• Journal of the Korean Society for Precision Engineering
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• v.16 no.6
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• pp.90-99
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• 1999

A vehicle driving simulator is a virtual reality device which a human being feels as if the one drives a vehicle actually. The driving simulator is used effectively for studying interaction of a driver-vehicle and developing vehicle system of a new concept. The driving simulator consists of a vehicle motion bed system, motion controller, visual and audio system, vehicle dynamic analysis system, cockpit system, and etc. In it is paper, the main procedures to develop the driving simulator are classified by five parts. First, a motion bed system and a motion controller, which can track a reference trajectory, are developed. Secondly, a performance evaluation of the motion bed system for the driving simulator is carried out using LVDTs and accelerometers. Thirdly, a washout algorithm to realize a motion of an actual vehicle in the driving simulator is developed. The algorithm changes the motion space of a vehicle into the workspace of the driving simulator. Fourthly, a visual and audio system for feeling higher realization is developed. Finally, an integration system to communicate and monitor between sub systems is developed.

• Journal of the Korean Society of Marine Environment & Safety
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• v.19 no.6
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• pp.666-673
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• 2013

This paper proposes the performance evaluation test of attitude heading reference system (AHRS) suitable for small high speed autonomous underwater vehicle(AUV). Although IMU can provides the detail attitude information, it is sometime not suitable for small AUV with short operation time in view of price and the electrical power consumption. One of alternative for tactical grade IMU is the AHRS based micro-machined electro mechanical system(MEMS) which can overcome many problems that have inhibited the adoption of inertial system for small AUV such as cost and power consumption. A cost effective and small size AHRS which incorporates measurements from 3-axis MEMS gyroscopes, accelerometers, and 3-axis magnetometers has been developed to provide a complete attitude solution for AUV and the attitude calculation algorithm is derived based the coordinate transform equation and Kalman filter. The developed AHRS was validated through various performance tests as like the magnetometer calibration, operating experiments using land mobile vehicle and flight motion simulator (FMS). The test of magnetometer calibration shows the developed MEMS AHRS is robust to the external magent field change and the test with land vehicle proves the leveling error of developed MEMS AHRS is below $0.5^{\circ}/hr$. The results of FMS test shows the fact that AHRS provides the measurement with $0.5^{\circ}/hr$ error during 5 minutes operation time. These results of performance evaluation tests showed that the developed AHRS provides attitude information which error of roll and pitch are below $1^{\circ}$ and the error of yaw is below $5^{\circ}$ and satisfies the required specification. It is expected that developed AHRS can provide the precise attitude measurement under sea trial with real AUV.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.5
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• pp.621-626
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• 2019

The driver's steering wheel maneuver is a typical disturbance that causes excessive body motion and traveling instability of a vehicle. Abrupt and extreme operation can cause rollover depending on the geometric and dynamic characteristics, e.g., SUV vehicles. In this study, to cope with the performance limitation of conventional cars, fundamental research on the structurization of a control system was performed as follows. Mathematical modeling of the lateral behavior induced by driver input was carried out. A controller was designed to reduce the body motion based on this model. An algorithm was applied to secure robust control performance against modeling errors due to parameter uncertainty, $H_{\infty}$. Using the decoupled 1/4 car, a dynamic load simulating model considering the body moment was suggested. The simulation result showed the validity of the load-simulating model. The framework for a lateral behavior control system is proposed, including an experimental 1/4 vehicle unit, load simulating module, suspension control module, and hardware-in-the-loop simulation technology.

• Journal of the Korean Society for Railway
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• v.11 no.2
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• pp.176-181
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• 2008

This paper presents results from experimental analysis of a friction-driven wheel responsible for generating wheel squeal noise. Squeal noise generating mechanism has been examined under the laboratory condition by the model rig on a small scale. Creep characteristics and squeal noise were observed by changing the possible variables, such as relative velocities and friction coefficients in time- and frequency-domain.