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    Pengaruh Sudut Camber Roda Depan Pada Kemampuan Belok Mobil Model 4 Dan 2 Roda Penggerak (4WD Dan RWD)

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    Some experts had conducted research on vehicles dynamics and stability through the various modeling and simulation. This paper proposes an experimental base research about influence of front wheel camber angle on cornering ability of 4 wheel vehicle. The experiment performed on four and two rear wheel drive of a remote control vehicle model car with variables front wheel camber angle and speed of vehicle. The result showed that negative front wheel camber angle impact could reduce the turning ability of vehicle. Four wheel drive car has better turning ability than two rear wheel drive car. The best turning ability of car accomplished if the front wheel camber angle is set at 00

    Wheels on Wheels on Wheels-Surprising Symmetry

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    While designing a computer laboratory exercise for my calculus students, I happened to sketch the curve defined by this vector equation: (x, y) = (cos(t), sin(t)) + 1/2(cos(7t), sin(7t)) + 1/3(sin(17t), cos(17t)). I was thinking of the curve traced by a particle on a wheel mounted on a wheel mounted on a wheel, each turning at a different rate. The first term represents the largest wheel, of radius 1, turning counter-clockwise at one radian per second. The second term represents a smaller wheel centered at the edge of the first, turning 7 times as fast. The third term is for the smallest wheel centered at the edge of the second, turning 17 times as fast as the first, clockwise and out of phase

    Dynamic analysis of ground steering response of aircraft with electric taxi system

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    To provide taxi capability without the use of engines or tractor, electric landing gear drive is considered as a potential system add-on. Driving torque and nose wheel steering angle controller are established which are verified by civil aircraft examples. Quasi-steady method is applied to calculate tire forces and moments. The ground steering response of aircraft is simulated, and then different taxi conditions including powered nose wheel mode and powered main wheel mode are compared. Two conclusions are obtained: Electric taxi system helps the aircraft turn on the spot and the turning radius is smaller than the aircraft using engines; differential powered main wheel mode has the minimum turning radius while turning-circle with uniform velocity, and it has smaller difference between two vertical loads of main landing gear than powered nose wheel mode

    Wheel Wear and Rail Damage Prediction for Wheels Turned with Thin Flanges

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    Economic Tyre Turning (ETT) is the process of turning wheels to a profile that has the same tread shape but a thinner flange than the design case, allowing less material to be removed from the wheel diameter. ETT can allow maintainers to extend wheel life, particularly when the wheel is approaching its minimum diameter. Modern wheel lathes are typically capable of turning such profiles but GB railway group standards do not currently permit their use. This paper investigates the effect of using ETT wheel profiles on the wheel-rail interface, in terms of wear and rolling contact fatigue (RCF) damage. It demonstrates how a Wheel Profile Damage Model (WPDM) can be used to accurately predict both the magnitude of wheel wear and the worn shape of the wheel for mileages exceeding 100,000 miles since turning. The paper presents results for one suburban and one inter-city train fleet. It discusses the validation of the wear prediction using data from the real fleets and the calibration methodology used to adjust the Archard wear model within the WPDM to improve the accuracy of the simulation results for specific routes. Having established that wear patterns can be predicted with a good degree of accuracy, the paper then examines how the predicted wear performance changes when wheel profiles with thin flanges (four different flange thicknesses at 1mm intervals from 28mm to 25mm) are used. The analysis is extended to predict the effect of using ETT on rail RCF for typical routes and operating conditions using a series of vehicle dynamic simulations. The analysis considers new 56E1 and 60E2 rails together with a selection of worn wheel and rail profiles

    Tribological approach to optimize traction coefficient during running-in period using surface texture

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    Risk of wheel-climb derailment increases if the traction coefficient in the wheel/rail contact is too high. This has been observed to happen more just after wheel turning. This novel work investigates how the traction coefficient rises during the running-in period, when textured surfaces are used to simulate a freshly turned wheel. Running-in curve of traction coefficient showed a momentary rise and a peak value of traction coefficient was observed to decrease with the increase in magnitude of the wheel surface texture. The change of the subsurface hardness and the microstructure were also dependent on the initial surface texture coincidentally and the work-hardening layer of the textured surface was thicker than that of smooth surface. A mechanism model of the effects of surface texture on traction characteristics during the running-in was presented. The work will allow recommendations of wheel turning to be made to help reduce the problem of wheel-climb derailment

    Cable steering system

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    Describes a steering system in an all-terrain four-wheeled vehicle with independent suspension where the necessary forces for steering control are supplied by cable and pulley actuators with the cable running parallel to the suspension arm between vehicle frame and wheel, steering control by the driver is by manipulation of right and/or left steering levers eliminating the need of steering wheel and steering column in front of the driver. The steering actuators are independent and there is no linkage for coordinating their turning angles. Close coordination of the wheel turning angles for achieving the turning angle relation between the wheels is by a non-linear linkage whereby the actuators are provided with separate displacement motions with the non-linear relation to achieve the desired relation between the steering angles of the wheels
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