• International Journal of Automotive Technology
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• v.7 no.5
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• pp.535-545
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• 2006

A nonlinear analysis of torsional self-excited vibration in the driveline system for wheeled towing tractors was presented, with a 2-DOF mathematical model. The vibration system was described as a second-order ordinary differential equation. An analytical approach was proposed to the solution of the second-order ODE. The mathematical neighborhood concept was used to construct the interior boundary and the exterior boundary. The ODE was proved to have a limit cycle by using $Poincar\'{e}-Bendixson$ Annulus Theorem when two inequalities were satisfied. Because the two inequalities are easily satisfied, the self-excited vibration is inevitable and even the initial slip rate is little. However, the amplitude will be almost zero when the third inequality is satisfied. Only in a few working modes of the towing tractor the third inequality is not satisfied. It is shown by experiments that the torsional self-excited vibration in the driveline of the vehicle is obvious.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1993.10a
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• pp.727-733
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• 1993

An attempt was made to mechanize the infield transportation system in a cocoa plantation. A small trailer was designed and fabricated and used with a commercial 2-wheeled walking tractor modified into a 4-wheeled tractor-trailer unit to suit the plantation conditions. The transporter had a capacity of 800 kg and could be loaded with about 1000 cocoa pods at a time and was well within the towing capability of a 10 hp tractor. Time and motion studies were conducted on a 30 acre, 6 year old cocoa plantation intercropped with coconut to compare manual and the tractor-trailer combination in relation to infield transportation. The total time taken to harvest 80 trees manually was computed to be 24 manuhours per hectare whilst the tractor-trailer combination required 18manhours.

• Journal of the Society of Naval Architects of Korea
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• v.60 no.4
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• pp.288-295
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• 2023

This paper deals with the dynamic simulation method for analysis of driving characteristics of aircraft and towing vehicles (TUG) on carrier vessel in wave motions. For prompt deployment in a short period of time, optimization of the movement of carrier aircraft becomes a major issue. In this regards, strategy studies using real-time simulation technology and optimal decision-making technologies are being conducted. In the present work, the dynamic characteristics of carrier aircraft and TUG connected by towbar or towbarless mechanism were investigated by means of multi-body dynamics model. Meanwhile, for real-time simulation, Dugoff's model of tire loads calculation was adopted. Through comparative analysis it was confirmed that the similarity of results between the multi-body contact model and the tire load calculation model can be achieved by coefficients tuning.