Browse Topic: Stop / start technology

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Smart Stability: Dual-Mode Hill Hold and Parking Brake Strategy in Electric Tractors Using Motor Torque and Electro-Hydraulic Actuation2026-26-02051/16/2026
Operating tractors on Sloped Terrains presents safety challenges, especially during shuttle operations, loader use, or start-stop maneuvers at slopes. Unlike Diesel Counterparts, feedback from the prime mover (Motor) is minimal and silence often masks terrain feedback. Driver response tends to vary, leading to rollback & challenges to safety demanding skill & expertise for safe operation. Based on field observations across Mahindra tractor platforms, we identified start-stop maneuver task to be offloaded from the operator to improve control and consistency and take skill element out of picture. This paper outlines the approach derived based on dual-mode Hill Hold and Parking Brake system, developed using traction motor torque control and SAHR-based hydraulic braking via proportional valves. The VCU works at the heart of this system to dynamically choose between electric and hydraulic modes based on vehicle state, ignition, and motor conditions. Parking brake automation logic has been
M, Rojer, P, Velusamy, Natarajan, Saravanan, devakumar, Kiran, T, Ganesan, sundaram, Pavithra, Muniappan, Balakrishnan
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suppliers, LIN transceiver suppliers, component release engineers, and vehicle system engineers.The term “master” has been replaced by “commander” and term “slave” with “responder” in the following sections.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
An Innovative and Customer Centric Approach on Validating Telematics Based Fleet Optimization Feature for Small Commercial Vehicles2024-26-03781/16/2024
Commercial transportation is the key pillar of any growing economy. Light commercial vehicles are increasing every day to cater the logistics demand, but there is always a gap between customer’s actual and desired operational efficiency. This is because of lack of organized fleet and efficient fleet operation. The major requirement of fleet owners is timely delivery, high productivity , downtime reduction, real time tracking, etc., Automakers are now providing fleet management application in modern LCV to satisfy the fleet operator requirement. However, any feature malfunction, consignment mismatch, wrong notification, missed alerts, etc., can incur huge loss to fleet operator and disrupt the entire supply chain. Hence it is very critical to extensively validate the telematics features in fleet management application. This paper explains the approach for exhaustive validation strategy of fleet management applications (B2B) from end user perspective. An effective test methodology was
B, SAKTHIVEL, Shams, Tausif, Lalasure, Santosh, Karnure, Shabbir Lalaso, Rajakumar, K.
Experimental study on oil dilution under cold starts and its impact on oil quality2022-01-06333/29/2022
Oil dilution caused by fuel and water have been widely reported in modern Turbo-charged Gasoline direct injection (TGDI) engines, especially for those equipped with hybrid electric vehicles (HEVs). However, there is a lack of a systematic investigation on its causes and its impacts on oil quality. In the present study, a group of engine operation points based on the data from drum tests were selected and tested in an engine bench over different durations. The coolant temperature was fixed in each test, ranging from 30℃ to 90℃. Also, the effects of frequent engine start/stop and continuously engine operation were compared. It is found that the oil dilution level by fuel presents a good linear relationship with engine speed, torque and coolant temperature for the given cases while the oil dilution by water is negatively related with engine speed. The frequent start/stop could enhance the oil dilution by water, leading to the oil emulsification. The time for the recovery from the oil
Tan, Zhi, Li, Yanfei, Xu, Hongming, Shuai, Shijin
Application of Electric Cam Phaser System (ECP) for Smooth Engine Starting Behavior in Hybrid Vehicles2021-26-00579/22/2021
In the current situation and upcoming government regulations, hybrid vehicles are very promising in terms of meeting fuel economy and stringent requirements of emission norms. Herein, hybridization will be mostly done with gasoline and CNG vehicles. As a normal practice, engine is switch off at the signal and again restart with engine start-stop technology. So, instances of engine start/stop are increases in hybrid vehicle in comparison with standard IC engine vehicle. In order to achieve smooth engine start, engine starting torque can be optimized by adjusting engine valve timing. As electric cam phaser (ECP) meets valve timing target even before first engine combustion start, this is one of the critical technologies in reducing engine starting torque and time reaching to idle speed. This engine starting strategy also gives benefits in terms of reducing engine start emissions and improving fuel economy. This paper describes selection of electric cam phaser for hybrid vehicle depending
Sheikh, Shabbir, Thoelke, Andreas, Deshmukh, Uday, Rathore, Krishna Kumar
Development of a Novel Dynamically Loaded Journal Bearing Test Rig2021-01-12189/21/2021
In this work, a dynamically loaded hydrodynamic journal bearing test rig is developed and introduced. The rig is a novel design, using a hydraulic actuator with fast acting spool valves to apply load to a connecting rod. This force is transmitted through the connecting rod to the large end bearing which is mounted on a spinning shaft, simulating a crankshaft journal. The hydraulic actuator allows for fully variable load control and can be used to apply either static load in compression and tension or dynamic loading to simulate engine operation. A variable speed electric motor controls shaft speed and is synchronized to the hydraulic actuator motion to accurately simulate loading from each stroke in a four-stroke cycle. In addition to these dynamically loaded cycles, the journal bearing rig is also capable of controlled static loading. This static loading is used to simulate stop/start engine operation. A high precision torque meter enables direct measurements of journal bearing
Michlberger, Alexander, Bachu, Pruthvi, Bitsis, Daniel Christopher
Virtual Platform Development for New Control Logic Concept Test and Validation2021-01-11439/21/2021
As computer-aided engineering software tools advance, more simulation-based processes are utilized to reduce development time and cost. Traditionally, during the development of a new control algorithm dyno or on-road testing is necessary to validate a new function, however, physical testing is both costly and time consuming. This study introduces a co-simulation platform and discusses its use as an improved method of powertrain control logic development. The simulation platform consists of a dynamic vehicle model, virtual road network and simulated traffic objects. Engineers can utilize Matlab/Simulink along with other programs such as PTV Vissim, Tass Prescan, and AVL Cruise to create an integrated platform capable of testing and validating new control strategies. The structure and configuration of this virtual platform is explained in this paper, and an example use case is demonstrated. A driver model was developed to simulate realistic vehicle inputs. Validation of this new driver
Fan, Shihong, Lee, Jason, Sun, Yong, Ha, Jinho, Harber, John
Vibration Analysis of an Electric Vehicle Mounting System under Transient Shock Conditions2021-01-06644/6/2021
Electric vehicle motors have the characteristics of fast torque response, large amplitude, and braking feedback torque. Therefore, the excitation of the electric vehicle powertrain has obvious transient impact characteristics, which put forward new requirements for the design of the mounting system. This article carried out the real vehicle test of rapid acceleration and rapid deceleration. A 12-degree-of-freedom nonlinear dynamic model of the electric vehicle mounting system is established. The model is used to calculate the vibration acceleration of the active side and the passive side of the mount, and compared with the test value to verify the correctness of the simulation model. The impact degree, the maximum pitch angle of the powertrain, and the longitudinal acceleration of the powertrain centroid are used as evaluation indicators to analyze the transient response of the electric vehicle mounting system under rapid acceleration and rapid deceleration conditions. The influence of
Xiao, Bing, Wang, Minghui, Jiang, Yongfeng, Kang, Yingzi
A Control-Oriented Spatially Resolved Thermal Model of the Three-Way-Catalyst2021-01-05974/6/2021
The three-way-catalyst (TWC) is an essential part of the exhaust aftertreatment system in spark-ignited powertrains, converting nearly all toxic emissions to harmless gasses. The TWC’s conversion efficiency is significantly temperature-dependent, and cold-starts can be the dominating source of emissions for vehicles with frequent start/stops (e.g. hybrid vehicles). In this paper we develop a thermal TWC model and calibrate it with experimental data. Due to the few number of state variables the model is well suited for fast offline simulation as well as subsequent on-line control, for instance using non-linear state-feedback or explicit MPC. Using the model could allow an on-line controller to more optimally adjust the engine ignition timing, the power in an electric catalyst pre-heater, and/or the power split ratio in a hybrid vehicle when the catalyst is not completely hot. The model uses a physics-based approach and resolves both axial and radial temperature gradients, allowing for
Lock, Jonathan, Clasen, Kristoffer, Sjoblom, Jonas, McKelvey, Tomas
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
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
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
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
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.
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
Athani, Gopal, Gavarraju, Srinivasa Raju, Jain, Punit, Addala, Shashank, P, Satishkumar
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
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
Zhang, Zhenli, Jin, Zhihong, Watson, Thomas
Real World Driving: Emissions in Highly Congested Traffic2017-01-238810/8/2017
The emissions from vehicles in real world driving are of current concern, as they are often higher than on legislated test cycles and this may explain why air quality in cities has not improved in proportion to the reduction in automotive emissions. This has led to the Real Driving Emissions (RDE) legislation in Europe. RDE involves journeys of about 90km with roughly equal proportion of urban, rural and motorway driving. However, air quality exceedances occur in cities with urban congested traffic driving as the main source of the emissions that deteriorate the air quality. Thus, the emissions measured on RDE journeys may not be relevant to air quality in cities. A Temet FTIR and Horiba exhaust flow measurement system was used for the mass emissions measurements in a Euro 4 SI vehicle. A 5km urban journey on a very congested road was undertaken 29 times at various times so that different traffic congestion was encountered. Each journey was split into ten sections in order that the
Khalfan, Ahmad, Andrews, Gordon, Li, Hu
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
Wellmann, Thomas, Govindswamy, Kiran, Tomazic, Dean
FUNCTIONAL SAFETY-Progressing towards safer mobility17MEIP06_036/1/2017
<![CDATA[Abstract]]> Increasing complexity in E/E architectures poses several challenges to developing comfortable, clean and safe vehicles. This mandates robust processes to mitigate potential hazards due to malfunction of electronic systems throughout the product lifecycle. With the advent of ISO 26262, which provides guidelines for developing safe cars, the process is becoming standardized towards safer mobility. In this paper, the functional safety process is briefly covered and a case study of Hazard Analysis and Risk Assessment for specific E/E system is presented. An in-house tool developed for functional safety process and management also is presented.
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
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
Saavedra, Jose-Guillermo, Makki, Asaad, Cruz, Raciel
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
Naidu, Ashish, Brittle, Peter, Ma, Xiaoyu, Rutter, Brian
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
Khafagy, Hafiz S.
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
Imanishi, Yuto, Tashiro, Naoyuki, Iihoshi, Yoichi, Okada, Takashi
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
Wiechowski, Norbert, Rambow, Thomas, Busch, Rainer, Kugler, Alexander, Hansen, Norman, Kowalewski, Stefan
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
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.
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
Athani, Gopal, Dongare, Kapil, Balusu, Rajesh, Gupta, Subhabrata, Gavarraju, Srinivasa Raju
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
Zhang, Zhenli, Jin, Zhihong, Wyatt, Perry
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
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
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
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
Duan, Chengwu, Samie, Farzad, Hebbale, Kumaraswamy, Li, Dongxu, Lee, Chunhao
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
Nagarajan, Umashankar, Goswami, Ambarish
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.
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
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
Liu, Xiaobing, Nahra, Paul, Strehlau, Anna
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
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
Gibson, Alex O., VanDerWege, Brad, Wooldridge, Steven, Moilanen, Peter C., Lee, Seunghoon
Friction and Wear Reduction of Engine Bearings with Solid Lubricant Overlay2014-01-09554/1/2014
In recent years, engines equipped with idle reduction system for fuel saving have been increased in Europe and Japan. Because of the start-stop frequency increase, correspondingly crankshaft and engine bearing contacts also increase. The friction between shaft and bearing is significant to reduce fuel consumption, and besides it, engine bearing wear tends to increase. Therefore, lower friction with small wear engine bearings are expected. In this paper, new developed engine bearing with solid lubricant overlay and its frictional and wear properties are reported (1). As experimental result, a bearing with MoS2 solid lubricant contained polyamide-imide resin coated overlay proved 40% less coefficient of friction, 25% less starting torque and 65% less bearing wear against conventional aluminum alloy bimetal bearing without overlay under close to the start-stop lubrication conditions by testers. Also diesel engine bench test proved less FMEP.
Chitose, Toshiyuki, Kamiya, Shu, Kabeya, Yasunori, Desaki, Toru
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
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.
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
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
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