Vehicle Speed Control Using Road Bumps

Abstract

Road bumps play a crucial role in enforcing speed limits, thereby preventing overspeeding of vehicles. It significantly contributes to the overall road safety objective through the prevention of accidents that lead to deaths of pedestrians and damage of vehicles. Despite the importance of road bumps, very little research has been done to investigate into their design. While documentation exists on quantitative descriptions of road bumps, they offer little guidance to decision making. This work presents a unique approach to solving road bumps design problems. The results of our study reveal three important road bumps variables that influence the control of vehicle speeds. The key variables are bump height, bump width, and effective distance between two consecutive road bumps. Since vehicle speed control is the ultimate aim of this study the relationship between vehicle speed and other variables earlier mentioned is established. Vehicle speed is defined as the product of frequency at which a vehicle is moving over road bumps and the sum of effective distance between two consecutive road bumps. In the determination of bump height we assume a conical shaped curve for analysis as a matter of research strategy. Based on this, two stages of motion were analysed. The first concerns the motion over the bump itself while the second relates to the motion between two consecutive road bumps. Fourier series was then used to formulate a holistic equation that combines these two stages. We used trigonometric functions to model the behaviour of the first stage while with the second stage giving a functional value of zero since no changes in height are observed. We carried out vibration analysis to determine the effect of road bumps on a vehicular system. Arising from this a model component is referred to as an isolation factor. This offers guidance to the safe frequency at which vehicles could travel over road bumps. The work appears to contribute to knowledge in road bump research through the development of a novel approach to the control of vehicle speeds. Significant research progress could be made if engineering and academic communities at large appreciate our viewpoints. With this work it is apparent that varying of the assumptions made in terms of bump shape may produce high proliferation of beneficial research studies. Although this work may reveal a new way of investigation into road bump research, no claim is made for the work comprehensiveness. We expect experts to challenge some of our thoughts and ideas presented in this work.

The Effect of Speed Humps on Instantaneous Traffic Emissions

“…They measured emissions with mobile laboratory equipment at five locations with speed humps installed in pedestrian crossings to reduce vehicle's speed. Speed humps with trapezoidal shape are frequently found at pedestrian crossings, meanwhile speed bumps have semi-circular shape and are more abrupt than speed humps [24,34]. Januševičius and Grubliauskas [18] found rising concentrations of CO 2 and NO x near the speed humps and bumps with increments from 1 to 8 times for NO x , and from 1 to 5 times for CO.…”

“…They reduce the speed of vehicles by forcing the drivers to decelerate when encountering them, then once passing over them drivers may accelerate if there are no vehicles or obstacles ahead. Although their effect on traffic flow and pedestrian safety has been widely studied [21][22][23][24][25], there are few studies on their effect on air quality and pollutants generation. Some works monitor pollutants using specialized equipment mounted on cars or installed at control sites [1,2,9,[18][19][20]23].…”

Speed Responses to Speed Humps as Affected by Time of Day and Light Conditions on a Residential Road with Light-Emitting Diode (LED) Road Lighting

“…For example, speed humps have been shown to reduce speed by 43-63% on residential roads with a posted speed limit of 40 km/h [5] and to have varying effects, from reducing speed by 39% to increasing speed by 4%, on roads with various posted speed limits [8]. The speed-reducing effects of speed humps and bumps have been thoroughly studied and modelled in previous research (e.g., [4,[9][10][11][12]). Speed humps have also been proven to be effective in reducing the number of collisions between motor vehicles and pedestrians, especially children [13,14].…”

Raised Pedestrian Crossings: Analysis of Their Characteristics on a Road Network and Geometric Sizing Proposal

“…However, local authorities are not using in an appropriate manner both SCUs [14] and RPCs, and there is a lack of regulations on traffic control design [27]. Likewise, exhaustive and long-term studies on the implementation of both in areas with powered two-wheelers (PTWs) are still lagging behind, in spite of the need for such knowledge for fine-tuning the economic assessment of risks and maintenance programs associated with this mode, which although reliable, do not consider effects of traffic calming on PTWs [23,24].In the literature, several studies about the effect of geometric design criteria of SCUs (i.e., slope, height, and length) and their effectiveness in reducing vehicle speed are available [14,[28][29][30][31][32]. SCU studies show that drivers approaching a hump reduce vehicle speed in order to mitigate the discomfort caused by the vertical accelerations in the vehicle overpassing the SCU.…”

“…In the literature, several studies about the effect of geometric design criteria of SCUs (i.e., slope, height, and length) and their effectiveness in reducing vehicle speed are available [14,[28][29][30][31][32]. SCU studies show that drivers approaching a hump reduce vehicle speed in order to mitigate the discomfort caused by the vertical accelerations in the vehicle overpassing the SCU.…”