Small Car Research Articles

Electric Cars in Brazil: An Analysis of Core Green Technologies and the Transition Process

This paper explores the transition to electric cars in Brazil. The country has been successful to reduce its carbon footprint using biofuels, but it is facing a dilemma in vehicle electrification. It cannot shift abruptly to battery electric vehicles, as current consumers are unable to afford them and investment in recharging infrastructure is uncertain. However, it has a significant manufacturing base, and it cannot isolate itself from global industrial trends. This study relies on the inductive case study method, identifying the core green technologies in vehicle electrification and extrapolating their trends, to explain how the transition process is feasible. The emergence of a dominant design (set of core technologies defining a product category and adopted by the majority of players in the market) in small and affordable segments is essential for the diffusion of electric cars in developing countries. Biofuel hybrid technologies may support the transition. The Brazilian industry can engage in electric vehicle development by designing small cars based on global architectures, targeting consumers in emerging markets. The article contributes by using a dominant design core technologies framework to explain and map the transition to electric vehicles in developing countries, supporting academic research, government, and industry planning.

Design of high-tension elastic cable barriers preventing rollover and climbing-over of various vehicles with high impact severity

A design procedure was presented for long-span semi-rigid cable barriers with strong posts that can prevent the rollover and climbing-over of various vehicles impacting with high impact severity while providing good occupant safety against high-speed small car crashes. The effective height of the barrier to prevent the climbing-over of buses was greater, regardless of a post spacing, than to prevent the rollover of pickup trucks. The effective height of the barrier increased as the post spacing decreased. The effective height of the cable barrier, required to prevent the rollover of pickup trucks colliding at 160 km/h speed (impact energy of 262 kJ) 60% larger than the commonly used impact speed of pickup trucks, was 0.65 m, similar to that of conventional rail-type barriers. A semi-rigid cable barrier for a 287 kJ (13-ton bus − 70 km/h − 20°) impact severity could provide THIV approximately 23% below the THIV threshold for a small car impact velocity of 160 km/h, 60% larger than the maximum impact speed typically applied to rail-type barriers. It could also limit the damage of cars and barriers due to small car and large vehicle impacts to a smaller section as compared to existing semi-rigid rail type barriers.

Impact of ethanol-gasoline implementation on vehicle emission based on remote sensing test

The vehicle exhaust remote sensing system was used to quantify the carbon monoxide (CO), hydrocarbon (HC), and nitrogen oxide (NO) concentrations of vehicles before and after the ethanol-gasoline implementation. The purpose was to investigate gasoline vehicle emissions for two distinct periods: before and after the ethanol-gasoline implementation. A comprehensive vehicle emission remote sensing data set collected in 2018 and 2019. The remote sensing test data was screened for duplicate vehicles in both two years. The average emission concentration of HC-CO-NO showed a continuous downward trend after ethanol-gasoline implementation. The three pollutant emission factors of small passenger cars are all lower than those of light trucks. Overall, the HC-CO-NO emission factors obtained through remote sensing tests have a small range of variation. From the results of the two-year test data, the emission levels of the 10% worst emission vehicles have shown a certain reduction compared with before the ethanol-gasoline implementation. Compared with random test errors of dynamometer emission test and portable emission measurement system, statistical results based on remote sensing test big data are more accurate.

An empirical analysis of electric vehicle cost trends: A case study in Germany

This study conducts a learning rate analysis on electric vehicle retail prices in Germany between 2015 and 2020 to predict the point of purchase price parity between electric cars and comparable conventional vehicles in different market segments. In small cars, a learning rate of 23% was found. For mid-sized cars, the rate of cost decline was 29%. A learning rate of 24% was observed in the luxury segment. Based on these results, it was found that luxury BEVs would reach price parity by the year 2023, and that midsized vehicle would follow by 2026. For small cars, the results indicate that price parity will not be achieved before the year 2030. The price parity results are complemented with an evaluation of the present and future total cost of ownership of electric and conventional cars. The analysis found that in 2020, mid-size and large electric vehicles were already close to price parity with conventional cars, even before subsidies provided by the German government. Small electric cars still required significant subsidies to be cost-competitive, however. The sensitivity of the analysis results to certain key parameters was evaluated, including the standard error of the learning rates, expected global BEV production in future years, the cost of conventional powertrains, and the effect of government subsidies on the ownership cost, and the duration of the vehicle ownership period. Overall, the results suggest that while the cost gap in larger cars will be closed around the middle of the decade, a higher rate of technological innovation is needed to make small BEVs cost-competitive with gasoline cars before the year 2030.

FACTORS AFFECTING STOPPING BEHAVIOUR AT SUBURBAN INTERSECTIONS

This study focused on how drivers dealt with intersections controlled by a stop sign at suburban in Al-Husn city at Irbid governorate, Jordan. The videotape was used at eight unsignalized intersections for one complete peak hour on weekdays. Any at-grade intersection that is not controlled by a traffic signal is defined as an "unsignalized intersection." The results showed that 48% out of 1,208 drivers took the decision to stop completely compared to 52% who chose to keep driving. Female drivers (75%) were observed to stop at intersections more frequently than male drivers. In terms of vehicle type, drivers of buses stopped more frequently than drivers of small passenger cars, which are road car, other than a motorcycle, that is designed to transport passengers. Driver age and compliance to a stop sign were found to be directly proportional to each other, but as the number of passengers in the vehicle increased, the rate of non-compliance also increased. Compliance was highest among leading vehicles, followed by following vehicles, and lowest among single vehicles. A binary logistic model showed that age, vehicle occupancy, and arrival pattern significantly affected stopping the behaviour. Gender and vehicle type were not significantly related to stopping the behaviour.

Development of a Test Level 3 Approach Guardrail Transition to Steel Tube Bridge Rail

A Manual for Assessing Safety Hardware (MASH) Test Level 3 (TL-3) approach guardrail transition (AGT) was designed to connect the Midwest Guardrail System to a MASH TL-4 steel tube bridge rail, designated Steel Railing, Type IL-OH. The AGT connection consisted of a 34 in. tall thrie-beam AGT, HSS8 × 6 × ¼ transition tube rails that aligned with the lower and middle bridge rail tubes, and new connection hardware designed to prevent vehicle snag during impacts. The new AGT connection was evaluated using a combination of LS-DYNA finite element analysis software and full-scale crash testing in accordance with MASH TL-3 impact criteria. The critical impact points were selected using LS-DYNA for MASH test nos. 3-20 and 3-21. In test SBRTR-1, a 2,404 lb small car struck the AGT at a speed of 64.6 mph, an angle of 25.2°, and at a location 21.3 in. upstream from the last transition post. In test SBRTR-2, a 5,007 lb quad cab pickup truck struck the AGT at a speed of 62.7 mph, an angle of 24.9°, and at a location 15.9 in. upstream from the last transition post. The small car and pickup truck were both contained and redirected and the tests resulted in a successful evaluation according to MASH TL-3 safety performance criteria. Implementation guidance for the new AGT in various configurations is provided.

Evaluation and Optimization of the Aerodynamic Noise Reduction of Vehicle Side View Mirrors: Experimental and Numerical Study

Automobile passengers are usually sensitive to the noises generated by the engine and vehicle body. One of the noise sources is the generated turbulent flow around the Vehicle Side View Mirror (VSVM) and around the A-pillar, producing fluctuating pressure. Unwanted noise is a result of fluctuating pressure around the car's body. Modification of the geometry of the vehicle body may affect the generated noise by turbulent flow. In this paper, the original side view mirror of a small sedan car named Tiba was aimed at geometry modification to decrease airborne noise. The mirror was assessed by CFD simulation and an outdoor test. Road tests were applied at three forward speeds (80, 100, and 120 km/h) to measure the sound level generated by the vehicle's side mirrors. Then, the geometry of VSVM was modified to diminish the sound pressure level of that based on decreasing turbulent flow and fluctuating pressure around the side mirror. Finally, the achieved geometry was evaluated using road tests, which showed a noise reduction of 8 to 12%. Road tests were done for the modified side car mirror. It shows that a modified mirror can reduce the sound level of airborne noise. By using this suggested modified side view mirror, the risk of annoying noise may be diminished and passenger comfort ability can be increased through driving. Doi: 10.28991/HIJ-2022-03-01-08 Full Text: PDF

CES 2022: Less is More

AbstractScaled‐down show still delivers top‐notch exhibits and innovation aplenty.

An Empirical Study on Customers’ Preference of Cars with Special Reference to Maruti Suzuki and Tata Motors

In present day world cars have no longer remained a luxury item, especially small cars. Moreover, there has been an ambition among the people to own a car, more so during Covid times. The desire of the people has also been complimented by introduction of new models and offers by car manufacturers as well as easy source of finance at competitive rates. This study is undertaken to assess the factors considered by car buyers while selecting a car and their satisfaction level. For this study two manufacturers were selected- Maruti Suzuki the market leader and a strong Indian competitor Tata Motors. The study revealed that though Maruti Suzuki still has the highest customer base due to its brand image, Tata Motors is gaining new customers by providing strong and sleek cars.

Investigation of Gear Ratios for Hybrid System in Small Race Car Using Lap Time Simulation

To improve the dynamic performance of small racing hybrid vehicles which use an electric motor and engine, we proposed a hybrid system to synchronize these torques with simple composition. In this paper, the motor gear ratio and final gear ratio for optimizing the vehicle performance of a hybrid system in a small race car are investigated using lap time simulation. Specifically, we compared lap times on the evaluation circuit, a 400 m straight line, using the calculation method of a quasi-steady lap time simulation with a simplified vehicle model. In the paper, the hybrid system for a small race car is described, then the calculation method of the quasi-steady state lap time simulation is presented and the simulation results are discussed.

Housing Issue and Attempts to Solve it During the “Khrushchev Thaw”: a View From the Province (on the Example of the Mordovian ASSR)

Introduction. The relevance of the work is due to the demand for Soviet experience in implementing large-scale state projects, in particular in the field of housing construction, at the present stage of Russian modernization. Methods. The factual material available in the work is drawn from the funds of the Central State Archive of the Republic of Mordovia, as well as from published sources. During the research, the following methods were used: comparative-historical, problem-chronological, historical-cultural, historical reconstruction. Results. The dynamics of all types of housing construction in the republic during the study period received the maximum turnover. Discussion. One of the reasons for significant success in the field of housing construction in the republic was the reform of the country’s economic system. Sovnarkhoz turned out to be more flexible and adapted to the conditions of planned administering as management structures, which in particular manifested itself in the field of housing construction. Other reasons for success were a kind of “revolution” in the development of housing construction methods, when, along with the state, the “people’s construction” and the cooperative method began to be widely used, as well as the industrial basis of construction, albeit not always consistently implemented. At the same time, the speed of construction generated a lot of problems in hastily constructed standard small cars, which became the reverse side of Khrushchev’s housing policy. Conclusion. The housing policy pursued by the Khrushchev leadership was one of the indisputable social conquests of the time under study, when a significant part of people from barracks and communal apartments moved to separate apartments intended for settlement by one family. However, when solving this most important problem, the authorities placed special emphasis not so much on the development of new construction technologies, as on managerial reorganization, leading ultimately to a simple increase in the workforce and organizations involved in the construction of residential facilities.

Manufacturing A Personalised Composite Material Driver’s Seat

The paper presents the process of 3D-printing and laminating a composite material driver’s seat for Silesian Greenpower’s electric vehicle. Silesian Greenpower is a student’s interfaculty project, of which aim is to design, build and race a small electric race car. Aerodynamics and lightweight construction play a major role, so each element applied in the car is optimized and customized to fit in the vehicle. For this purpose, 3D-printing technology is often used by the team. A seat model made on the basis of the driver's anthropometric model was presented in the paper. Subsequently, after the appropriate adaptation of the obtained surfaces to interconnect them with each other, the FDM technology was applied using PET-G material. To increase the strength of the connections of the printed elements and to strengthen the design and stability of the chair, the element was laminated using carbon fibre and epoxy resin. The lamination process is presented and discussed in the article.

Operation principles for hydrogen spark ignited direct injection engines for passenger car applications

The sustainable reduction of greenhouse gas emissions from road transport requires solutions to achieve net-zero carbon dioxide emissions. Therefore, in addition to vehicles with electrified powertrains, such as those implemented in battery electric of fuel cell vehicles, internal combustion engines fueled with e-fuels or biofuels are also under discussion. An e-fuel that has come into focus recently, is hydrogen due to its potential to achieve zero tank-to-wheel and well-to-wheel carbon dioxide emissions when the electrolysis is powered by electricity from renewable sources. Due to the high laminar burning velocity, hydrogen has the potential for engine operation with high cylinder charge dilution by e.g. external exhaust gas recirculation or enleanment, resulting in increased efficiency. On the other hand, the high burning velocity and high adiabatic flame temperatures pose a challenge for engine cooling due to increased heat losses compared to conventional fuels. To further evaluate the use of hydrogen for small passenger car engines, a series production 1 L 3 cylinder gasoline engine provided by Ford Werke GmbH was modified for hydrogen direct injection. The engine was equipped with a high pressure external exhaust gas recirculation system to investigate charge dilution at stoichiometric operation. Due to limitations of the turbocharging system, very lean operation, which can achieve nitrogen oxides raw emissions below 10 ppm, was limited to part load operation below BMEP = 8 bar. Thus, a reduction of the nitrogen oxides emission level at high loads compared to stoichiometric operation was not possible. At stoichiometric operation with external exhaust gas recirculation engine efficiency can be increased significantly. The comparison of stoichiometric hydrogen and gasoline operation shows a reduced indicated efficiency with hydrogen with significant faster combustion of hydrogen at comparable centers of combustion. However, higher boost pressures would allow to achieve even higher indicated efficiencies by charge dilution compared to gasoline engine operation.

Standortoptimierung ÖBB Kraftwerk Spullersee – Bauen zwischen Naturjuwel und alpinen Extremen

AbstractThe construction site is located close to the Spullersee, one of the most impressive mountainsides in the Alps, and is part of the ÖBB Spullersee power station, which is used to generate green 16.7 Hz traction current. The Spullersee, a formerly natural mountain lake, is located over 1800 m a.s.l.in the municipality of Dalaas in Vorarlberg. After almost a century of generating electricity, essential parts of the plant have reached the end of service life, resulted in essential facility renewals as well as numerous operational optimizations in the last two years. In a first construction phase, a new access tunnel to the existing apparatus chamber had to be excavated before seasonal winter closure of the access road. For the winter construction phase, thousands of tons of building materials were stored on the construction site in order to replace the old system parts in the area of the lake‐side apparatus chamber after the Spullersee had been completely emptied. Due to high‐alpine location of the site in one of the snowiest regions in Austria, not just working in winter was challenging, but also access. In winter the site was achieved only by using a small cable car and a narrow footpath through the almost two‐kilometer‐long pipe tunnel. This was not everyone's cup of tea.

ECAP-YOLO: Efficient Channel Attention Pyramid YOLO for Small Object Detection in Aerial Image

Detection of small targets in aerial images is still a difficult problem due to the low resolution and background-like targets. With the recent development of object detection technology, efficient and high-performance detector techniques have been developed. Among them, the YOLO series is a representative method of object detection that is light and has good performance. In this paper, we propose a method to improve the performance of small target detection in aerial images by modifying YOLOv5. The backbone is was modified by applying the first efficient channel attention module, and the channel attention pyramid method was proposed. We propose an efficient channel attention pyramid YOLO (ECAP-YOLO). Second, in order to optimize the detection of small objects, we eliminated the module for detecting large objects and added a detect layer to find smaller objects, reducing the computing power used for detecting small targets and improving the detection rate. Finally, we use transposed convolution instead of upsampling. Comparing the method proposed in this paper to the original YOLOv5, the performance improvement for the mAP was 6.9% when using the VEDAI dataset, 5.4% when detecting small cars in the xView dataset, 2.7% when detecting small vehicle and small ship classes from the DOTA dataset, and approximately 2.4% when finding small cars in the Arirang dataset.

Performance Analysis of a Main Drive Motor—Initial Study of an EV Modeling Software Design

This study aimed to determine and analyze the performance of an electric motor installed in a small city car, which was an internal combustion engine (ICE) car with manual transmission and front-wheel drive converted into an electric vehicle. A manual transmission vehicle was used, considering its type is the cheapest. This was to push aside the perception that electric cars are not accessible to the lower classes. Another technical matter was the focus on the power and torque performance of the electric motor and the transmission. A 7.5 KW three-phase induction motor was installed and assembled with 200 AH 76.8 VDC batteries. Electronic power steering (EPS) and the air conditioner (AC) were not operated, while power for the electrical accessories and power analyzer was obtained from a separate 12 VDC battery. Vehicle analysis focused on the power consumption, which was measured and acquired using a power analyzer. The vehicle was driven in real terms with three passengers. GPS was also used to determine the vehicle position and collect elevation data during testing. The derivatives of the GPS data were the speed, acceleration, and distance traveled by the vehicle. The initial hypothesis was that the car could cover a distance of 30 km with regular usage.

Experimental Study on The Influence of Precision Instruments Caused by Heavy Vehicles Vibration

In order to evaluate the influence of heavy vehicles vibration on precision instruments in a proposed experimental building, the three-dimensional environmental vibration induced by heavy vehicles was measured in a soft soil site. Combined with continuous wavelet transform and 1/3 octave frequency vibration level, the vibration transferring characteristics of the construction site were analyzed, and the Z vibration level of the site was tested. The results are as follows: (1) Vertical vibration is the main vibration; (2) The predominant frequency of soil layer is 4 Hz, and the excitation frequency of vehicles is 5 ~ 20 Hz; (3) With the increase of vibration source distance, the high frequency vibration is greatly attenuated, while the low frequency vibration is amplified; (4) The amplitude of heavy vehicles is about 3 ~ 5 times of the small cars; (5) The environmental vibration produced by the vehicles exceeds the vibration standard of the normal use of the instruments, necessary vibration reduction and isolation measures should be taken.

Analysis of Pedestrian Fractures in Collisions Between Small Cars and Pedestrians Based on Surveillance Videos.

To discuss the collision relationship and the cause of the fracture caused by traffic accidents in which the front of a small car collides with the side of a pedestrian while braking. The surveillance videos of 42 traffic accidents involving the front of a small car colliding with the side of a pedestrian while braking were collected. By analyzing the surveillance videos and the paths, the speed of the collision, the relationship between the vehicle and the pedestrian upon collision, and the movement trajectory of the human body were clearly identified. The type and severity of the injuries were also determined through autopsy. The characteristics of the human injuries and vehicle paths were analyzed according to the collision speed (<40 km/h, 40-60 km/h, 60-90 km/h), and the correlations between the fracture and the height of the pedestrian, the height of the hood and the length of the hood were discussed. When a small car hits the side of a pedestrian, the front bumper first hits the lower limbs of the pedestrian, and then, the human body falls to the side of the vehicle, causing a secondary collision with the hood and front windshield; thus, the pedestrian is thrown at a speed similar to the speed of the vehicle, finally falling to the ground and sliding forward a certain distance. (1) When V is less than 40 km/h (n = 10), the pedestrian's head did not collide with the windshield, and the fatal injuries were caused by the individual striking the ground. (2) When V is greater than 40 km/h (n = 32), the majority (97%) of cases showed collision with the windshield. (3) When 40 to 60 km/h (n = 16), the pedestrian's head collided with the windshield, which can cause fatal injuries, and pelvic fractures and rib fractures occurred in 56.25% of patients. (4) When V is less than 60 km/h (n = 26), the ratio of the height of the pedestrian to the height of the hood was significantly smaller in the pelvic fracture group than in the nonpelvic fracture group (P < 0.01). (5) When 60 to 90 km/h (n = 16), there were holes in the windshield, and the pedestrians experienced severe head injuries, with cervical spine fracture occurring in 37.5% of patients, pelvic fractures occurring in 43.75% of patients, and rib fractures occurring in 31.25% of patients. When V is less than 40 km/h, the vehicle does not cause severe injuries in pedestrians; when V is greater than 40 km/h, the collisions of the pedestrian's head with the windshield lead to severe head injuries and the accident can cause severe pelvic and rib fractures; when V is greater than 60 km/h, the collisions of the pedestrian's head with the windshield can cause cervical spine fracture in addition to head injuries. The occurrence of human injuries is related to not only the vehicle speed but also factors such as the height of the pedestrian, the height of the hood and the length of the hood.

Embedded YOLO: A Real-Time Object Detector for Small Intelligent Trajectory Cars

YOLO-Tiny is a lightweight version of the object detection model based on the original “You only look once” (YOLO) model for simplifying network structure and reducing parameters, which makes it suitable for real-time applications. Although the YOLO-Tiny series, which includes YOLOv3-Tiny and YOLOv4-Tiny, can achieve real-time performance on a powerful GPU, it remains challenging to leverage this approach for real-time object detection on embedded computing devices, such as those in small intelligent trajectory cars. To obtain real-time and high-accuracy performance on these embedded devices, a novel object detection lightweight network called embedded YOLO is proposed in this paper. First, a new backbone network structure, ASU-SPP network, is proposed to enhance the effectiveness of low-level features. Then, we designed a simplified version of the neck network module PANet-Tiny that reduces computation complexity. Finally, in the detection head module, we use depthwise separable convolution to reduce the number of convolution stacks. In addition, the number of channels is reduced to 96 dimensions so that the module can attain the parallel acceleration of most inference frameworks. With its lightweight design, the proposed embedded YOLO model has only 3.53M parameters, and the average processing time can reach 155.1 frames per second, as verified by Baidu smart car target detection. At the same time, compared with YOLOv3-Tiny and YOLOv4-Tiny, the detection accuracy is 6% higher.

Mahindra Electric Cars: Challenges of Driving a Revolution in the Indian Market

Small cars accounted for 75% of the cars sold in India; electrification of these cars and making them affordable was one of the major challenges apart from the infrastructure. Hence, leading automakers saw this as highly impracticable. However, Mahindra Electric Cars Pvt. Ltd., India’s only electric car maker, firmly believed that electric mobility, though in the nascent stage, is the future of the automotive sector. The case tries to deals with Mahindra Electric Cars Pvt. Ltd.’s opportunities and challenges, the pioneers in electric mobility in India in the wake of government decision. It raises certain imperative questions like: Is the Indian market ready for electric cars? What will be the likely impact on the current market scenario? Can the automaker create a favourable perception in consumers’ minds towards electric cars? Will this new category thrive in a hyper-competitive conventional market? This case is written based on insights provided by the company. The case authors interacted with the four-member Mahindra team in Bangalore, India, and got first-hand input.