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This paper presents a methodology of trajectory planning for the surrounding-aware lane change maneuver of autonomous vehicles based on a data-driven method. The lateral motion is planned by sampling candidate patterns which are defined based on quintic polynomial functions over time. Based on the cost evaluation among the sampled candidates, the optimal lateral motion pattern is selected as a reference and tracked by the controller. The longitudinal motion is planned and controlled using Model Predictive Control (MPC) which is an optimal control method designed considering the surrounding traffic information. To realize the lane change motion similar to the human driving behavior in the surrounding traffic situation, the human driving pattern is modeled in the form of motion parameters and considered in planning the lateral and longitudinal motion.

This paper describes a failsafe system of automated driving vehicles. The failsafe system consists of the following two parts: sliding mode observer-based environment sensor, chassis sensor fault detection, and emergency deceleration control. Two sliding mode observers are designed to reconstruct the fault of acceleration and environment sensor(Lidar) in a longitudinal direction. In the environment sensor's fault detection part, the longitudinal vehicle model receives clearance and relative velocity values. Therefore, failure diagnosis is possible regardless of environmental sensors, such as radar, lidar, and camera. This paper's sensor data is the failure of Delphi's Electronically Scanning Radar (ESR) and Ibeo's LUX Lidar installed in an autonomous vehicle. The emergency deceleration control algorithm employs the sliding mode control with adaptive convergence time. In the event of a failure, it is significant to control the vehicle within a short period safely.

This paper describes a lateral control of autonomous large size buses on road with large curvature. In the case of long and wide commercial vehicle such as large bus, applying centerline tracking controllers in constrained environments such as large curved road (e.g. turning at intersection) may cause some concerns. Two concerns are considered: inner lane crossing related to collisions with curb and opposite lane crossing related to threatening surrounding vehicles. Considering relations between width and curvature of the road and length and width of the large size bus, the curvature of road at which inner or outer lane crossing begin to occur was calculated when centerline tracking controller was applied. Thus, the proposed algorithm optimizes motion of the bus by using model predictive control (MPC) using road geometry as constraints.

The flame propagation characteristic is one of the greatest factor that determines the performance of spark ignition (SI) engines. The in-cylinder flow dynamics is very significant in terms of flame propagation because of its direct influence on the flame shape, turbulent flame speed, and the ignition quality. A number of different techniques are available to optimize the in-cylinder flow and maximize the utilization of turbulence for faster combustion, and tumble enhancement by intake port geometry is one of them. It requires excessive computational expenses to evaluate multiple designs under wide range of operating conditions by 3D-CFD, therefore, a low-dimensional model would be more competitive in such design optimization process. This work suggests a new modification approach for typical 0D turbulence model to take account for the tumble generation during the intake process as well as the turbulence characteristics associated with it.

Validation of a vehicle simulation model of the Chevrolet Volt 2016 was conducted. The Chevrolet Volt 2016 is equipped with the new “Voltec” extended-range propulsion system introduced into the market in 2016. The second generation Volt powertrain system operates in five modes, including two electric vehicle modes and three extended-range modes. Model development and validation were conducted using the test data performed on the chassis dynamometer set in a thermal chamber of Argonne National Laboratory’s Advanced Powertrain Research Facility. First, the components of the vehicle, such as the engine, motor, battery, wheels, and chassis, were modeled, including thermal aspects based on the test data. For example, engine efficiency changes dependent on the coolant temperature, or chassis heating or air-conditioning operations according to the ambient and cabin temperature, were applied.

Exterior shape of automobile can be represented by shape function through this study so that aerodynamic shape parameters can be easily controlled and changed. Also ordinary geometric information can be extracted easily from shape function model by simple calculations. It is possible to predict the aerodynamic performance of functional virtual car models which are transformed continually by developing automated program in initial design stage that includes all of above process. Innovative vehicle design process with exterior design guide will be proposed for stylist, engineer and packaging department in order to achieve low aerodynamic drag and high fuel efficiency targets.

This paper presents a Unified Chassis Control (UCC) strategy to improve vehicle stability and maneuverability by integrating Electronic Stability Control (ESC) and Active Front Steering (AFS). The UCC architecture consists of two parts: an estimator and a controller. The estimator is designed to estimate longitudinal and lateral tire forces and the controller is designed in two stages, namely, an upper level controller and a lower level controller. The upper level controller, provides the desired yaw moment for vehicle lateral stability by adopting a sliding control method. The lower level controller, provides the integration method of the AFS and ESC strategies for the desired yaw moment and is designed by optimal tire force coordination.

This paper presents a longitudinal control algorithm for an adaptive cruise control (ACC) with collision avoidance (CA) in multiple vehicle traffic situations. The proposed algorithm consists of a multi-target tracking filter, a primary target selection algorithm and an integrated ACC/CA system. The multi-target tracking filter is used to smooth the sensor signal, and makes it possible to apply to a control system. The primary target selection algorithm decides an in-lane target and provides the information to an integrated ACC/CA system in order to drive a subject vehicle smoothly and improve safety in complex traffic situations. Finally, the integrated ACC/CA system computes the desired acceleration. The performance and safety benefits of the multi-vehicle ACC/CA system is investigated via simulations using real data on driving. Simulation results show that the response of multi-vehicle ACC/CA system is more smooth and safer at a change of traffic situations.

Two-mode hybrid architectures with three planetary gear sets and four clutches will bring both flexibility and complexity to energy management of powertrains. In order to take full advantage of the increased degrees of freedom, highly delicate operation strategies are needed. We develop transmission efficiency models for power-split modes, and present a mode shift strategy assuming no battery power. When battery load leveling is additionally considered, the respective optimal operation set for each mode can be obtained and compared to yield a mode shift algorithm for general hybrid operation situations. The investigation of the strategies shows how frequently each mode is used, and verifies the effectiveness of fixed gear operations. We check the validity of the strategies by applying the algorithm to dynamic optimization and by predicting how it works during an actual driving simulation.

As the number of user selectable electrical modules increases for passenger car, the number of cars with different combinations of option can easily exceed 100,000 cars. It results to a situation where we can not manually verify all the logical connection by making wiring combinations for each car. In this paper, we propose an algorithm that can reduce verification time for all possible wiring with available option combinations. The algorithm separates the whole wiring circuits into independent circuits and verifies the logical connections for each independent circuit with all possible options. The algorithm is time effective so the required time to verify the connections increases logarithmically as the number of possible car increases. The algorithm was implemented as software verification tool and its effectiveness was proved to be feasible.

This paper proposes a new screening attenuation evaluation method (PHSA) for hybrid power cables. Hybrid power cables connect battery, inverter and motor. As the noise and shield characteristics of these cables are different from general communication shield wires, new method for evaluating screening attenuation is needed. We considered the radiation direction, noise current path and various load terminations to evaluate the screening attenuation which is different from standard screening attenuation measurement. Feasibility and effectiveness of the proposed method were verified with real experiment results.

Due to increasing amount of modules and customized options in commercial vehicles, it becomes more and more difficult to verify the circuit design. In this paper, a wire segment error locating algorithm is proposed to automate the exact wire segment error locating process. When a wrong connection is found by existing tool, guided by the exact description of wire segment error, this algorithm can locate exact wire segment error in the connection by searching for the one that has at least one neighboring segment from a correct connection.

The achievement of improved NVH performance with light weighted body and low cost is very important, but difficult job to be accomplished in vehicle development. One of the various methods for the accomplishment of this goal is the optimization of the stiffness attached to a vehicle body and chassis. It is known that sufficient stiffness at the body attachments improves the flexibility of bushing rate tuning. In this paper, the theoretical consideration and analysis tool to estimate local stiffness value quantitatively are introduced. Also, the local stiffness values at various attachment locations in trimmed body are measured. The operational forces at body attachments are estimated through the TPA (Transfer Path Analysis). The suitability of attachment stiffness is judged based on the required NVH target to attain the optimal attachment stiffness in vehicle body.

This paper introduces a systematic wiring guideline which includes coupling noise calculation, wire layout design, and wire type selection methodologies. The coupling theory between wires has been introduced long time ago but it was not successfully applied to real automotive wiring design due to the complexity in the theory such as large number of parameters and many different conditions in automotive wiring environment. In this paper, the complexity is reduced by separating physical parameters and electrical parameters and identifying controllable parameters and given parameters. This paper first introduces parameters which are used in the coupling equations and automotive wiring design, then the coupling noise calculation method which uses the coupling equations is introduced. The systematic automotive wiring guideline which prevents noise problem in various design stage such as system filter design, wire layout design, wire type selection is introduced.

A module based IPS (Intelligent Power Switch) evaluation system is proposed in this paper. As the IPS is gradually replacing the conventional relay and fuses, the stability and reliability of power system depends more on these IPS. The proposed IPS evaluation system outperforms the conventional manual evaluation in terms of speed and efficiency. This paper will introduce the structure of hardware and software of the IPS evaluation system. The system is placed between the module and cable connector to evaluate the module in an operating car without changing the cables. The control and signal processing is carried out by personal computer which is connected to the evaluation system by USB (Universal Serial Bus). The load resistance can be switch from actual load to arbitrary value using relay circuitry and DC electric load controlled by GPIB (General Purpose Interface Bus). CAN (Controller Area Network) circuits were added to control the IPS mounted inside the module.

This paper describes the ground system model and algorithm for a ground level simulation tool. First, the modeling of an automotive ground system will be discussed and the algorithm for a simulation tool will be explained. We divided the model into a ground tree and a ground body. The ground tree model consists of resistance formed by the wires that connect the load to ground point with various structures and the ground body model consists of resistance between ground points in the car body. The wires with large current, such as engine ground cable, was modeled in detail by dividing the resistance into wire, bolt, and clamping resistance, in order to simulate the effect of increased contact resistance after durability test. The algorithm of the ground level simulation tool was designed to adjust the currents of the alternator, battery, and ground points in order to evaluate the various driving and load conditions.

As most of today's automatic transmissions adopt a electro-hydraulic control system, the role of electronically controlled solenoid valves occupies an important position. This paper presents a dynamic modelling technique of a proportional control solenoid valve(PCSV) for automatic transmissions in terms of the system identification theory, and analyzes the dynamic characteristics of the PCSV in frequency domain. Also we find that there are good matches between the nonlinear dynamic simulation results and the experimental data.