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Journal Article

A Framework for Collaborative Robot (CoBot) Integration in Advanced Manufacturing Systems

2016-04-05
2016-01-0337
Contemporary manufacturing systems are still evolving. The system elements, layouts, and integration methods are changing continuously, and ‘collaborative robots’ (CoBots) are now being considered as practical industrial solutions. CoBots, unlike traditional CoBots, are safe and flexible enough to work with humans. Although CoBots have the potential to become standard in production systems, there is no strong foundation for systems design and development. The focus of this research is to provide a foundation and four tier framework to facilitate the design, development and integration of CoBots. The framework consists of the system level, work-cell level, machine level, and worker level. Sixty-five percent of traditional robots are installed in the automobile industry and it takes 200 hours to program (and reprogram) them.
Technical Paper

A Hardness Study on Laser Cladded Surfaces for a Selected Bead Overlap Conditions

2017-03-28
2017-01-0285
Laser cladding is used to coat a surface of a metal to enhance the metallurgical properties at the surface level of a substrate. For surface cladding operations, overlapping bead geometry is required. Single bead analyses do not provide a complete representation of essential properties; hence, this research focuses on overlapping conditions. The research scope targets the coaxial laser cladding process specifically for P420 stainless steel clad powder using a fiber optic laser with a 4.3 mm spot size on a low/medium carbon structural steel plate (AISI 1018). Many process parameters influence the bead geometrical shape, and it is assumed that the complex temperature distributions within the process could cause subsequent large variations in hardness values. The bead overlap configurations experiments are performed with 40%, 50% and 60% bead overlaps for a three-pass bead formation.
Journal Article

A Methodology for Investigating and Modelling Laser Clad Bead Geometry and Process Parameter Relationships

2014-04-01
2014-01-0737
Laser cladding is a method of material deposition through which a powdered or wire feedstock material is melted and consolidated by use of a laser to coat part of a substrate. Determining the parameters to fabricate the desired clad bead geometry for various configurations is problematic as it involves a significant investment of raw materials and time resources, and is challenging to develop a predictive model. The goal of this research is to develop an experimental methodology that minimizes the amount of data to be collected, and to develop a predictive model that is accurate, adaptable, and expandable. To develop the predictive model of the clad bead geometry, an integrated five-step approach is presented. From the experimental data, an artificial neural network model is developed along with multiple regression equations.
Technical Paper

A Neural Network Approach for Predicting Collision Severity

2014-04-01
2014-01-0569
The development of a collision severity model can serve as an important tool in understanding the requirements for devising countermeasures to improve occupant safety and traffic safety. Collision type, weather conditions, and driver intoxication are some of the factors that may influence motor vehicle collisions. The objective of this study is to use artificial neural networks (ANNs) to identify the major determinants or contributors to fatal collisions based on various driver, vehicle, and environment characteristics obtained from collision data from Transport Canada. The developed model will have the capability to predict similar collision outcomes based on the variables analyzed in this study. A multilayer perceptron (MLP) neural network model with feed-forward back-propagation architecture is used to develop a generalized model for predicting collision severity. The model output, collision severity, is divided into three categories - fatal, injury, and property damage only.
Technical Paper

A Review of Human Physiological, Psychological & Human Biomechanical Factors on Perceived Thermal Comfort of Automotive Seats.

2017-03-28
2017-01-1388
Thermal comfort in automotive seating has been studied and discussed for a long time. The available research, because it is focused on the components, has not produced a model that provides insight into the human-seat system interaction. This work, which represents the beginning of an extensive research program, aims to establish the foundation for such a model. This paper will discuss the key physiological, psychological, and biomechanical factors related to perceptions of thermal comfort in automotive seats. The methodology to establish perceived thermal comfort requirements will also be presented and discussed.
Technical Paper

Active Suspension Handling Simulation using Cosimulation

2010-12-01
2010-01-1582
In this study the capabilities of a semi-active suspension and an active roll suspension are evaluated for comparison with a passive suspension. The vehicle used is a utility truck modeled as a multi-body system in ADAMS/Car while the ECU (electronic control unit) is built in Matlab/Simulink. Cosimulation is used in linking the vehicle model with the controller by exchanging the input and output values of each sub-system with one another. For the simulation models considered, results indicate that for a fish-hook cornering maneuver the semi-active suspension is limited in increasing vehicle performance while the active roll suspension significantly improves it. Further analysis is needed to confirm these findings.
Journal Article

An Enabling Study of Diesel Low Temperature Combustion via Adaptive Control

2009-04-20
2009-01-0730
Low temperature combustion (LTC), though effective to reduce soot and oxides of nitrogen (NOx) simultaneously from diesel engines, operates in narrowly close to unstable regions. Adaptive control strategies are developed to expand the stable operations and to improve the fuel efficiency that was commonly compromised by LTC. Engine cycle simulations were performed to better design the combustion control models. The research platform consists of an advanced common-rail diesel engine modified for the intensified single cylinder research and a set of embedded real-time (RT) controllers, field programmable gate array (FPGA) devices, and a synchronized personal computer (PC) control and measurement system.
Technical Paper

An Experimental Method to Study the Sensitivity of Transmission Laser Welding of Plastic Parts to Interfacial Gaps

2009-04-20
2009-01-1298
Hollow polymer-based automotive components cannot, in general, be directly injection molded because they cannot be ejected from the mold. The common practice is to injection mold two or more parts, and then join these together with a welding process. Of the many joining process available, laser welding has an advantage in geometric design freedom. The laser weld joints are also generally stronger than those of vibration welds because the weld joints are located in the walls rather than on external flanges. Eliminating the external flanges also makes the part more compact. In transmission laser welding processes, the laser beam passes through a transparent part to its interface with an opaque part. The beam energy is absorbed near the interface in the opaque part, and heat flows back across to the transparent half to make the weld pool. So successful laser welds are possible only when there is a continuous interfacial fit between the parts.
Technical Paper

An Investigation of Near-Spark-Plug Flow Field and Its Effect on Spark Behavior

2019-04-02
2019-01-0718
In the recent decades, the emission and fuel efficiency regulations put forth by the emission regulation agencies have become increasingly stringent and this trend is expected to continue in future. The advanced spark ignition (SI) engines can operate under lean conditions to improve efficiency and reduce emissions. Under such lean conditions, the ignition and complete combustion of the charge mixture is a challenge because of the reduced charge reactivity. Enhancement of the in-cylinder charge motion and turbulence to increase the flame velocity, and consequently reduce the combustion duration is one possible way to improve lean combustion. The role of air motion in better air-fuel mixing and increasing the flame velocity, by enhancing turbulence has been researched extensively. However, during the ignition process, the charge motion can influence the initial spark discharge, resulting flame kernel formation, and flame propagation.
Technical Paper

Control-Oriented Model for Electric Power Steering System

2006-04-03
2006-01-0938
Electric power steering (EPS) systems have been used to replace hydraulic power steering systems in vehicles. How to enhance the safety and reliability while reducing the manufacturing cost of EPS systems is still of strong interest to the automotive industry. In this paper, modeling analysis is conducted for advanced control of electric power steering system. Specifically, a mathematical model is proposed for a column-mounted EPS system and then a simplified model for control design purpose is proposed. Issues that need to be addressed, such as noise/ disturbance attenuation as well as potential fault detection/tolerance are analyzed. Simulation using CarSim™ is also presented for an optimal control design using the simplified model as an example to validate the proposed ideas.
Technical Paper

Cosimulation of Active Suspension

2005-04-11
2005-01-0984
The purpose of this study is to determine the feasibility of simulating an active suspension using cosimulation. The vehicle used is a utility truck created in ADAMS/View while the E.C.U. (electronic control unit) is implemented in Simulink for both a fully-active and semi-active controller. The LQR (Linear Quadratic Regulator) is used for the fully-active system while the semi-active system uses a switching law adopted from Karnopp et al. {1}. Nonlinear and linear vehicle models are compared and the influence of suspension bushings is examined. All simulations undertaken are geared towards evaluating the ride capabilities of such systems.
Technical Paper

Effect of Cooling Rates on the Microstructure Evolution and Eutectic Formation of As-cast Mg-Al-Ca Alloys

2009-04-20
2009-01-0789
A Mg-5.0wt.%Al-2.0wt.%Ca alloy (AC52) was cast at different cooling rates varying from 0.5 to 65 °C/s. The dendrites was characterized by determining the secondary dendrite arm spacing (SDAS) and the volume fraction of secondary eutectic phases with the linear intercept and point counting methods, respectively. The SDAS decreases significantly with increasing cooling rates, while the volume fraction of the eutectic phase increases from 10.8 ± 1.44 vol.% at 0.5 °C/s to 20.4 ± 1.52 vol.% at 20 °C/s. However, a further increase in cooling rate beyond 20 °C/s has limited influence on the volume fraction of eutectic phases. A large number of dispersed eutectic phases were observed in the primary α-Mg of the alloys cast at low cooling rates. Although, at the microscale, there were no dispersed eutectic phases in alloys cast at a high cooling rate of 30 °C/s, nanoscale eutectic phases were found by TEM observation.
Technical Paper

Energy Efficiency Analysis between In-cylinder and External Supplemental Fuel Strategies

2007-04-16
2007-01-1125
Preliminary empirical and modeling analyses are conducted to evaluate the energy efficiency of in-cylinder and external fuel injection strategies and their impact on the energy required to enable diesel particulate filter (DPF) regeneration for instance. During the tests, a thermal wave that is generated from the engine propagates along the exhaust pipe to the DPF substrate. The thermal response of the exhaust system is recorded with the thermocouple arrays embedded in the exhaust system. To implement the external fuel injection, an array of thermocouples and pressure sensors in the DPF provide the necessary feedback to the control system. The external fuel injection is dynamically adjusted based on the thermal response of the DPF substrate to improve the thermal management and to reduce the supplemental energy. This research intends to quantify the effectiveness of the supplemental energy utilization on aftertreatment enabling.
Technical Paper

Engine Fault Detection Using Vibration Signal Reconstruction in the Crank-Angle Domain

2011-05-17
2011-01-1660
Advanced engine test methods incorporate several different sensing and signal processing techniques for identifying and locating manufacturing or assembly defects of an engine. A successful engine test method therefore, requires advanced signal processing techniques. This paper introduces a novel signal processing technique to successfully detect a faulty internal combustion engine in a quantitative manner. Accelerometers are mounted on the cylinder head and lug surfaces while vibration signals are recorded during engine operation. Using the engine's cam angular position, the vibration signals are transformed from the time domain to the crank-angle domain. At the heart of the transformation lies interpolation. In this paper, linear, cubic spline and sinc interpolation methods are demonstrated for reconstructing vibration signals in the crank-angle domain.
Technical Paper

Evaluation of Low Mileage GPF Filtration and Regeneration as Influenced by Soot Morphology, Reactivity, and GPF Loading

2019-04-02
2019-01-0975
As European and Chinese tailpipe emission regulations for gasoline light-duty vehicles impose particulate number limits, automotive manufacturers have begun equipping some vehicles with a gasoline particulate filter (GPF). Increased understanding of how soot morphology, reactivity, and GPF loading affect GPF filtration and regeneration characteristics is necessary for advancing GPF performance. This study investigates the impacts of morphology, reactivity, and filter soot loading on GPF filtration and regeneration. Soot morphology and reactivity are varied through changes in fuel injection parameters, known to affect soot formation conditions. Changes in morphology and reactivity are confirmed through analysis using a transmission electron microscope (TEM) and a thermogravimetric analyzer (TGA) respectively.
Technical Paper

Heat Release Based Adaptive Control to Improve Low Temperature Diesel Engine Combustion

2007-04-16
2007-01-0771
Heat-release and cylinder pressure based adaptive fuel-injection control tests were performed on a modern common-rail diesel engine to improve the engine operation in the low-temperature combustion (LTC) region. A single shot injection strategy with heavy amount of exhaust gas recirculation (EGR) was used to modulate the in-cylinder charge conditions to achieve the low-temperature combustion. Adaptive fuel-injection techniques were used to anchor the cylinder pressure characteristics in the desired crank angle window and thereby stabilize the engine operation. The response of the adaptive control to boost, fueling, and engine speed variations was also tested. A combination of adaptive fuel-injection and automatic boost/back-pressure controls had helped to make the transient emissions comparable to the steady-state LTC emissions.
Technical Paper

High Energy Ignition Strategies for Diluted Mixtures via a Three-Pole Igniter

2016-10-17
2016-01-2175
A three-pole spark igniter, with the concept to broaden the ignition area, is employed in this paper to investigate the effect of spark discharge strategies on the early ignition burning process. The prototyped three-pole igniter has three independent spark gaps arranged in a triangular pattern with a circumradius of 2.3 mm. Direct-capacitor discharge techniques, utilizing close-coupled capacitors parallel to the spark gap, are applied on the three-pole igniter to enhance either the transient spark power or the overall energy. In particular, the simultaneous discharge of high energy plasma on three spark gaps can produce a surface-like ignition process which intensifies the plasma-flame interaction, thereby producing a rapid flame kernel development. The ignition strategies are evaluated in both constant volume combustion vessels and a modified single-cylinder metal engine.
Technical Paper

Identification of Damage Parameters Using Virtual Fields Method and Finite Element Model Updating

2007-04-16
2007-01-0999
Whole field displacement/strain measurement of automotive components can be done efficiently by digital image correlation based technique. Inverse problems with this kind of input data, such as the identification of damage parameters/effective modulus in different part of a component, can be pursued by either virtual fields method or finite element model updating. In this paper, the two methods are applied to the identification of a tension plate with a circular hole, and different aspects of the two methods are discussed. It is found that the success of virtual fields method relies on the choice of a set of optimal virtual displacement fields; finite element model updating, on the other hand, can be applied to any geometry and any load condition, and can also be applied to problems where only limited number of measurements are available. However, its performance relies on the choice of optimization algorithms.
Technical Paper

Improving Virtual Durability Simulation with Neural Network Modeling Techniques

2005-04-11
2005-01-0483
Neural networks are flexible modeling tools that can be used in conjunction with multi-body dynamics models to better predict nonlinear behaviour of components. This paper focuses on a process that incorporates a neural network model of a nonlinear damping force into a single degree of freedom mass-spring-damper model. Software tools and their interaction are specified. The verification of this process is the focal point of this paper and is a necessary step before further correlation studies can be performed on more complex component representations.
Technical Paper

In-Cylinder Pressure Measurements with Optical Fiber and Piezoelectric Pressure Transducers

2002-03-04
2002-01-0745
Highly accurate cylinder pressure data can be acquired using a wall-mounted and water-cooled quartz piezoelectric transducer. However, this type of transducer does not satisfy the cost and packaging constraints when used in a production engine application. A potential solution to these issues that has been the interest of many is the much smaller and less expensive optical fiber based pressure transducer. This research compares Kistler piezoelectric transducers to Optrand optical fiber transducers. The influence of the transducer type and mounting arrangement on the quality of cylinder pressure data was examined. The transducers were evaluated on a DaimlerChrysler 4.7L V-8 Compressed Natural Gas fuelled test engine. The analysis method is comprised of examining measured individual cycle and ensemble-averaged cylinder pressure records to assess the quality of the data and its usefulness for engine management.
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