Youn J.,Hyundai Kia Randnter |
Park I.,Hanyang University |
Sunwoo M.,Hanyang University
International Journal of Automotive Technology | Year: 2013
This paper presents a heuristic resource allocation and scheduling method, which is based on an integrated architecture that enables multiple missions to be embedded in a single electronic control unit (ECU) and a single mission to be distributed over multiple ECUs. The proposed design method is composed of resource(e.g. task and message) allocation, scheduling, and attribute assignments. From a given target application's task graph, the method generates a scheduling table specifying the release, start, and completion timings of tasks and messages. After that, all relevant attributes(e.g. priority of tasks and messages) are automatically assigned. In order to guarantee the functional and temporal requirements of target applications, design constraints such as the worst case response time, deadline, precedence relations, and physical limitations are concurrently considered. A chassis control system consisting of electronic stability control, an electro-mechanical brake, continuous damping control, and electronic air suspension is employed for evaluating the proposed method. The conventional chassis control system which is composed of seven ECUs was redesigned by only four ECUs without the degradation of control performance. Consequently, it is expected that the development time and production cost of distributed automotive control systems can be significantly reduced by the proposed design method. © 2013 The Korean Society of Automotive Engineers and Springer-Verlag Berlin Heidelberg.
Ko J.,Sungkyunkwan University |
Ko S.,Sungkyunkwan University |
Son H.,Sungkyunkwan University |
Yoo B.,Hyundai Kia Randnter |
And 2 more authors.
IEEE Transactions on Vehicular Technology | Year: 2015
In this paper, a brake system for an automatic transmission(AT)-based hybrid electric vehicle (HEV) is developed, and a regenerative braking cooperative control algorithm is proposed, with consideration of the characteristics of the brake system. The brake system does not require a pedal simulator or a fail-safe device, because a hydraulic brake is equipped on the rear wheels, and an electronic wedge brake (EWB) is equipped on the front wheels of the vehicle. Dynamic models of the HEV equipped with the brake system developed in this study are obtained, and a performance simulator is developed. Furthermore, a regenerative braking cooperative control algorithm, which can increase the regenerative braking energy recovery, is suggested by considering the characteristics of the proposed hydraulic brake system. A simulation and a vehicle test show that the brake system and the regenerative braking cooperative control algorithm satisfy the demanded braking force by performing cooperative control between regenerative braking and friction braking. The regenerative braking cooperative control algorithm can increase energy recovery of the regenerative braking by increasing the gradient of the demanded braking force against the pedal stroke. The gradient of the demanded braking force needs to be determined with consideration of the driver's braking characteristics, regenerative braking energy, and the driving comfort. © 2014 IEEE.
Lee D.,Hyundai Kia Randnter |
Perot F.,Exa Corporation |
Ih K.-D.,Hyundai Motor Company |
Freed D.,Exa Corporation
SAE Technical Papers | Year: 2011
Nowadays vehicle quality is rated for noise and vibration and the interior sound levels have become a major target of automotive companies. Strides have been made in reducing power train, tire and external wind noise over the years. However, HVAC and blower fan flow-induced noise reaches the interior cabin without any sound isolation and can strongly impact customer comfort. In the early stage of vehicle design, it is experimentally difficult to get an estimate of the flow pattern and sound levels. The goal of this study is to develop and validate a numerical noise prediction tool for complete HVAC systems noise, defined as the arrangement of sub-systems such as air intake duct, thermal mixing unit, blower, ducts and outlet vents. This tool can then be used during the development of vehicles to evaluate and optimize the aeroacoustics performances of the system without additional or belated experiments. The sound transmission through the dash or wall is not considered in this study and the focus is made on the primarily flow-induced noise contribution. The CFD/CAA numerical method use a time explicit, unsteady and compressible method based on the Lattice Boltzmann Method (LBM) during which flow and acoustics are calculated at the same time. The numerical method is used to estimate the noise from two productive HVAC systems mounted on a Simplified Vehicle Cabin (SVC) and real Production Vehicle Cabins (PVC). Results in term of flow and noise are compared and validated through experiments. The influence of the cabin structural modes and absorption on the broadband noise levels is also discussed. Copyright © 2011 SAE International.
Park S.,Hyundai Kia Randnter |
Taejin C.,DYMOS Co
SAE Technical Papers | Year: 2012
S.E.A.T (Seat Effective Amplitude Transmissibility) index is used to evaluate ride comfort under vehicle driving condition. The proposed objective evaluation methodology uses several accelerometers to derive an objective index which is more reasonable than subjective evaluation. Moreover, a CAE (Computer Aided Engineering) methodology is proposed to obtain simulation results using the measured acceleration data at seat mountings as input conditions to seat system assembly. Finally, several case studies are conducted for maximizing ride comfort using the CAE model. Copyright © 2012 SAE International.
Lee D.,Hyundai Kia Randnter
SAE Technical Papers | Year: 2012
For passenger car diesel engines, higher air density or higher boost pressure is essential to enhance power density and meet stringent emission regulations. However, single variable geometry turbines (VGT) are limited to eliminate the inherent drawbacks of turbochargers; low-end torque and rated power are hard to reconcile. With a serial two-stage turbocharger, outstanding power density-rated power of 165kW and low-end torque of 350Nm-was obtained from Hyundai Motor's R2.2l engine. Also, it was possible to maintain the maximum torque of 500Nm evenly from 1250rpm up to 2250rpm. Compared to the current R2.2l engine with a single VGT turbocharger, more than 12% of power density increased. The fuel economy of the two-stage turbocharged engine was slightly better than the current R2.2l engine, which resulted in further reduction of fuel consumption compared to a 3.0l single VGT engine. Vehicle test results also showed that the R2.2l engine with two-stage turbocharger could substitute the 3.0l single VGT engine without any deterioration of drivability. Copyright © 2012 SAE International.