Full-size Car Research Articles

Aerodynamic Influence of Deformations due to Wind Load on Full-Sized Passenger Cars

Aerodynamic Influence of Deformations due to Wind Load on Full-Sized Passenger Cars

Optimal Measures for Smoke Control Performance for an Underground Parking Lot

The urban environment has been changing rapidly, and with buildings becoming larger, denser, and more complicated, parking lots have gradually been moved underground. The consumption pattern of vehicles has changed from compact to mid- or full-sized cars, and the risk of car fires has also increased with the use of more flammable materials in cars to improve fuel efficiency. Consequently, the necessity of smoke control applications in underground parking lots has become essential to ensure fire safety. Smoke control partition areas were set to 5000 m<sup>2</sup>, 3000 m<sup>2</sup>, and 2000 m<sup>2</sup>, to analyze the performance of smoke control facilities in underground parking lots. The flow rate of smoke control was set to 18 CMH and 27 CMH and compared with the duct installation setup. The results showed that smoke control performance was most suitable when the smoke control partition area was set to 3000 m<sup>2</sup>, the flow rate of the smoke control was 27 CMH, and the duct was installed.

Using Web Crawling and Word Cloud Methods to Investigate Issues Arising from Expanded Implementation of Vehicle and Garage Joint Registration Policy

제주특별자치도는 2007년 전국에서 최초로 차고지증명제를 도입하여 시행하고있다. 2017년 1월부터 적용 대상이 대형차량에서 중형차량까지 확대 되었고, 2019년 7월부터 적용 지역이 제주시 동지역에서 제주 전 지역으로 확대되었다. 본 논문은 차고지증명제 전 지역 확대 시행과 관련한 우려를 언론기사와 댓글을 중심으로 살펴보고자 한다. 이를 위해 웹 크롤링 기법을 적용하여 차고지증명제와 관련이 있는 언론기사 및 댓글을 추출하고, 언급된 단어를 워드 클라우드를 통해 시각적, 정량적으로 분석하였다. 언론기사 분석결과 ‘차량’, ‘주차장’, ‘확대’ 등 차고지증명제 확대 시행에 대한 정보 전달과 관련한 단어들이 언급됨에 반해, 댓글에서는 ‘차고지’, ‘주차장’이 ‘불편’ 등 주차공간 부족에 대한 우려와 같은 부정적인 반응, ‘장애인’, ‘버스’, ‘단속’ 등 제도의 사각지대 혹은 보완방안과 관련한 단어들이 많이 언급되었다. 이와 같은 우려 사항과 보완방안들은 차고지증명제의 정책 수용성을 확대하고 2022년 예정된 차고지증명제 전 차종 전면시행을 선제적으로 준비하기 위해 적극적 활용할 필요가 있다.In 2007, Jeju Special Self-governing Province implemented vehicle and garage joint registration policy (levying garage option on car buyers or garage identification system), requiring a garage or parking space to register for auto ownership. This policy has been applied to a full-size car, while it has expanded to a mid-size car since 2017. Recently, the entire localities became target areas for this policy while only urbanized area of Jeju-city has been in effective over the past 12 years. Due to the early geographic expansion, which is originally scheduled to year 2022, various issues and concerns arise. This paper investigates issues on expansion of the vehicle and garage joint registration policy, using Web Crawling and Word Cloud methods. Web Crawling archives online news and its comments relevant to the vehicle and garage joint registration policy while Word Cloud visualizes keywords frequently presented in the news and comments. Results show that a group of words found in online news, such as ‘Vehicle’, ‘acquisition’, ‘garage’, ‘expansion’, providing information about expansion of vehicle and garage joint registration policy. On the other hand, in comments, concerns on insufficient number of garage or parking space, negative responses (‘problem’, inconvenience’, etc.), and finally, mid-term and/or long-term improvement (‘handicapped person’, rental car’, ‘public transportation’, ‘enforcement’, etc.) are largely found. Implications on policy acceptance and improvement are discussed.

Experimental Verification of Inertial Navigation with MEMS for Forensic Investigation of Vehicle Collision

This paper studies whether low-grade inertial sensors can be adequate source of data for the accident characterization and the estimation of vehicle trajectory near crash. The paper presents outcomes of an experiment carried out in accredited safety performance assessment facility in which full-size passenger car was crashed and the recordings of different types of motion sensors were compared to investigate practical level of accuracy of consumer grade sensors versus reference equipment and cameras. Inertial navigation system was developed by combining motion sensors of different dynamic ranges to acquire and process vehicle crash data. Vehicle position was reconstructed in three-dimensional space using strap- down inertial mechanization. Difference between the com- puted trajectory and the ground-truth position acquired by cameras was on decimeter level within short time window of 750 ms. Experiment findings suggest that inertial sen- sors of this grade, despite significant stochastic variations and imperfections, can be valuable for estimation of veloc- ity vector change, crash severity, direction of impact force, and for estimation of vehicle trajectory in crash proximity.

Multifunctional structural energy storage composite supercapacitors.

This paper addresses the challenge of producing multifunctional composites that can simultaneously carry mechanical loads whilst storing (and delivering) electrical energy. The embodiment is a structural supercapacitor built around laminated structural carbon fibre (CF) fabrics. Each cell consists of two modified structural CF fabric electrodes, separated by a structural glass fibre fabric or polymer membrane, infused with a multifunctional polymeric electrolyte. Rather than using conventional activated carbon fibres, structural carbon fibres were treated to produce a mechanically robust, high surface area material, using a variety of methods, including direct etching, carbon nanotube sizing, and carbon nanotube in situ growth. One of the most promising approaches is to integrate a porous bicontinuous monolithic carbon aerogel (CAG) throughout the matrix. This nanostructured matrix both provides a dramatic increase in active surface area of the electrodes, and has the potential to address mechanical issues associated with matrix-dominated failures. The effect of the initial reaction mixture composition is assessed for both the CAG modified carbon fibre electrodes and resulting devices. A low temperature CAG modification of carbon fibres was evaluated using poly(3,4-ethylenedioxythiophene) (PEDOT) to enhance the electrochemical performance. For the multifunctional structural electrolyte, simple crosslinked gels have been replaced with bicontinuous structural epoxy-ionic liquid hybrids that offer a much better balance between the conflicting demands of rigidity and molecular motion. The formation of both aerogel precursors and the multifunctional electrolyte are described, including the influence of key components, and the defining characteristics of the products. Working structural supercapacitor composite prototypes have been produced and characterised electrochemically. The effect of introducing the necessary multifunctional resin on the mechanical properties has also been assessed. Larger scale demonstrators have been produced including a full size car boot/trunk lid.

Novel Crankshaft Mechanism and Regenerative Braking System to Improve the Fuel Economy of Light Duty Vehicles and Passenger Cars

Improvements of vehicle fuel economy may be achieved by the introduction of advanced internal combustion engines (ICE) improving the fuel conversion efficiency of the engine and of advanced power trains (PWT) reducing the amount of fuel energy needed to power the vehicle. The paper presents a novel design of a variable compression ratio advanced spark ignition engine that also permits an expansion ratio that may differ from the compression ratio hence generating an Atkinson cycle effect. The stroke ratio and the ratio of maximum to minimum in-cylinder volumes may change with load and speed to provide the best fuel conversion efficiency. The variable ratio of maximum to minimum in-cylinder volumes also improves the full load torque output of the engine. The paper also presents an evolved mechanical kinetic energy recovery system delivering better round trip efficiencies with a design tailored to store a smaller quantity of energy over a reduced time frame with a non-driveline configuration. Simulations show an improvement of full load torque output and fuel conversion efficiency. Brake specific fuel consumption maps are computed for a gasoline engine 2 liters, in-line four, turbocharged and directly fuel injected showings significant fuel savings during light and medium loads operation. Results of vehicle driving cycle simulations are presented for a full size car equipped with the 2 liters turbo GDI engine and a compact car with a downsized 1 liter turbo GDI engine. These results show dramatic improvements of fuel economies for similar to Diesel fuel energy usage and CO2 production. The turbo GDI engines with the alternative crank trains offer better than hybrids fuel economies if the vehicles are also equipped with the mechanical kinetic energy recovery system (KERS) recovering the braking energy to reduce the thermal energy supply in the following acceleration of a driving cycle.

Case—Bidding on Priceline

Bidding on Priceline A student wants to travel to New York. He has purchased his airline ticket and is starting to schedule his three-day trip. First, he thinks he should rent a car at the airport. His friends give him two suggestions: (1) go to www.priceline.com to “name his own price,” (2) go to a traditional car rental agency website such as www.hertz.com. Priceline.com is an Internet-based corporation offering serviced-based products such as airline tickets, hotel rooms, rental cars, and home mortgages. For its rental car services, Priceline provides a wide array of car types from categories such as economy, standard, and full-sized cars. Once you are on Priceline.com and have selected Rental Cars from the option button, the procedure for bidding on this site is as follows (Figure 1): 1. You choose the type of place where you want to rent a car, the pick-up city, and the pick-up and drop-off date and time. 2. You then enter the flight information, driver information, and (most importantly) name your own price for renting this particular type of car (Figure 2). 3. If you offer an extremely low price, Priceline will inform that your offer is not likely to be accepted by any agency and provide suggestions about how much to bid in order to get the car. You are allowed to bid only once for each type of car, which means you have to be careful about the amount of money you bid, potentially paying full rate if not successful (Figure 3). 4. Whether you follow this suggestion or not, Priceline will process your request as you go to the next step and let you enter personal identification and credit card information. 5. You will be notified if your offer is accepted within one hour. There are two possible results: either you can rent the car at the price you named or your offer is rejected and you cannot bid on this car class again for this particular arrival/drop-off combination. When the bidder offers a low bid Priceline will provide some insight into potentially more successful bids without offering specific information. For example, Figures 4 and 5 are Priceline suggestions offered after a user enters very low bids for standard and full-sized cars. An alternative option is to go to www.hertz.com to make a reservation for renting the car. Figure 6 is a price quote from Hertz.com offered on the same date as the bids on Priceline.com in Figures 4 and 5. Now there are two options for our would-be traveler—he can either bid on Priceline.com or make a reservation on Hertz.com. Given his student status, he wants to spend as little money as possible. Obviously, he should try Priceline.com first, since it gives him a chance (without any cost except time) of renting a car at a very low price. He is traveling alone with very little luggage so it won’t make much difference whether he chooses an economy, standard, or full-sized car. Since he gets only one chance to bid for each type of car, he needs to work out a solution so that he can take the maximum advantage of Priceline.com. As a final thought he wonders if he can extract any information from failed bids, i.e. if his first bid is unsuccessful, how should he alter his subsequent bids?

Robot rush hour

Describing DARPA's latest contest, the so-called urban challenge, is simple: drive a full-size car 60 miles in traffic, obey the rules of the road, complete mock urban supply missions and win big bucks from the US government. Robots faced several challenges while completing their missions, including overtaking other cars.

An offset rigid barrier-based test: equivalence to the Insurance Institute for Highway Safety frontal offset impact safety test

The current Insurance Institute for Highway Safety (IIHS) frontal offset impact safety assessment, which is similar to the European New Car Assessment Program (EuroNCAP), uses a fixed deformable barrier of aluminium honeycomb construction. The IIHS offset deformable barrier (ODB), designed to mimic an average collision partner during an accident, is however a relatively expensive and time-consuming representation for evaluating the safety of a given vehicle during frontal collisions. The repeatability of tests based on ODBs has also been questioned in some investigations reported in published literature. In the current paper, available finite element models of a compact car (Dodge Neon) and a full-size car (Dodge Intrepid) were first improved and validated against actual test results reported by the IIHS. Each of these validated models was next subjected to 40% offset impact against a rigid wall in lieu of the deformable IIHS barrier at a lower speed calculated on the basis of energy balance. The simulations were carried out with the aid of the explicit code LS-DYNA. It was shown that a remarkably good correlation can be obtained for occupant compartment intrusions for impact against an offset rigid barrier vis-à-vis the IIHS ODB. Thus, at a lower speed the offset rigid barrier can be a cost-effective and efficient alternative to the currently used ODB.

Firing on Half-Cylinders

This article reports on innovations in designing fuel-efficient eight-cylinder engines. Despite rising fuel prices and fears of an oil crunch, Americans' lust for big vehicles with gas-gulping V-8 engines is unlikely to abate anytime soon. So unless a full-size car or truck is passing at speed, climbing a hill or towing a trailer, its eight-cylinder engine runs only half-heartedly--and inefficiently: operating at less than full load lowers fuel economy. Power-train engineers at DaimlerChrysler and General Motors have perfected an affordable way to smoothly morph V-8 gas guzzlers into V-4 fuel misers and back again as required. To the automakers, the new cylinder-deactivation systems provide a relatively low cost way to improve the poor fuel mileage figures otherwise posted by their latest crop of five-liter-plus pushrod engines--Chrysler's popular Hemi and General Motors's new Gen IV small-block V-8. INSET: CUTTING THE FAT.

Development and validation of high fidelity vehicle crash simulation models

A program is underway to develop and validate a high fidelity finite element model of a full size car for crashworthiness analysis. This study is part of an overall program to develop a set of detailed finite element models for various vehicles that represent the range of vehicle types currently on the road. These vehicle models can then be used to study how future lightweight vehicles will change the overall crash safety of the fleet. The representative full-size car selected for this program was the Ford Crown Victoria. The model development required the teardown and digitisation of a vehicle to characterise the geometry and material testing to measure the mechanical properties. The digitised structural component surfaces were then used to generate the vehicle components in the finite element model. An important step in the overall model development is the validation of the model. Vehicle frontal and side impact tests had been performed on the Crown Victoria. Data from these full vehicle crash tests provided a primary set of measurements for validating the crash model. However, complete validation of the model based only on the existing vehicle crash tests is difficult because of the complexity of the crash responses and the limited number of measurements in the tests. Accurate simulation of the crash response requires modelling both the response of the individual structural components and the interaction between components to obtain the complete vehicle crash behaviour. To assist in the model validation some additional component tests were performed. The vehicle component tests included a front bumper rigid pole impact test, a front door rigid pole impact test, and a vehicle frame rigid wall impact test. The use of these component tests in model validation is shown to illustrate the approach.

Vibration Control of Super-High-Speed Elevators : Car Vibration Control Method Based on Computer Simulation and Experiment Using a Full-Size Car Model

A new vibration control mechanism and control method for suppressing horizontal vibration in super-high-speed elevator cars are considered here. The actuator consists of an AC servomotor and a ball screw, and the vibration of the cabin, detected by an acceleration sensor. The acceleration signal is integrated to determine the velocity and the position. The control force is determined based on the above position and velocity, and on the velocity of a motor encoder taking into account the car dynamics. First, the dynamics of an elevator car with the control are formulated, and the effect of the control on vibration suppression is evaluated by numerical simulation. The results indicate good performance of the vibration control system, which suppresses 1st- and 2nd-mode vibrations of the car. Furthermore, the control force and actuator stroke are within the practical range of designed values. Second, a vibration test equipment system using a full-size car is developed in order to test the performance of the vibration control system. Finally, using this system, it is experimentally confirmed that the vibration control mechanism reduces vibration to half that of a control-free car.

The Perception of Arrival Time for Different Oncoming Vehicles at an Intersection

We make an appeal to bring the theoretical tools of ecological psychology to focus on road-traffic accidents that result from making left turns. Following a review of previous arrival-time literature, we report an experiment that was conducted in a fixed-base driving simulator to determine the perceptual basis for judgments to turn left. We manipulated the arrival time (Ta) of an oncoming vehicle, the viewing distance to that vehicle, and the type of oncoming vehicle. Forty-eight participants were randomly assigned to a group in which a motorcycle, a compact car, a full-size car, or a delivery truck represented the oncoming vehicle. There were equal numbers of male and female participants in the four groups. As Ta, was increased, underestimation of vehicle Ta also increased. Significant main effects were found for Ta, gender of participants, vehicle type, and viewing distance; significant effects were also found for interactions for gender by Ta and gender by vehicle type. Men and women differed in their accuracy of judgments for vehicle types; men were more accurate in estimating the arrival of delivery vans and motorcycles than women. The accuracy of Ta estimation for the type of the approach vehicle and distance removed suggests that participants used vehicle-size information in their judgments. We present a discussion of a number of disappearancen methodological issues and research applications. Language: en

Perception of Oncoming Vehicle Time-to-Arrival

An experiment was conducted in a fixed-base driving simulator which manipulated the time-to-arrival (Ta) of an oncoming vehicle, the viewing distance to that vehicle and the type of oncoming vehicle to determine the perceptual basis for a left-turn decision. Forty-eight participants were randomly assigned to a group where either a motorcycle, a compact car, a full-size car, or delivery truck represented the oncoming vehicle. There were an equal number of participants of each gender in the four groups. As Ta was increased, underestimation of vehicle arrival time also increased. Significant main effects were found for Ta, gender of participants, vehicle type, and viewing distance, and for interactions for gender x Ta and gender x vehicle type. Males and females differed in their accuracy of judgments for vehicle types, where males were more accurate in estimating the arrival of delivery vans and motorcycles than their female peers. The pattern of results for the size of the approach vehicle were consistent with a margin-of-safety explanation which argues that driver underestimation of the arrival times of larger vehicles generally allows larger margins-of-safety than for smaller vehicles. The importance of these findings for the development of advanced in-vehicle collision avoidance and warning systems is briefly considered.

Wind tunnels for industrial aerodynamics

Different types of wind tunnels for industrial aerodynamics are described briefly. The influence parameters effecting the reliability of wind tunnel test results are discussed extensively. For wind tunnels used for building aerodynamic investigations in smooth flow the effect of blockage on the drag coefficient and the pressure distribution around simple bodies is discussed. For full size car aerodynamic wind tunnels results of comparison tests are reported and the physical reasons for the differences are discussed. Most of the differences seem to be due to the non-appropriate flow situation in the open test sections. Based on a new jet calculation method developed by Regenscheit an example of an intake calculation for an open jet is demonstrated. For wind tunnel diffusors some improvement is possible, if step diffusors and angular diffusors are combined.

The Effect of Small Cars on the Capacity of Signalized Urban Intersections

Time headways between vehicles being discharged from a queue at a signalized urban intersection is a measure of the intersection’s capacity. An event recorder actuated by tape switches on the road surface is used to measure headways at various signalized intersections in Toronto. The headways during saturation flow are related to the size of the vehicles and it is found that vehicles follow a small car with a closer headway than a full-sized car and a small car follows a vehicle closer than a full-sized car. The combined effect when both the lead and following vehicles are small cars is found to yield the smallest headways. This combined effect is most significant for the vehicles at the beginning of the queue. As a result, it is estimated that the capacity of a signalized intersection is increased by up to 15% for a stream of small cars over a stream of full-sized cars.

Accident involvement and crash injury rates: An investigation by make, model and year of car

Accident involvement and crash injury rates per million miles of vehicle travel are estimated by make, model and year of car. The accident and injury information was obtained from the North Carolina accident files, while exposure data were derived from paired odometer readings recorded on a statewide sample of motor vehicle inspection receipts. The resulting estimates show a steady decrease in annual mileage with vehicle age. For the newer model years, large cars have generally higher annual mileages than small cars, and station wagons higher mileages than sedans or hardtops. The accident involvement and injury rates decline for the newer model cars, especially for larger-sized cars. Full-sized cars have the lowest overall accident and injury rates. Among standard-sized cars, two-door cars have higher accident and injury rates than four-door cars, and hardtops higher than sedans or station wagons.

THE DRIVER'S REFERENCE POINT AS A FUNCTION OF VEHICLE TYPE, DIRECTION AND RADIUS OF TURN.

A study was conducted to determine the location of the point on the long axis of an automobile which intersects the center line of a prescribed path when driven under a variety of conditions. The variables investigated were: (1) Vehicle type; a large full-size car, a compact car and a bus-type vehicle were employed. (2) Radius of turn; 50 and 25 ft to the center of a circular lane. (3) Direction of turn; right and left turns. Twenty-four subjects participated in the study, each driving all cars under all conditions. Significant differences in the location of the mean points of intersection relative to the front bumper within and between cars were associated with the various conditions. Location of the driver eye points relative to the points of intersection differed little, especially in the 25-ft radius condition.