• Journal of Institute of Control, Robotics and Systems
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• v.10 no.7
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• pp.634-642
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• 2004

Unlike actual vehicles, a vehicle driving simulator is limited in kinematic workspace and bounded on dynamic characteristics. So it is difficult to simulate dynamic motions of a multi-body vehicle model. In order to overcome these problems, a washout algorithm which controls the workspace of the simulator within the kinematic limitation is needed. However, a classical washout algorithm contains several problems such as generation of wrong sensation of motions by filters in tilt coordination, requirement of trial and error method in selecting the proper cut-off frequencies, difficulty in returning the simulator to its origin using only high pass filters and etc. This paper proposes a new tilt coordination method as an algorithm which gives more accurate sensations to drivers. In order to reduce time for returning the simulator to its origin, a new washout algorithm that the proposed algorithm selectively onset mode from high pass filters and return mode from error functions is proposed. As a result of this study, the results of the proposed algorithm are compared with the results of classical washout algorithm through the human perception models. Also, the performance of the suggested algorithm is evaluated by using human perception and sensibility of some drivers through experiments.

• Journal of Mechanical Science and Technology
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• v.19 no.spc1
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• pp.272-282
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• 2005

A vehicle driving simulator is a virtual reality device which makes a man feel as if he drove an actual vehicle. Unlike actual vehicles, the simulator has limited kinematical workspace and bounded dynamic characteristics. So it is difficult to simulate dynamic motions of a multi-body vehicle model. In order to overcome these problems, a washout algorithm which controls the workspace of the simulator within the kinematical limitation is needed. However, a classical washout algorithm contains several problems such as generation of wrong sensation of motions by filters in tilt coordination, requirement of trial and error method in selecting the proper cut-off frequencies and difficulty in returning the simulator to its origin using only high pass filters. This paper proposes a washout algorithm with new tilt coordination method which gives more accurate sensations to drivers. To reduce the time in returning the simulator to its origin, an algorithm that applies selectively onset mode from high pass filters and return mode from error functions is proposed. As a result of this study, the results of the proposed algorithm are compared with the results of classical washout algorithm through the human perception models. Also, the performance of the suggested algorithm is evaluated by using human perception and sensibility of some drivers through experiments.

• Journal of Institute of Control, Robotics and Systems
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• v.10 no.6
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• pp.519-528
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• 2004

For reappearance of driving perception in a driving simulator, a washout algorithm is required. This algorithm can reappear the vehicle driving motions within workspace of the driving simulator. However classical washout algorithm contains several problems such as selection of order, cut-off frequency of filters, generation of wrong motion cues by characteristics of filters, etc. In order to overcome these problems, this paper proposes a new washout algorithm which gives more accurate sensations to drivers. The algorithm consists of an artificial inclination of the motion plate and human perception model with band pass filter and dead zone. As a result of this study, the motion of a real car could be reappeared satisfactorily in the driving simulator and the workspace of motion plate is restrained without scaling factor.

• Journal of Institute of Control, Robotics and Systems
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• v.15 no.8
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• pp.823-830
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• 2009

For developing automotive parts and telematics devices the real car test often shows limitation because it needs high cost, much time and has the possibility of the accident. Therefore, a Vehicle Driving Simulator (VDS) instead of the real-car test has been used by some automotive manufactures, research centers, and universities. The VDS is a virtual reality device which makes a human being feel as if one drives a vehicle actually. Unlike actual vehicle, the simulator has limited kinematic workspace and bounded dynamic characteristics. So it is difficult to simulate dynamic motions of a multi-body vehicle model fully. In order to overcome these problems, a washout algorithm which restricts workspace of the simulator within the kinematic limits is needed, and analysis of dynamic characteristics is required also. However, a classical washout algorithm contains several problems such as time delay and generation of wrong motion signal caused by characteristics of filters. Specially, the classical washout algorithm has the simulator sickness when driver hardly turns brakes and accelerates the VDS. In this paper, a new washout algorithm is developed to enhance the motion sensitivity and improve the simulator sickness by using the vehicle tilt signal which is generated in the real time vehicle dynamic model.

• Journal of Mechanical Science and Technology
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• v.17 no.2
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• pp.221-229
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• 2003

In the virtual environment, reality can be enhanced by offering the motion based on a motion simulator in harmony with visual and auditory modalities. In this research the Stewart-Gough-platform-based motion simulator has been developed. Implementation of vehicle dynamics is necessary in the motion simulator for realistic sense of motion, so bicycle dynamics is adopted in this research. In order to compensate for the limited range of the motion simulator compared with the real vehicle motion, washout algorithm composed of high-pass filter, low-pass filter and tilt coordination is usually employed. Generally, the washout algorithm is used with fixed parameters. In this research a new approach is proposed to tune the filter parameters based on fuzzy logic in real-time. The cutoff frequencies of the filters are adjusted according to the workspace margins and driving conditions. It is shown that the washout filter with the fuzzy-based parameters presents better performance than that with the fixed ones.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.5 s.98
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• pp.19-28
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• 1999

In this study, a real-time simulation system and a washout algorithm for an excavator have been developed for a driving simulator with six degrees of freedom. The excavator model consisting of a boom. bucket, upper frame, lower frame and four wheels, has total 11 degrees of freedom. The suggested washout algorithm consists of high and low pass filters with second order. The high pass filters cut off low frequency of the motion cues limited by platform motion. The cut off frequency for the tilt coordination are suggested for a realistic regeneration of excavator motion.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.496-499
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• 1997

This paper describes the operating software of a motion system developed for a driving simulator, consisting of a six degree of freedom Stewart platform driven hydraulically. The drive logic, consisting of an washout algorithm, inverse kinematic analysis, and a control algorithm, has been developed and applied for creating high fidelity motion cues. The basic environment of the operating software is based on LabVIEW 4.0 and DLL modules compiled by Fortran.

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.101.1-101
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• 2002

Vehicle driving simulator is a virtual reality device which makes a human being feel as if the one drives a vehicle actually. Unlike actual vehicle, the simulator has limited kinematic workspace and bounded dynamic characteristics. So it is difficult to simulate dynamic motions of a multi-body vehicle model fully. In order to overcome these problems, washout algorithm which restricts workspace of the simulator within the kinematic limits is needed, and analysis of dynamic characteristics is required also. However, it is difficult to select the proper cutoff frequency of filters in washout algorithm. This paper introduces the signal compression method as an effective method to analyze the sim...

• Proceedings of the KSME Conference
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• 2001.11a
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• pp.654-659
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• 2001

In the virtual environment, reality can be enhanced by offering the motion based on a motion simulator in harmony with visual and auditory modalities. In this research, the Stewart platform based motion simulator has been developed. This motion simulator is driven by the electric motors, and offers the slightly wider workspace compared to the commercial available simulators. In order to compensate for the limited range of the motion platform, the washout filters with fixed coefficients have been usually adopted. In this paper the new approach is proposed to tune the filter coefficients based on the fuzzy logic on the real-time basis. It is shown that performance with the variable filter coefficients is better than that with the fixed ones. The driving simulator based on the bicycle dynamics was developed by integrating the motion simulator and graphic system.

• Proceedings of the Korea Society for Simulation Conference
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• 2002.05a
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• pp.109-114
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• 2002

현재 게임시장에서는 사용자가 직접 게임을 체험하는 체감형 게임기가 활발히 개발되고 있다. 대다수의 제품들은 운동을 재현하기 위하여 6개의 축으로 이루어진 Stewart 형의 모션 플랫폼을 사용하고 있다. 본 연구개발에서 시도되고 있는 게임기는 모션이 가미된 콘솔형 아케이드 시뮬레이션 게임기에 해당되는데, 인간의 감성인자중 운동감성에 바탕을 둔 운동 재현을 고려하여 워시아웃(Washout) 알고리즘을 적용하였고, 일반적으로 6개의 축으로 구현하는 운동 자유도를 짐발(Gimbal)형으로 재현하고자 하였다. 또한 실시간 스케줄러와 H/W 입출력 및 통신 드라이버에 대한 개발을 수행하였으며, 게임용 실시간 시뮬레이션에 적합한 정확도와 실시간성을 유지하도록 롤러코스터 상에서 이루어지는 차량운동이 모델링 되었다. 특히, 연구사례를 찾기 어려운 짐발형 운동판에 대한 워시아웃 필터를 시뮬레이터 탑승자의 감성공학적 특성을 반영할 수 있도록 설계하였다.