A novel approach on range prediction of a hydrogen fuel cell electric truck C.Venkatesh - Manager - Product Development, Sustainable Mobility & Advanced Technologies Abstract: A novel approach on range prediction of a hydrogen fuel cell electric vehicle Abstract: Today's growing commercial vehicle population creates a demand for fossil fuel surplus requirement and develops highly polluted urban cities in the world. Hence addressing both factors are very much essential. Battery electric vehicles are with limited vehicle range and higher charging time. So it is not suitable for the long-haul application. Hence the hydrogen fuel cell based electric vehicles are the future of the commercial electric vehicle to achieve long range, zero emission and alternate for reducing fossil fuels requirement. The hydrogen fuel-cell electric vehicle range, it means the total distance covered by the vehicle in a single filling of hydrogen into the onboard cylinders.
Automation is expanding in every possible direction and it was only time before it reached the Automobile sector. There has been tremendous traction towards autonomous cars since last 2-3 yrs as a probable solution to reduce accidents and promote safe and comfortable commute. Many companies have expressed their interest in developing some part(s) of it and when would all of this culminate resulting in a fully autonomous car. But as every coin has two aspects so same does automation. This paper covers the future of autonomous cars from Indian perspective, covering possible challenges, complex use cases, advantages, technology enablers, economy outlook etc. India has the dubious honor of ranking first in road deaths in the world at present & accounts for 10 percent of global road accidents with more than 1.46 lakh fatalities annually.
Rolling resistance refers to the various forms of resistance against driving force when the vehicle is in motion. Several factors contribute to rolling resistance, including wind drag on the car, acceleration resistance generated by inertia force when speeding up, and resistance on the tyres. Tyre inflation pressure plays vital role on Coefficient of Rolling Resistance (RRC) of Tyre consequently vehicle mileage. Low or High tyre pressure is not good for driving comfort, safety of vehicle well as for environment. Petroleum Conservation Research Association ( PCRA ) has taken good initiative in direction to Tyre Star marking based on RRC values of Tyre.
Ride Comfort forms a central design aspect for suspension and is to be considered as primary requirement for vehicle performance in terms of drivability and uptime of passenger. Maintaining a balance between ride comfort and handling poses a major challenge to finalize the suspension specifications. The objective of this project it to perform ride- comfort analysis for heavy commercial truck using MATLAB Simulink. First, bench-marking was carried out on a 4x2 heavy commercial truck and the physical parameters were obtained. Further, a mathematical model is developed using MATLAB Simulink R2015a and acceleration- time data is collected. An experimentation was carried out on the truck at speeds of 20 kmph, 30 kmph, 40 kmph and 50 kmph over a single hump to obtain actual acceleration time domain data. This is followed by running the vehicle on Class A, B & C road profiles-irrespective of vehicle speed- to account for random vibrations.
Background: Due to Environmental concern worldwide, Mobility is under pressure to shift gear from fossil fuel to Electric. This is Rebirth of Electric Mobility is with state’s initiative, but it is facing bigger challenges than the 1900s era. Fossil fuel vehicles have already carved the benchmark on ease of range per charge, and time of charge (filling of fossil fuel), which needs to be at least matched by Electric Vehicles. The success of electric vehicles will not only be driven by state policy but also by performance and Economic Viability. While at this introduction level state is trying best to offset cost by way of subsidy/tax-sops offering. So, in clear terms “Performance of Electric Vehicles” need to be addressed and enhanced to put them in main stream in place of fossil fuel vehicles. In last 100 years there has been significant technological development in Motors, and Energy Storage, which is base of Electric mobility.
To control air pollution in urban areas and to reduce carbon print in the cities, nowadays EV’s are preferred over IC engine vehicles. Earlier Electric vehicles used DC motor and Induction motors. But Brushless Permanent Magnet motors are preferred over Induction motor for EV’s due to their High Torque density, high-power density and highly efficiency. Prevalent Electric vehicles today have Brushless DC motors. Compared to BLDC, PMSM motor have smoother control and negligible torque ripplesThus, PMSM motor is preferred over BLDC for Electric Vehicle, because of its sinusoidal back emf which results in smoother control, and results into smoother and more comfortable driving experience to users. Methodology Sensor based field-oriented control (FOC) is implemented in 48 V 5kW Interior PMSM motor. . To start the Synchronous motor initial position of the rotor magnetic field should be known.
OBJECTIVE Race vehicles are designed to achieve higher lateral acceleration arising at cornering conditions. A focused study on the steady state handling of the car is essential for the analysis of such conditions. The transient response analysis of the car is also equally important to achieve best driver-car relationship and to quantify handling in the range suitable for a racing car. This research aims to investigate the design parameters responsible for the transient characteristics and optimize those design parameters. This research work examines the time-based analysis of the problem to truly capture the non-linear dynamics. Apart from tires, chassis can be tuned to optimize vehicle handling and hence the response times. METHODOLOGY To start with, the system is modelled with governing parameters and simulation is carried out to set baseline configurations. Steady state and transient handling simulations run independent of each other with independent logic, coded on MATLAB.
Research Objective The importance of evaluating ride comfort with high degrees of accuracy objectively and its correlation with subjective perception is increasing day by day because of the long duration of the driving experience. The complex motion of the vehicle which is the combination of heave, roll and pitch motion is responsible for causing extreme uneasiness to the driver as well as the passenger. In this paper, ride comfort evaluation is done on the highway with similar traffic conditions with the help of Vibration Dose Value Analysis, Suspension Working Space and Ride Diagram methods for two hatchbacks and its correlation with the complex motion like choppiness of the vehicle is established that will help us to enhance the driver ride experience. Methodology The ride testing is performed for two hatchbacks on a highway road with different kinds of terrain ranging from highly uneven road roughness to moderately smooth surface for a speed range of 60-100 kmph.
Tyre Traction Trailer is a device designed to find the Peak Brake co-efficient of C2 and C3 tyre as per ECE R117. The trailer is towed by the truck and is braked suddenly to evaluate braking co-efficient of specimen tyre. It is a single wheel trailer equipped with load cell to capture tire loads (Normal and longitudinal)while braking. Traction Trailer is modelled in MSC Adams and rigid body simulation is carried out for static stability of the system. Dynamic simulations were performed to understand locking of wheels during braking. Body frame was further modelled as flex body to perform structural analysis of the frame. The paper contains stress and deformation plots of trailer Structure under various loading conditions, change in Centre of gravity, weight transfer and forces on springs during braking and cornering, plots of tractive and normal load on tyre during braking.
Increased public pressure to improve commercial truck safety and new stopping distance regulations have intensified the need to better understand the factors influencing heavy vehicle braking performance. To assist individuals and their organizations in preparing for these new truck braking standards, this seminar focuses attendees on understanding medium-duty hydraulic brake systems and heavy-duty air brake systems and how both systems' performance can be predicted, maintained and optimized.
Vehicle automation and intelligent transportation systems will be the cornerstones of sustainable smart cities of the future. People movers seem to be at the heart of technology development, field trials and on-road testing, and strategic business partnerships when it comes to connectivity and automated driving. Majority of the focus has been on unmanned operation and door-to-door service in urban environments and not on highways. Highways are relatively simpler to handle from an engineering stand-point, but vehicles typically operate at higher speeds, so the cost of accidents is worse.
The inovative approach to the assessment of directional stability of two-axle wheeled tractors during braking is considered. Assessment of the feasibility to in-stall brake mechanisms only on one axle of the tractor are considered. The equations to determine rational choice of braking force distribution between the axles for two-axle wheeled tractor are obtained. The coefficients of braking forces distribution between the axles of two-axles wheeled tractors of classical construction are obtained. The influence of the braking forces distribution between the axles on stability of wheeled tractors are determined. It was determined that operation of the brake systems of wheeled tractors has a significant impact on their directional stability, which is also manifested by the lack of a tendency to skid during braking. There is proposed improved method for evaluating the impacts of braking system on wheeled tractors stability by using the method of partial accelerations.
The brake pedal is the brake system component that the driver fundamentally has contact and through its action wait the response of whole system. Each OEM define during vehicle conceptualization the behavior of brake pedal that characterizes the pedal feel that in general reflects not only the characteristic from that vehicle but also from the entire brand. Technically the term known as Pedal Feel means the relation between the force applied on the pedal, the pedal travel and the deceleration achieved by the vehicle. Such relation curves are also analyzed in conjunction with objective analysis sheets where the vehicle brake behavior is analyzed in test track considering different deceleration conditions, force and pedal travel. On technical literature is possible to find some data and studies considering the hydraulic brakes behavior.
Analysis of road accident has showed that an important portion of fatal crashes involving commercial vehicles is caused by rollovers. ESC systems in commercial vehicles can reduce rollovers, severe understeer or oversteer conditions and minimize occurences of jackknifing conditions. Several studies have estimated that this positive effect of ESC on road safety is substantial. In Europe, Electronic Stability Control (ESC) is expected to prevent by far the most fatalities and injuries: about 3,000 fatalities (-14%), and about 50,000 injuries (-6%) per year. In Europe, Electronic Stability Control Systems is mandatory for all vehicles (since Nov 1st, 2011 for new types of vehicle and Nov 1st 2014 for all new vehicles), including commercial vehicles, trucks and trailers.
Heavy truck brake blocks are found to swell (or expand) permanently during testing or usage, especially so at high temperatures, thus leading to longer durability as measured by thickness loss, similar to light vehicle disc pads. This swelling phenomenon occurs continuously in the layer adjacent to the friction surface during testing or usage; not a one time event. The thickness loss estimated from the weight loss is always greater than measured thickness loss. Brake block wear does not increase linearly with increasing normal load, and the load-sensitivity of block wear is very much dependent on the products. A new test procedure has been developed for generating friction-vs.-temperature and wear-vs.-temperature data at a constant temperature employing intermittent braking on the Chase Brake Lining Quality Tester (SAE J661) and friction material wear can be compared on equivalent-work basis.
When driving in mountainous areas, vehicles often encounter downhill conditions. To ensure safe driving, it is necessary to control the speed of vehicles. For internal combustion engine vehicles, auxiliary brake such as engine brake can be used to alleviate the thermal load caused by the continuous braking of the friction brake. For battery electric vehicles (BEVs), regenerative braking can be used as auxiliary braking to improve brake safety. And through regenerative braking, energy can be partly converted into electrical energy and stored in accumulators (such as power batteries and supercapacitors), thus extending the mileage. However, the driver's line of sight in the mountains is limited, resulting in a certain degree of blindness in driving, so it is impossible to fully guarantee the safety and energy saving of downhill driving.
A method of vehicle straight angle motion relative its axial axis by turning the front wheels and simultaneous braking of the external side wheels is offered. The equation describing the condition of four-wheel drive vehicle crab motion is obtained. The purpose of the research is to determine the law of control of torque on the wheels of the car, the realization of which makes crab motion possible. For realization of the aim, the following challenges were solved: the torque difference on the driving wheels (the braking torque on the outside wheel) that provides “crab motion" is determined; an analysis of the operational factors influences and design parameters of the vehicle, on the magnitude of the required torque difference, was conducted.