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The aim of the present study is to develop feasible test methods to measure the lateral force characteristics of motorcycle tires. In this work, new experimental procedures are developed to estimate the lateral friction coefficient and lateral stiffness characteristics of motorcycle tires. A fairly accurate tire model is developed using the measured lateral force characteristics. Based on this tire model, the steer behavior and the cornering limits of the motorcycle are estimated using an analytical model of the vehicle. The results are validated with experimental data. The test methods proposed are shown to be adequate to estimate tire characteristics that are important for tire development and is less expensive compared to the standard testing facilities available.

The aim of the present study is to develop feasible test methods to measure tire parameters that can be used in two wheeler industry for tire development. In this work, test methods are developed to measure the longitudinal friction coefficient and stiffness characteristics of motorcycle tires. Using the measured longitudinal forces from the testing procedure, a fairly accurate tire model has been developed. Based on this tire model the braking performance of the motorcycle is estimated using an analytical model of the vehicle. These are validated with experimental data. It is found that there is a good match between the results. The test is conducted for various bias ply tires used in motorcycles and the results are presented. The test methods proposed are shown to be adequate to estimate tire characteristics that are important for tire development and is less expensive compared to the standard testing facilities available.

The diesel power train (engine and transmission) is the most significant mass contributor in a three- wheeled vehicle. High idling vibrations from the engine get transmitted to the structure and the body panels through the engine mounts. Isolation of these vibrations by proper design of rubber mounts is the most effective engineering approach to improve ride quality of vehicle. In the present study, a mathematical model of the powertrain and mount system is developed; with the engine and transmission being assumed to behave as a rigid body (6 degrees-of-freedom) and the compliance comes from the mounts. As a first step, the modes and natural frequencies are obtained. Following this the response to unbalanced inertial forces for an excitation frequency range of 20-60 Hz (1200-3600 rpm) has been obtained. The model is validated by comparing its results with results of previous published research work.

In recent years graphical dynamic system simulation has become very important in the design and development stage, as new strategies can be examined without expensive measurements. This paper describes the development of a real time simulation model for a turbocharged diesel engine and an automatic transmission of a tracked vehicle using graphical programming environment in Matlab/Simulink. This work is part of a vehicle simulation model which is under development. A Mean Value Engine Model (MVEM) is used for simulation of engine dynamics. A Torque Converter (TC) is used as a fluid coupling between the engine and the transmission gearbox. This model is used to predict the dynamic response, both in steady and transient operation. Various illustrative studies have been conducted to demonstrate the capability of the model to predict the transient system response.

The sources of gear rattle in automotive transmission and other components are clearance non-linearities, which include backlashes, multi-valued springs, hysteresis, etc. Periodic vibro-impacts are generated because of the single sided or double sided impacts. It is obviously desirable to develop an appropriate computer simulation model which can aid in the control of transient noise and vibration signatures. Such models can also be used to design experiments and to interpret measured data. Several approaches have been attempted in the past, but most common is the digital simulation of the governing differential equations describing the non-linear, torsional dynamics of the drivetrain. Some progress has been made in understanding the basic rattle phenomenon and in developing suitable mathematical models. This article intends to be a status report on the mathematical or computer models including pre- and post-processing considerations.