Advanced Vehicle Control Systems (AVCS)

The status of plans and projects for intelligent vehicle-highway systems (IVHS) in Europe, Japan, and the US is examined. The four broad areas covered by IVHS are described. They are advanced traffic management systems. advanced traveler information systems commercial vehicle operations systems, and advanced vehicle control systems. A variety of projects in Europe, Japan, and the US which aim at proving the feasibility and practicality of IVHS are described. Socioeconomic factors then could delay or even arrest the development of IVHS are examined.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Intelligent Vehicle/Highway Systems (IVHS) is a multi-year research/demonstration program which aims at improving the vehicle/highway system operation and management techniques for the post-interstate construction era. The authors first describe the framework of IVHS, which as four major components: (1) advanced traffic management system (ATMS); (2) advanced driver information system (ADIS); (3) commercial vehicle operations (CVO); and (4) advanced vehicle control systems (AVCS). The ATMS related research and development plans to support the real-time traffic management systems and control strategies are considered. The state-of-the-art traffic engineering modeling software is reviewed. The discussion centers around the TRAF system, a family of microscopic and macroscopic traffic simulation software models for surface streets, freeways, and corridor networks. The gap between the capabilities provided by the current traffic modeling software and the functional requirement of the IVHS traffic models is also addressed. >

Intelligent Vehicle-Highway Systems (IVHS) is a major U.S. Department of Transportation initiative to improve the safety and efficiency of our nation's highways. IVHS includes five related components: Advanced Traffic Management Systems (ATMS); Advanced Traveler Information Systems (ATIS); Commercial Vehicle Operations (CVO); Advanced Vehicle Control Systems (AVCS); and, Advanced Public Transportation Systems (APTS). Although the Federal Highway Administration has initially chosen to address each of these components separately, a number of issues are shared by all components. One critical common element deals with the capabilities of the humans in the system. Appropriate guidelines that consider the needs and capabilities of operators, maintainers, and users will be critical for efficient functioning of each system. Efforts are underway to define and resolve critical human factors issues related to IVHS components. This symposium addresses four of the five more highway related IVHS components. For each of these components, presenters will define the key engineering characteristics, hypothetical scenarios that focus on human-system interfaces, and examples of human factors issues that must be considered in the design of IVHS systems.

&lt;div class="htmlview paragraph"&gt;Computer simulation and real-time, interactive approaches for analysis, interactive driving simulation, and hardware-in-the-loop testing are finding increasing application in the research and development of advanced automotive concepts, highway design, etc. Vehicle dynamics models serve a variety of purposes in simulation. A model must have sufficient complexity for a given application but should not be overly complicated. In interactive driving simulation, vehicle dynamics models must provide appropriate computation for sensory feedback such as visual, motion, auditory, and proprioceptive cuing. In stability and handling simulations, various modes must be properly represented, including lateral/directional and longitudinal degrees of freedom. Limit performance effects of tire saturation that lead to plow out, spin out, and skidding require adequate tire force response models. Additional steering and braking subsystem characterizations are necessary to represent important handling and stability requirements. Steering compliance and appropriate tire aligning torque effects provide a significant component of understeer. Front-to-rear brake proportioning plays a significant role in limit performance directional stability, including the effects of nonlinear brake pressure proportioning valves.&lt;/div&gt; &lt;div class="htmlview paragraph"&gt;This paper summarizes vehicle dynamics model requirements for various classes of interactive and computer simulations. General formulations include sets of force and moment equations, with subsidiary equations for effects such as tire force response, antilock, traction control, four-wheel steering, and other advanced vehicle control systems (AVCS). Examples of simple and complex models will be given, including validation methods, for vehicle and driver models.&lt;/div&gt;

Advanced Traffic Management Systems (ATMS) are those components of Intelligent Vehicle Highway Systems (IVHS) that integrate traffic detection, communication, and control functions to be responsive to dynamic traffic conditions and increase the efficiency of existing traffic networks. ATMS provide the management foundation that will enable and integrate other IVHS components such as Commercial Vehicle Operations, Advanced Traveler Information Systems, Advanced Vehicle Control Systems, and Advanced Public Transportation Systems. This paper defines Advanced Traffic Management Systems. It also describes the functions that may take place within an ATMS-class Traffic Management Center (TMC), a scenario that a future TMC operator may encounter, and some of the human factors issues that must be addressed in the design of an ATMS-class TMC.

&lt;div class="htmlview paragraph"&gt;This paper reports an analysis of potential costs and revenues to apply road pricing in Melbourne. Objectives of road pricing are assumed to be reduced peak period congestion and raising of funds for transport infrastructure.&lt;/div&gt; &lt;div class="htmlview paragraph"&gt;The analysis provides a broad understanding of opportunities for Intelligent Vehicle Highway Systems (IVHS) to be applied to road pricing; using Melbourne as a test case.&lt;/div&gt; &lt;div class="htmlview paragraph"&gt;Road pricing can take many forms from simple flat annual charges with fuel consumption based variable charges through to systems which charge vehicle owners according to actual road use.&lt;/div&gt; &lt;div class="htmlview paragraph"&gt;IVHS developments will be the key to the implementation of socially acceptable systems which charge according to actual use - or a form of charging which partially meets this objective.&lt;/div&gt; &lt;div class="htmlview paragraph"&gt;As pressure on road funds increases over the next decade, there is likely to be greater emphasis on the use of IVHS technologies to change the way in which road infrastructure is managed.&lt;/div&gt;

&lt;div class="htmlview paragraph"&gt;Video surveys are being used in Doncaster to provide an up-to-date inventory of the highway network and street furniture. The techniques being used are closely related to those under development for the collection of network attribute data for Advanced Transport Telematics (ATT) / Intelligent Vehicle Highway Systems (IVHS) systems, in particular for route guidance and navigation systems.&lt;/div&gt; &lt;div class="htmlview paragraph"&gt;The success of systems such as Autoguide, EURO-SCOUT (formerly called ALI-SCOUT), CARIN, Travelpilot and dual-mode route guidance will be critically dependent upon the quality of the data on which navigation and routeing recommendations are based. Experience, in London and Berlin in particular, has shown that the information presented to the driver throughout his journey needs to be accurate, precisely timed and in a large number of cases specifically tailored to the details of individual junction layouts. It is not possible to provide the quality of data necessary for system acceptance without detailed surveys of the roads on which guidance is to be given.&lt;/div&gt; &lt;div class="htmlview paragraph"&gt;Video survey techniques offer the flexibility to view road and junction layouts in a controlled office environment, minimising the need for costly re-surveying, and significantly improving data quality and consistency. The system in use in Boncaster is providing the basis of an innovative methodology in which in-vehicle computers are interfaced with navigation systems and professional video techniques.&lt;/div&gt; &lt;div class="htmlview paragraph"&gt;This results in the integration of the digital map base with the information required to generate the vitally important turning recommendations for the driver and the accurate data necessary for successful map-matching.&lt;/div&gt; &lt;div class="htmlview paragraph"&gt;The paper presents results and conclusions from Doncaster. It reviews the need for this type of accurate data, describes experiences in existing trials of ATT/IVHS systems, analyses developments in digital map creation techniques and presents the context into which the new generation of data collection methodology will be integrated.&lt;/div&gt;

Lateral distance measurement system for AVCS (advanced vehicle control systems) has been developed in the various countries. This paper describes a lateral distance measurement system using spread spectrum (SS) technique. Our method does not require significant infrastructure investment because it is based on the reflected signal from the guardrails currently installed on many roads. The range resolution of SS radar is generally equal to the length of one chip because it is based on the correlation using chip synchronization. We propose a short range measurement system utilizing the slope of the correlation function of m-sequence as an application of SS technique and indicate the results of the experiment.

Current research on advanced vehicle control systems (AVCS) emphasizes the regulation of individual vehicles from a vehicle-level point of view. To improve the roadway operational efficiency, however, it is necessary to coordinate the operations of the vehicles on the highway. In this paper, a highway-level control algorithm is proposed which optimizes the traffic flow from a system-level viewpoint. The highway is divided into cells. The density and average speed of vehicles in these cells are assumed to be measured in real-time. Desired vehicle acceleration and lane change commands are assumed to be transmitted through communication devices to the vehicles, which optimize the traffic flow over the whole highway section. The system-wide traffic is optimized by using the downstream traffic status as the “preview” information for upstream traffic regulation. Numerical simulations were performed to validate the effectiveness of the proposed control algorithms.

Recently electric power steering system has been developed. Steer-by-wire system has big advantages of packaging flexibility, advanced vehicle control system, and superior performance. Steer-by-wire system has no mechanical linkage between the steering gear and the steering column. It is possible to control the steering wheel and the front-wheels steering independently. The active steering which reduce the difference between actual and estimated vehicle yaw rate can be realized. Since the information from the steering wheel is important for the driver to know the road condition, tire force should be fed back to the steering wheel. But unexpected disturbance is better suppressed without affecting to the steering wheel. Based on estimating the vehicle side slip angle from the internal sensor response, the tire self-aligning torque can be estimated. This torque is fed back to the steering wheel so that the driver can know the road condition. In this paper, we propose the method to control the vehicle yaw rate using steer-by-wire system, also disturbance applied to the front tires is suppressed by disturbance observer without affecting to the steering wheel. Numerical simulations are carried out to show the validity of the proposed method.

Vehicle Side Slip Angle Observation with Road Friction Adaptation

Applications of inter-vehicle communications to driver assistance system

&lt;div class="section abstract"&gt;&lt;div class="htmlview paragraph"&gt;Developing a knowledge-based predictive driver-aid system requires a strategy that meets the needs and goals, as well as rigorous methods. This paper presents the strategy adopted and the first results obtained in the development of the Navigation Aided Intelligent Cruise Control (N.A.I.C.C.) system. Once the vehicle is located on the route, this new copilot can: &lt;ol class="list nostyle"&gt; &lt;li class="list-item"&gt; &lt;span class="li-label"&gt;1.&lt;/span&gt; &lt;div class="htmlview paragraph"&gt;define the travel direction and the vehicle speed,&lt;/div&gt;&lt;/li&gt; &lt;li class="list-item"&gt; &lt;span class="li-label"&gt;2.&lt;/span&gt; &lt;div class="htmlview paragraph"&gt;determine the distance to the next bend and its characteristics,&lt;/div&gt;&lt;/li&gt; &lt;li class="list-item"&gt; &lt;span class="li-label"&gt;3.&lt;/span&gt; &lt;div class="htmlview paragraph"&gt;predict the optimal speed to negotiate the next bend considering the road profile, the constraints given by the driver and the information provided by the sensors mounted on the vehicle.&lt;/div&gt;&lt;/li&gt;&lt;/ol&gt;&lt;/div&gt;&lt;div class="htmlview paragraph"&gt;Then, used in the warning mode (“Driver Alarm Mode”), N.A.I.C.C. informs the driver of the danger of the situation (excessive speed) or, in the intervention mode (“Velocity Control Mode”), N.A.I.C.C. adapts the speed to the predicted reference. In this latter operating mode, N.A.I.C.C. can be considered as an advanced intelligent cruise control system. Real experiments were carried out with the laboratory test car to validate each module described.&lt;/div&gt;&lt;/div&gt;

&lt;div class="htmlview paragraph"&gt;In order to allow continued production of the AM General Optimizer 6500 during MY 2007 through 2010 this IDI engine (Indirect Injection - swirl chamber) requires sophisticated aftertreatment controls while maintaining its fuel economy and durability.&lt;/div&gt; &lt;div class="htmlview paragraph"&gt;The main purpose of the development program was to retain the relatively inexpensive and simple base engine with distributor pump and waste-gated turbocharger, while adding hardware and software components that allow achievement of the phase-in emission standards for 2007 through 2010. The aftertreatment system consists of Diesel Oxidation Catalyst (DOC), NOx Adsorber Catalyst (or DeNOx Trap - DNT) and Diesel Particle Filter (DPF). In addition to the base hardware, an intake air throttle valve and an in-exhaust fuel injector were installed.&lt;/div&gt; &lt;div class="htmlview paragraph"&gt;The presented work will document the development process for a 2004 certified 6.5 l IDI heavy-duty diesel engine to comply with the 2007 heavy-duty emission standards. The system architecture evaluation proved to be one of the key development items that determined the packaging in the projected vehicle platform. Based on the temperature profile, it was found that the DOC-DPF-DNT configuration is mandatory to achieve NOx and NMHC standards. The development of the DPF regeneration, deNOx and deSOx strategy were strongly based on a multi-variable controls approach using temperature or lambda interventions depending on the system request.&lt;/div&gt; &lt;div class="htmlview paragraph"&gt;Development results for the HD-FTP and SET (13-mode Supplemental Emissions Test) show that the tailpipe emissions and the NTE (not-to-exceed) limits can be met with a considerable safety margin allowing reasonable degradation factors.&lt;/div&gt; &lt;div class="htmlview paragraph"&gt;The integrated system was installed in a project vehicle and underwent multiple climate testing trips focusing on DPF regeneration under cold ambient, high altitude and hot ambient conditions.&lt;/div&gt; &lt;div class="htmlview paragraph"&gt;It could be proven that a concept with a comparably cost-effective base engine which does not utilize direct fuel injection, along with an advanced aftertreatment control system, is capable to meet the U.S. 2007-2010 phase-in emission standards.&lt;/div&gt;

&lt;div class="section abstract"&gt;&lt;div class="htmlview paragraph"&gt;Diesel aftertreatment (AT) systems are critical for controlling emissions of CO, HC, NO&lt;sub&gt;X&lt;/sub&gt;, and PM in the on-road transportation sector. Ensuring compliance with regulatory standards throughout the AT system's lifespan requires precise prediction of various degradation mechanisms under real-world operating conditions and mitigating their impact through proper catalyst sizing and advanced controls. In the SwRI A2CAT-II consortium, a medium-duty diesel engine production aftertreatment system was subjected to full useful life aging, involving chemical poisoning with phosphorus (P) and sulfur (S) species, along with hydrothermal aging following the DAAAC protocol. This study was aimed to model and predict the aging trajectory of this production AT system thereby capturing changes in system dynamics under both steady-state and transient conditions. The system, designed to meet the 0.2 g/bhp-hr standard, comprised a Diesel Oxidation Catalyst (DOC), Diesel Particulate Filter (DPF), Selective Catalytic Reduction (SCR), and Ammonia Slip Catalyst (ASC). It was aged to 3600 hours equivalent to the DAAAC protocol and tested across a series of steady-state and regulatory cycles (HFTP, RMC, and LLC) at degreened, 33%, 66%, and 100% aging points. A linear decrease in system NOx conversion was observed between 0% to 66% aging, followed by a nonlinear drop from 66% to 100%. The cumulative decline in NOx conversion was 0.8%, which could significantly impact systems designed to meet a 0.05 g/bhp-hr target.&lt;/div&gt;&lt;div class="htmlview paragraph"&gt;IntroductionAftertreatment durability demonstration is a mandatory validation exercise for on-road medium and heavy-duty diesel engine certification. This requirement ensures that the emission compliance can be achieved for the intended full useful life (FUL) of the engine system or multiple vehicle families. Conventional Deterioration Factor (DF) approach considers linear effect of sulfur and phosphorous poisoning on the catalysts over the entire useful life based on performance from 33% of aging the catalysts and extrapolating them to FUL. However, based on various studies, the impact of fuel derived Sulfur on diesel aftertreatment components was found to be exponentially significant particularly on the SCR due to the sulfur poisoning effect which require an active means to liberate sulfur to maintain appropriate SCR NOx conversion performance. Phosphorous from lubricating oil is known to adversely affect the activity of the oxidation catalyst in a catalyzed DPF thereby reducing the passive regenerative performance of DPF. For these reasons, an extensive understanding of chemical poisoning (particularly Sulfur and Phosphoros) and hydrothermal aging are warranted to design, validate and demonstrate the durability of aftertreatment components that are subjected to the prolonged chemical exposure.&lt;/div&gt;&lt;div class="htmlview paragraph"&gt;To address the extensive challenges in durability demonstration, the Diesel Aftertreatment Accelerated Aging Protocol, or DAAAC, was developed by Southwest Research Institute as a part of consortium effort that includes input from diesel engine manufacturers [&lt;span class="xref"&gt;1&lt;/span&gt;, &lt;span class="xref"&gt;2&lt;/span&gt;, &lt;span class="xref"&gt;3&lt;/span&gt;]. DAAAC is an accelerated aging cycle developed for each application based on the available field data. It includes the exposure from hydrothermal aging, sulfur and lubricant derived poison at accelerated rates. The protocol also requires the entire aftertreatment system to be aged as a complete system, since the upstream components, such as DOC, can impact the chemical makeup of sulfur derived constituents.&lt;/div&gt;&lt;div class="htmlview paragraph"&gt;The protocol does not introduce chemical constituents not normally observed in the field. The accelerated chemical exposure rate is limited only to a degree that has previously demonstrated successful correlation to normal, unaccelerated aging. The Protocol also requires that chemical aging mechanisms are to be introduced and / or consumed in a manner representative of the engine’s defined consumption pathways. Examples include sulfur exposure via high sulfur fuel or gaseous SO&lt;sub&gt;2&lt;/sub&gt; and oil consumption via pre-combustion / post-combustion pathways. The Protocol also does not introduce chemical components that are not normally present in oil or fuel (other than doping the fuel with higher concentrations of sulfur, but this amount is relatively small). A comprehensive step by step breakdown of DAAAC protocol is presented elsewhere [&lt;span class="xref"&gt;2&lt;/span&gt;].&lt;/div&gt;&lt;div class="htmlview paragraph"&gt;The primary objective of this paper is to disseminate the observation of long-term impacts of chemical poisoning and hydrothermal aging on a production aftertreatment catalyst subjected to FUL DAAAC protocol. The results of this experimental campaign were used to develop and validate a model capable of predicting hydrothermal and chemical aging mechanisms of conventional diesel aftertreatment to optimize long term emissions reduction performance. The paper is divided into following sections: &lt;ol class="list nostyle"&gt;&lt;li class="list-item"&gt;&lt;span class="li-label"&gt;1&lt;/span&gt;&lt;div class="htmlview paragraph"&gt;Introduction: An overview of the system&lt;/div&gt;&lt;/li&gt;&lt;li class="list-item"&gt;&lt;span class="li-label"&gt;2&lt;/span&gt;&lt;div class="htmlview paragraph"&gt;Background: A review of literature in the field of diesel AT aging&lt;/div&gt;&lt;/li&gt;&lt;li class="list-item"&gt;&lt;span class="li-label"&gt;3&lt;/span&gt;&lt;div class="htmlview paragraph"&gt;Test Campaign: Description of experimental setup used for collection of both steady state and transient data.&lt;/div&gt;&lt;/li&gt;&lt;li class="list-item"&gt;&lt;span class="li-label"&gt;4&lt;/span&gt;&lt;div class="htmlview paragraph"&gt;Experimental setup: Description of burner stand used for data collection.&lt;/div&gt;&lt;/li&gt;&lt;li class="list-item"&gt;&lt;span class="li-label"&gt;5&lt;/span&gt;&lt;div class="htmlview paragraph"&gt;Results and Discussion: Description of experimental results followed by discussion about underlying degradation mechanism identified through simulation work.&lt;/div&gt;&lt;/li&gt;&lt;li class="list-item"&gt;&lt;span class="li-label"&gt;6&lt;/span&gt;&lt;div class="htmlview paragraph"&gt;Summary and conclusion&lt;/div&gt;&lt;/li&gt;&lt;/ol&gt;&lt;/div&gt;&lt;/div&gt;