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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.

Two-wheelers especially scooters constitute a majority market share in Asian countries. A hybrid drive-train integration of electric motor/motors with a conventional IC engine is a suitable solution to achieve reduction in CO2 emissions and as an alternative to IC Engine only vehicles. A model based supervisory controller is proposed, considering the behavior of the electrical drive, IC engine as well as the transmission, which determines the modes of operation. The controller determines the commanded torque split between the engine and electric motor across all modes of operations. With the information about the driving cycle, an optimal controller based on dynamic programming that minimizes fuel and equivalent electrical energy consumption with charge sustaining feature is proposed. This supervisory controller was simulated for hybrid configuration running on WMTC driving cycle to minimize equivalent energy consumption.

Vehicle dynamic simulations demand tire models, which are computationally efficient and capable of reliably predicting the dynamics of the tire. Such simple steady state and transient reduced order models are also required by tire designers to make preliminary predictions concerning behavior and judge quantitatively the relative importance of each of the subcomponents. In the realm of three dimensional multi-body dynamics, most models used are semi-empirical, where the tire is characterized by a set of equations. While the highest hierarchy in the modeling regime is a full three dimensional finite element model, the ensuing deformable multi-body dynamics is not economical for simulation. In this paper we offer an exact methodology to extract tire physical properties in order to develop a reduced order model equivalent to a complete Finite Element tire.

Hybrid drive trains have to be cost effective for implementation in small two-wheelers especially scooters which constitute the majority of the market in several Asian countries. Integrating an electric motor with the conventional IC Engine drivetrain while retaining the CVT (Continuously Variable Transmission) is a cost-effective proposition. Such a development will need accounting for the behaviour of the engine, electrical drive and the belt driven CVT. A map-based engine model and a physics-based CVT model were developed in Simulink and validated with experimental data on the WMTC drive-cycle. A steady state map-based emission model and a motor model were also used. Simulations were performed on two parallel hybrid layouts namely P2 wherein the electric motor was placed before the CVT and P3 where the motor was placed in the final drive after the CVT while retaining the base 110 cc scooter powertrain.

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.

An Inertial Measurement Unit (IMU) provides vehicle acceleration that can be used in Active Vehicle Safety Systems (AVSSs). However, the signal output from an IMU is affected by changes in its position in the vehicle and alignment, which may lead to degradation in AVSS performance. Investigators have employed physics and data-based models for countering the impact of sensor misalignment, and the effects of gravity on acceleration measurements. While physics-based methods utilize parameters varying dynamically with vehicle motion, data-based methods require an extensive number of parameters making them computationally expensive. These factors make the above-explored methods practically challenging to implement on production vehicles. This study considers a 6-axis IMU and evaluates its impact on Antilock Braking System (ABS) performance by considering the IMU signal obtained with different mounting orientations, and positions on a Heavy Commercial Road Vehicle (HCRV).