Browse Topic: Stop / start technology

Items (90)
Find
LIN Network for Vehicle ApplicationsJ2602-1_202510 (Current)10/1/2025
This document covers the requirements for SAE implementations based on ISO 17987:2016. Requirements stated in this document will provide a minimum standard level of performance to which all compatible ECUs and media shall be designed. This will assure full serial data communication among all connected devices regardless of supplier.The goal of SAE J2602-1 is to improve the interoperability and interchangeability of LIN devices within a network by adding additional requirements that are not present in ISO 17987:2016 (e.g., fault tolerant operation, network topology, etc.).The intended audience includes, but is not limited to, ECU suppliers, LIN controller suppliers, LIN transceiver suppliers, component release engineers, and vehicle system engineers.The term “master” has been replaced by “commander” and term “slave” with “responder” in the following sections.
Vehicle Architecture For Data Communications Standards
Analytical Methods for Aircraft Seat Design and EvaluationARP5765B (Current)3/30/2021
This SAE Aerospace Recommended Practice (ARP) defines a means of assessing the credibility of computer models of aircraft seating systems used to simulate dynamic impact conditions set forth in Title 14, Code of Federal Regulations (14 CFR) Parts 23.562, 25.562, 27.562, and 29.562. The ARP is applicable to lumped mass and detailed finite element seat models. This includes specifications and performance criteria for aviation specific virtual anthropomorphic test devices (v-ATDs). This document provides a recommended methodology to evaluate the degree of correlation between a seat model and dynamic impact tests. This ARP also provides best practices for testing and modeling designed to support the implementation of analytical models of aircraft seat systems. Supporting information within this document includes procedures for the quantitative comparison of test and simulation results, as well as test summaries for data generated to support the development of v-ATDs and a sample v-ATD calibration report.
Aircraft SEAT Committee
Effects of Using an Electrically Heated Catalyst on the State of Charge of the Battery Pack for Series Hybrid Electric Vehicles at Cold Start2020-01-04444/14/2020
Battery models are being developed as a component of the powertrain systems of hybrid electric vehicles (HEVs) to predict the state of charge (SOC) accurately. Electrically heated catalysts (EHCs) can be employed in the powertrains of HEVs to reach the catalyst light off temperature in advance. However, EHCs draw power from the battery pack and hence sufficient energy needs to be stored to power auxiliary components. In series HEVs, the engine is primarily used to charge the battery pack. Therefore, it is important to develop a control strategy that triggers engine start/stop conditions and reduces the frequency of engine operation to minimize the equivalent fuel consumption. In this study, a battery pack model was constructed in MATLAB-Simulink to investigate the SOC variation of a high-power lithium ion battery during extreme engine cold start conditions (-7°C) with/without application of an EHC. The EHC was simulated in MATLAB to determine the energy required to heat the catalyst during cold start conditions. The effect of the EHC in emissions purification at -7°C was studied using a three-way catalyst (TWC) model. The EHC was operated only during the initial few seconds before the engine start to increase the bed temperature of the catalyst. This was found to have a significant impact on exhaust gas emissions even under cold start conditions. However, powering the EHC lowered the SOC of the battery pack, triggering the engine to run and consume more fuel. Hence, an engine ON/OFF control strategy was proposed to control the engine operation conditions and effectively charge the battery pack. The SOC variation of the battery pack and the effects on emissions and fuel consumption were simulated and compared with/without the EHC. The battery model was validated with a control strategy proposed in simulations at 23°C and a parameter study was conducted at -7°C.
Sivakumar, Suchitra, Shingyouchi, Hajime, Yan, Xieyang, Okajima, Toshinori, Yamaguchi, Kyohei, Kusaka, Jin, Nagata, Makoto
Stop & Start technology influence on Brazilian urban off-cycle - Simulated versus experimental data analysis2019-36-02861/13/2020
The applied technologies to increase vehicle energy efficiency oftentimes have not shown the same benefits in standard laboratory testing when compared to off-cycle. The off-cycle values represent a substantial amount of the overall regulated reduction in emissions for the regulatory programs and the exact extent of this benefice depends on how large the regulatory reduction is considered. In many countries, the energy efficiency legislation considers the off-cycle credits, since it has been demonstrated, and encourages the automakers to use new and innovative technologies, resulting in improvements in vehicle energy efficiency. On the other hand, off-cycle benefits are difficult to measure due to the changes in the environmental conditions, traffic, temperature and others. The vehicles operating in real life have more diverse conditions than on the standards test cycle. The Start & Stop technology fuel consumption reduction is a good example of this. The "Rota 2030" is the new Brazilian legislation approved at the end of 2018, considered this benefit to some technologies. In order to identify those benefits, this work will present and analyze the vehicle fuel consumption reduction provide by Start & Stop technology on a Brazilian urban off-cycle and the data is enable in future comparisons with other technologies in the same real drive cycle.
Figueiredo, Eduardo F., Campos, Carlos H. F., Pujatti, Fabrício J.P.
Characterization of GDI PM during Vehicle Start-Stop Operation2019-01-00501/15/2019
As the fuel economy regulations increase in stringency, many manufacturers are implementing start-stop operation to enhance vehicle fuel economy. During start-stop operation, the engine shuts off when the vehicle is stationary for more than a few seconds. When the brake is released by the driver, the engine restarts. Depending on traffic conditions, start-stop operation can result in fuel savings from a few percent to close to 10%. Gasoline direct injection (GDI) engines are also increasingly available on light-duty vehicles. While GDI engines offer fuel economy advantages over port fuel injected (PFI) engines, they also tend to have higher PM emissions, particularly during start-up transients. Thus, there is interest in evaluating the effect of start-stop operation on PM emissions. In this study, a 2.5L GDI vehicle was operated over the FTP75 drive cycle. Runs containing cold starts (FTP-75 cycle Phases 1 & 2) and multiple runs containing hot starts (FTP-75 cycle Phases 3 & 4) were performed each day. Note that the FTP-75 Phases 3 & 4 are identical to Phases 1 & 2 except that the engine is warmed up. Three fuels were evaluated: an 87 AKI gasoline (E0), a 21% splash blend of ethanol and the 87 AKI gasoline (E21), and a 12% splash blend of iso-butanol and the 87 AKI gasoline (iBu12). PM mass, transient particle number concentration and size distribution, and soot mass concentration were evaluated for both start-stop operation and no start-stop operation on each fuel. Three Phase 1 & 2 cycles and as many as 27 Phase 3 & 4 cycles were performed for each fuel-mode combination. Composite FTP mass emissions for E0 and iBu12 showed increased total PM emissions with start-stop operation, but E21 showed no difference. Statistical analysis of the effects of start-stop on PM number and soot emissions showed different trends for different fuels. For example, when E0 is used with start-stop operation, the particle number decreased but the soot mass tended to increase. The results of this study have implications for hybrid vehicle operation as well because the internal combustion engine in hybrid vehicles must stop and re-start during normal operation.
Storey, John M., Moses-DeBusk, Melanie, Huff, Shean, Thomas, John, Eibl, Mary, Li, Faustine
Custom Optomechanics in Industrial UV LasersTBMG-3328311/1/2018
Reliability and longevity directly impact the cost of using Q-switched, diode pumped, solid state, ultraviolet lasers in industrial applications. Damage to the intracavity harmonic crystal is often the major limiting factor in the lifetime of these lasers.
Information Sharing Protocol VCR (ISPVCR)TBMG-325168/1/2018
The Information Sharing Protocol (ISP) VCR (ISPVCR) is a software program written in Tcl/Tk that provides the capability to record and play back ISP data (telemetry, computations, ground system status, etc.) via Source Independent Telemetry Format (SITF) files. The ISPVCR provides a graphical user interface (GUI) that allows start/stop of the recording capability, specifying output file names, and start/stop of the playback of the SITF data file. The Orion Program chose to use the ISP to distribute data within the mission control center and other facilities. The ISPVCR package provides the capability to leverage legacy ISP software to provide record and playback of vehicle telemetry data via the ISP.
Modularized Simulation Tool to Evaluate Battery Solutions for 12 V Advanced Start Stop Vehicles2018-01-04464/3/2018
The 12 V advanced start stop systems can offer 5-8% fuel economy improvement over a conventional vehicle. Although the fuel economy is not as high as those of mild to full hybrids, its low implementation cost makes it an attractive electrification solutions for vehicles. As a result, the 12 V advanced start stop technology has been evolving fast in recent years. On one hand, battery suppliers are offering a variety of energy storage solutions such as stand-alone lead acid, stand-alone LFP/Graphite, dual batteries of lead acid parallel with NMC/LTO, LMO/LTO, NMC/Graphite, and capacitors, etc. For dual battery solutions, the architecture also varies from passive parallel connection to active switching. On the other hand, OEM are considering to leverage a lot more use out of traditional 12 V SLI (start, light, and ignition) for functions such as power steering, air conditioning, heater, etc. Depending on battery architecture and vehicle functioning design, the energy management strategy can easily become complicated. Since many variables are involved in the design of 12 V advanced start stop systems, an integrated simulation tool with a couple of modularized models including vehicle, batteries, and performance characterization have been developed. The modularized tool would help to evaluate many aspects of the design from motor size selection, power network management, battery evaluation, testing standardization. As a specific demonstration, in this work, we use the tool to compare three chemistries: stand-alone AGM, stand-alone LFP, and dual batteries of lead acid and LTO for different driving cycles including NEDC, WLTP, FTP72, and HWFET as function of motor size.
Zhang, Zhenli, Jin, Zhihong, Watson, Thomas
Evaluation of Thermal Environment in Vehicles for Occupant Comfort Using Equivalent Temperature of Thermal Manikin during Start-Stop Function with Energy Storage Evaporators2018-01-00594/3/2018
In recent years, start-stop systems have been implemented by many OEMs for improvement of fuel economy. When the engine stops, the occupant comfort typically deteriorates. Hence, the climate and fuel economy engineers are struggling to combine the passenger comfort and fuel economy. Especially in a vehicle cabin where the thermal environment becomes unsteady and highly non-uniform due to a start-stop. It is difficult to adapt any comfort evaluation index that have already been well established for a stationary/uniform space in building type environment in comparison to a vehicle cabin interior. The existing standard of ISO-14505-2 does not consider this for vehicle cabin interior condition. Hence, the authors have developed the occupant’s comfort prediction method under highly non-uniform condition and unsteady conditions and have established a new methodology [1].
Morishita, Masahiro, Uchida, Toshiya, Mathur, Gursaran D., Kato, Takenao, Matsunaga, Kazuhiko
An Engine Stop Start System with Driver Behavior Learning and Adaption for Improving the User Experience2018-01-06094/3/2018
Engine Stop/Start System (ESS) promises to reduce greenhouse emissions and improve fuel economy of vehicles. Previous work of the Authors was concentrated on bridging the gap of improvement in fuel economy promised by ESS under standard laboratory conditions and actual driving conditions. Findings from the practical studies lead to a conclusion that ESS is not so popular among the customers, due to the complexities of the system operation and poor integration of the system design with the driver behavior. In addition, due to various functional safety requirements, and traffic conditions, actual benefits of ESS are reduced. A modified control algorithm was proposed and proven for the local driving conditions in India. The ways in which a given driver behaves on the controls of the vehicles like Clutch and Brake Pedals, Gear Shift Lever were not uniform across the demography of study and varied significantly. In addition, Authors also discovered that some drivers also deployed the parking brake during an idle stop. Thus, a concept of autonomous learning algorithm was envisaged, which would learn the driver behavior on the controls which influence the functions of ESS and then adapt the same conditions to trigger the auto engine stop and restart. This was aimed at improving the user experience and yet ensure the benefits of the ESS. In this paper, the findings from previous works are analyzed to make grounds for the new submission and to identify the need for User Experience of ESS. The solution implemented to detect the driver behavior from the set of possible ways is discussed in detail and simulation case studies are discussed to ascertain the functions and benefits of the new algorithm.
Athani, Gopal, Gavarraju, Srinivasa Raju, Jain, Punit, Addala, Shashank, P, Satishkumar
Impact of the Future Fuel Economy Targets on Powertrain, Driveline and Vehicle NVH Development2017-01-17776/5/2017
The automotive industry continues to develop new technologies aimed at reducing overall vehicle level fuel consumption. Powertrain and driveline related technologies will play a key role in helping OEM’s meet fleet CO2 reduction targets for 2025 and beyond. Specifically, use of technologies such as downsized engines, idle start-stop systems, aggressive torque converter lock-up schedules, wide-ratio spread transmissions, and electrified propulsion systems are vital towards meeting aggressive fuel economy targets. Judicious combinations of such powertrain and driveline technology packages in conjunction with measures such as the use of low rolling resistance tires and vehicle lightweighting will be required to meet future OEM fleet CO2 targets. Many of the technologies needed for meeting the fuel economy and CO2 targets come with unique NVH challenges. In order to ensure customer acceptance of new vehicles, it is imperative that these NVH challenges be understood and solved. This paper will begin with an introduction of the legislative framework with respect to fuel economy and CO2 targets for light duty vehicles. Key megatrends of engine, transmission, driveline, and electrified propulsion systems will be examined, following which the NVH behavior of each sub-system will be illustrated. A combination of experimentally measured data and simulations will be used to demonstrate key NVH challenges such as high levels of combustion noise, increased driveline torsional excitation, start-stop refinement, shift quality, and high-frequency whine noise from motors/generators in electrified propulsion systems. Examples of component-level and system-level NVH countermeasures will be discussed. Finally, the use of advanced test and simulation-based methodologies for smooth NVH refinement of future propulsion systems will be illustrated using case study examples.
Wellmann, Thomas, Govindswamy, Kiran, Tomazic, Dean
VW finally fills its SUV gap with 2018 Atlas17AUTP06_116/1/2017
With the market rushing headlong toward trucks, SUVs and crossovers, Volkswagen has badly needed a mid-range SUV between its $25,000 compact Tiguan and $50,000-plus premium Touareg. And now, finally, it has one. Designed and engineered in Wolfsburg, built at VW's billion-dollar Chattanooga plant and riding on the modular MQB platform, the 2018 Atlas ($31,000 base price) enters production three years after the CrossBlue concept made the autoshow rounds. Atlas was developed as “a vehicle to go straight at the heart of the mid-size SUV market,” explained Michael Lovati, Vice President of VW's mid-size/full-size product line.
Witzenburg, Gary
Condition (Usage) Based Maintenance and SLL Computation using Flight Regime Recognition AlgorithmF-0073-2017-120825/9/2017
ABSTRACT Condition (Usage) Based Maintenance (CBM) function is becoming a standard and classical investigation topic for Original Equipment Manufacturers (OEM) for many reasons. Significant benefits can be earned by developing and using such functions: Better knowledge of the customer's usage of the helicopters, improvements in the building of the Design Usage Spectrums (DUS) for both high cycle fatigue mode (time ratio spent and occurrences of flight regimes) and low cycle fatigue mode (start/stop cycles, landing/take-off cycles, torque cycles, -), better understanding of the customer's own fleet's management, and of course maintenance optimization. In order to achieve this target and in particular the maintenance burden reduction, AH has developed a complete end-to-end CBM function proven to be efficient for customers. This paper intends to describe briefly the general concept already published, recall the expected benefits previously evaluated on H225, and focus deeper on the validation of the Flight Regime Recognition (FRR) Algorithm, allowing to confirm and reinforce the robustness of the function proposed. It details the means proposed by AH to validate the regime recognition and the potential credit, as well as the cautions to be taken when implementing such a function. General continued airworthiness and certification issues are also included in this paper, as required and proposed by AMC 29.1465 and AC29-2C MG15.
Laillet, Emmanuel, Maisonneuve, Pierre-Loic, Reveillon, Damien
A Model-Based Design Thinking Strategy for in-Vehicle Infotainment Features Development *CSP Meta QA Testing*2017-01-00073/28/2017
The advancement in connectivity technology is driving a shift in business models in almost every field. Automakers need to adapt to a new business model in which the platform (automobile) and the mobility solutions (Devices and Services) are enabled by a strong dynamic connectivity. To succeed in this business model, it is imperative to deliver an unparalleled customer experience. Traditional customer experiences focused only in the platform (automobile) are no longer sufficient to address the mobility needs. The development of in-vehicle features should consider both the platform and the connectivity in a single development scope. This paradigm shift sets new challenges for the in-vehicle features designers. Designers have to speak not only the language of the experience but rather a language to address different levels of abstractions to ensure effective communication with all stakeholders and developers including those outside the organization. In this paper a new strategy for the development of in-vehicle features is exposed. This strategy is based on embedding the Design Thinking framework within the traditional systems engineering process. This new concept proposes the customer experience at the center of the development process connected through models at different abstraction levels within the different design development layers and domains. This scheme, introduces early in-model verification gateways in each layer of the feature development process. As a proof of concept, this paper presents the development of an infotainment feature under the proposed strategy. Finally we highlight the impacts of this new approach on the design development cycle among others.
Saavedra, Jose-Guillermo, Makki, Asaad, Cruz, Raciel
Development of Predictive Powertrain State Switching Control for Eco-Saving ACC2017-01-00243/28/2017
In recent years, improvement of in-use fuel economy is required with tightening of exhaust emission regulation. We assume that one of the most effective solutions is ACC (Adaptive Cruise Control), which can control a powertrain accurately more than a driver. We have been developing a fuel saving ADAS (Advanced Driver Assistance System) application named “Sailing-ACC”. Sailing-ACC system uses sailing stop technology which stops engine fuel injection, and disengages a clutch coupling a transmission when a vehicle does not need acceleration torque. This system has a potential to greatly improve fuel efficiency. In this paper, we present a predictive powertrain state switching algorithm using external information (route information, preceding vehicle information). This algorithm calculates appropriate switching timing between a sailing stop mode and an acceleration mode to generate a “pulse-and-glide” pattern. In addition, future behavior of a preceding vehicle is predicted with a probabilistic algorithm to optimize switching timing. This algorithm uses a stereo camera and digital map information. As a result of driving experiments in a test course, fuel efficiency was improved by 43.4% in case of following travel around 40km/h. Additionally we evaluated practical performance of Sailing-ACC by simulation which simulated actual environment including a preceding vehicle and planimetric features. A result of following simulation was shown that the developed algorithm improved fuel efficiency by 38.8% during driving in a city area.
Imanishi, Yuto, Tashiro, Naoyuki, Iihoshi, Yoichi, Okada, Takashi
Integrated Systems Engineering Approach for Incremental 48Volt Hybrid Technology Introduction2017-01-16033/28/2017
Automotive product engineering is highly complex. Understanding the implications and opportunities of introducing new technology needs to be identified as early as possible in the vehicle design process. These earlier design considerations have the potential to deliver right-first-time designs and maximize integration opportunities, resulting in efficient, effective, competitive and holistic design solutions. Integrating new technology into existing vehicle architectures can preclude and restrain the opportunity for engineers to invent, discover and deliver new design solutions. To avoid this potential loss of opportunity, it is necessary to trace back to vehicle-level assumptions and attributes to confirm the technology delivers the desired output. The vehicle and system analysis enables engineers to consider all vehicle attributes and how their sub-system can enhance other vehicle systems. This paper describes a case study using Function Analysis, within a systems engineering framework applied to the design and integration of a 48V mild hybrid system (mHEV) for a diesel powertrain. The key deliverables were to improve fuel economy (CO2 reduction) through improved usage of stop/start technologies and the recuperation of kinetic energy during vehicle deceleration events. This case study also illustrates vertical integration of mHEV system functions to vehicle attributes. Further it supports a practical approach to the specific development of new innovative ideas using lateral thinking. It also shows the reliance on systems engineering within a multidisciplinary system concept design environment. This process will expedite model based systems engineering.
Naidu, Ashish, Brittle, Peter, Ma, Xiaoyu, Rutter, Brian
Arttest – a New Test Environment for Model-Based Software Development *CSP Meta QA Testing*2017-01-00043/28/2017
Modern vehicles become increasingly software intensive. Software development therefore is critical to the success of the manufacturer to develop state of the art technology. Standards like ISO 26262 recommend requirement-based verification and test cases that are derived from requirements analysis. Agile development uses continuous integration tests which rely on test automation and evaluation. All these drove the development of a new model-based software verification environment. Various aspects had to be taken into account: the test case specification needs to be easily comprehensible and flexible in order to allow testing of different functional variants. The test environment should support different use cases like open-loop or closed-loop testing and has to provide corresponding evaluation methods for continuously changing as well as for discrete signals. In a joint project of RWTH Aachen University and Ford, a new tool, Arttest, has been developed for testing model-based software. The tool uses a domain specific language to specify the tests. It offers different test evaluation methods for automated open- and closed-loop testing and reactive testing. It automatically executes the tests, evaluates the outputs and generates summary reports indicating passed tests and errors found. The paper presents the tool and its various unique propositions such as domain specific test language, the evaluation properties and other features like open-loop and closed-loop capabilities.
Wiechowski, Norbert, Rambow, Thomas, Busch, Rainer, Kugler, Alexander, Hansen, Norman, Kowalewski, Stefan
Manage and Optimize Power System to Maximize Steering Assist and Stop-Start Availability2017-01-11763/28/2017
Auto stop-start (Engine stop-start, ESS) has become a widely used feature to reduce fuel consumption and CO2 emissions particularly in congested cities. Typically, vehicles equipped with such systems include two DC power sources that are coupled in parallel: a primary and a secondary power source. The primary power source supplies energy to the starter to crank the engine, while the secondary power source supplies energy to the rest of the vehicle electric loads. During an auto-stop event, a controllable switch decouples the two power sources. Moreover, operating current, voltage and the State of Charge (SOC) are monitored to ensure enough energy for the next auto-start event. When any of these operating parameters are below the threshold values, the controllable switch opens to isolate the two batteries and then the engine is automatically started. This paper introduces a strategy to control the power usage of the Electric Power Assist Steering (EPAS) system for enhanced stop-start availability, optimal steering/EPAS assist, maximum fuel economy savings and minimum CO2 emissions. The algorithm predicts the energy demand by the customer and determines the next engine state based on the above mentioned criteria. The power system architecture uses a Lead Acid battery (Lead Acid, AGM and/or Enhanced) in parallel to a Lithium-ion (Li-ion) battery. Such architecture combines the advantages of the two technologies and supplies the required vehicle power over a wider operating range of ambient conditions. Moreover, the Li-Ion has voltage characteristics that are similar to the lead acid battery, and hence there is no need for any adjustments between the two power supplies. Measured data and results assure the ability of the introduced strategy to optimize between engine auto-stop/start and the EPAS assist.
Khafagy, Hafiz S.
Timing Analysis for Hypervisor-based I/O Virtualization in Safety-Related Automotive Systems2017-01-16213/28/2017
The increasing complexity of automotive functions which are necessary for improved driving assistance systems and automated driving require a change of common vehicle architectures. This includes new concepts for E/E architectures such as a domain-oriented vehicle network based on powerful Domain Control Units (DCUs). These highly integrated controllers consolidate several applications on different safety levels on the same ECU. Hence, the functions depend on a strictly separated and isolated implementation to guarantee a correct behavior. This requires middleware layers which guarantee task isolation and Quality of Service (QoS) communication have to provide several new features, depending on the domain the corresponding control unit is used for. In a first step we identify requirements for a middleware in automotive DCUs. Our goal is to reuse legacy AUTOSAR based code in a multicore domain controller. In an example use case scenario, we analyze the end-to-end latency for transmitting and receiving CAN messages in a system using a hypervisor-based virtualization approach. A model-based timing analysis and an implementation on a state-of-the-art automotive microcontroller shall help to assess the usability for safety-related domains. Additionally, the timing behavior is compared to a common AUTOSAR implementation. We could show that a well-configured hypervisor and scheduling can provide similar results as an AUTOSAR implementation under certain circumstances. Furthermore, a model-based timing analysis allows evaluating different hypervisor configurations without physical hardware.
Kohn, Andre, Schmidt, Karsten, Decker, Jochen, Sebastian, Maurice, Züpke, Alexander, Herkersdorf, Andreas
Aerospace Fluid Power Electrohydrostatic Module, Design, Performance and Test RecommendationsARP6154 (Current)3/15/2017
This Aerospace Recommended Practice provides general requirements for Electrohydrostatic Module (EHM) that is used in Electrohydrostatic Actuator (EHA) for aerospace applications. This document includes design, performance and test (production and qualification) requirements.
A-6B2 Electrohydrostatic Actuation Committee
Training and Qualification Program for Deicing/Anti-icing of Aircraft on the GroundAS6286 (Historical)11/29/2016
This document establishes the minimum training and qualification requirements for ground based aircraft deicing/anti-icing methods and procedures. All guidelines referred to herein are applicable only in conjunction with the applicable documents. Due to aerodynamic and other concerns, the application of deicing/anti-icing fluids shall be carried out in compliance with engine and aircraft manufacturers’ recommendations. The scope of training should be adjusted according to local demands. There are a wide variety of winter seasons and differences of the involvement between deicing operators and the level and length of training should therefore be adjusted accordingly. However, the minimum level of training shall be covered in all cases. As a rule of thumb, each hour of classroom training should at least equal the same amount (or include more) of practical training wherever this is relevant. Both basic and recurrent practical training shall be performed and documented periodically.
G-12T Training and Quality Programs Committee
Start/Stop Retrofit for Off-Highway Vehicles2016-36-026610/25/2016
The start/stop functionality is widely used as a fuel saving solution for on-highway vehicles, being constantly studied and implemented in new series models. The subject of this work is to demonstrate the same start/stop functionality applied as a retrofit solution for off road vehicles that have high fuel consumption and operate many hours a day. The start/stop retrofit (SSR) solution includes an ECU added in the vehicle acting as the system’s controller, which must be adapted according to its specific application. These interventions are important discussions topics and include electrical modifications, battery monitoring strategies, adapted ways to retrieve the vehicle data and an important safety study to secure all the modifications. The implementation of the start/stop system in a mining truck aims for a reduction on fuel consumption and CO2 emissions.
Ventura, Lucas, Junge, Thomas F., da Silva, Filipe A. P., de Oliveira, Rodrigo R., Malicheski, Thiago A.
Model-Based Evaluation of Chemistry Selection for Dual Energy Storages for 12V Advanced Start-Stop Vehicles2016-01-12094/5/2016
Passively parallelizing two energy storage systems, one is energy type and the other is power type, requires minimal modifications of auto makers and thus a cost-effective method to enable advanced start stop technology. Traditional lead acid battery, lithium-ion battery, capacitor, are all candidate chemistries for dual energy storage solutions. However due to the dual nature of the technology the open circuit potential, resistance, and some other control variables should match in order to achieve optimal performance. In this work we use coupled equivalent circuit model and electrochemical model to study a few options of dual systems, namely the lead acid with NMC/LTO, lead acid with LFP-Graphite, and lead acid with capacitor. A few charging and discharging pulses are designed and simulated to evaluate the regen receiving capability and cranking capability of different chemistries. Also a driving cycle is simulated for different battery combinations to characterize their fuel economy, heat generation, SOC range.
Zhang, Zhenli, Jin, Zhihong, Wyatt, Perry
A Novel Approach to Enhance Stop/Start Battery Life in a Vehicle with Micro Hybrid System Functions2016-01-00074/5/2016
Micro Hybrid Systems are essentially first step towards the electrification of the powertrains. They are aimed at improving the fuel efficiency of the conventional gasoline and diesel power trains with conventional 12 V electrical system, and thus reduce the CO2 emissions as well. Various technologies like Engine Stop-Start, Intelligent Alternator Control, and Electrical Energy Management Systems are included in the bracket of micro hybrid systems. These system functions demand a totally different approach for managing the SLI battery, which is a total departure from the conventional approach. Particularly, the Alternator Shutdown function of Intelligent Alternator Control maintains a calibrated average level of State of Charge, which is typically around 80%, to ensure that the battery can accept more current, during the energy recuperation, which indirectly improves fuel economy. However, continuous operation under partially discharged condition, results in the sulfation in the battery which is the main reason for the ageing of the battery. Symptoms of ageing include permanent loss of capacity, increase in internal resistance, etc. This paper discusses a novel approach of ensuring the life of the battery in the altered operating conditions of a Micro Hybrid System. A Charge Refresh Cycle is implemented in the Battery Management System, which periodically performs a refresh charge on the battery to ensure that the battery is not affected due to partially discharged conditions, without having to disconnect the battery from the vehicle, and without the need of a visit to a service station. This is achieved by implementing a timer and an engine start counter, based on which the control signals for the refresh charge are triggered. The system not only ensures the performance of the battery, but also ensures the return of designed life of the battery. The function was validated under controlled conditions on several samples of batteries, and it was observed that the battery life is restored back to the designed life.
Athani, Gopal, Dongare, Kapil, Balusu, Rajesh, Gupta, Subhabrata, Gavarraju, Srinivasa Raju
Design and Optimisation of the Propulsion Control Strategy for a Pneumatic Hybrid City Bus2016-01-11754/5/2016
A control strategy has been designed for a city bus equipped with a pneumatic hybrid propulsion system. The control system design is based on the precise management of energy flows during both energy storage and regeneration. Energy recovered from the braking process is stored in the form of compressed air that is redeployed for engine start and to supplement the engine air supply during vehicle acceleration. Operation modes are changed dynamically and the energy distribution is controlled to realize three principal functions: Stop-Start, Boost and Regenerative Braking. A forward facing simulation model facilitates an analysis of the vehicle dynamic performance, engine transient response, fuel economy and energy usage. To identify respectively (1) the maximum overall fuel economy, (2) the maximum amount of air and energy recovered during the braking and (3) the minimum loss of available energy during acceleration, a number of variables in the control strategy are selected in an optimisation process. Three optimisation algorithms are compared in different aspects of the control strategy: (1) using the Pattern Search to optimise the initial air tank pressure for every stop-start event in order to maximize the pressure increment in the air tanks; (2) conducting the Genetic Algorithm optimisation to find out the best gear change strategy during braking in order to maximize the energy recovery to the air tanks; and (3) implementing the multiobjective optimisation to simultaneously minimize the fuel consumption and the loss of available energy in the air flow during acceleration. The rationale for the choice of optimisation methods is explained and recommendations made for the development of energy management strategies in which a variety of different vehicle functions contribute to an overall fuel economy benefit.
Bao, Ran, Stobart, Richard
Powertrain Metric to Assess Engine Stop Start Refinement2015-01-21866/15/2015
Every automaker is looking for ways to improve the fuel economy of its vehicle fleet to meet the EPA greenhouse gas regulation, which translates into 2025 Corporate Averaged Fuel Economy of 54.5 mpg. Engine Stop Start technology will improve the fuel economy of the vehicle by shutting down the engine when the vehicle is stationary. While this is an established technology in Europe, it is beginning to gain momentum in North America, where NVH refinement is a stronger consideration. To utilize the fuel economy benefits of Stop Start technology in the North American market, the technology must be seamlessly incorporated into the vehicle. This paper gives an overview of characterizing an auto start based on the features of a few Powertrain-system-level metrics. Following the fundamentals of NVH, (Source, Path and Receiver) the receiver touch points will be less perceptible to vibration, if the powertrain-system source is made smoother. Tangential components, which are functions of cylinder pressure and crank angle, are the dominant forces during auto start. Six powertrain-system-level metrics that will define an auto start are developed: engine ramp rate; engine jerk during initial combustion; engine flaring; vibration dose value from the active side of the engine mounts; starter engagement time based on battery voltage; and near field sound level measured 15 cm away from starter. This paper recommends that all of these metric values be reduced to obtain better customer subjective and objective ratings. This paper also correlates these powertrain-system metrics with driver tactile and audible sensory response points.
Srinivasan, Sudharsan, Orzechowski, Jeff, Schoenherr, Michael
New Control Possibilities for Wireless SwitchesTBMG-221315/1/2015
Wireless controls have been widely accepted and embraced in the industrial community. Widespread use of monitoring devices in the process industry, the deployment of RFID components in a variety of industry segments, and the demonstrated performance of a large, installed base of the technologies serve as evidence of their viability.
Potentials of a 48 Volt Belt-Starter-Generator in the Powertrain of an Ultra-Light Vehicle2015-01-11554/14/2015
This paper focuses on the potentials of a Belt-Starter-Generator (BSG) in the context of an ultra-light vehicle prototype with a target curb weight of only 600 kg. Therefore, two hybrid approaches with a voltage level below 60 V are described and their potentials regarding electrical driving and CO2 reduction are analysed in detail. Introducing the ‘Cars Ultra-Light Technology’ (CULT) project, the holistic lightweight approach is described as a main requirement for the further hybrid investigations. In addition, a P2-hybrid structure with a 12 V BSG on the transmission input shaft enabled unique features despite the low voltage level and limited electrical power resources. The CO2 reduction for this powertrain combination is described and compared to a conventional stop start configuration. The validation process on a dynamic test rig is presented as well. As a next evolution step, the potentials when integrating a 48 V BSG in such a low weight vehicle are analysed and compared to those of a vehicle with a higher curb weight. Due to the extended hybrid functions, an efficiency based operating strategy is presented managing the use of the internal combustion engine (ICE) and the BSG in an intelligent way. Furthermore, the CO2 reduction in the NEDC and WLTP is calculated and the advantages of a 48 V Plug-In concept are presented.
Steffan, Robert, Hofmann, Peter, Geringer, Bernhard
Normally-Engaged Dual-Piston Clutch for Engine Stop-Start Application2015-01-11414/14/2015
For the conventional 6 speed automatic transmission with engine stop-start powertrain, an electrically-driven auxiliary pump is implemented to maintain the transmission line pressure as required to lock-up the CB1234 clutch during engine auto-stop conditions. Upon releasing the brake pedal, the transmission engages into first gear with the objective to accelerate the vehicle in a responsive manner. In this study, a novel normally-engaged dual-piston clutch concept is designed to keep the CB1234 clutch locked-up during engine auto-stop conditions with the intention to eliminate the auxiliary pump without compromising vehicle performance. This dual piston clutch concept requires a relatively low line pressure to release the normally-engaged clutch when needed, thus, minimizing the hydraulic pumping work. To explore the functionality of this concept under a wide-open-throttle (WOT) auto-start transition, modeling and simulation of the normally-engaged dual-piston clutch is completed. A component-level model of the dual-piston clutch and preloaded Belleville spring is developed in the AMESim environment. The model is refined and validated by comparing the simulated results with spin rig performance data. Important dynamic features, including the CB1234 clutch pressure and release pressure profiles are predicted and explained. The developed component model is integrated into a vehicle model and validated by comparing simulation and vehicle test data under auto-start conditions. Using the validated model, a parametric study is conducted to examine the effect of the hydraulic orifice size in the release piston fluid passage. The study identified the appropriate orifice size requirements, illustrating that the normally engaged dual-piston clutch has potential to lock-up the CB1234 clutch under wide-open-throttle auto-start condition.
Duan, Chengwu, Samie, Farzad, Hebbale, Kumaraswamy, Li, Dongxu, Lee, Chunhao
Experimental Investigation of Factors Affecting Odors Generating from Mobile AC Systems Equipped with Idling-Time Reduction Systems2015-01-03594/14/2015
In last 10 years or so, a number of OEMs are designing vehicles with start-stop function to save energy and to reduce pollution. For these systems, the situations in which air-conditioning systems are used have been changing with a significant increase in adoption of idle-time reduction systems (no idling-system). Blower fan remains operating at idle condition while compressor stops in most cases for these systems. In this case, the air temperature at the vent outlets increases. The increase in the air temperature under range of thermal boundary conditions around the evaporator causes a concern of odor to occur. This paper describes and explains experimental studies on changes in heat and humidity at the air outlets according to the switching operation of compressor and root cause analyses of odor coming from air-conditioning system for vehicles with start-stop function.
Uematsu, Satoki, Uehara, Toshiyuki, Uchida, Toshiya, Mathur, Gursaran D.
Improved Mobility with a Neutral, Motion-Amplifying Controller for an Experimental Exoskeleton2015-01-14004/14/2015
The number of seniors is rising worldwide. Exoskeleton devices can help seniors regain their lost power, balance, and agility, thus improving their quality of life. Exoskeleton devices and control strategies assist human gait. A common strategy is to use oscillator-based controllers, which “lock in” with the gait and help the subject walk faster using a phase lead characteristic. Such strategies are limited to gait assist only and are less effective in more general movements. These controllers can be detrimental in critical cases such as when the leg needs to execute a fast reactive stepping to stop a fall. We present a control strategy for a hip exoskeleton, which assists human leg motion by providing motion amplification at the hip joint. The controller is “neutral” because it assists any leg motion, not only a gait, and can help avoid falls by assisting reactive stepping. Our control strategy modifies the joint dynamics of the coupled human-exoskeleton system such that the desired dynamic response is achieved while guaranteeing stability. We define assistance as reducing the impedance and increasing the admittance of the coupled system. The dynamic response of the leg is defined by the frequency response profile of the magnitude of integral admittance (torque-to-angle relationship) of the coupled human-exoskeleton system, and assistance occurs when this profile is higher than that of the unassisted leg for all frequencies of interest. Our controller produces hip joint motion amplification and results in larger and faster leg swing motions, and can help recover the seniors' power and agility.
Nagarajan, Umashankar, Goswami, Ambarish
Design Considerations for Gearmotors in Long-Life ApplicationsTBMG-204209/1/2014
At first glance, the photo at the top is not appealing to any market — a pallet full of old gearmotors is not something one wants to think about after purchasing the necessary gearmotor/motor for their application. But think of it this way instead: these gearmotors were removed from their installation for a refurbishment project after being in service for 30 years. Sandia National Laboratories placed these gearmotors into service in their Heliostat Field in New Mexico in the 1970s. The gearmotors were used to position solar reflectors to concentrate light from all of the individual panels towards one point at the top of a tower. After 30 years, Sandia decided to upgrade the field with a new control system, and they decided to replace the still-operating gearmotors at the same time.
NVH Study of Stop & Start System and Optimized Solutions for Hybrid Vehicles2014-01-20686/30/2014
Many car manufacturers are introducing Stop & Start systems based on conventional ring gear starter, which represents an economical solution without heavy modifications of their existent architectures especially if they consider hybrid technology. However, this solution is unfortunately not very satisfying from NVH point of view. Indeed, customers usually accept a noisy and quite long engine restart when it happens only one time at the kick-off. However, for hybrid vehicles, an inaudible and quick restart is required because it happens without any drivers' demand and thus it may disturb them. In this paper, we focused on NVH analysis of engine restart sequence with conventional ring gear starter. Some solutions were tested in order to optimize restart duration and noise level. Permanently engaged starter and high power starter are two simple and economical solutions that allow reducing significantly both starter noise level and engine restart duration, which makes this technology acceptable for hybrid vehicles.
AFFI, Sameh
Extended Range Cam Phasing Effects on Engine Stop/Start Quality2014-01-17004/1/2014
Engine stop/start systems are one technology being developed to meet ever tightening fuel economy regulations. Several production vehicles in the market have adopted stop/start systems with 12 volt batteries and enhanced starters. During engine autostart events (restart after autostop), the engine/vehicle vibration may be objectionable to customers. In this paper, the impact of extended range retarded intake cam phasing on first cycle combustion and vehicle vibration during engine autostart is provided. The engine intake cam phasers of a production vehicle were modified so the effective compression during autostart could be set as low as 3.5. Achieving these autostart conditions while maintaining typical cam timing positions under cold start conditions is achievable with an innovative dual park phaser. NVH measurements and engine speed traces indicate that this approach reduced vibration during engine autostart by a measurable amount. Subjective driver feedback was also positive. Cylinder pressure measurements at various intake cam timing settings during autostart indicate that retarded intake cam phaser can reduce the tendency of pre-ignition, reduce peak cylinder pressure, and improve combustion control with retarded spark timing.
Liu, Xiaobing, Nahra, Paul, Strehlau, Anna
Ultra Boost for Economy: Extending the Limits of Extreme Engine Downsizing2014-01-11854/1/2014
The paper discusses the concept, design and final results from the ‘Ultra Boost for Economy’ collaborative project, which was part-funded by the Technology Strategy Board, the UK's innovation agency. The project comprised industry- and academia-wide expertise to demonstrate that it is possible to reduce engine capacity by 60% and still achieve the torque curve of a modern, large-capacity naturally-aspirated engine, while encompassing the attributes necessary to employ such a concept in premium vehicles. In addition to achieving the torque curve of the Jaguar Land Rover naturally-aspirated 5.0 litre V8 engine (which included generating 25 bar BMEP at 1000 rpm), the main project target was to show that such a downsized engine could, in itself, provide a major proportion of a route towards a 35% reduction in vehicle tailpipe CO2 on the New European Drive Cycle, together with some vehicle-based modifications and the assumption of stop-start technology being used instead of hybridization. In order to do this vehicle modelling was employed to set part-load operating points representative of a target vehicle and to provide weighting factors for those points. The engine was sized by using the fuel consumption improvement targets and a series of specification steps designed to ensure that the required full-load performance and driveability could be achieved. The engine was designed in parallel with 1-D modelling which helped to combine the various technology packages of the project, including the specification of an advanced charging system and the provision of the necessary variability in the valvetrain system. An advanced intake port was designed in order to ensure the necessary flow rate and the charge motion to provide fuel mixing and help suppress knock, and was subjected to a full transient CFD analysis. A new engine management system was provided which necessarily had to be capable of controlling many functions, including a supercharger engagement clutch and full bypass system, direct injection system, port-fuel injection system, separately-switchable cam profiles for the intake and exhaust valves and wide-range fast-acting camshaft phasing devices. Testing of the engine was split into two phases. The first usied a test bed Combustion Air Handling Unit to enable development of the combustion system without the complication of a new charging system being fitted to the engine. To set boundary conditions during this part of the programme, heavy reliance was placed on the 1-D simulation. The second phase tested the full engine. The ramifications of realizing the engine design from a V8 basis in terms of residual friction versus the fuel consumption results achieved are also discussed. The final improvement in vehicle fuel economy is demonstrated using a proprietary fuel consumption code, and is presented for the New European Drive Cycle, the FTP-75 cycle and a 120 km/h (75 mph) cruise condition.
Turner, J.W.G., Popplewell, A., Patel, R., Johnson, T.R., Darnton, N.J., Richardson, S., Bredda, S.W., Tudor, R.J., Bithell, C.I., Jackson, R., Remmert, S.M., Cracknell, R.F., Fernandes, J.X., Lewis, A.G.J., Akehurst, S., Brace, C.J., Copeland, C., Martinez-Botas, R., Romagnoli, A., Burluka, A.A.
A System for Capturing and Monitoring Machine Breakdown in Shop Floor Using Open Source Software for Improved Productivity2014-01-02944/1/2014
The machine breakdown occurrences in the shop floor of the manufacturing facilities of Ashok Leyland, were captured into the Enterprise Resource Planning (ERP) system with significant time delay. This affected the overall productivity of the shop floor lines. Hence, there was a need to deploy a computer based application with a simple Graphical User Interface (GUI) in the shop floor, to capture breakdown and update the ERP system accordingly. This application was meant for use by the shop floor associates, who come to know of the machine breakdown occurrences first. Also, there was a need for the managers at various levels to monitor the breakdowns, to ensure their timely closure. To fulfil these requirements, the in-house IT resources were sought after by the plant maintenance group. Free and Open Source Software (FOSS) was identified for application development and deployment. FOSS aids in significant cost savings, as there is no license cost involved in application development. The selection of open source software was done according to the design requirements of respective applications. Consequently, Java was identified for developing the breakdown capturing application at the shop floor and Hyper Text Markup Language (HTML), Javascript, Cascading Style Sheet (CSS) was identified for developing the breakdown monitoring application. This paper explains the design and functionality of the breakdown capturing and monitoring applications and their integration with the ERP system. It also presents the estimated cost savings to the company, due to in-house application development using FOSS.
Natarajan, Ramya, Swaminathan, Ganesan, Ramanathan, Shanmugasundaram
Development of Stop/Start Engine Combustion and Restart Control for Gasoline Direct Injection Automatic Transmission Application2014-01-17474/1/2014
Stop/Start technology for conventional automatic transmissions has recently received considerable attention in the automotive industry due to the potential fuel economy, and CO2 emission reduction, benefit at minimal cost. Stop/Start was first developed for manual transmission applications in the EU and Japanese markets. When stop/start is applied to any automatic transmission powertrain the powertrain control challenge is to restart the engine in a manner that simultaneously minimizes the delay in transferring torque to the driven wheel(s) and provides a consistently smooth launch feel with low NVH. It has recently been shown that stop/start can be added to a gas engine powertrain with a conventional torque converter automatic transmission while achieving the desired launch characteristics with minimal change to the powertrain hardware and cost. This paper describes some of the powertrain control challenges that were addressed in the development of a stop/start system for conventional torque converter based automatic transmission applications. In particular the paper describes the stop/start restart engine and transmission characteristics that need to be addressed and provides a detailed description of the gasoline direct injection engine combustion and restart controls that were developed to support the goal of delivering consistently smooth and fast launch performance.
Gibson, Alex O., VanDerWege, Brad, Wooldridge, Steven, Moilanen, Peter C., Lee, Seunghoon
Start/Stop Strategies for Two-Wheelers in the Emerging Markets2013-32-912510/15/2013
Fuel economy of two-wheelers is an important factor influencing the purchasing psychology of the consumer within the emerging markets. Additionally, air pollution being a major environmental topic, there is a rising concern about vehicle emissions, especially in the big cities and their metropolitan areas. Potentially, the relatively expensive engine management systems are providing more features and value in comparison to the carburettor counterpart. The combustion system analysis is carried out on a 125 cm3 motorcycle engine and the subsequent numerical simulation comparing the carburettor and the Electronic (Port) Fuel Injection which provides a basis to establish the fuel consumption benefit for the electronic injection systems [1]. In order to add more flexibility to the engine management systems and provide additional fuel economy benefit the following strategies were numerically simulated and later validated on a chassis dynamometer: 1 Start/Stop: Engine is switched off at a stop while neutral gear is selected. 2 Stop-in-gear: Engine is switched off at a stop in any gear. 3 Idle Coasting: Engine is idling but disengaged from the transmission during coasting. 4 Start/Stop Coasting: Engine is switched off and decoupled from the transmission during coasting. Simulation and dynamometer measurements are obtained based the same implementation of test cycles, which are, the Indian Drive Cycle (IDC) and the World Motorcycle Test Cycle (WMTC), urban part 1. Both cycles represent urban driving patterns, which are very common for two-wheeled transportation within the dynamically growing cities of the emerging markets. The resulting fuel efficiencies were compared to a stock bike configuration - a motorcycle without any of the above mentioned Start/Stop strategies, but with Electronic (Port) Fuel Injection.
Heinzmann, Bernd, Scholz, Simon, R, Pramod, Anantha, Prashanth
Mode Transition Dynamic Control for Dual-Motor Hybrid Driving System2013-01-248710/14/2013
Coordinated control of mode transition is an important part of the multi-mode hybrid vehicles' control strategy, combined with a vehicle torque distribution strategy to realize an optimal working condition of the power sources, as well as achieve smooth mode switching. This paper builds hybrid electric vehicle driveline dynamics model and depth analyzes drive mode transition process, coordinated control methods were provided to solve three types of mode switching, neural network algorithm was provided to estimate the engine torque. The results show that coordinated control can reduce torque fluctuations and decrease jerk during the transition of different modes to improve the vehicle drivability.
Jun, Wang, Wang, Qing-nian, Wang, Peng-yu, li, Li
Integration of Engine Start/Stop Systems with Emphasis on NVH and Launch Behavior2013-01-18995/13/2013
Automatic engine start/stop systems are becoming more prevalent and increasing market share of these systems is predicted due to demands on improving fuel efficiency of vehicles. Integration of an engine start/stop system into a “conventional” drivetrain with internal combustion engine and 12V board system is a relatively cost effective measure to reduce fuel consumption. Comfort and NVH aspects will continue to play an important role for customer acceptance of these systems. Possible delay during vehicle launch due to the engine re-start is not only a safety relevant issue but a hesitating launch feel characteristic will result in reduced customer acceptance of these systems. The engine stop and re-start behavior should be imperceptible to the driver from both a tactile and acoustic standpoint. The lack of masking effects of the engine during the engine stop phases can cause other “unwanted” noise to become noticeable or more prominent. Other comfort related criteria like a stable 12V board supply during the engine start phase or A/C usage during the engine stop phase need to be considered as well. This paper provides an overview of start/stop systems and starter concepts. The requirements for different transmission types and the associated start/stop challenges are described. The phases of an engine start are described in detail, and their influence on the vehicle vibration investigated. NVH related metrics for describing the engine start/stop and vehicle launch are introduced. Key design parameters of the powertrain and driveline on the start/stop NVH behavior are studied. In addition, the impact of engine start on the vehicle's launch behavior is analyzed. Comparisons of different start/stop systems are conducted and results from case studies on the influence to launch delay and “change-of-mind” engine restart are provided. Finally, the effect of missing masking noise during the engine stop phases is discussed.
Wellmann, Thomas, Govindswamy, Kiran, Tomazic, Dean
Vehicle System Control for Start-Stop Powertrains with Automatic Transmissions2013-01-03474/8/2013
The 2013 Ford Fusion will be launched with an optional automatic engine start-stop feature. To realize engine start-stop on a vehicle equipped with a conventional powertrain, there are two major challenges in the vehicle system controls. First, the propulsive torque delivery from a stopped engine has to be fast. The vehicle launch delay has to be minimized such that the corporate vehicle attributes can be met. Second, the fuel economy improvement offered by this technology has to justify the cost associated with it. In pursuing fuel economy, the driver's comfort and convenience should be minimally impacted. To tackle these challenges, a vehicle system control strategy has been developed to accurately interpret the driver's intent, monitor the vehicle subsystem's power demands, schedule engine automatic stop and re-start, and coordinate the fast and smooth torque delivery to the wheels. Vehicle tests have shown that the start-stop feature provides a seamless stop-start operation while introducing minimal intrusion to the driving experience. The start-stop technology improves fuel economy by 3.5% on average.
Wang, Xiaoyong, McGee, Ryan, Kuang, Ming
System Simulation and Analysis of EPA 5-Cycle Fuel Economy for Powersplit Hybrid Electric Vehicles2013-01-14564/8/2013
To better reflect real world driving conditions, the EPA 5-Cycle Fuel Economy method encompasses high vehicle speeds, aggressive vehicle accelerations, climate control system use and cold temperature conditions in addition to the previously used standard City and Highway drive cycles in the estimation of vehicle fuel economy. A standard Powersplit Hybrid Electric Vehicle (HEV) system simulation environment has long been established and widely used within Ford to project fuel economy for the standard EPA City and Highway cycles. Direct modeling and simulation of the complete 5-Cycle fuel economy test set for HEV's presents significant new challenges especially with respect to modeling vehicle thermal management system and interactions with HEV features and system controls. It also requires a structured, systematic approach to validate the key elements of the system models and complete vehicle system simulations. This paper describes a methodology developed at Ford for system simulation and analysis of EPA 5-Cycle fuel economy for powersplit HEV's. Important newly developed elements of the vehicle system models are explained including the modeling of vehicle and engine controls and the procedures of running simulations in accordance with 5-Cycle fuel economy test procedures. Examples of using the system simulation for control calibration optimization to balance 5-Cycle FE and other vehicle attributes are presented. Finally, the paper describes a process for verifying and maintaining the accuracy of the HEV system models over the course of a production vehicle program.
Meng, Yan, Jennings, Mark, Schwartz, William, Tsou, Poyu
Capacitive Humidity Sensors Using Highly Durable Polyimide Membrane2013-01-13374/8/2013
Humidity sensors used in automatic windshield defogging controls contribute to the improvement of fuel consumption. The optimum control of air conditioning systems can be realized by adding humidity information to conventional systems which have used only temperature information. While resistive humidity sensors have been widely used, their sensing range and responsiveness are observed as issues. Resistive sensors cannot function at a humidity range of around 100% RH as well as at a low temperature range, and have a low response rate to sudden changes in humidity. It is considered that resistive humidity sensors will be replaced with capacitive ones which have a wide sensing range and high responsiveness. However, since capacitive sensors use macromolecule organic materials for their humidity sensing membranes, characteristic changes caused by two factors in a high temperature and high humidity environment are concerns: the deterioration of the membrane itself, and the decrease of the adhesive strength between the membrane and the underlying layers. This paper describes a newly developed capacitive humidity sensor with high durability by suppressing hydrolysis and swelling of membranes which cause characteristic changes in a high temperature and high humidity environment. The main development processes are selection of polyimide as a basic organic material, the addition of fluorine atoms of hydrophobic molecules, the extension of the molecular repeat units and the formation of the cross-linked structure to molecular ends. In addition, silane coupling agents is used to increase the adhesive strength of the membrane, thus realizing capacitive humidity sensors for automobile use.
Niimi, Naohisa, Yoshida, Takahiko, Isogai, Toshiki
Real-Time Optimal Energy Management of Heavy Duty Hybrid Electric Vehicles2013-01-17484/8/2013
The performance of energy flow management strategies is essential for the success of hybrid electric vehicles (HEVs), which are considered amongst the most promising solutions for improving fuel economy as well as reducing exhaust emissions. The heavy duty HEVs engaged in cycles characterized by start-stop configuration has attracted widely interests, especially in off-road applications. In this paper, a fuzzy equivalent consumption minimization strategy (F-ECMS) is proposed as an intelligent real-time energy management solution for heavy duty HEVs. The online optimization problem is formulated as minimizing a cost function, in terms of weighted fuel power and electrical power. A fuzzy rule-based approach is applied on the weight tuning within the cost function, with respect to the variations of the battery state-of-charge (SOC) and elapsed time. Comparing with traditional real-time supervisory control strategies, the proposed F-ECMS is more robust to the test environments with rapid dynamics. The proposed method is validated via simulation under two transient test cycles, with the fuel economy benefits of 4.43% and 6.44%, respectively. The F-ECMS shows better performance than the telemetry ECMS (T-ECMS), in terms of the sustainability of battery SOC.
Zhao, Dezong, Stobart, Richard
Battery Development for Stop-Start Application in Brazilian Market2013-01-15264/8/2013
There is a growing worldwide concern regarding the environmental aspects related to the performance of a corporation and its products, whether by consumer demand or government requirements. The constant pressure for innovations and improvements related to sustainable development are current issues in everyday life of any institution that seeks to consolidate a position of acceptance and competitiveness in the global market. The automotive industry is one of the markets more involved and challenged to the demand of the environmental requirements in regards the limits of pollutant emissions and consequently fuel consumption. The European and North America vehicles already have more electrical content inside (either related to safety and comfort or even needs related to weather), which results in significantly higher consumption levels than traditionally observed in Brazil's application. This divergence challenges the Brazilian automakers and their suppliers to develop appropriate and local solutions to the demands of emerging markets. This paper aims to present the studies performed with several Lead Acid battery technologies available for application in Stop-Start vehicles in the Brazilian market. Brazil is the largest automobile market in Latin America and is positioned as 4th largest in the world market (according to 2011, Jatto Dynamics). With significant growth prospects in the coming years, Brazil has consolidated not only as consumers, but as reference in development of solutions to suit the reality of emerging countries. The Brazilian environmental regulations trends to international level, this challenges the automakers to adopt new emerging technologies and adapts others to ensure a good balance of cost-benefit.
Soeiro, Luiz, Cyrne, Luciano, Figueiredo, Leandro, LaRochelle, Christopher, Tsurumaki, Maumi
Virtualization Technology and Using Virtual CPU in the Context of ISO26262: The E-Gas Case Study2013-01-01964/8/2013
A new development environment is required where conflict between control systems is minimized, where processing can be executed while maintaining independence between systems, and where quality can be assured easily. This environment must enable flexibility in software layouts to accommodate software changes during the development process and the parallel development of multiple derivative systems. We have developed virtualization technology (virtual CPU), which allows the execution of system control with a single CPU without conflict between systems. An outstanding virtual CPU architecture that we have developed allows us to execute multiple real-time control tasks with the hardware scheduler, and we have developed hardware that extends the management of address space and interrupt handling, making it possible for a single CPU to be configured as multiple CPUs. Also, we have implemented a bus system that reduces interference between threads. By combining the above three technologies, a single CPU can be used as multiple CPUs, and by operating different OSs on each virtual CPU, independent control systems can be executed together. As an application, we focused on the ISO26262-compliant E-Gas monitoring concept, and implemented the E-Gas architecture using virtual CPUs. We analyzed the ASIL level (ASIL B, ASIL C, and ASIL D) while comparing the E-Gas architecture implemented in virtual CPUs with the standard E-Gas architecture, the E-Gas architecture implemented in a dual core lock-step microcomputer and implemented in a multi-core microcomputer. We have also compared the impact on the virtual CPUs based E-Gas architecture of different types of HW-based safety mechanisms, both in terms of safety properties and costs (silicon area, memory size and performance). We explored a method of applying case studies to the three-level concept (Level 1, Level 2, and Level 3) while achieving ASIL levels. Also, we are using a hypervisor to analyze the effectiveness of the isolation of the monitoring methods. The paper will show in detail the ISO26262 requirements (both in terms of HW, SW and development process, including tools) to be fulfilled by such virtual CPU architecture and which are the HW or SW safety mechanisms and verification measures to be considered. The paper will address key issues like interference freeness, guarantee of task separation, permanent and transient failures coverage, avoidance of dependent failures between the different E-Gas levels and hypervisor safety architecture.
Niimi, Yukihide, Ono, Takayuki, Arai, Soichiro, sugimoto, Hideki, Mariani, Riccardo
Lead-Acid State of Charge Estimation for Start-Stop Applications2013-01-15324/8/2013
Start-stop, aka engine-stop or idle-stop, technologies are increasingly being applied to automotive vehicles to increase fuel economy. Start-stop vehicles turn off the engine during periods of zero speed and/or during prolonged coast down. During engine-stop, the vehicle electronics are powered solely by the battery. To replenish the battery, the battery needs to be recharged. In typical ICE vehicles, the battery is continuously charged. However, fuel economies can be improved if strategic charging of the battery can be achieved through selective charging through the alternator or through regenerative braking. To optimize fuel economy, an accurate estimation of the battery state of charge (SOC) during vehicle operation is required. Although state of charge estimation has mainly focused on Li-ion batteries, lead-acid batteries may be used successfully in start-stop applications. However, SOC estimation for lead-acid batteries is particularly difficult due to side reactions and losses during charging, particularly at high SOC. This is a highly nonlinear function and requires special attention. To estimate the battery SOC, an equivalent-circuit lead-acid battery model is used to simulate the battery dynamics. This model incorporates losses associated with top charging which can affect the battery SOC estimation. In addition, parameter estimation techniques are utilized to identify the dynamic model parameters. Through this research, an online adaptive battery model can be used to estimate the lead-acid battery state of charge for start-stop applications, where the charging patterns may affect the SOC estimation.
Le, Daniel, Sisk, Brian
Control Strategy Research of Engine Smart Start/Stop System for a Micro Car2013-01-05854/8/2013
This paper investigates the control strategy of engine smart start/stop system, and develops the simulation model of the micro car equipped with smart start/stop system in Matlab/Simulink environment. The schematic and the starting process dynamics of the engine smart start/stop system are analyzed. The simulation results of the fuel economy between the baseline vehicle and the vehicle after installation of smart start/stop system are discussed using Matlab and ADVISOR software co-simulation in the NEDC driving cycle. Finally the test of engine start and the emissions test of the micro car equipped with smart start/stop system are conducted using standard chassis dynamometer. The results indicate that the engine of the micro car can be automatically shut off as it meets the conditions of engine automatic stop. The 100-kilometer fuel consumption of the micro car equipped with start/stop system decreases by 3.63% compared to that of the baseline vehicle, and the test result of the fuel saving ratio is consistent with the simulation result. The HC, CO and NOx emission results of the micro car equipped with smart Start/Stop system are 0.047 g/km, 0.542 g/km and 0.035 g/km, respectively. And the emissions are much lower than those of the Euro - emission limits.
Chen, Hanyu, Zuo, Chengji, Yuan, Yinnan
Dynamic Vehicle Powertrain Model Development and Hardware-in-the-Loop Simulator for Developing and Measuring Fuel Efficient CO 2 Reducing Technologies2013-01-03554/8/2013
Current significant challenges in the automotive industry for increasing fuel economy and reducing CO₂ emissions remain with traditional combustion engines. Moderately small increases in fuel efficiency lead to major reductions in CO₂ emissions, primarily due to large production volumes utilizing incremental fuel saving technologies. Enhancements of today's vehicle powertrains, including micro-hybrids and mild-hybrids with stop-start systems, and coasting and energy recuperation have shown a positive cost benefit and shorter payback period. This is identified when the technology is compared to more complex and expensive HEVs (Hybrid Electric Vehicles) and BEVs (Battery Electric Vehicles). This paper describes the development of a baseline conventional vehicle model for estimating fuel savings and CO₂ reduction; it provides a benchmark for the development of fuel saving energy management technologies such as stop-start, coasting, and dual voltage architecture with regenerative braking and "on-demand" fuel senders. It will be shown that a stop-start system will provide a simulated 2.9% FE (Fuel Economy) benefit for the EPA unadjusted combined city/highway driving cycles. Also enhanced stop-start with aggressive coasting with engine-off (≺100 km/hr) provides an additional benefit of 7.1%. In addition, this paper describes a case study for the development of a HIL (Hardware-In-the-Loop) simulator which makes use of the conventional baseline model. The HIL system measures fuel savings of replacing a "100% driven" fuel system with an "on-demand" fuel delivery system. The case study will show a 40% CO₂ reduction over "100% driven" DC pump with a DC "on-demand" pump and an additional 22% CO₂ reduction for the BLDC "on-demand" pump for the EPA city/highway driving cycles using a Mini Cooper vehicle model.
Brown, Alan, Kotori, Doris
Standard Electrical and Logical Interface for Airborne Fuzing SystemsAS5716A (Current)12/3/2012
This interface standard applies to fuzes/fuzing systems (referred to as fuzing system hereafter) in airborne weapons that use a MIL-STD-1760 type interface. It defines the powers, the discrete signals and the serial data interface for the communications at the interface between the fuzing system and the remainder of the weapon, including the weapon control unit. The Class 1 interface is an electrical only interface that facilitates use of MIL-STD-1760 type platform store interfaces for the fuze to monitor intentional release and defines the fuze interface bus communications protocol to allow sending and receiving data from fuzing systems. Class 2 interfaces add a defined connector and additional interfaces to facilitate the exchange of compatible fuzing systems. Class 3 interfaces add further interface definitions to facilitate the exchange of AS5680A compatible fuzing systems components. The bus communications protocol provides a means by which the weapon may set mission parameters within the fuzing system main housing and in other devices external to the fuzing system main housing. The standard also defines the target detection signal to be provided by a target detection device external to the fuzing system. This standard does not address the mechanical interfaces to target detection devices or to other sensors that are external to the fuzing system main housing.
AS-1B Aircraft Store Integration Committee
Items per page:
1 – 50 of 90