Motorcycle Behavior Research Articles

Effects of layout design changes on frontal crash behaviour of small motorcycles

ABSTRACTMotorcycle frontal crashes always cause serious and fatal head injuries to riders, and the behaviour of riders was known to be influenced by the behaviour of the motorcycle during crashes. Thus the present work was carried out with the main objective to study the effects of changes of layout design of a small motorcycle, particularly in regards to the arrangement of the engine block and air filter casing, on its behaviour in frontal crashes. The study was performed via finite element simulations using a motorcycle model with fully functional and deformable front wheel and fork structures. A two-level factorial experiment approach, 23, was used for the parametric study design, with the peak magnitude of horizontal and vertical accelerations of the motorcycle in the crash as response variables. The key peak magnitude of both the acceleration components which were found to be substantially affected by the layout changes showed the differences of 26.8% and 43.9% between the designs that yield the lowest and highest accelerations, respectively, for the horizontal and vertical accelerations. Empirical models for predicting the peak magnitude of the corresponding accelerations were established and the effect plots were also produced. The crash behaviour of the motorcycle in relation to the crash safety was discussed and it was concluded that the behaviour of the motorcycle in frontal crashes could be enhanced for better crash safety by a proper design of motorcycle layout.

A New Instrumented Tool for Motorcyclist Behaviour Understanding: Application to Roundabouts

Today, there are increasingly more motorcycles on the roads and the number of motorcyclists killed is greater than the number of motorists killed. The safety of powered two wheelers (PTWs) is an important issue for public authorities and road administrators. In 2014, in France, PTWs represented only 2% of traffic, but 24% of accidents and 18% of facilities. European governments have made this particular point a priority for road safety for the next decade. Yet, they are vulnerable road users for which few studies have been conducted on their behaviour and interaction with road infrastructure. Observation of their behaviour and interaction enables public authorities to understand causes in order to propose actions to improve safety for this category of road user. In this context, we developed a new tool to analyse motorcyclist behaviour in relation to road infrastructure. This tool is a motorcycle with average engine capacity. It is fitted out non-intrusive sensors so that motorcyclists can ride in real conditions. The motorcycle is equipped with multi-sensor and multi-video architectures. Both architectures are synchronised, enabling qualitative data to be paired with objectives data. Data collected includes GPS position, three axial accelerations and rotations and motorcyclist actions on the motorcycle (for example, braking, flashing, etc.). The video architecture consists of three cameras. The first observes the motorcyclist's environment. The second is positioned on the motorcyclist's helmet to observe head movements and the third films the road surface to detect lateral position and give an idea of road conditions. The objective is to obtain quantitative data to analyse motorcyclists’ dynamics in relation to road infrastructure. The tool will also help to understand interaction between different road user groups, particularly interaction between motorists and motorcyclists. Results will enable road managers to take into account the coexistent status of motorcyclists and motorists. In this study, we focus on motorcycle behaviour on urban roundabouts. Experimentation with a panel of motorcyclists was conducted. The influence zone was determined using driving parameters.

Riding the Country, Buying the Brand: How Country-of-Origin Image Drives the Purchase Behavior of Big Motorcycle in Indonesia

This paper examines the role of country-of-origin image (COO image) values in the process of purchase decision making of big motorcycle consumers in Indonesia. Referring to the COO image values such as Authenticity, Differentiation, Quality Standard and Expertise, as well as the elements of purchase decision making process such as Need Recognition, Information Search, Evaluation of Alternatives, Purchase Decision and Post Purchase Decision, researchers conducted in-depth interviews to five Triumph big motorcycle consumers. The results show that the authenticity of the British-made product is the main consideration of consumers both in searching for information and in recognizing the need of big motorcycles. The competitive advantages of product that make it different from other products is the consideration in evaluating the brands, while product quality has the role in stimulating the purchase decision and post purchase actions, in which also strengthened by the perception towards the British-expertise in producing big motorcycles. This research is very beneficial to big motorcycle brands in understanding the mindset of Indonesian consumers.

Who are the big spenders at a motorcycle event?

Africa Bike Week, considered South Africa’s premier biking event, attracts large numbers of bikers, especially Harley-Davidson bikers, and bike enthusiasts from across the country. This study investigated these visitors and their spending behaviour. As background to the study, we provide a broad survey of the literature on socio-demographic and behavioural determinants of spending. Motorcycle tourism has received international research attention, especially in the US, but to date has been neglected in South Africa. Our study helps to fill this gap, particularly as regards biker and spectator characteristics. We found that more behavioural than socio-demographic variables influenced spending at this event. Visitors’ motorcycle behaviour and group composition had a significant effect on higher spending. The analysis identified three new determinants of spending: the travel motives lifestyle, event attractiveness and event novelty. Event organisers can use this information to increase spending and enhance the economic impact of motorcycle tourism in South Africa.

Exhaust emissions of new high-performance motorcycles in hot and cold conditions

An experimental–analytical investigation on the emissive behavior of two high-performance motorcycles belonging to the most recent European legislative category was being performed by the Department of Industrial Engineering of the University of Naples Federico II. The study was focused on these vehicles because the pertinent information was not very exhaustive in the scientific literature, with particular reference to the assessment of cold-start extra emissions of this particular two-wheeler vehicular class (Euro-3 legislative category and displacement >750 cm3), that is playing a rising central role in private mobility, also in urban context. From this motivation, in this study a calculation procedure was designed and optimized to model the cold-start transient behavior of motorcycles; through this methodology, it is possible to evaluate the cold transient duration, the emitted quantities during the cold phase and the relevant time-dependence function. The whole procedure was applied on the carbon monoxide and unburned hydrocarbon exhaust cold extra emissions of the selected motorcycles, which were measured on the chassis dynamometer. Experimental tests were performed in cold and hot operating conditions, during both driving cycle regulated by law and real-world driving cycles.

Cold Start Emissions of a Motorcycle Using Ethanol-gasoline Blended Fuels

The object of this study is to investigate the effect of ethanol–gasoline blends on CO and HC cold start emissions from a four- stroke motorcycle. Nowadays, due to catalyst improvements and efficient electronic mixture control, a significant part of the total emissions during a trip takes place during the cold phase. The employ of alternative fuels could be one of means to lessen the cold-start emissions from two-wheeler engines: ethanol is known as potential alcohol alternative fuel for spark ignition engines, which can be blended with gasoline to increase oxygen content and then to decrease CO and HC emissions.From this considerations, an experimental-analytical investigation was performed on the exhaust cold extra emissions of one motorcycle belonging to the Euro-3 legislative category. The study explains a calculation procedure to model the cold start transient behavior of motorcycles in order to evaluate the impact of ethanol addition (10, 20 and 30 vol.%) on cold start emissions compared with a reference commercial gasoline. Results of the tests indicate that CO and HC cold start extra emissions by using ethanol–gasoline blended fuels decrease compared to the use of unleaded gasoline. Emission factors during the cold start transient were quantized as a function of the ethanol percentage in the blended fuels.

The Computational Multi-Body Dynamics for Motorcycle on its Oscillation Properties

Based on 3D digital model of motorcycle constructed in UGNX, motorcycle multi-body model was established for dynamic behavior analysis under inbuilt assembling of coefficient matrix of dynamical equation in computation code of ADAMS. Through the comparison of simulation analysis for dynamics of different models in accelerations in time and frequency domains, it is concluded that realistic multi-body model better represents the dynamic behavior of motorcycle while simplified one with less physical parameters only provides qualitative analysis for the dynamic behavior. The simulation results shows that model IV with accurate parameters of components influences the dynamic response of frame, simplified models could not represent the influence of mass and inertia moment of subsystems on dynamic behavior, which means advanced motorcycle multi-body improves simulation effectiveness and approximates the dynamic behavior of motorcycle well so that the simulation developed to replace experiments in bad working conditions will promote the advancement of engineering.

A Full Scale Motorcycle Dynamic Rig

Knowledge of “out of plane” modes is very important when defining the dynamic behavior of a motorcycle and its stability and handling in particular. Several mathematical models are available in the literature to study and preview frequency, damping and stability of these modes but, in order to verify these values, road tests must be performed which are sometimes dangerous for the tester. A test rig to evaluate the possibility of performing a dynamic characterization of the out of plane modes instead of road tests, was developed. The use of a test rig is certainly limited compared with road tests since the physical phenomena are not completely reproduced but allows tests to be extended to low and very high speeds and assures test repeatability. This paper presents the test rig and the results of an experimental investigation conducted on a scooter; the tests were conducted in steer free control condition with different inertia and tire characteristics.

Contribution to the Investigation of Motorcyclists’ Speed Prediction Equations for Two-Lane Rural Roads

The calculation of speed prediction equations has been the subject of numerous researches in the past. The majority of them present models to predict free-flow speed in terms of the road geometry at the curved road sections and more specifically in terms of the radiuses of the curves. Common characteristic is that none of them approaches the speed behavior of motorcycles since they are excluded from the datasets of the various studies. Instead, the models usually predict operating speed for other vehicle types such as passenger cars, vans, pickups and trucks. The present paper aims to cover this gap by developing speed prediction equations for motorcycles. For this purpose a new methodology is proposed while field measurements were carried out in order to obtain an adequate dataset of free-flow speeds along the curved sections of three different two lane rural roads. The aforementioned field measurements were conducted by two participants incorporating various road conditions (e.g. light conditions, experience level, familiarity with the routes). The ultimate target was the development of speed prediction equations by calculating the optimum regression curves between the curve radius’ and the corresponding velocities for the different road conditions. The research revealed that the proposed methodology could be used as a very useful tool to investigate motorcyclists’ behavior at curved road sections. Moreover it was feasible to draw conclusions correlating the speed adjustment with the various driving conditions.

Motorcycle speeds at urban intersections

BackgroundDrivers at fault cause approximately 40% of all motorcycle crashes in New Zealand.AimTo identify relative speed of cars and motorcycles in an urban setting.MethodsFive urban, uncontrolled T-intersections known to be...

Impact of Pavement Defects on Motorcycles’ Road Safety

Degradation of the pavement has a significant impact on road safety and, in particular, asphalt polishing turns out to be very hazardous for powered two wheelers. The paper reports the results of a study aimed at analysing the effects of asphalt polishing of pavements on the dynamic behaviour of motorcycles. A dynamic simulation code was used in order to understand the motorcycles dynamics parameters in different conditions, define a model of the dynamic behaviour of motorcycle and propose a useful tool for planning maintenance interventions based on the risk associated to the asphalt polishing of the pavement.

Motorcycle and scooter speeds approaching urban intersections

Five urban, uncontrolled T-intersections known to be motorcycle crash ‘black spots’ were monitored using instrumentation and a roadside observer. Two sets of twelve-hour observations were collected for each site (N≈100,000). Instrumentation recorded the ‘events’ of vehicles passing to measure, speed, direction, lane position, vehicle type (broadly characterised) and headway. Observers further recorded times of bicycle events, type of motorcycle (scooters or motorcycles), the behaviour of motorcycles and the use of ‘high conspicuity’ gear such as clothing or helmets. Results establish that motorcycles travel around 10% faster than the other traffic (car mean speed=34.97km/h), with motorcycles travelling on average 3.3km/h faster than cars. Motorcycles were 3.4 times more likely to be exceeding the speed limit than cars. Similar results are described for scooters. Also examined are the influences on mean speeds such as the time of day, the presence of a car at the t-intersection, and the influence of free headway. The results are compared for robustness across locations and days. It is concluded that in urban areas motorcycles are travelling significantly faster than other traffic. These findings are discussed against a concern to reduce motorcycle crashes by improving conspicuity and previous research that implicates a ‘looked-but-failed-to-see’ effect for car drivers.

The kinematic features of motorcycles in congested urban networks

The aim of this paper is to compare the kinematic features of motorcycles with those of passenger cars in urban traffic. The hypothesis that motorcycles’ capability to swerve in urban traffic contributes to their seemingly assertive behaviour is examined. Data for this study were collected in afternoon peak hours at Central London using video recorders. Detailed information on the trajectories of 2109 vehicles (including 477 motorcycles and 1293 passenger cars) was extracted from the video images and the observable kinematic features were analysed. In addition, a model describing the longitudinal following behaviour of motorcycles was employed to analyse the impacts of motorcycles’ swerving behaviour. The model was calibrated using Markov Chain Monte Carlo (MCMC) numerical methods. The observable kinematic features show that in comparison to passenger cars, motorcycles have shorter safety gaps, higher speeds and severer acceleration and deceleration rates reflecting their generally much higher power to weight ratios and usage of available braking power. However, the data also support the hypothesis that motorcyclists maintain a considerable safety margin as they have the ability to avoid a collision by swerving away.

New Approach to Modeling Mixed Traffic Containing Motorcycles in Urban Areas

Motorcycles constitute a significant proportion of traffic in many countries but are poorly represented in existing traffic flow theories and simulation software. A new approach to modeling mixed traffic is introduced focusing on depicting the movements of motorcycles. In this study, the characteristic patterns of motorcycle behavior were identified, and the key elements contributing to these patterns were extracted. Then three mathematical models were developed to depict these key elements, which were calibrated by using field data collected at Victoria Embankment in central London. After the calibration procedures, these models were integrated into an agent-based simulation model system. The ability of the simulator to reproduce plausible patterns of car and motorcycle behavior was verified. A number of potential applications of this simulator for the management of mixed traffic streams in urban areas are discussed.

THE SPEED, FLOW AND HEADWAY ANALYSES OF MOTORCYCLE TRAFFIC

Although much knowledge about traffic characteristics was acknowledged, very little attention has been paid regarding motorcycle. The purpose of this study addresses a comprehensive analysis of motorcycle behavior and operation through videotaping of some roads that have significant motorcycle proportion. Four locations in Hanoi, Vietnam have been found to meet criteria for data collection, including exclusive motorcycle lanes, mixed traffic and undivided roadways. Speed—flow relationships were developed for all locations, in which the adjustment factor for the present of vehicles other than motorcycle was based on motorcycle equivalent unit. Statistical analyses of the empirical data were utilized to demonstrate the characteristics of motorcycle speed, time headway regarding to traffic flow. The present paper provides a basic understanding of characteristics of motorcycle traffic. The finding obtains from this research may be used to develop new procedures for Highway Capacity Manual (HCM), which adapt developing countries as well as provide the data needed to develop a motorcycle simulation model.

An Analysis of the Motorcycle Behaviors on Road Shoulders at the Two-Way Two-Lane Trunk Roads

At the trunk roads which long distance traffic and short distance traffic are mixed, many types of vehicles are running on the limited roadway space and it is easy to generate the traffic conflicts and the traffic accidents. This research focuses the motorcycle behaviors at the two-way two-lane trunk roads which many motorcycles and many four-wheel vehicles are running. It aims to analyze the relationship between the width of road shoulder and the behaviors of motorcycles and four-wheel vehicles.

Analysis of Passenger's Posture Change Effect on Motorcycles and Disturbance Rejection Control

In 2005, the ban on riding tandem on motorcycles along expressways in Japan was lifted. Since this is likely to increase tandem riders, there is a need to improve the motorcycle stability of tandem riding from the perspectives of safety and comfort. A motorcycle becomes unstable at low speed. Thus, this study investigates the stability and handling properties in tandem riding on motorcycles at low speed. First, we did experiments and obtained the time responses of motorcycle behaviors and rider control after a passenger changes posture. Next, we constructed a multi-body model for a human-motorcycle tandem riding system that contains a controller that imitates the rider's driving operation. From simulation results, we obtained the effect of passenger's posture changes and such individual differences as upper-body mass and length. Finally, we designed a control system that applies a sliding mode control theory to reduce the effects of passenger's posture changes. After comparing the rider control model and the sliding mode control, the latter shows better control. This system also has robustness to uncertainty of passenger properties.

Cellular automaton model for mixed traffic flow with motorcycles

A single-lane cellular automaton model is proposed to simulate mixed traffic with motorcycles. By performing numerical simulations under the periodic boundary condition, some density-flow relations and the “lane-changing” behavior of motorcycles are investigated in detail. It is found that the maximum car flow decreases because of the “lane-changing” behavior of motorcycles. The maximum total flow increases first and then decreases with increasing motorcycle density. Moreover, the transition of the total flow from the free flow to the congested flow is smooth in this model. The “lane-changing” rate of motorcycles will decrease to zero finally with the increase of the car density. But its evolutionary trend is considerably complex. Another interesting fact is that, with the increase of the motorcycle density, the “lane-changing” rate increases first and decreases later. This phenomenon is very similar to the findings in other papers on multi-lane car flows. The“lane-changing” is almost of no use in increasing the flow of motorcycles as the motorcycle density is small. But it distinctly causes the increase in the flow of motorcycles when the motorcycle density is sufficiently large, and in this density regime, the flow of motorcycles gradually decreases to the one given with the Nagel–Schreckenberg model for motorcycles with the increase of the car density. The simulation results indicate that it is necessary to set a barrier or a lane for separating the motorcycle flow from the car flow except in some special density regime.

Multi-body modelling and analysis into the non-linear behaviour of modern motorcycles

The stationary and periodic motion of a motorcycle under typical and extreme running conditions on a straight road and during cornering is investigated. The motorcycle model consists of six rigid bodies: a rear frame, a steering head with handlebar and the suspended part of the front fork, the unsuspended part of the front fork, a rear swing arm, and two wheels. The tyre force model deals effectively with large camber angles and combined longitudinal and lateral slips plus normal spin rate. The equations of motion are generated in a symbolic form by the multi-body dynamics program AutoSim. For analysing solutions of the equations of motion, the numerical continuation program AUTO 97 is employed. Bifurcation diagrams for a motorcycle running straight ahead or in a circle are presented and discussed. The motorcycle can have three basic modes of instability: capsize, wobble, and weave mode. The results indicate that aerodynamic drag has a tendency to make the wobble mode more damped and the weave mode less damped. The emerging bifurcating periodic solutions are mostly of the subcritical kind for the weave and of the supercritical kind for the wobble.

Description of Motorcycle Behaviors by Potential Model

The authors are attempting to develop the traffic simulation as one of tools for evaluating motorcycle safety measures. In this paper, we deal with a motorcycle behavior overtaking an on-street parking vehicle, which is the most basic behavior in model construction. With the critical point distributions derived from the longitudinal and lateral potential curves and the potential thresholds, a statistical method extracting the passing-start point and the turning-start point is proposed. Analyzing swept path data observed from the actual traffic flow, model parameters concerning the passing-start point which is the most critical point in the trajectory, are estimated and the model identification method is discussed.