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A methodology is presented to do accelerated vibration durability test, on Electro Dynamic Shaker (EDS) by using Power Spectral Density (PSD) profile based on typical customer usage pattern. A generalized iterative procedure is developed to optimize input excitation PSD profile on EDS for simulating the exact customer usage conditions. The procedure minimizes the error between the target channels measured on road and the response channels measured on EDS. Also, response of accelerometers and strain gauges at multiple locations on the test component are arrived at based on a single input excitation using this procedure. The same is verified experimentally as well. Different parameters like strain, acceleration, etc. are simulated simultaneously. This methodology has enabled successful simulation of road conditions in lab, thereby arriving at a correlation between rig and road. The correlation obtained is based on the simulation of the same failure mode as that of the road on the rig.

In India, scooters are now being increasingly used by young women because of its lesser weight and ease of riding. Prevalent riding conditions demand higher stability and manoeuvrability at low speeds, which could be achieved by an in-depth study. A virtual handling model of the scooter has been developed using multibody analysis software for studying the stability and manoeuvrability. Realising the role of tyre properties on the stability characteristics of two-wheelers, a new tyre model that can simulate combined slip conditions has been developed and used in the scooter model. A robust steering controller has been used for maintaining the desired path of the scooter. The virtual model has been analysed under linear and non-linear conditions for both straight running and cornering manoeuvres. The stability characteristics of the scooter have been studied by root locus and eigenvector analysis. The consistency of the model has been verified by a brief plausibility study.

Scooters are becoming increasingly popular in India. Competition in this segment has forced the product developers to put focus on development time reduction and quality improvement. Any physical failure of critical parts in the actual customer usage conditions can delay the product launch. The present study is about simulation of failure of crankcase during field trials. This involved creation of Finite Element model, evolution of proper loading and boundary conditions which capture the failure area, development of a static and an accelerated dynamic test in laboratory to reproduce the field failure, the optimization of the crankcase design through FEM to achieve acceptable stress values at critical areas and validation of these results through newly developed laboratory tests. Simultaneously, field trials, which initially produced this failure were conducted and no failures were observed. Thus, the current study has saved time of actual field trials (3∼4 weeks) after the redesign.

Vision based systems using cameras are widely used in various industry verticals. The basic functionality of a vision system is to detect an object and then recognize it. In current automotive industry these systems are being used in applications like collision avoidance, intelligent cruise control, blind spot detection, parking assistance, identify pedestrians, etc. During driving conditions, 2 wheeler and 4 wheeler drivers are required to concentrate more on the road because of which they may tend to miss the traffic signs; more often during night times. The traffic signs can be one way, U-turn, right/left turn prohibited, bump ahead and etc. So there is a need for a system which detects, recognizes and intimates these signs to the driver. Extensive research is being carried out in the area of recognizing a traffic sign, but more focused research is done for a complex problem of detecting the sign in the real world environment.

Two wheelers are very popular as means of transportation in ASIA. It is also used as load carrier in some places. Chassis frame is a very critical part of a two wheeler taking most of the loads coming from the roads. During the design and development stage, structural integrity of the frame needs to be established. Bump test is one of the critical life tests performed on the vehicle for evaluating the fatigue life of the frame. Normally, three to four iterations take place before frame passes this bump test. This is a time taking test process (1week per iteration) and does not guarantee the end result. In the new approach, the bump test simulation is made using ADAMS software. The ADAMS model is validated by using the axle accelerations measured in the physical bump test. Subsequently, the loads obtained from ADAMS model are used in FEM software and the stresses are predicted. The stress pattern helped in identifying the critical areas.

Fatigue life prediction is the most promising technique for drastic reduction of durability evaluation time, which is a critical element in the product development cycle. By using this technique, it is possible to reduce development time and cost, identify failure modes early in the development cycle, and design the component for optimum life. This paper discusses the optimisation of an important two-wheeler component namely, the center stand, using fatigue life prediction techniques. Also, it aims at establishing correlation among various customer usage patterns, accelerated endurance tests, and fatigue life prediction results using both experimental data and finite element (FE) models.

Tyres are the primary contact between the vehicle and the road. It serves as the medium of communication between the road and the rider, which it does in terms of road loads and displacements. Therefore, measurement of dynamic wheel forces experienced by a two-wheeler is crucial for tuning the ride and handling characteristics of the vehicle. Currently, there are standard wheel force transducers available in the market, which are extensively used in cars. However, mass of such a system is relatively high to be used on two-wheelers. Special wheels and adaptors increase the unsprung mass considerably, which changes the dynamics of the vehicle. Moreover, cost of such systems is exorbitantly high to be used for two-wheelers. This paper describes the development of an innovative and a highly versatile and low-cost alternative method for real-time measurement of dynamic wheel loads and moments of a two-wheeler when compared with the currently available systems in the market.

A methodology is presented to obtain loads coming on the handle bar of a motorcycle of one model and calculating generic loads from the same for all other motorcycle models. The handle bar of a motorcycle of model M1 was instrumented with strain gages and calibrated for vertical and horizontal loads. The instrumented handle bar was assembled on the vehicle and data was collected on the test rig in laboratory. The vertical and horizontal loads acting on the handle bar, on test rig was obtained based on the calibration performed. The loads thus obtained are for a particular motorcycle model M1 and is dependent on the wheel loads of that motorcycle. These loads were converted into generic load cases, which are applicable for all models of motorcycles. The generalized loads thus generated were used in predicting the fatigue life of handle bar of a different motorcycle model (M2) using FE analysis and MSC fatigue.

This paper aims at the estimation of dynamic wheel loads of a two-wheeler through mathematical modeling that will aid during the initial stages of product development. A half car model that represents a two-wheeler was used for this purpose. Road displacements were given as input to the model and the wheel loads estimated. Actual road data obtained from two-poster rig was used as input to the model thereby making it possible to calculate the wheel loads for different customer usage conditions on different roads. In this paper, a severe rough road was chosen for verification of the model with that of the rig as the rider dynamics on such roads are the most difficult to simulate even on the rigs. The estimated values from model were verified with those measured using a two-poster rig for the same road displacement. Attempt has been further made to establish a correlation between the ride comfort predictions from the model and the two-poster rig.

In recent times gearless scooters are becoming popular means of transport in ASIA because of their ease of handling in crowded traffic and superior comfort over motorcycles. Major difference, which is contributing for least vibrations incase of scooters is mechanism of engine mounting on the frame. In most of the cases motorcycle engines are rigidly fixed to the frame where as in case of scooters engine will be swinging with respect to frame. It is easy to design muffler mounting for fixed engines. Since there is no relative motion between engine and frame for motorcycle both can be fixed to frame. Swinging scooter engine demands muffler mounting directly on engine. These direct mounts may include bosses, brackets, and bolts. While useful for their intended purpose, it is possible that vibrational energy can pass between the exhaust components and the engine through this direct mounting.

Automobiles are incorporated with advanced technologies to improve riding experience, safety, and vehicle management. Considering riding experience, major concern prevails in starting and charging system. For quick start and stop, implemented Integrated Starter Generator (ISG) in two wheelers. The ISG system consists of an ISG machine and ISG controller. ISG machine acts as motor during cranking and generator during charging, controlled by ISG controller. Automation kit is made with the help of real sensors, actuators, and microcontroller to monitor and log the performance characteristics of ISG system during te sting in rig level. Sensors continuously monitor the performance parameters and once the parameters are not meeting the specification, actuators stop the testing and raise the indication. All tested data are stored in cloud and taken for analysis. This automation kit served two purposes. One is eliminated test running on the failure sample for full long testing duration.