optimal current references and it is shown that the well-known choice of a zero direct current component in the direct-quadrature frame is sub-optimal relative to our energy optimization objective. A simulation using a 2-link planar manipulator with one active and one semi-active joint is used to illustrate the results.
Estimating the Roll and Pitch Rate Signal Drift in a Moving Ground Vehicle
Authors: Zeng Xiangrui , Mohanty Amit
Published: November 2018

Ground vehicle roll rate and pitch rate signals coming from the inertial sensors usually suffer from the drift problem: the sensor readings are slightly biased with respect to the true values. This unknown drift will have a negative impact on many control applications using these roll and pitch rate signals. This paper presents a method to estimate this drift value while the vehicle is moving, without requiring very accurate vehicle velocity or yaw rate signals. First, a few global roll and pitch angle samples are approximately estimated at some special moments during the vehicle movement. Then a linearized kinematic model is used to formulate a regression problem to estimate the drifts, given the global roll and pitch angle samples. CarSim simulation results show that the proposed method works well in both small and large drift situations.
Stable Cadence Tracking of Admitting Functional Electrical Stimulation Cycle
Authors: Cousin Christian A. , Duenas Victor H. , Rouse Courtney A. , Dixon Warren E.
Published: November 2018

Rehabilitation robotics and functional electrical stimulation (FES) are two promising methods of rehabilitation for people with neurological disorders. In motorized FES cycling, both the rider and the motorized cycle must be controlled for cooperative human-machine interaction. While rehabilitation goals vary widely, FES cycling traditionally rejects rider disturbances to accomplish cadence and power tracking; however, this paper ensures that the cycle accommodates the rider without rejecting rider disturbances as a means to promote function and strength recovery while ensuring rider safety. A cadence and admittance controller are developed to activate the cycle’s electric motor and the rider’s leg muscles through FES when kinematically efficient. Using a single set of combined cycle-rider dynamics, a Lyapunov-like switched systems analysis is conducted to conclude global exponential cadence tracking. A subsequent passivity analysis is conducted to show the admittance controller is passive with respect to the rider. For a desired cadence of 50 RPM, preliminary experiments on one able-bodied participant and one participant with spina bifida demonstrate tracking errors of −0.07±2.59 RPM and −0.20±3.86 RPM, respectively.
Guarantee Performance ICC-LPV Control With Sensor Aging
Authors: Madhag Aqeel , Zhu Guoming George
Published: November 2018

A faulty sensor may lead to degraded system performance, unstable system, or even a fatal accident. On the other hand, the increasing need for safety and reliability has motivated the development of fault-tolerant control (FTC) techniques. This paper proposes a robust fault-tolerant gain-scheduled noisy output-feedback controller (GSNOF) that guarantees system stability and performance in the presence of sensor aging under control input constraints, where the sensor performance degradation due to aging is modeled by its measurement noisy covariance. The closed-loop system stability and performance, in terms of numerical complexity, computation time, and ℋ2 performance, are studied. The proposed controller is compared in simulations with the published results, which shows that the proposed controller is capable of guaranteeing the stability, performance with reduced numerical complexity and computation load under gradual sensor performance degradation, and it is feasible for real-time control.
Barrier Lyapunov Function Based Control of a Flexible Link Co-Robot With Safety Constraints
Authors: Song Siyang , She Yu , Wang Junmin , Su Haijun
Published: November 2018

In this paper, a control design for a flexible link co-robot with safety constraints is proposed. The safety constraints are converted to the constraints on the tip position and velocity. To handle this constrained control problem, a barrier Lyapunov function (BLF) is employed in the control design. The derivative of the logarithmic BLF is more complicated compared with the derivative of a quadratic Lyapunov function, which makes the problem of “explosion of terms” more serious. Thus, the dynamic surface control is used to deal with the problem. Furthermore, an extended state observer is adopted to estimate and compensate the uncertainty and disturbance in the system. The stability analysis via the singular perturbation theory shows the local practical exponential stability of the system. Simulation results indicate that the control performance is guaranteed without violation of the constraints.
Adaptive Haptic Shared Control Framework Using Markov Decision Processing
Authors: Ghasemi Amir H. , Rastgoftar Hossein
Published: November 2018

Semi-autonomous steering promises to combine the best of human perception, planning, and manual control with the precision of automatic control. This paper presents an adaptive haptic shared control scheme using Markov Decision Process (MDP) to keep human drivers in the loop yet free attention and avoid automation pitfalls. Using MDP, algorithms are developed to support the negotiation of authority between the human driver and automation system.
Dynamic Analyses of Directional Drilling Using Curved Beam Theorem
Authors: Feng Tianheng , Gu Qiuying , Kim Inho , Chen Dongmei
Published: November 2018

Directional drilling technique can provide flexibility in rig location selection as well as increase drilling and production efficiencies through extended reach to isolated reservoirs. However, as well complexity increases, analyzing the mechanical performance of the associated drillstring and its components becomes more difficult. A standard Finite element method (FEM) can accurately analyze directional drilling statics and dynamics by discretizing the structure into a series of straight beam elements. However, this method has a drawback of high computational cost. To increase the computational efficiency, this paper introduces the application of curved beam FEM to model directional drillstring. The minimum curvature method is applied to obtain directional well profiles in which the adjacent survey points are connected by circular arcs. Based upon this assumption, the curved beam is used to model the curved drillstring to minimize the discretization error and to increase the computational efficiency. Static and dynamic analyses are carried out to verify the proposed method. As compared to the straight beam approximation method, fewer elements are needed to obtain a given accuracy, leading to more efficient simulations. The utility of the proposed model is also demonstrated through analyzing realistic drilling scenarios.
Collaborative Control of Multiple Robots Using Genetic Fuzzy Systems Approach
Authors: Sathyan Anoop , Ma Ou
Published: November 2018

This paper introduces a decentralized approach of collaborative control between multiple robots. A dynamic problem is considered to illustrate the effectiveness of this approach. The objective of this problem is to control three robots that are connected to a ball through elastic strings to bring the ball to a pre-defined target position. Since there is no communication between the robots, each robot does not know how the other robots are going to react at any instant. The only information available to the robots are the current and target positions of the ball. Genetic Fuzzy Systems (GFSs) are used to develop controllers for individual robots to tackle this problem. The nonlinearity of fuzzy logic systems coupled with the search capability of Genetic Algorithm (GA) provides an invaluable tool to design controllers for such tasks. The system is first trained through a set of scenarios and then applied to an extensive test set to test the effectiveness of the approach.
Sliding Mode Control of Low Cost Pressure Sensor Calibration Device
Authors: Lee Chang-Hwan , Ahn Deukhwan , Kim Sunghoon , Gwak Kwan-Woong
Published: November 2018

Low-cost pressure sensors are used for various purposes, but it have unique properties such as hysteresis characteristics and creep characteristics. Therefore, it should be calibrated according to the purpose of use. For this purpose, a calibration device capable of applying a precise and repetitive load was generated. The core performance required for the calibration equipment is force control which can accurately apply the target load. However, since the material that contacts the end-effector of the equipment is a rigid body, it is difficult to control due to its high-speed response characteristics, so a robust and stable sliding mode force controller have to be applied. To design the sliding mode force controller of the calibration equipment, dynamic model of the system was derived, and system identification was performed. In order to improve the performance of the system identification, system model was modified by applying the nonlinear model to the system similar to the Hammerstein model. We applied a nonlinear model compensator to the system model and designed sliding mode force control. To verify the performance of the designed controller, force control was applied to static and dynamic loads. It is confirmed through the verification experiment that the proposed sliding mode force controller has sufficient control performance.
Virtual Motion Camouflage Based Visual Servo Control of a Leaf Picking Mechanism
Authors: Defterli Sinem Gozde , Xu Yunjun
Published: November 2018

For a lately constructed disease detection field robot, the segregation of unhealthy leaves from strawberry plants is a major task. In field operations, the picking mechanism is actuated via three previously derived inverse kinematic algorithms and their performances are compared. Due to the high risk of rapid and unexpected deviation from the target position under field circumstances, some compensation is considered necessary. For this purpose, an image-based visual servoing method via the camera-in-hand configuration is activated when the end-effector is nearby to the target leaf subsequent to performing the inverse kinematics algorithms.

In this study, a bio-inspired trajectory optimization method is proposed for visual servoing and the method is constructed based on a prey-predator relationship observed in nature (“motion camouflage”). In this biological phenomenon, the predator constructs its path in a certain subspace while catching the prey. The proposed algorithm is tested both in simulations and in hardware experiments.
Modeling and Control of a Novel Variable-Stiffness Regenerative Actuator
Authors: dos Santos Erivelton Gualter , Richter Hanz
Published: November 2018

This paper focuses on the design, modeling and basic control of a variable stiffness actuator to be used in combination with a regenerative electromechanical drive system. Due to the use of a flexible beam, the actuator has the ability to store and return elastic potential energy. Also, an ultracapacitor is used in the electromechanical drive, which allows electrical energy storage and return. Moreover, elastic and electrostatic energies can be exchanged, resulting in a highly efficient and lightweight design which will be beneficial for robotic prostheses, exoskeletons and other orthotic devices. The paper presents a model and calculation method for large beam deflections and the integrated electromechanical actuator model. A semiactive virtual control strategy is used to decouple the mechanical dynamics from the charge dynamics and achieve position control of the actuator. Simulation results are presented to illustrate the control system and the energy exchange features.
Realizing Trajectory-Based Combustion Control in a Hydraulic Free Piston Engine via a Fast-Response Digital Valve
Authors: Zhang Chen , Sun Zongxuan
Published: November 2018

Previously, the authors have proposed the concept of piston trajectory-based combustion control enabled by a free piston engine (FPE) and shown its advantages on both thermal efficiency and emissions performance. The main idea of this control method is to design and implement an optimal piston trajectory into FPE and optimizes the combustion performance accordingly. To realize the combustion control in practice, it is obvious that the design of the optimal trajectory should consider the dynamic behaviors of the FPE’s actuation systems as well as variable load dynamics and fuels’ chemical kinetics.

In this paper, a comprehensive model describing the operation of a hydraulic FPE fueled by diesel under HCCI combustion mode is developed. Such a high fidelity model includes four parts, i.e. the piston dynamics, the hydraulic dynamics, the thermodynamics and the fuel’s chemical kinetics. Extensive simulation results are produced, showing that by varying the switching strategy of a fast-response digital valve, the hydraulic FPE can operate at different working loads in a stable manner. Additionally, analysis has been conducted to quantify the thermal efficiency as well as the frictional loss and throttling loss of the FPE. At last, a feedback control is developed to generate optimal switching strategies for the digital valve aimed to achieve the HCCI combustion phasing control. The resulted switching strategy of the digital valve not only increases the thermal efficiency by 0.76%, but also reduces frictional loss by 9.8%, throttling loss by 6.5% as well as NOx emission by 85.6%, which clearly demonstrates the effectiveness of the trajectory-based combustion control.
Identification of Compensatory Arterial Dynamics in Swine Using a Non-Invasive Sensor for Local Vascular Resistance
Authors: Wang Lu , Ansari Sardar , Ward Kevin R. , Najarian Kayvan , Oldham Kenn R.
Published: November 2018

Autoregulatory dynamics of the cardiovascular system play an important role in maintaining oxygenated blood transportation throughout the human body. In this work, a feedback dynamics model of the cardiovascular system with respect to heartrate and peripheral vascular resistance effects on longer-term blood pressure changes in the systemic circulation is presented. The model is identified from data taken from a swine test subject, instrumented in part with a wearable, non-invasive sensor for estimating peripheral arterial radius. Comparative simulations for the open and close loop model highlight significantly changed hemodynamics after hemorrhage.
Hysteresis Compensation Using Extended High-Gain Observer and Dynamic Inversion
Authors: Chowdhury Dhrubajit , Al-Nadawi Yasir Khudhair , Tan Xiaobo
Published: November 2018

Hysteresis is a nonlinearity exhibited by a wide class of smart materials, such as piezoelectrics and shape memory alloys, and it presents challenges in the control of smart material-actuated systems (for example, piezo-based nanopositioning systems). Existing methods for hysteresis compensation typically require an explicit model of the hysteresis, which tends to be high-dimensional operators and entails significant complexity in model identification and inversion. In this paper a novel hysteresis compensation method based on extended-high-gain observers and dynamic inversion is presented, which does not assume any specific hysteresis model. An extended high-gain observer is used to estimate the hysteresis output as well as other unknown dynamics of the system model, and then dynamic inversion is implemented to cancel the effect of hysteresis. With a mild assumption on the system and the input nonlinearity, the analysis of the closed-loop system under output feedback shows fast performance recovery to the trajectories of a target system, and that the tracking error converges exponentially to zero. Simulation results are presented to support the efficacy of the proposed approach.
DMD-Based Distributed Flow Sensing for Bio-Inspired Autonomous Underwater Robots
Authors: Dang Fengying , Zhang Feitian
Published: November 2018

This paper presents a novel flow sensing method for autonomous underwater robots using distributed pressure measurements. The proposed flow sensing method harnesses a Bayesian filter and a dynamic mode decomposition (DMD)-based reduced-order flow model to estimate the dynamic flow environments. This data-driven estimation method does not rely on any analytical flow models and is applicable to many and various dynamic flow fields for arbitrarily shaped underwater robots. To demonstrate the effectiveness of the proposed distributed flow sensing approach, a simulation study with a Joukowski-foil-shaped underwater robot is presented.
Optimal Switching Time Control of UV Induced Cationic Curing Process
Authors: Beyene Shiferaw D. , Ayalew Beshah , Pilla Srikanth
Published: November 2018

This paper first describes a curing process model comprised of the coupled cure-kinetics and thermal evolution in a cationic polymerization of a single layer of material and then extends it to multi-mode curing of multiple layers. The model is characterized as a switching multi-mode dynamic system that switches when the UV source is turned off and when a new layer is added to the existing layer. These two switching conditions are explicitly defined. The model is then used to determine the optimal mode switching times and the final process time which are considered as manipulated control variables. This is done by explicitly deriving the necessary conditions of optimality for the multi-mode switching system. The results are first illustrated for a two-layer composite laminate and then the results of five-layer curing are briefly discussed to show the versatility of the proposed approach. The optimal switching times and final time result in minimal cure level deviation across the thick composite material.
An End-to-End Fully Automatic Bay Parking Approach for Autonomous Vehicles
Authors: Li Rui , Wang Weitian , Chen Yi , Srinivasan Srivatsan , Krovi Venkat N.
Published: November 2018

Fully automatic parking (FAP) is a key step towards the age of autonomous vehicle. Motivated by the contribution of human vision to human parking, in this paper, we propose a computer vision based FAP method for the autonomous vehicles. Based on the input images from a rear camera on the vehicle, a convolutional neural network (CNN) is trained to automatically output the steering and velocity commands for the vehicle controlling. The CNN is trained by Caffe deep learning framework. A 1/10th autonomous vehicle research platform (1/10-SAVRP), which configured with a vehicle controller unit, an automated driving processor, and a rear camera, is used for demonstrating the parking maneuver. The experimental results suggested that the proposed approach enabled the vehicle to gain the ability of parking independently without human input in different driving settings.
Using Compressive Sensing With In-Air Ultrasonic Measurements for Robotic Mapping
Authors: Sanchez Sean R. , Andersson Sean B.
Published: November 2018

Robotic mapping and simultaneous localization and mapping (SLAM) typically rely on sensors that produce a large number of measurements at many locations in an environment to produce an accurate map and, in the case of SLAM, the pose of the robot in that map. However, with the advent of small, low-power robots with insect-scale features, there is a need for techniques that can produce useful maps using limited capability sensors and a small number of measurements. In this work, we focus on the use of compressive sensing to extract local environment reconstructions from ultrasonic sensor measurements. We first examine a simplistic setting where a square pulse is emitted and use the returned echoes in a compressive sensing scheme to reconstruct the locations of objects inside the sensing cone. We then extend this to the more practical setting, accounting for the wave nature of the acoustic signal and corresponding issues of interference, showing that these can be accounted for in designing the measurement matrix of the compressive sensing description of the problem. We demonstrate the performance of our approach though several simulations.
Geometric Motion Planning for Systems With Toroidal and Cylindrical Shape Spaces
Authors: Gong Chaohui , Ren Zhongqiang , Whitman Julian , Grover Jaskaran , Chong Baxi , Choset Howie
Published: November 2018

Kinematic motion planning using geometric mechanics tends to prescribe a trajectory in a parameterization of a shape space and determine its displacement in a position space. Often this trajectory is called a gait. Previous works assumed that the shape space is Euclidean when often it is not, either because the robotic joints can spin around forever (i.e., has an 𝕊1 configuration space component, or its parameterization has an 𝕊1 dimension). Consider a shape space that is a torus; gaits that “wrap” around the full range of a shape variable and return to its starting configuration are valid gaits in the shape space yet appear as line segments in the parameterization. Since such a gait does not form a closed loop in the parameterization, existing geometric mechanics methods cannot properly consider them. By explicitly analyzing the topology of the underlying shape space, we derive geometric tools to consider systems with toroidal and cylindrical shape spaces.
Design of a Periodic Event-Based Repetitive Controller With Dynamic Output Feedback for Linear Systems
Authors: Ma Guoqi , Pagilla Prabhakar R.
Published: November 2018

In this paper a periodic event-based repetitive controller with dynamic output feedback is designed for linear systems with exogenous disturbances. The periodic event mechanism is designed such that within any two event triggering instants, the dynamic output feedback controller is open which substantially reduces the control and communication burden when the output does not change significantly. First, by employing the input delay approach, the overall system consisting of the physical plant, the repetitive controller, and the dynamic output feedback controller with periodic event-triggering mechanism is modeled as a closed-loop time-varying delay system. Then, sufficient conditions in terms of linear matrix inequalities are derived to ensure that the closed-loop system is asymptotically stable with a prescribed H∞ attenuation performance level. The controller gains are synthesized by using a matrix decomposition technique. A numerical example is provided to evaluate the proposed design approach.
Individualized Inter-Stimulus Interval Estimation for Neural Facilitation in Human Motor System: A Particle Filtering Approach
Authors: Takemura Kentaro , Kim Euisun , Ueda Jun
Published: November 2018

Quantitative understanding of the human neuromotor system is essential for the implementation of the future robotic therapeutic exercises. For this purpose, sensorimotor adaptations in voluntary and involuntary movements facilitated by peripheral stimulation and resultant motor-evoked potentials (MEP) must be well characterized. One such facilitation exercise is paired associative stimulation (PAS). However, effective inter-stimulus intervals between cortical and peripheral stimulations are highly variable between individuals due to different physiological characteristics. Past studies measured MEPs in a wide range of time by incrementally varying inter-stimulus intervals to find the optimal interval in a specific subject, which has been a time-consuming process. This paper develops a search algorithm based on particle filtering to estimate individualized inter-stimulus intervals for PAS with mechanical muscle tendon stimulation realized by a pneumatically-operated robotic neuromodulatory system. The particle filter-based method reduces the number of PAS trials 70%–80% in comparison to the conventional incremental method. An accelerometer attached to the robotic system that measures exact timings of tendon stimulation can further reduce the number of trials.
Modeling the Transport Dynamics in Gasoline Particulate Filters
Authors: Korneev Svyatoslav , Onori Simona
Published: November 2018

We develop the flow and the particulate transport models in a wall-flow gasoline particulate filter (GPF). The filter is constituted of inlet channels which are separated from outlet channels by a porous wall. We model the flow inside the channel using incompressible Navier-Stokes equation coupled with the spatially averaged Navier-Stoke equation for the porous wall. For the particulate transport, we use coupled advection and spatially averaged advection-reaction equations, where the reaction term models the particles trapping. The concentration of deposited particulates at the back of the filter downstream the flow increases with Reynolds number. These results are in agreement with the published experimental measurements of the spatial distribution of particles inside the filter.
Human-Robot Trust Integrated Task Allocation and Symbolic Motion Planning for Heterogeneous Multi-Robot Systems
Authors: Zheng Huanfei , Liao Zhanrui , Wang Yue
Published: November 2018

This paper presents a human-robot trust integrated task allocation and motion planning framework for multi-robot systems (MRS) in performing a set of parallel subtasks. Parallel subtask specifications are conjuncted with MRS to synthesize a task allocation automaton. Each transition of the task allocation automaton is associated with the total trust value of human in corresponding robots. A dynamic Bayesian network (DBN) based human-robot trust model is constructed considering individual robot performance, safety coefficient, human cognitive workload and overall evaluation of task allocation. Hence, a task allocation path with maximum encoded human-robot trust can be searched based on the current trust value of each robot in the task allocation automaton. Symbolic motion planning (SMP) is implemented for each robot after they obtain the sequence of actions. The task allocation path can be intermittently updated with this DBN based trust model. The overall strategy is demonstrated by a simulation with 5 robots and 3 parallel subtask automata.
A Robust and Optimal Visual Tracking Method With Blocking Obstacles and Water Reflection Noises
Authors: Yi Xiongfeng , Chen Zheng
Published: November 2018

Image-based tracking has been widely used to obtain the position and velocity information of a moving object in a 2-dimensional or 3-dimensional space. However, the tracking process is always affected by reflection noises and blocking obstacles in the environment. This paper provides a robust and optimal algorithm for tracking a moving object on the surface of water. First, we create a matrix to project the image pixels back to the real world coordinate. Second, color and shape tests are used to recognize the object and a vector is used to represent the object. If the object is partially blocked by the obstacles or the reflection from the water surface, the vector is used to predict the position of the body. In the real-time tracking, a Kalman filter is used to optimize the prediction. We tested our algorithm by tracking a submarine on the water surface of a tank. Experimental results show that the visual tracking method is robust to reflection noises and blocking obstacles.
Hierarchical Input-Output Decoupling Control for Vehicle Rollover Mitigation
Authors: Wang Fengchen , Chen Yan
Published: November 2018

In this paper, a hierarchical input-output decoupling controller is proposed to simultaneously prevent vehicle rollover and keep the input-output stability of vehicle planar motion. A four-degree-of-freedom nonlinear vehicle dynamics model with four-wheel steering (4WS) and four in-wheel motors (4IWMs) is first developed. Then, in the high-level control design, the roll dynamics is decoupled from the planar motion using the general longitudinal and lateral forces. The decoupled roll dynamics is proved to perform as a linear system with an exponentially stable equilibrium. Moreover, the general yaw moment is also determined in the high-level control through the input-output stability analysis for tracking a yaw rate reference. In the low-level control design, the active 4WS control and direct yaw moment control are applied through a control allocation method to satisfy and distribute the virtual control obtained from the high-level control. Demonstrated by co-simulations integrating with CarSim® and MATLAB/Simulink®, the proposed hierarchical input-output decoupling control can successfully prevent the impending rollover and stabilize the vehicle planar motion.
Lissajous-Like Scan Pattern for a Nodding Multi-Beam Lidar
Authors: Benson Michael , Nikolaidis Jonathan , Clayton Garrett M.
Published: November 2018

In this paper, trajectory design for a nodding multi-beam Lidar system is studied. While the multi-beam Lidar is inherently 3-dimensional and does not require nodding to create a 3D scan, the vertical resolution of these units can be limited, depending on the number of Lidar beams and their spread. This is especially important when viewing small objects and objects at distance. This vertical resolution can be improved by placing the Lidar on a nodding mechanism, allowing the beams to be repositioned. Typically, this mechansism undergoes a raster scan pattern, where the Lidar is slowly rotated and each line of Lidar data is collected in order. In contrast, this work presents the use of Lissajous-like scan pattern, in which the depth points are collected while the cradle is moving quickly. This trajectory allows for a trade-off between scan speed and resolution that is not possible when using a raster scan. In this paper, relevant theory and prior work is presented, simulations are shown that support the proposed theory, and proof-of-concept experiments are performed to show the feasibility of the approach.
Reconfigurable Fault-Tolerant Tilt-Rotor Quadcopter System
Authors: Kumar Rumit , Sridhar Siddharth , Cazaurang Franck , Cohen Kelly , Kumar Manish
Published: November 2018

In this paper, fault-tolerance characteristics of a reconfigurable tilt-rotor quadcopter upon a propeller failure are presented. Traditional quadcopters experience instability and asymmetry about yaw-axis upon a propeller failure but the design and control strategy presented here can handle a complete propeller failure during flight. Fault-tolerance is achieved by means of structural and flight controller reconfiguration. The concept involves conversion of a tilt-rotor UAV into a T-copter. The dynamics and control of the tilt-rotor quadcopter are presented for ideal flight condition and for the reconfigured system in case of propeller failure. Analytical solution for trim flight conditions yielding zero angular rates for the UAV is derived. It has been shown that the structurally reconfigured UAV is controllable and completes the flight mission without much compromise in flight performance. The controllability and observability analysis of the reconfigured system is shown by state space formulation. The flight controllers for both dynamic models are analyzed and the applicability of the proposed concept is presented by propeller failure simulation during the way-point navigation.