Your Selections

Joshi, Divyanshu
Show Only

Collections

File Formats

Content Types

Dates

Sectors

Topics

Authors

Publishers

Affiliations

Events

   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Development of a Graphical User Interface (GUI) Based Tool for Vehicle Dynamics Evaluation

Mahindra & Mahindra Ltd-Saravanan Muthiah
Mahindra & Mahindra, Ltd.-Divyanshu Joshi
  • Technical Paper
  • 2019-28-2397
To be published on 2019-11-21 by SAE International in United States
Title Development of a Graphical User Interface (GUI) Based Tool for Vehicle Dynamics Evaluation Authors Mr. Shubham Kedia, Dr. Divyanshu Joshi, Dr. Muthiah Saravanan Mahindra Research Valley, Mahindra & Mahindra, Chennai Objective Objective metrics for evaluation of major vehicle dynamics performance attributes i.e. ride, handling and steering are required to compare, validate and optimize dynamic behavior of vehicles. Some of these objective metrics are recommended and defined by ISO and SAE, which involve data processing, statistical analysis and complex mathematical operations on acquired data, through simulations or experimental testing. Due to the complexity of operations and volume of data, evaluation is often time consuming and tedious. Process automation using existing tools such as MS Excel, nCode, Siemens LMS, etc. includes several limitations and challenges, which make it cumbersome to implement. In the current work, a GUI based post-processing tool is developed for automated evaluation of ride, handling and steering performance. Methodology This work is about development of a centralized platform for quantification, visualization and comparison of ride, handling and steering performance metrics from testing and…
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Experimental Investigation on the Effect of Tire Pressure on Ride Dynamics of a Passenger Car

Mahindra & Mahindra Ltd.-Saravanan Muthiah
Mahindra Research Valley-Divyanshu Joshi
Published 2019-04-02 by SAE International in United States
Ride is essentially the outcome of coupled dynamics of various involved sub-systems which make it too complex to deal analytically. Tires, amongst these, are known to be highly nonlinear compliant systems. Selection of tires specifications such as rated tyre pressure, etc. are generally decided through subjective assessment. While experts agree that tyre pressure affects the attributes such as ride to a noticeable degree, the quantification of the change often remains missing. In the current work, vibration levels of various sub-systems relevant to ride in an SUV are measured for three different tyre pressures at different speeds over the three randomly generated roads. For the purpose, artificial road profiles of classes A, B and C are synthesized from the spectrum of road classes defined in ISO 8608:2016 and reproduced on a four-poster test rig. Various ride performance metrics such as weighted root mean square (RMS) acceleration, primary ride, secondary ride, frequency responses etc. are measured and compared across the tyre pressures (29, 32 and 35 PSI) on an SUV vehicle. Key findings include a trend of…
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

A Study on the Repeatability of Vehicle Ride Performance Measurements

Mahindra & Mahindra Ltd-Saravanan Muthiah
Mahindra Research Valley-Divyanshu Joshi, Shubham Kedia
Published 2019-01-09 by SAE International in United States
Across the automotive industries, objective measurements and subjective assessment of vehicle ride performance are routinely carried out during development as well as validation phase. Objective measurements are receiving increased attention as they are generally believed to offer a higher degree of objectivity and repeatability compared to the subjective assessment alone. Typical industry practices include the acquisition of vehicle-occupant vibrational response on specified road sections, test surfaces on proving grounds or in a controlled input environment such as four-poster test rig. In presented work, a study is performed on the repeatability of vehicle ride performance metrics such as weighted RMS acceleration and frequency responses using the data acquired in repeated trials conducted using three different sports utility vehicles (SUVs) on a sufficiently long designated road section. Intra-vehicle and inter-vehicle ride performances are compared and studied against the mentioned metrics. Results indicate a significant variability of results in repeated trials, which in few cases is found to exceed the variation across the vehicles. These variabilities can be arguably attributed to several inevitable practical constraints such as vehicle…
This content contains downloadable datasets
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

A Study on the Effect of Steering Input Frequency on Transient Lateral Dynamics of Four-Wheeled Passenger Vehicles

Mahindra & Mahindra Ltd-Saravanan Muthiah
Mahindra Research Valley-Divyanshu Joshi, Shubham Kedia
Published 2019-01-09 by SAE International in United States
Vehicle lateral dynamic response parameters such as yaw velocity, lateral acceleration, roll angle, etc. depend on the nature of steering input. Response parameters vary with the amplitude and frequency of steering input. This paper deals with developing insights into the effect of steering input frequency on transient handling dynamics. For the purpose two SUV segment vehicles with similar curb weight are considered. Vehicles are given pulse inputs of the amplitudes corresponding to 4 m/s2 steady state lateral acceleration and target speeds of 80 kmph and 100 kmph, as recommended in ISO 7401:2011. Steering inputs are executed using a Steering Robot (ABD SR30). Lateral transient dynamic response gains as well as natural frequencies of yaw are studied for 0-2 Hz input frequencies. Several insights are developed, adding to the understanding of transient lateral dynamics and its relationship with steering input.
This content contains downloadable datasets
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

A Study on Combined Effects of Road Roughness, Vehicle Velocity and Sitting Occupancies on Multi-Occupant Vehicle Ride Comfort Assessment

Indian Institute of Science-Divyanshu Joshi, Anindya Deb
Wayne State University-Clifford Chou
Published 2017-03-28 by SAE International in United States
It is recognized that there is a dearth of studies that provide a comprehensive understanding of vehicle-occupant system dynamics for various road conditions, sitting occupancies and vehicle velocities. In the current work, an in-house-developed 50 degree-of-freedom (DOF) multi-occupant vehicle model is employed to obtain the vehicle and occupant biodynamic responses for various cases of vehicle velocities and road roughness. The model is solved using MATLAB scripts and library functions. Random road profiles of Classes A, B, C and D are generated based on PSDs (Power Spectral Densities) of spatial and angular frequencies given in the manual ISO 8608. A study is then performed on vehicle and occupant dynamic responses for various combinations of sitting occupancies, velocities and road profiles. The results obtained underscore the need for considering sitting occupancies in addition to velocity and road profile for assessment of ride comfort for a vehicle.
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

A Study on Ride Comfort Assessment of Multiple Occupants using Lumped Parameter Analysis

Indian Institute of Science-Anindya Deb, Divyanshu Joshi
Published 2012-04-16 by SAE International in United States
Growing consumer expectations continue to fuel further advancements in vehicle ride comfort analysis including development of a comprehensive tool capable of aiding the understanding of ride comfort. To date, most of the work on biodynamic responses of human body in the context of ride comfort mainly concentrates on driver or a designated occupant and therefore leaves the scope for further work on ride comfort analysis covering a larger number of occupants with detailed modeling of their body segments. In the present study, governing equations of a 13-DOF (degrees-of-freedom) lumped parameter model (LPM) of a full car with seats (7-DOF without seats) and a 7-DOF occupant model, a linear version of an earlier non-linear occupant model, are presented. One or more occupant models can be coupled with the vehicle model resulting into a maximum of 48-DOF LPM for a car with five occupants. These multi-occupant models can be formulated in a modular manner and solved efficiently using MATLAB/SIMULINK for a given transient road input. The vehicle model and the occupant model are independently verified by favorably…
Annotation ability available