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Today’s automotive industry is a highly competitive market where continuous innovation in design and production of vehicles is required to gain market share and survive in the market. This led to reduction in the life cycle of the design process and design tools. Identifying, understanding and refining these details is significant to develop sustainable cars. Body and chassis stiffness are important specifications of a passenger car which affects handling, steering and ride characteristics of the vehicle. It has been proved that torsional, lateral and local chassis stiffness can play a role in giving the customer a premium feeling by affecting key metrics in the vehicle dynamics behaviour of a passenger car. In this paper, the effect of chassis stiffness on vehicle dynamics performance is studied using computer aided engineering (CAE). Different attributes of vehicle dynamics like vehicle handling, On-Center feel and vehicle ride are considered as performance characteristics.

In the automobile industry, the door closing effort spells out the engineering and quality of the vehicle. After the visual impact a vehicle has on the customer, the doors are most likely the very first part of the vehicle he/she encounters, to enter and exit the vehicle. One of the customer’s very first impressions about the quality of the car is given by the behavior of the doors when opening and closing, the swinging velocity and the energy that is required to obtain a full latching that the door makes when closed by the user. Door closing effort gives an indication of how good or bad the vehicle is engineered. The purpose of this paper is to propose modifications in the door system which help in reduction of door closing effort or velocity by two different methods, EZ Slam Door and Bungee Rope. In this paper, parameters like hinge friction, hinge axis inclination, sealing, latch and air bind effect are analyzed which affect door closing effort.

Ride is an important attribute which must be accounted in the passenger segment vehicles. Excessive H point acceleration, Steering wheel acceleration, Pitch acceleration can reduce the comfort of the driver and the passengers during high frequency and low frequency rough road events. Excessive Understeer gradient, roll gradient, roll acceleration and Sprung mass lift could affect the Vehicle driver interaction during Steady state cornering, Braking and Step steer events. The concept architecture of the vehicle plays an important role in how comfort the vehicle will be. This paper discusses how to improve SUV ride performances by keeping handling performance attributes same or better than base vehicle. Multi Objective Optimization was carried out by keeping spring, bushing and damper characteristic as the design variables to avoid new system or component development time and cost.

Lateral Stability is an important attribute which must be accounted for in the pick-up truck segment vehicles. If designed in an improper way, undesirable effects such as oversteer or tail sway may occur. Excessive yaw rate magnitudes, or tail sway, can reduce the confidence of the driver during severe lane change events. The concept architecture of the vehicle plays an important role in how stable the vehicle will be. High yaw rate or tail sway during limit cornering was reported during prototype vehicle evaluations. The tested vehicle configuration incorporated a double wish bone front suspension with an antiroll bar and a rear solid axle suspension with leaf springs and an antiroll bar. The feedback was critically analysed using computer simulations of the condition found in on track testing. Since the vehicle was still with the validation team, quick solution was necessary. This paper discusses the process which resulted in improved vehicle performance.

A vehicle drifts due to several reasons from its intended straight path even in the case of no steering input. Vehicle pull is a condition where the driver must apply a constant correction torque to the steering wheel to maintain a straight-line course of the vehicle. This paper presents an investigation study into the characteristics of a vehicle experiencing steering drift. The aim of the work is to study vehicle stability and the causes of vehicle drift/pull during straight line to minimize vehicle pull level and hence optimize safety measures. A wobble in the steering wheel feels like the steering wheel is shaking to the left and right. This may get worse, if speed increases. This paper focuses on modelling and evaluating effects of suspension parameters, differential friction, brake drag variation, Unbalanced mass in the wheel assembly and C.G. location of the vehicle under multibody dynamic simulation environment.

A critical requirement for product design and development is meeting vehicle dynamic performance. Customers changing needs puts tremendous pressure on automotive businesses to launch new vehicles within short durations of time. This makes it mandatory to have a wide-ranging virtual simulation and vigorous validation process to provide best in class ride and handling performance of vehicles. Physical testing of prototypes is the most time-consuming activity, so there is a need of front loading to substitute these requirements at the initial stage of the development cycle. This paper summarizes the overall process for front loading vehicle dynamics requirements during basic architecture definition using virtual simulation. Basic dimensions, CG, weight distribution and steer angle of the new vehicle are derived using concept calculations based on benchmark vehicles. Vehicle dynamics trials are then done for the benchmark vehicles.

This method and its special process are particularly suited for the production of Porous free combustion chamber prototype aluminium cylinder head casting. Current methods for producing porous free combustion chamber are graphite coating and CI/Cu metal chill which are moderately effective in achieving porous free combustion chamber. However, these current methods have serious drawbacks like high rejections due to blow holes/gas porosity generated from graphite coating and fine porosity due to prolonged cooling because of slow rate of cooling while peak temperature of metal chills. The present work shows how this goal can be achieved in cylinder head casting of single cylinder high speed engine. Fundamental micro structural investigations are shown as well as the results of tensile tests, high temperature strength, corrosion behavior and static and dynamic component testing.