Traumatic brain injuries constitute a significant portion of injury resulting from automotive collisions, motorcycle crashes, and sports collisions. Brain injuries not only represent a serious trauma for those involved but also place an enormous burden on society, often exacting a heavy economical, social, and emotional price. Development of intervention strategies to prevent or minimize these injuries requires a complete understanding of injury mechanism, response and tolerance level. In this study, an attempt is made to delineate actual injury causation and establish a meaningful injury criterion through the use of the actual field accident data. Twenty-four actual field head-to-head collisions that occurred in professional football games were duplicated using a validated finite element human head model. The injury predictors and injury levels were analyzed based on resulting brain tissue responses and were correlated with the site and occurrence of MTBI. Prediction indicated that the shear deformation around the brainstem region could be an injury predictor for concussion. Statistical analyses were performed to establish the new brain injury tolerance level and to further reduce brain injury severity.

An improved and detailed 3-D FE model of human cervical spine was created using digitized geometric measurement. The model was validated with the in-vivo studies of Moroney, Panjabi and Fuller. Clinical instability of the spine for two cases involving flexion and compression loading (simulating injuries in motorcycle vaulting, football and diving accidents) were analyzed. The instability was based on the check list of Panjabi and White. It was determined that flexion moment of 10 Nm or compressive force of 500N result in the onset of clinical instability.

The study deals with boring tool, which was found to exhibit chatter in fine boring operation occurring at high frequencies, more than 10,000 Hz, and causing reduced tool life. The boring tool was operated in a stage of a transfer-type machining equipment and used for making small diameter hole, 15mm (0.59in), in a hardened alloy steel of motorcycle engine component. The objective of the research is to identify the mechanism responsible for the onset of the high frequency chatter. To study the mechanism, cutting tests have been performed in analogous machining operation, as well as structural dynamics examination of boring tool using experimental modal analysis by sinusoidal excitation. The experimental study has revealed that the traditional knowledge of regenerative chatter can not fully explain the chatter mechanism, but the effect of regeneration, the imaginary part effect of inner modulation, and the X-Y looping of the tool tip are three relevant characteristics in the onset of the chatter. Those findings are included in a new theoretical chatter model of which validity is evaluated principally by computational analysis of energy supplied and dissipated in the cutting process-boring tool structure system per vibration cycle.

Silent chains have extensively replaced roller chains in drive systems owing to annoying noise problems. But, for some types of cab-motorcycles, especially sheet-frame cabs, the annoying noise originated from silent chains can still not been accepted. In this study, silent chain noise of cab motorcycles has been well investigated by firstly the order analysis and time-frequency analysis of measured noise, and secondly the analysis of origination and transmission of noise. Therefore, noise mechanism can be precisely uncovered and understood. Some experiments were conducted to discover three primary issues of a noise problem, i.e., noise source, transmission path, and response. In addition, to explain a noise component resulting from structure resonance, the mode shape at 1640 Hz was constructed based on the running mode principle. Different engineering modifications have been validated to reduce this transmission-part noise. Useful proposals can be concluded as design guidelines.

In the design of driving systems, silent chains have extensively replaced roller chains thanks to annoying noise problems. But, for some types of cab-motorcycles, especially sheet-frame cabs, the annoying noise originated from silent chains can still not been accepted. In this study, silent chain noise of cab motorcycles has been well investigated by firstly the order analysis and time-frequency analysis of measured noise, and secondly the analysis of noise-origination, transmission and amplification via frame. Thus the noise mechanism can be precisely uncovered and understood. Some experiments were conducted to discover three primary issues of a noise problem, i.e., noise source, transmission path, and response. In addition, an odd mode shape, i.e. mode (1,3), was constructed based on the running mode principle. Then, a dominant noise component resulting from structure resonance can be interpreted. In the study, different engineering modifications have been validated to reduce this transmission-part noise.

The average speed of European City traffic is less than 12 miles per hour and the vast majority of journeys are less than two miles. It seems reasonable therefore to devise an environmentally friendly vehicle with low or zero emissions to serve a market that requires safe but manoeuvrable transport with a small road footprint. Working with European colleagues in industry and academia a narrow track three-wheeled vehicle with crash protection, partial enclosure, electric drive and lightweight construction has been developed to the prototype stage. In this paper the design evolution of a tilting mechanism for this narrow track vehicle which provides locking of the tilt axis at low speed and variable damping at high speed is presented. Active and passive alternatives are discussed and a passive alternative is chosen on the basis of cost and safety. A range of actuation and speed sensing mechanisms are compared and a solution identified which is simple, low power, low cost and controllable. The system uses appropriate technology with a low maintenance requirement that is both compact and lightweight. Despite the potential for good reliability the system is designed to be fail safe; it is of paramount importance that the vehicle be allowed to tilt freely rather than become locked once the speed has risen above that required to balance. The driving style required at low speed, when the tilt axis is locked, will be different to that required at higher speeds, when the handling will be similar to that of a standard motorcycle. However the low lateral accelerations associated with low speed manoeuvres should make the change in driving style imperceptible and a degree of rear wheel steering, introduced as a result of the tilt axis, should improve mid-speed manoeuvrability. Having an estimated sale cost of $7000 the vehicle would be suitable for personal transport or a carrier of light loads in city environments.

Traumatic brain injury (TBI) constitutes a significant portion of all injuries occurring as a result of automotive, motorcycle and sports related injuries. Over the years, a large amount of literature has been devoted to an increased understanding of clinical symptoms, pathological evidence and injury biomechanics for such injuries. However, the precise causal mechanism, which accounts for complex mechanical interactions and responses in an anatomical structure as complex as the brain, is not fully understood.

Motorcycles have been a mode of transportation since 1894, when the first batch of motorcycles were manufactured for consumer use by Hildebrand & Wolfmüller. Motorcycles provide a fast and cost effective, specifically fuel economy, way to commute. They are also used in recreational settings such as motocross and performance racing activities. Over the years, there have been many different design generations for the various manufactures and custom shops. The customer demand for motorcycles is always increasing as well. However, the biggest drawback to someone owning and operating a motorcycle has always been safety concerns. One of these safety concerns is the motorcycle falling over and being damaged while being parked. Fall overs occur for a multitude number of reasons, the most common occurrences due to being parked on an uneven level or someone pushing the motorcycle over. Current safety devices to prevent this from occurring are crash bars and center stands. However, these devices are either not applicable to all motorcycle makes and models or do not appeal to the motorcycles look per the owner’s discretion. A “no fall over” automated mechanical kickstand would solve both of these problems and, at the same time, prevent fall over accidents.

There are almost 9 million motorcycles registered only in the United States, while in other much smaller countries such as Colombia, this number can exceed 8 million. However, the population of Colombia is about six times smaller than the population in the United States. This demonstrates that for many people around the world, motorcycles are a great transportation method, which at the same time can provide a solution to the problems of urban traffic and scarcity of parking space. In addition to the problems associated with traffic, there are also public health problems related to the air pollution generated by internal combustion engines in motor vehicles. The issue of greenhouse gases emission from motor vehicles is being tackled by electric propulsion systems. The massive use of electric vehicles can have a strong positive impact in the quality of life of people and the environment. Therefore, electric motorcycles can become an optimal solution for transportation, by reducing the problems of urban traffic and space, while also being friendly with the environment. Two ways to help popularizing these vehicles are by reducing their cost and improving their performance. This work focuses on the optimization of the suspension system which is one of the key components of a motorcycle. The main function of the suspension system is to provide safety and comfort to the riders, two conditions that must be guaranteed in a good design. This article proposes a methodology for the optimal design of a motorcycle suspension, considering the different phases of development, starting with the geometric design, where the different parameters are determined for the front suspension, such as Rake Angle and Trail, and for the rear suspension, such as the inclination and the geometry of the swing arm system. Next, the detailed design is carried out, making sure that the elements of the suspension coincide with the dimensions at the attachment points to the chassis. Once all the geometry is available, the kinematic analysis is carried out, to assess the behavior of the system during the wheel trip. A structural analysis is performed to evaluate stresses, stiffness and resonance frequencies of the system, and to evaluate the minimum safety factor of the structure under the action of typical loads. With the final geometry of the system, a lumped parameter model can be obtained to rapidly observe its transient behavior under the effect of different irregularities that may be encountered on the road, which lead to the optimization of the parameters that offer greatest comfort to the rider. This set of parameters was used as inputs for the representation of the system in the physical modeling simulation interface Simmechanics ® to generate final performance graphs. The results obtained with this methodology covered the different aspects that must be considered in the design of an important part of a transportation system such as an electric motorcycle.

Automobile Braking System is one of the most important sub systems of the vehicle. It is the primary safety system since the stopping of the vehicle is majorly dependent on this system. This system utilises the frictional force between the tire and the road to stop the vehicle. The braking force required by the vehicle is governed by two factors. One of them is the coefficient of friction between the tire and the road surface, the other one is the load on the vehicle. Thus, required braking force to halt the vehicle with the minimum possible stopping distance varies with the load in the vehicle. If the applied braking force is greater than the required brake force, wheel gets locked which results in increased stopping distance. In order to prevent the wheel lock at low load conditions, a variable braking force system is developed. In Motorcycles, the pillion load majorly contributes to the overall weight. Thus, the amount of braking force required to stop with minimum stopping distance also varies drastically with respect to pillion load condition. Hence, the amount of braking force developed between the road surface and the tire is varied in the variable braking force system. In this project, variable brake force system is achieved by varying the effective disc radius. The maximum braking force developed between the ground and the tire is controlled based on the pillion load on the motor cycle, if friction is present between the tire and the ground. Two calipers are mounted on the brake disc of which one is fixed at a constant distance (constant effective disc radius – 67mm) and the other is movable depending on the load on the motorcycle. The movable caliper slides upwards and downwards such that the effective disc radius is varied based on the pillion load. Using a load cell, the load of the vehicle is determined. A microcontroller is programmed to move the caliper with the help of a stepper motor based on the load on the motorcycle. This way, the effective disc radius is varied for various loads on the motorcycle.

This work was focused on the development of a hybrid engine which was fueled with three different fuels; gasoline as original fuel, Liquid Petroleum Gas (LPG) and biogas as two alternative fuels. The developed engine consisted of fuel storage tanks, a small gas reducer, a fuel premixer and the engine of a Suzuki Skydrive 125CC motorcycle. Performances of the prototype and developed engines were compared in terms of wheel speed. The developed engine could be started, idled and accelerated with the average maximum speed of 1276 revolutions per minute when it was connected directly with the biogas reservoir. Then, the biogas was compressed and stored in a standard gas tank which was connected with the developed engine, the average maximum speed of 1273.67 revolutions per minute was obtained from three experiments. This work emphasized not only biogas usage as the alternative fuel for the engine but also pointed out that biogas quality could affect the engine performance. The developed engine could be applied as vehicle engine or it could drive household self-power generators by using household biogas as fuel.

An investment firm located in Peru has partnered with Western New England University to develop a novel, motorcycle mounted fast food delivery system for international markets. The project afforded students the opportunity to work on an international product development team, exposing them to the design requirements and constraints of international customers and companies. The often damp and cool climate in many countries makes food prone to becoming soggy during delivery as the moisture escaping from the hot food quickly fills the food containers and delivery box mounted to the back of the motorcycle, saturating the food. Delivery times, often in excess of 45 minutes, can also cause the food to become cold, resulting in decreased customer satisfaction, product returns and lost business. The project was conducted over a three year period using nine mechanical engineering students. The project began in 2014 when a team of two students was tasked with developing a benchtop method of keeping food hot and preventing it from becoming soggy while being delivered. They determined that the use of ceramic heaters and small fans effectively kept the food warm and dry. In 2015, two teams of two students competed to develop a box design with integrated heaters and fans which could be powered using an alternator mounted to a delivery motorcycle. While effective fans and heating elements were found, it was decided that the mounting of an additional alternator was cumbersome and motorcycle dependent, rendering the concept poorly suited for field installations. In 2016 another team of two students integrated a hand-made lithium ion Battery pack and two 300W ceramic heaters and computer fans into a production delivery box. While the system maintained food quality for up to 50 minutes, the battery pack was unable to reliably provide the required power to the system. Finally, in the fall of 2016, a student improved this design by improving the heater and fan performance while adding urethane insulation into the box. Temperature was controlled using a commercially available thermistor, and all components were integrated into a retrofit kit which could be installed by a technician in the field. The power requirement was reduced by over 50% and the system operated for 110 minutes using two, commercially available 27 Ah lithium iron phosphate batteries. Students gained global perspective of the product development process as they experienced the effects of various cultures on the requirements of customers and the international design and marketing team.

For the vehicle to move forward, the engine has to be connected to driving wheels so as to propel the vehicle. The engine rotates at relatively high speeds, while the wheels are required to turn at slower speeds. The torque requirements of the vehicle vary as per the prevailing conditions of load, terrain etc. Gear box provides different gear ratios between the engine and the driving wheels, to suit the varying road conditions such as when climbing hills, traversing rough road, moving on sandy road or pulling a load. The required gear shift for providing varying torque requirements can be obtained either manually or automatically. Automatic gear shifting mechanism is a concept implementing an embedded control system for actuating the gears automatically without human intervention. The automation is achieved by using a microcontroller and suitable sensor and actuator hardware. Whenever the speed of the vehicle increases or decreases beyond a pre-defined set of values, the microcontroller based control system actuates the clutch as well as the gear and helps maintain a steady operation of the automobile. The concept of automatic gear change is applied in this work to a 4-stroke, manual transmission motorcycle. The clutch is actuated by means of a DC Motor actuated mechanism and gear lever is actuated by means of the spring loaded solenoid actuator, both controlled by a microcontroller based circuit, programmed to read the signals from an inductive proximity sensor which senses the actual speed of the wheel. The system design and development is described in this paper with control circuit and control logic.

Motorcycle helmets are vital to protect from recurrent road accidents as they prove crucial in reducing brain trauma. This research piece presents a new and plausible bio-inspired design affined to the foam liner material and structure in helmets. The proposed liner design is inspired from animal horn micro-structure and tubule arrangement. An innovative drop-testing apparatus is presented with a spring-ratchet mechanism for experimental testing. The aim is to validate the new design by meeting the ECE 22.05 standard for motorbike helmets using peak linear acceleration and HIC criteria. Experimental results are partly verified against FEA simulations for two proposed samples. Further samples call for more complex simulations at a later stage to best describe material properties and structures.

Modern methods for analyzing motor vehicle deformation rely upon a force-deflection analysis to determine deformation work energy. Current methods provide acceptable accuracy when calculating the velocity change of vehicles involved in a collision but require significant modification to accommodate oblique and low-velocity collision events. The existing algorythms require vehicle-specific structural stiffness coefficients for each colliding vehicle, determined from full-scale impact testing. The current database of vehicle structural stiffness values is generated mainly through government safety standard compliance testing and is quite extensive for frontal impacts involving passenger cars and many light trucks and SUVs. However, the database is devoid of specific crash testing necessary for deformation analysis of rear and side structures of many vehicles. Additionally, there remains a dearth of structural stiffness coefficients for heavy commercial vehicles, buses, recreational vehicles, heavy equipment and motorcycles, rendering the application of the current force-deflection analysis approach useless for many impacts involving such vehicles. The research presented, known as the Generalized Deformation and Total Velocity Change System of Equations , or G-DaTA ΔV ™, develops an accurate, reliable and broadly-applicable system of equations requiring knowledge of the structural stiffness coefficients for only one vehicle, rather than both vehicles involved in a collision event, regardless of the impacted surfaces of the vehicle. The developed methodology is inclusive of non-passenger vehicles such as commercial vehicles and even motorcycles, and it also accommodates impacts with objects and surfaces not supported by the current structural stiffness coefficient database. The G-DaTA ΔV ™ system of equations incorporates the linear and rotational collision contributions resulting from conservative forces acting during the impact event. The contributions of the G-DaTA ΔV ™ system of equations are as follows: 1. Consideration of non-conservative contributions from tire-ground forces and inter-vehicular frictional energy dissipation commonly present during non-central collision configurations. 2. Ability to solve for collision energy of a two-vehicle system using a single structural stiffness for only one of the colliding vehicles using work/energy principles. 3. Determination of the total velocity change for a vehicle resulting from a given impact event, which results from conservative and non-conservative force contributions. 4. The ability to predict the time period to reach maximum force application during an impact event, allowing for the determination of the peak acceleration levels acting on each vehicle during an impact. The results of applying the G-DaTA ΔV ™ to full-scale impact tests conducted as part of the RICSAC collision research will be presented. Additionally, analysis of real-world collision data obtained through the National Automotive Sampling System demonstrates a close correlation with the collision values recorded by the vehicle event data recorders (EDRs) as part of the supplemental restraint system airbag control moducles (ACM). Compared to other analysis methods currently used, determining the total velocity change of a vehicle due to a collision event is achieved with a higher level of both accuracy and precision when using the G-DaTA ΔV ™. The generalized approach of the G-DaTA ΔV ™ applies to collisions ranging from the simple collinear impact configuration to the most rigorous conditions of offset and oblique impacts. The comprehensive formulation provides greater utility to the researcher or forensic analyst in determining the contributions of the vehicle-roadway-driver environment as it relates to real-world collision events and their effects on vehicle and highway safety.

For the vehicle to move forward the engine has to be connected to driving wheels so as to propel the vehicle. The engine rotates at relatively high speeds, while the wheels are required to turn at slower speeds. The torque requirements of the vehicle vary as per the prevailing conditions of load, terrain etc. Gear box provides different gear ratios between the engine and the driving wheels, to suit the varying road conditions such as when climbing hills, traversing rough road or sandy road or pulling a load. The required gear shift for providing varying torque requirements can be obtained either manually or automatically. Automatic gear shifting mechanism is a concept implementing an embedded control system for actuating the gears automatically without human intervention. The automation is achieved by using a microcontroller and suitable sensor and actuator hardware. Whenever the speed of the vehicle increases or decreases beyond a pre-defined set of values, the microcontroller based control system actuates the clutch as well as the gear and helps maintain a steady operation of the automobile. The concept of automatic gear change is applied in this work to a 4-stroke, manual transmission motorcycle. The clutch is actuated by means of a DC Motor actuated mechanism and gear lever is actuated by means of the spring loaded solenoid actuator, both controlled by a microcontroller based circuit, programmed to read the signals from an inductive proximity sensor which senses the actual speed of the wheel. The system design and development is described in this paper with control circuit and control logic.

The purpose of this project is to develop a motorcycle rear swing arm using finite element analysis and response optimization. This paper aims to discuss the specific features, benefits, and precautions when using design optimization to develop a specific project. Design Optimization has been an evolving process for many years. The latest versions of finite element software allow users to develop, analyze, and optimize structural designs within one program quickly and efficiently. A single shock absorber mounted close to the chassis and centrally located was the design selected to be analyzed. The design was selected for use in a variety of motorcycle types. This project consisted of a unique set of design attributes that were ideal to exemplify design optimization techniques. Static structural models were created to refine the design before using response optimization. These models finalized the material selection and initial sizes. A central composite design type was generated with selected boundary conditions for four parametric dimensions of the model. The ideal design of this component would include the resulting stress below a safe allowable value, minimal deflection, and the least amount of weight. It is evident that these three parameters will oppose one another as geometry is changed. Conceptually, an ideal candidate can be created that is a balance of the three parameters. Using the parameters of the selected candidate, a new model was generated for analysis. The final model was further refined by removing unnecessary material that was identified in the structural models. The first step in a thorough optimization is generating an appropriate amount of design parameter values that are an acceptable representation of all the possible outcomes, or design of experiments (DOE). The DOE tool used to generate the parameters in this project was central composite design (CCD), since it is the most appropriate for second order response models [1]. The second order relationship was confirmed using a trade-off plot. The two level, four input parameter DOE produces twenty five potential candidates that were refined using response surface. The response surface method used in this design process [2,3] to make judgement calls on the final design is examined during this development, and proves useful. Initial static structural models are created and used to set up the model for optimization. Material selection was also accomplished in this phase of development. This process aides in the overall design process by identifying areas of concern as well as the range of parameters that will be analyzed. Multiple acceptable candidates were selected through the use of the optimization tools and a final candidate was selected based on the output of the design attributes and the values of the corresponding parametric geometry. The final selection was also made with the consideration for cost, ease of fabrication, and standardization.

In this contribution a complementarity formulation for the solution of EHL problem in presence of cavitation is employed in order to investigate the tribological behavior of the conrod small-end of a high performance motorbike engine. The influence of different physical and geometrical parameters is discussed. In particular, the clearance between the conrod small-end and the piston pin, the lubricant physical properties, the surface roughness and the stiffness of the piston pin are investigated, thus providing preliminary guidelines for the correct design of the coupling. Due to the negligible influence of the transversal forces acting on the conrod small-end and of the relative sliding speed between the mating surfaces, a two symmetrical model of the assembly is prepared and results are compared with those obtained adopting a simply symmetrical model.

To prevent wheel lock up (and possible loss of control and capsize) during hard braking motorcycle manufacturers have equipped motorcycles with Antilock Brake Systems (ABS) either as an option or as standard equipment. Several studies utilizing real-world crash data have been published which estimate the effectiveness of motorcycle ABS in reducing the risk of a crash based on varying assumptions. These investigations have reported mixed results. The present investigation relies upon the Fatality Analysis Reporting System (FARS) and the Florida police-reported crash databases to further investigate the effectiveness of motorcycle ABS by expanding upon and refining previous approaches. Notably a case-control approach is used whereby crashes involving ABS- and non-ABS-equipped motorcycles are divided into five groups with a varying likelihood that ABS will affect the risk of crashes in that group. The group of crashes with the least likelihood of being influenced by ABS is considered the control group and used as a measure of exposure to crashes. This methodology attempts to reduce any selection biases that might exist in the two motorcycle classes. The results support the hypothesis that ABS is effective in reducing the crash risk in some crash types. However, it was found that the case-control approach does not incorporate all factors that might influence the overall effectiveness of ABS, for example, motorcycle class and operator age. Accounting for these additional factors would likely require the use of regression analyses and would benefit significantly from additional data.

The chatter phenomenon, appearing during high speed cornering maneuvers performed by racing motorcycles, consists of a self-excited vertical oscillation of both the front and rear unsprung masses in the range of frequency between 17 and 22 Hz. The suspensions are not generally able to dampen the above vibrations which start from the rear wheel and suddenly propagate to the front wheel during the corner entry phase, making the vehicle’s handling unpredictable and, ultimately, weakening the overall performance, that is the lap time. It is not clear which is the determining factor causing this phenomenon. Therefore, numerical simulation on a three dimensional, multibody motorcycle model is proposed, taking into account the effects of the major parameters involved, in order to highlight which of them takes part in the vibration. Accurate models for tire and drivetrain have been developed, making it possible to consider tire carcass deformability, chain transmission in both traction and braking states, full drivetrain inertia and anti-hop clutch effect. A critical maneuver experimentally measured on the race track is analyzed. The modal response of the linearized system is evaluated for several configurations extracted from the maneuver. The above maneuver is then simulated with the model, showing the actual vibration uprising. A critical discussion of the possible physical interpretations of the phenomenon is given.