• Transactions of the Korean Society of Automotive Engineers
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• v.17 no.2
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• pp.57-66
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• 2009

In this paper, the steering characteristics of tracked vehicles are studied for the improvement of steering performance. The important design factor of military vehicles is high mobility. It is influenced by weight of a vehicle, engine capacity, power-train, and steering system. The military vehicle, which is equipped with caterpillar, has unique steering characteristics and is quite different from that of a wheeled vehicle. The steering of tracked vehicles is operated in the power pack due to different speeds of both sprockets. Under cornering conditions, power split and power regeneration are happened in the power pack. In case of power regeneration, power is transferred outside track after adding engine power and power inputted inside track from the ground. However, excessive power regeneration is transferred in the power pack. It damages mechanical elements. Therefore, it is necessary to analyze the steering system and check mentioned problem above. In this study, the detailed dynamic model of steering system is presented, which includes slippage between track and roadwheel, inertia force, and inertia moment. Finally, our model is compared with the Kitano model and we verified the validity of the model.

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.115.2-115
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• 2002

A real-time vehicle simulation system is a key element of a driving simulator because accurate prediction of vehicle motion with respect to driver input is required to generate realistic visual, motion, sound and proprioceptive cues. In order to predict vehicle motion caused by various driving actions of the driver on board the simulator, the vehicle model should consist of complete subsystems. On this paper, a tracked vehicle dynamic model with high efficiency and effectiveness is introduced that has been implemented on a training driving simulator. The multi-body vehicle model is based on recursive formulation and has been automatically generated from a symbolic computation package develop...

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.10
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• pp.1678-1683
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• 2001

The mobility of tracked vehicles is mainly influenced by the interaction between tracks and soil, so that the characteristics of their interactions are quite important fur the tracked vehicle study. In particular, the track tension is closely related to the maneuverability of tracked vehicles and the durability of tracks and suspension systems. In order to minimize the excessive load on the tracks and to prevent the peal-off of tracks from the road-wheels, the Dynamic Track Tensioning System (DTTS) which maintains the optimum track tension throughout the maneuver is required. It consists of track tension monitoring system, track tension controller and hydraulic system. In this paper, a dynamic track tensioning system is developed for tracked vehicles which are subject to various maneuvering tasks. The track tension is estimated based on the idler assembly model. Using the monitored track tension and con sidering the highly nonlinear hydraulic units, fuzzy logic controllers are designed in order to control the track tension. The track tensioning performance of the proposed DTTS is verified through the simulation of the Multi -body Dynamics tool.

• Journal of Applied Reliability
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• v.11 no.4
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• pp.331-342
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• 2011

The transmission of tracked vehicles performs complex functions as steering, shifting, braking, etc. and the system level life time has been a key influenced by the number of sub-parts like as gear assembly, torque converter, clutches, bearings and so on. In particular, the mechanical type steering system in tracked vehicle has impact shock torques in steering shift and those kind of shock torques can effect on the durability of many sub-parts in power train system. The field failure modes of gear assembly, steering assembly and the bearings of output shaft appear as a very complex phenomenon. In this study, the actual failure, which may occur in field, of the transmission was investigated comprehensively and that the endurance test on the resulting output shaft bearing failure analysis and life assessment was performed. Life time test method used in this study, developed for the purpose of the internal usage, and under these testing techniques the impact of the each bearing damage, which used in tracked vehicle transmission left / right outputs of different structures, was analyzed.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.473-476
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• 2005

Mobility of tracked vehicles is dependent on performance of its power equipment and suspension systems. Especially, its road wheels, components of its suspension systems, play an important role in distributing the vehicle weight on the ground and preventing from misguiding tracks. In this study, the maximum force acted on multipurpose tracked vehicles driven on the worst condition was calculated. And then FE analyses were carried out to evaluate the strength of the road wheels under the maximum force condition. For quality evaluation of the road wheels, FE simulations and experimental works were carried out under specific slant loads. Residual deformation for the slant loads was investigated and commented upon.

• Journal of the Korea Institute of Military Science and Technology
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• v.24 no.4
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• pp.457-466
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• 2021

This paper describes the design of model-based fault diagnosis software to apply to the propulsion system in tracked amphibious assault vehicle which consists of an engine, a transmission, a cooling system, and two waterjets. This software includes specific functions to detect the failures regarding sensor malfunctions, mechanical malfunctions, control errors, and communication errors. This software generates the proper malfunction codes which are classified as the warning and caution. In order to validate the fault diagnosis software, the manual and automatic test are performed using the test program with 32 test cases. Test results show that the designed fault diagnosis software is reliable and effective for applying to the propulsion system.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.17 no.3
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• pp.59-64
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• 2018

In general, tracked combat vehicles require excellent output performance of a power unit system to drive on special terrains and in extreme environmental conditions. However, high temperature and pressure are readily applied to the coolant hose in the power unit of the vehicles during high-speed driving under extreme road and weather conditions. These driving conditions can cause the separation phenomenon of the coolant hose in the power unit and consequentially engine overheating during driving. Therefore, a newly designed decompression device for the coolant hose has been proposed and manufactured to solve these problems in the present study. To validate of the newly proposed decompression device, the input and output pressures were measured under the before- and after-improvement conditions using experimental methods for different engine RPMs. In addition, the pre-heater temperature was measured under both conditions. From the experimental results, we expect that the current investigation can help to improve the driving performance of tracked combat vehicles.

• Journal of Ocean Engineering and Technology
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• v.27 no.2
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• pp.80-86
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• 2013

KIOST developed a deep-sea mining robot called "MineRo" to collect manganese nodules in 2007. MineRo operates on flat ground. SMS (seafloor massive sulfide) deposits are shaped like undulating mountains. This paper deals with a numerical analysis model of a mining robot for SMS deposits. The mining robot consists of a tracked vehicle, chassis structure with a turntable, boom arm with 2 articulations, excavation tool, discharging unit, hydro-electric system, and sensing-and-monitoring system. In order to compare and analyze the dynamic responses of the driving mechanism, various tracked vehicles are modeled using commercial software. Straight driving simulations are conducted under undulating ground conditions. A conceptual design of a mining robot with four track systems for SMS deposits is modeled on the basis of these results.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.8 no.2
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• pp.36-44
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• 2009

In this paper, we suggest a system of detecting a vehicle with lane violation, which can detect the vehicle with lane violation, by using the feature point tracking. The whole algorithm in the suggested system of detecting a vehicle with lane violation is composed of three stages such as feature extraction, register and tracking in feature for the tracking-targeted vehicle, and detecting a vehicle with lane violation. In the stage of feature extraction, the feature is extracted from the inputted image by sing the feature-extraction algorithm available for the real-time processing. The extracted features are again selected the racking-targeted feature. The registered feature is tracked by using NCC(normalized cross correlation). Finally, whether or not lane violation is finally detected by using information on the tracked features. As a result of experimenting the suggested system by using the acquired image in the section with a ban on intervention, the excellent performance was shown with 99.09% for positive recognition ratio and 0.9% for error ratio. The fast processing speed could be obtained in 34.48 frames per second available for real-time processing.

• Journal of Institute of Control, Robotics and Systems
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• v.15 no.4
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• pp.426-432
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• 2009

In this paper, redundancy resolution of UVMS (underwater vehicle-manipulate. system) is addressed. In general, UVMS has redundant DOFs (degrees of freedom) as many as DOFs of manipulator and these redundant DOFs can be used to optimize the configuration of UVMS while satisfying given tasks. We propose a performance index for redundancy resolution which minimizes the restoring moments of UVMS. The restoring moment can cause unintentional change of poses of UVMS. If the restoring moments remain small, control effort for keeping the poses of UVMS decreases. This means that energy consumption can be reduced by minimizing the restoring moments during conducting tasks. Proposed performance measure is optimized by gradient projection method. Generated trajectories by this redundancy resolution are tracked by robust PID controller. Numerical simulations are presented to demonstrate performance of the proposed algorithm.