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This technical paper collection includes 8 papers from OEMs, suppliers, and academia detailing current brake engineering issues and technology. Topics covered include: NVH, controls, modeling, testing, brake drag, and hardware-in-the-loop evaluations.

This presentation proposes an approach to use ABS wheel speed sensor signals together with other vehicle state information from a brake control module to detect an unbalanced tire or tires in real-time. The proposed approach consists of two-stage algorithms that mix a qualitative method using band-pass filtering with a quantitative parameter identification using conditional least squares. This two-stage approach can improve the robustness of tire imbalance or imbalances. The proposed approach is verified through vehicle testing and the test results show the effectiveness of the approach. Presenter Jianbo Lu, Ford Motor Co.

An electrically-driven, intelligent brake unit has been developed, to be combined with a regenerative braking system in electric vehicles (EVs) and hybrid electric vehicles (HEVs) which went into production in 2010 - 11. The brake pedal force is assisted by an electrically driven motor, without using vacuum pressure, unlike conventional braking systems. The actuator can be implemented to coordinate with a regenerative braking system, and to have adjustable pedal feel through use of a unique pressure-generating mechanism and a pedal-force compensator. In this paper, we describe features of the actuator mechanism and performance test results Presenter Yukio Ohtani, Hitachi Automotive Systems

Real-time simulation of truck and trailer combinations can be applied to hardware-in-the-loop (HIL) systems for developing and testing electronic control units (ECUs). The large number of configuration variations in vehicle and axle types requires the simulation model to be adjustable in a wide range. This paper presents a modular multibody approach for the vehicle dynamics simulation of single track configurations and truck-and-trailer combinations. The equations of motion are expressed by a new formula which is a combination of Jourdain's principle and the articulated body algorithm. With the proposed algorithm, a robust model is achieved that is numerically stable even at handling limits. Moreover, the presented approach is suitable for modular modeling and has been successfully implemented as a basis for various system definitions. As a result, only one simulation model is needed for a large variety of track and trailer types.

Hybrid Electric Drive (HED) provides the potential to improve military vehicle capabilities beyond the well understood fuel economy benefits. Additional HED benefits for military operations can be realized in the areas of mobility, survivability, lethality, power generation and maintainability. General Dynamics Land Systems (GDLS) continues to demonstrate significant advantages that HED can offer to military vehicle platforms. This presentation will focus on the advanced military capabilities provided by HED utilizing in-hub wheel motors and include a summary of GDLS demonstrator vehicles with integrated HED. Presenter Andrew Silveri, GENERAL DYNAMICS LAND SYST

This paper presents a low-cost path for extending the range of small urban pure electric vehicles by hydraulic hybridization. Energy management strategies are investigated to improve the electric range, component efficiencies, as well as battery usable capacity. As a starting point, a rule-based control strategy is derived by analysis of synergistic effects of lead-acid batteries, high efficient operating region of DC motor and the hydraulic pump/motor. Then, Dynamic Programming (DP) is used as a benchmark to find the optimal control trajectories for DC motor and Hydraulic Pump/Motor. Implementable rules are derived by studying the optimal control trajectories from DP. With new improved rules implemented, simulation results show electric range improvement due to increased battery usable capacity and higher average DC motor operating efficiency. Presenter Xianke Lin

The 19 papers in this technical paper collection cover vehicle brake system performance, vehicle brake noise, antilock braking control of electric vehicles, enhanced traction stability control systems, and more.

The 14 papers in this technical paper collection cover brake subsystem performance and their impact on the overall vehicle brake system, electro-mechanical brakes and controls, and vehicle performance and NVH issues.

The 6 papers in this technical paper collection include the following topics: high temperature brake cooling; brake rotors; development of electrically-driven intelligent brake system; ABS stopping distance; static brake testing; and more.

This technical paper collection discusses the latest scientific discovers and technological innovations in brake materials, components, systems, testing, modeling and aftermarket.

The 9 technical papers in this collection cover the evolving demands on brake systems driven by hybrid and electric vehicle architectures are providing opportunity for new component and brake system configurations and a demand for greater integration of the brake control system with overall vehicle controls.

This technical paper collection is focused on vehicle dynamics and controls using modeling and simulation, and experimental analysis of passenger cars, heavy trucks, and wheeled military vehicles. The papers address active and passive safety systems to mitigate rollover, yaw instability and braking issues; driving simulators and hardware-in-the-loop systems; suspension kinematics and compliance, steering dynamics, advanced active suspension technologies; and tire force and moment mechanics.

The 9 technical papers in this collection focus on innovations on rotors, calipers and overall brake system technologies, and also on their integration to the vehicle. The scope of coverage includes performance enhancements, drag reduction, weight reductions and thermal management by new designs and innovative materials.

This technical paper collection is focused on vehicle dynamics and controls using modeling and simulation, and experimental analysis of passenger cars, heavy trucks, and wheeled military vehicles. The papers address active and passive safety systems to mitigate rollover, yaw instability and braking issues; driving simulators and hardware-in-the-loop systems; suspension kinematics and compliance, steering dynamics, advanced active suspension technologies; and tire force and moment mechanics.

Topics of this technical paper collection include (but are not limited to) nonlinear behavior of tires and wheels, static/dynamic stress analysis, nonlinear material modeling, contact stress, impact, noise, vibration, traction, hydroplaning, effect of tires on vehicle performance, rolling resistance, and durability.

Abstract The flow around and downstream of the front wheels of passenger cars is highly complex and characterized by flow structure interactions between the external flow, fluid exiting through the wheelhouse, flow from the engine bay and the underbody. In the present paper the near wall flow downstream of the front wheel house is analyzed, combining two traditional methods. A tuft visualization method is used to obtain the limiting streamline pattern and information about the near wall flow direction. Additionally, time resolved surface pressure measurements are used to study the pressure distribution and the standard deviation. The propagation of the occurring flow structures is investigated by cross correlations of the pressure signal and a spectral analysis provides the characteristic frequencies of the investigated flow.