IISc Research Summary:

  • Developed a 1D FE model of shape memory alloy (SMA) wire actuator. Studied the effect of microstructure inhomogeneity and boundary conditions on the hysteretic behavior during mechanical and thermo-electric loading.
  • Designed and fabricated a work-bench for testing, training and investigating fatigue degradation of SMA wires under mechanical and thermal loading.
  • Worked on the design and developed a SMA wire integrated aerofoil with morphing capability.
  • Worked on the design and development of SMA wire integrated adaptive composite structure. Studied the effect of loading rate and performance degradation.

Virtual Four-Post Test for Automotive Ride Analysis (Undergraduate Final Project)

Due to the rise in standard of living over the past few decades, the demand for cars has tremendously swelled up. As a result of which, the automakers are under intense pressure to design and develop vehicles at a faster rate. The vehicle designers encounter problems in three stages of design and development namely component, subsystem and vehicle level. The vehicle level problems are regarded as most important due to the fact that customers’ perception of quality is based on vehicle level performance. The traditional vehicle development process is not competent enough to meet the rising demand. This is due to the reliance on proving ground testing using hardware prototypes to tackle the vehicle level problems. To meet this rise in demand, the automakers are adopting the modern approach of “virtual product  development”, where the designers build, test and optimise virtual prototypes before actually fabricating the vehicle.

Ride comfort is one of the major vehicle issues which consume a significant amount of vehicle development time. The focus of this project is to evaluate the ride comfort of a vehicle using a virtual “Four-Post-Test-Rig”. A “Four-Post-Test-Rig” consists of four servo hydraulic actuators which are coordinated to simulate the movement of the vehicle over a terrain.

In this project, a virtual “Four-Post-Test-Rig” and a detailed vehicle model to represent the actual car is modeled using a software namely MSC ADAMS. Road inputs to this test rig are generated using MATLAB software according to standard ISO 8608, (Mechanical vibration – Road surface Profiles – Reporting of measured data). The advantage of use of a “Four Post Test Rig” is its versatility. Other than evaluating ride comfort, it may also be used to aid suspension component design, i.e. durability estimation of vehicle components. Therefore, the “Four-Post-Test-Rig”, is used for measuring the suspension load distribution, which is used in the finite element analysis of wheel knuckle.

Four-Post Simulation

The outcome of this project is that, a better vehicle design, in terms of ride comfort and component durability, would be produced at an expense of reduced cost and development time. The human body is perceptible to a specific range of frequencies which decides the comfort/discomfort aspect of the ride. With the help of a virtual “Four Post Test Rig”, the frequencies of vibration at various locations may be evaluated and the suspension may be optimised to satisfy the comfort requirements. The measurement of component loads ahead of time, would aid the designer to effectively design the component with reduced cost and testing. This would ultimately produce a vehicle with higher durability and comfort levels.

Automotive Handling Analysis and Design Studies (Undergraduate Hobby Project)

The automotive industry is one of the most competitive sectors in today’s world. The auto manufacturers are under intense pressure to develop and deliver innovative vehicles early to the market at reduced expenses. Customers’ perception of quality is based on the vehicle level performance. Factors like ride comfort, handling and Noise-Vibration-Harshness (NVH) form the basis for customers’ perception and are of strategic importance as brand value. Since these aspects are governed by the design of suspension system, the automakers are constantly trying to improve and alter the existing design.

Conventional approach to suspension design and evaluation involves the use of hardware prototypes for testing. The drawbacks of this approach like prolonged product development and skyrocketing costs have forced the automakers to radically alter their design process. This has lead to the use of virtual prototyping i.e. Computer Aided Design (CAD) in the product development. The virtual analysis of the operating scenarios early in the design process paves way for the creation of an optimum suspension design with reduced cost and time.

This project focuses on the handling analysis of a vehicle and evaluation of the empirical relationship between the critical suspension design parameters and the vehicle performance characteristics through design studies. This involves creation of a “Digital Mock Up” (DMU) of the actual vehicle using MSC ADAMS. The handling analysis is carried out as per the procedures outlined by ISO 4138 (Steady State Cornering – Constant Radius Test) and ISO 3888 (Moose Avoidance Test or Double Lane Change Manoeuvre). Finally design studies are carried out to evaluate the relation between the suspension design parameters and the vehicle performance characteristics.

The virtual analysis of the suspension system early in the design process not only reduces the product development time and expenses but also leads to a better design in terms of its performance. This results in an improved overall performance of the vehicle.

Moose Avoidance Test (ISO 3888)

Moose Avoidance Test (ISO 3888)

Steady State Cornering (ISO 4138)

Steady State Cornering (ISO 4138)