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Numerical simulations offer a wide range of benefits. Therefore, they are widely used in research and development. One of the biggest benefits is the possibility of automated parameter variation. This allows testing different scenarios very quickly. Nevertheless, physical experiments in the laboratory or on a test rig are still, and will remain, necessary. Physical experiments offer benefits, e.g., for very complex and/or nonlinear systems and are required for the validation of numerical models. To enhance the quality of experimental NVH investigations and to make use of the benefits of numerical simulation during experimental investigations at the same time, numerical models can be integrated into physical test rigs using the mechanical hardware-in-the-loop (mHIL) method (also referred to as real-time dynamic substructuring, hybrid testing or active control of impedance).

The increasing interest in the application of Large Eddy Simulation (LES) to Internal Combustion Engines (hereafter ICEs) flows is motivated by its capability to capture spatial and temporal evolution of turbulent flow structures. Furthermore, LES is universally recognized as capable of simulating highly unsteady and random phenomena driving cycle-to-cycle variability (CCV) and cycle-resolved events such as knock and misfire. Several quality criteria were proposed in the recent past to estimate LES uncertainty: however, definitive conclusions on LES quality criteria for ICEs are still far to be found. This paper describes the application of LES quality criteria to the TCC-III single-cylinder optical engine from University of Michigan and GM Global R&D; the analyses are carried out under motored condition.

This paper presents an automated driving control algorithm for the control of an autonomous vehicle. In order to develop a highly automated driving control algorithm, one of the research issues is to determine a safe driving envelope with the consideration of probable risks. While human drivers maneuver the vehicle, they determine appropriate steering angle and acceleration based on the predictable trajectories of the surrounding vehicles. Therefore, not only current states of surrounding vehicles but also predictable behaviors of that should be considered in determining a safe driving envelope. Then, in order to guarantee safety to the possible change of traffic situation surrounding the subject vehicle during a finite time-horizon, the safe driving envelope over a finite prediction horizon is defined in consideration of probabilistic prediction of future positions of surrounding vehicles.

This paper presents the design and evaluation of an emergency driving support (EDS) algorithm. The control objective is to assist driver's collision avoidance maneuver to overcome a hazardous situation. To support driver, electrically controllable chassis components such as motor driven power steering (MDPS) and differential braking and surrounding sensor systems such as radar and camera are used. The EDS algorithm is designed for 3 parts: monitoring, decision, and control. The proposed EDS algorithm recognizes a collision danger using minimum lateral acceleration to avoid collision and time-to-collision (TTC) and driver's intention using sensor systems. The control mode is determined using the indices from monitoring process and the collision avoidance trajectory is derived with trapezoidal acceleration profile (TAP).

This paper describes a driving motor torque distribution strategy of six-wheel-driven electric vehicles for optimized energy consumption. In this research, this strategy minimizes motoring power consumption and maximizes regenerative braking power under given required power condition. The torque distribution controller consists of total required motor torque calculation part, upper and optimal torque calculation part, lower level controller. The upper level controller determines total required torque of vehicle. And the torque is determined by acceleration pedal input of driver and vehicle velocity. The lower level controller calculates energy consumption in given condition and distributes motor torque to driving motor minimizing energy consumption. In distributing optimal motor torque, it is important to get accurate characteristics of driving motor and performance constraint.

This paper is concerned with the torque distribution problem including slip limitation and actuator fault tolerance to improve vehicle lateral stability and maneuverability of six-wheeled skid-steered vehicles. The torque distribution algorithm to distribute wheel torque to each wheel of a skid-steered vehicle consists of an upper level control layer, a lower level control layer and an estimation layer. The upper level control layer is designed to obtain longitudinal net force and desired yaw moment, while the lower level control layer determines distributed driving and braking torques to six wheels. The algorithm takes vehicle speed, slip ratio and tire load information from the estimation layer, as well as actuator fault information from each in-wheel motor controller unit.

Emissions regulations are becoming more severe, and they remain a principal issue for vehicle manufacturers. Many engine subsystems and control technologies have been introduced to meet the demands of these regulations. For diesel engines, combustion control is one of the most effective approaches to reducing not only engine exhaust emissions but also cylinder-by-cylinder variation. However, the high cost of the pressure sensor and the complex engine head design for the extra equipment are stressful for the manufacturers. In this paper, a cylinder-pressure-based engine control logic is introduced for a multi-cylinder high speed direct injection (HSDI) diesel engine. The time for 50% of the mass fraction to burn (MFB50) and the IMEP are valuable for identifying combustion status. These two in-cylinder quantities are measured and applied to the engine control logic.

This paper describes a driving control algorithm based on a skid steering for a Robotic Vehicle with Articulated Suspension (RVAS). The RVAS is a kind of unmanned ground vehicle based on a skid steering using independent in-wheel drive at each wheel. The driving control algorithm consists of four parts: a speed controller for following a desired speed, a lateral motion controller that computes a yaw moment input to track a desired yaw rate or a desired trajectory according to the control mode, a longitudinal tire force distribution algorithm that determines an optimal desired longitudinal tire force and a wheel torque controller that determines a wheel torque command at each wheel in order to keep the slip ratio at each wheel below a limit value as well as to track the desired tire force. The longitudinal and vertical tire force estimators are required for the optimal tire force distribution and wheel slip control.

This paper describes the safety test simulation of electrical shock of FCV (Fuel Cell Vehicles) on human. Since FCV operates with high voltage, it is very dangerous to touch on or near the conductive parts. It may hurt human even when conductive parts are surrounded by protectors such as barriers or enclosures. Also various modes of a vehicle, such as driving, idle and failure, can affect electrical shock. It is difficult to carry out field experiments about electrical shock for FCV because of many combinations which depend on the operating voltages and the modes of a vehicle. And electrical safety of FCV must be verified before the manufacturing process. These are the main purposes of this study. MATLAB Simulink is the tool to conduct the simulation. All of the electronic devices in an FCV and a human body were modeled to measure current through human body when human touches on FCV. We performed the simulation with respect to driving, idle and failure mode.

In this paper, we investigate a method to calculate the dynamic instability of a disc brake system and propose a criterion of design modification. To estimate dynamic instability, complex eigenvalue analysis is performed for a brake system and the contribution factor of each component to an unstable complex mode is calculated using complex MAC(Modal Assurance Criteria). From the contribution factors, the most influential component is determined so as to decouple the complex mode, and its geometry is modified in view of the strain energy distribution. Evaluation through noise dynamometer tests verifies the reduction of squeal noises, and this is in accordance with the results of complex eigenvalue analysis.

This paper presents a real-time vehicle powertrain simulator and a pseudo real-time multi-vehicle platoon simulator. The developed powertrain simulator simulates the complex vehicle powertrain dynamics, including detailed shifting transients, in the PC environment in real time. The driver input is provided using a throttle pedal interfaced using the game port. The processor requirements vary depending on the simulation options selected. In the basic version, this requirement is only approximately 20% of a 300 MHz Pentium II- based PC. For multi-vehicle platoon simulation, a network configuration is proposed. It links several individual powertrain simulations via the TCP/IP network. This network platoon simulation is also linked to a server which graphically displays the multi-vehicle platoon operation. In this network configuration, due to a random delay in data transfer the simulation time kernel is made to lag real time.

Compliance elements such as bushings of a suspension system play a crucial role in determining the ride and handling characteristics of the vehicle. In this research, a general procedure for the optimum design of compliance elements to meet various design targets is proposed. Based on the assumption that the displacements of elastokinematic behavior of a suspension system under external forces are very small, linearized elastokinematic equations in terms of infinitesimal displacements and joint reaction forces are derived. Directly differentiating the linear elastokinematic equations with respect to design variables associated with bushing stiffness, sensitivity equations are obtained. The design process for determining the bushing stiffness using sensitivity analysis and optimization technique is demonstrated.

In order to reduce PM (Particulate Matter) emitted from diesel vehicles, we have been developing the particulate trap system using a burner since 1993. This AEFR system (Active Exhaust Feeding Regeneration System) shows considerably low peak temperatures and temperature gradients in the filter during the regeneration process. The AEFR system used the engine exhaust gas partially for the regeneration of the ceramic wall flow filter. It controlled the bypass flow rate of the engine exhaust gas actively for the combustion rate control of filtrated PM. The temperature distributions and temperature gradients in the filter during the regeneration process varied widely according to the regeneration control schemes. Scheme III has shown the most desirable peak temperatures and temperature gradients in the filter during the regeneration processes with AEFR system.