In some countries, there is very little standardization in the construction of speed-bumps (aka. speed-breakers), as a result of which the bottom of many cars scrape the speed-bumps. In this paper, we come up with a first order figure of merit that car manufacturers can use when adapting their cars to be sold in such countries, so as to minimize the chances of scraping the speed-bumps.
Table of Contents
1. Introduction
2. Model
2.1. Model Formulation
3. Results
4. Conclusion
Objectives and Research Themes
The primary objective of this paper is to develop a first-order figure of merit for car manufacturers and consumers to evaluate a vehicle's susceptibility to scraping when traversing non-standard speed-bumps, effectively modeling the interplay between ground clearance and wheel-base.
- Analysis of non-standard speed-bump profiles and their impact on vehicle undercarriages.
- Development of a mathematical model for ground-clearance and wheel-base requirements.
- Evaluation of the relationship between speed-bump length, vehicle wheel-base, and scraping risk.
- Empirical comparison of various automotive models using the derived figure of merit (FOM).
- Practical recommendations for manufacturers to optimize vehicle dimensions for safety.
Excerpt from the Book
2. Model
Non-standard speed-bumps come in varying profiles, as seen in Fig. 1. It is very difficult to model scrape-susceptibility for all the various profiles. Hence, as a first order model, we develop the model for a simple isosceles triangular profile shown in Fig. 1b.
Consider a vehicle negotiating such a speed-bump. It is clear that if the speed-bump is short enough (L < w), then the ground-clearance has to be greater than the speed-bump’s height (g > h). This is the trivial case. But most often, speed-bumps are longer and have a smoother up-ramp and down-ramp. Because of this, when the front wheels have crossed the peak of the speed-bump but before they completely cross the speed-bump, the rear wheels start climbing the up-ramp. This raises the height of the lowest point of the vehicle’s bottom, and hence reduces the chances of scraping the speed-bump. This is the reason why the ground-clearance requirements can be relaxed when the wheel-base is shorter than the speed-bump’s length. This is the non-trivial case, and this is what we model in the next section.
Summary of Chapters
1. Introduction: Outlines the problem of non-standard speed-bumps in developing countries and the subsequent risk of vehicle underbody damage due to lack of standard infrastructure.
2. Model: Presents a mathematical framework for analyzing the geometric interaction between vehicle dimensions and speed-bump profiles, specifically focusing on an isosceles triangular shape.
3. Results: Applies the developed model to compare real-world vehicle dimensions, demonstrating how the calculated figure of merit predicts scrape-susceptibility across different car models.
4. Conclusion: Summarizes the effectiveness of the analytical model for manufacturers and consumers in assessing vehicle safety regarding non-standard speed-bump navigation.
Keywords
Bottom, Car, Ground-clearance, Scrape, Speed-bump, Wheel-base, Vehicle dynamics, Scrape-susceptibility, Automotive design, Infrastructure standardization, Mathematical modeling, Non-standard profiles, Figure of merit.
Frequently Asked Questions
What is the core focus of this research?
The research addresses the lack of standardized speed-bump construction and the resulting safety concerns for vehicles that scrape their undercarriages on these bumps.
What are the primary parameters considered in the study?
The study primarily evaluates the interplay between a vehicle's ground-clearance and its wheel-base in relation to the length and height of a speed-bump.
What is the main objective of the proposed model?
The goal is to provide a "figure of merit" (FOM) that manufacturers and buyers can use to quantitatively evaluate a car's resistance to scraping on non-standard speed-bumps.
Which scientific methodology is employed in the paper?
The author uses geometric modeling and analytical derivations based on an isosceles triangular profile of speed-bumps to formulate a necessary condition for preventing contact.
What does the main body of the paper cover?
It covers the formulation of the mathematical model, the analysis of specific vehicle configurations (front and rear wheel scenarios), and the practical application of the model to existing car models in India.
Which keywords best characterize this work?
Key terms include ground-clearance, wheel-base, scrape-susceptibility, and speed-bump navigation.
Why is the wheel-base significant for long speed-bumps?
When a speed-bump is longer than the wheel-base, the rear wheels may start climbing the ramp while the front wheels are still on it, which can lift the vehicle's lowest point and reduce the required ground clearance.
Does the wheel radius influence the figure of merit?
Within the derived first-order model for a necessary condition, the figure of merit is found to be independent of the wheel radius.
What practical conclusion does the author reach regarding car selection?
The author concludes that when other factors are equal, buyers should select a vehicle with a smaller figure of merit value to minimize the risk of scraping.
- Citation du texte
- Venkatnarayan Hariharan (Auteur), 2017, Design considerations for ground-clearance and wheel-base for navigating non-standard speed-bumps, Munich, GRIN Verlag, https://www.grin.com/document/358591
