Browse Topic: Wipers and washers

Items (571)
In the current scenario of EV revolution in the automotive industry, NVH performance of the vehicles is one of the major points of sale to the customers. Auxiliary components play one of the predominant roles in the contribution of noise to overall vehicle interior or exterior sound pressure levels, which impact customer vehicle comfort. CAE prediction of NVH performance of automotive components involves a lot of design iterative processes, large server space utilization, and time-consuming. To reduce cost and time, data-driven technologies like AI algorithms can help CAE engineers because of their high efficiency and high precision. In the current research, a wiper motor mount stiffness prediction algorithm was designed based on the historical data using CAE analysis and AI algorithms, and improved prediction accuracy by tuning the parameters of AI algorithms using grid search methodology. High prediction accuracy of wiper motor mount stiffness has been achieved with the method of support vector machine. CAE engineers can avoid iterative processes by utilizing the optimized design parameters from the prediction results without running full finite element analysis simulations.
Paturi, Yuva Venkata Sekhar
In today's dynamic driving environments, reliable rear wiping functionality is essential for maintaining safe rearward visibility. This study sharing the next-generation rear wiper motor assembly that seamlessly integrates the washer nozzle, delivering improved performance alongside key benefits such as better Buzz, Squeak, and Rattle (BSR) characteristics, reduced system complexity, cost savings, and enhanced perceived quality. This integrated design simplifies the hose routing which improves the compactness and the efficiency of the design. This also enhances the spray coverage and minimizes the dry wiping unlike the traditional systems that position the washer nozzle separately. A non-return valve (NRV) is incorporated to eliminate spray delays ass it maintains consistent water flow giving cleaning effectiveness. Since this makes the nonfunctional parts completely leak proof due to the advanced sealing, it increases the durability and reliability in long run. As this proposal offers a sustainable solution, it can be considered as the new benchmark in rear wiper technology.
Dhage, PrashantK, NagarajanG, Sabari Rajan
The modern vehicle electrical architecture consists, on average, of 30 integrated electronic modules (ABS, infotainment, instrument panel, etc.), also known as Electronic Control Units (ECUs), and approximately 300 peripherals such as sensors (collision, temperature, oxygen, position, pressure, etc.) and actuators (window motor, mirror motor, relays, airbag inflator, windshield wiper, etc.). This increase in component integration imposes significant challenges to system installation and design. The interconnection of multiple devices renders harness design an arduous and time-consuming task, especially when conducted manually, resulting in error-prone and suboptimal outcomes. Such a scenario highlights the pressing need for studies on harness routing optimization in the automotive industry. Historically, wiring harness design practices have transitioned from manual approaches to the adoption of advanced computational tools. This methodological transition encompasses the use of various techniques, such as algorithms, 3D simulation, and machine learning, aiming for effective solutions to this complex challenge. In this context, the present work aims to conduct a literature review on wiring harness routing optimization strategies, with an emphasis on their application in vehicular electrical architecture. The current academic literature indicates that advancements in optimization approaches are crucial, especially through the application of methods such as Genetic Algorithms, Agent-Based Modeling and Simulation, Integer Linear Programming (ILP) and Linear Programming (LP) applied to the Steiner Tree Problem, Simulated Annealing, Ant Colony Systems, Particle Swarm, among others. Such methodologies are fundamental not only for developing lighter and more compact harnesses but also for a more efficient exploration of available physical space, culminating in layout development time optimization.
Ribeiro, ThiagoReis, BrenoBarreto, ZeusGaleno, AntônioPereira, MarceloFerreira, Fláavio Fabrício V. M.
This SAE Recommend Practice establishes for passenger cars, light trucks, and multipurpose vehicles with GVW of 4500 kg (10000 pounds) or less, as defined by the EPA, and M1 category vehicles, as defined by the European Commission:
ICTMS Vehicle Manufacturer Committee
Sound source identification based on beamforming is widely used today as a spatial sound field visualization technology in wind tunnel experiments for vehicle development. However, the conventional beamforming technique has its inherent limitation, such as bad spatial resolution at the low frequency range, and limited system dynamic range. To improve the performance, three deconvolution methods CLEAN, CLEAN-SC and DAMAS were investigated and applied to identify wind noise sources on a production car in this paper. After analysis of vehicle exterior wind noise sources distribution, correlation analysis between identified exterior noise sources and interior noise were conducted to study their energy contribution to vehicle interior. The results show that the algorithm CLEAN-SC based on spatial source coherence shows the best capability to remove the sidelobes for the uncorrelated wind noise sources, while CLEAN and DAMAS, which are based on point spread functions have definite limitations. Considering the testing car, the main noise source of exterior is from the wheelhouse region, then follows the rearview mirror with much lower sound energy. However, noise from the mirror contributes most to the vehicle interior, while the contribution from wheelhouse region ranks the second place. In addition, windshield wipers and door handle can do perceptible contributions to vehicle interior noise at some characteristic frequency bands.
He, YinzhiShen, HenghaoWu, YuZhang, LijunYang, ZhigangBlumrich, ReinhardWiedemann, Jochen
This SAE Recommended Practice establishes testing methods and performance requirements for windshield wiping systems on trucks, buses, and multipurpose passenger vehicles with a GVWR of 4500 kg (10000 pounds) or greater and light-duty utility vehicles with a GVWR of less than 4500 kg (10000 pounds). The test procedures and minimum performance requirements outlined in this document are based on currently available engineering data. It is the intent that all portions of the document will be periodically reviewed and revised as additional data regarding windshield wiping system performance are developed.
Truck and Bus Windshield Wipers and Climate Control Comm
This SAE Recommended Practice establishes for trucks, buses, and multipurpose passenger vehicles with GVW of 4500 kg (10 000 lb) or greater: a Minimum performance requirements for the switch for activating electric or electro-pneumatic windshield washer systems. b Uniform test procedures that include those tests that can be conducted on uniform test equipment by commercially available laboratory facilities. The test procedures and minimum performance requirements, outlined in this document, are based on currently available engineering data. It is the intent that all portions of the document will be periodically reviewed and revised as additional data regarding windshield washing system performance is developed.
Truck and Bus Windshield Wipers and Climate Control Comm
This SAE Recommended Practice establishes for trucks, buses, and multipurpose vehicles with GVW of 4500 kg (10 000 lb) or greater: a Minimum performance requirements for the switch for electrically or electro-pneumatically powered windshield wiping systems. b Uniform test procedures that include those tests that can be conducted on uniform test equipment by commercially available laboratory facilities. The test procedures and minimum performance requirements, outlined in this document are based on currently available engineering data. It is the intent that all portions of the document will be periodically reviewed and revised as additional data regarding windshield wiping system performance are developed.
Truck and Bus Windshield Wipers and Climate Control Comm
This SAE Recommended Practice establishes for passenger cars, light trucks, and multipurpose vehicles with GVW of 4500 kg (10000 pounds) or less: a Minimum performance standards for windshield wiper systems. b Test procedures that can be conducted on uniform test equipment by commercially available laboratory facilities. c Uniform terminology of windshield wiper system characteristics and phenomena consistent with those found in guides for the use of engineering layout studies to evaluate system performance. d Guides for the design and location of components of the systems for function, servicing of the system, etc. The test procedures and minimum performance standards outlined in this document are based on currently available engineering data. It is the intent that all portions of the document will be periodically reviewed and revised as additional data regarding windshield wiping system performance are developed.
Wiper Standards Committee
Wrap around distance (WAD) is an important index to evaluate the contact position between pedestrian head and vehicle, and is also one of the key parameters of pedestrian accident reconstruction. The purpose of this paper is to explore whether the pedestrian headform testcan reflect the distribution of head injury in the real world. Firstly, in order to study the distribution of pedestrian head WAD in road accidents in China, a head WAD prediction model was established using logistic regression based on pedestrian height and vehicle collision speed. Secondly, in order to study the distribution of the risk of severe head injuries among pedestrians in accidents, the frequency of pedestrian head impact and the proportion of pedestrian head injury were counted respectively for sedans and SUVs. Subsequently, a risk curve for severe head injuries was constructed based on the head impact frequency and the proportion of severe injuries, utilizing a method that incorporates joint probability. Finally, to investigate the relationship between the headform test results and the distribution of severe head injury risks among pedestrians in road traffic accidents in China, a meticulous regional division of the head WAD was conducted based on the vehicle's front structure. A qualitative comparison was made between the distribution of headform test results in that area and the distribution of pedestrian injuries in the real world within that specific region. The results indicate that the location of pedestrian head impacts is primarily concentrated within the range of WAD 1500 mm to WAD 2300 mm. When pedestrians collide with sedans, the peak frequency of head impact occurs at WAD 1900 mm, whereas in collisions with SUVs, this peak occurs at WAD 1700 mm. In the areas of sedan windshields and A-pillars, as well as the rear portion of SUV hoods and windshield wiper regions, pedestrians' heads are most susceptible to severe injuries. It is noteworthy that within the WAD1000-WAD1500 mm range, the risk of severe head injuries for pedestrians is nearly zero. This study, through the analysis of severe head injury distribution among pedestrians in China, assessed the effectiveness and applicability of The China Insurance Automotive Safety Index (C-IASI) headform test. It provides targeted recommendations for the enhancement of the C-IASI pedestrian assessment protocol and offers crucial reference for optimizing the design of vehicle front structures.
Ye, BinLiu, YuLong, YongchengShi, LiangliangXinming, Wan
The windscreen wiping system is mandatory requirement for automotive vehicle as per Central motor vehicle rules (CMVR). The main scope of the standard is to ensure vision zones to be wiped by wiping system to ensure maximum field of vision to the driver. The evaluation of vision zones as per IS 15802:2008 is generally determined by virtual simulation by OEMs. The limitation of virtual simulation is due to actual tolerances in vehicle, due to seat fitment, ergonomic dimensions, seat cushioning effect and wiper non-effective operation which are not taken into consideration very well off. The testing methodology described in the paper is an in-house developed test method based on SAE recommended practices. With the help of 3D H-point machine and a laser based ‘Theodolite’ equipped with horizontal and vertical angle projections from single pivot point is used to develop various vision zones on an actual vehicle windscreen as per technical data. These zones are later compared with wiped area to evaluate field of vision. The standard is applicable to vehicle other than M1 category viz M2, M3, N1, N2 and N3. Critical vehicle parameters such as SgRP (seating reference point), seat back angle and AHP (accelerator heel point), seat travel, GVW (gross vehicle weight) and category of the vehicle are required. The paper clearly describes calculation steps for calculating Automotive tool reference line, equation for Eye ellipse, placing eye ellipsoide centroid coordinates with respect to VCS (vehicle coordinate system) in vehicle ecosystem, projecting Ellipse tangents for distinct vision zones and evaluating mandatory standard requirement of percentage of wiped area with respect to vision zones at vehicle level. The work scope in this paper will enable manufactures to validate the virtual simulation results with respect to actual vehicle considering all tolerances. This test method can be adapted widely to evaluate more precise test results and data for field of vision certification activity.
Joshi, AmolPatil, AmolDoshi, AnupNikam, ShashankBelavadi Venkataramaiah, Shamsundara
In recent years, demands of flat wipers have rapidly increased in the vehicle industry due to their simpler structure compared to the conventional wipers. Procedures for evaluating the appropriate metallic flexor geometry, which is one of the major components of the flat wiper, were proposed in the authors’ previous study. However, the computational cost of the aforementioned procedures seems to be unaffordable to the industry. The discrete Winkler model regarding the flexor as the Euler–Bernoulli beam is established as the mathematical model in this study to simulate a flexor compressed against a surface at various wiping angles. The deflection of the beam is solved using a finite difference method, and the calculated contact pressure distributions agree fairly with those based on the corresponding finite element model. Flexor designs are paired with various windshield surfaces to accumulate a sufficiently large simulation database based on the mathematical model. An artificial neural network (ANN) approach is developed to predict contact pressure distributions of the flexor much faster than the mathematical model. Geometry of the curved surface is represented by a shape code obtained via a principal component analysis (PCA) and used in the ANN model. The ANN algorithm is also applied to efficiently evaluate the wiping patterns according to the simulated contact pressure distributions. These patterns are then classified by using a convolutional neural network (CNN) to identify several suitable flexor designs for the specific windshield. The flat wiper suggested by the current procedures is experimentally validated to justify its qualified wiping performances.
Chu, Yi-TzuHuang, Ting-ChuanLiao, Kuo-Chi
In the late 1970’s and early 1980’s, Jing-Yau Chung along with Joseph Pope published several external General Motors reports on the then novel measurement of sound intensity (SI) using the two-microphone, cross-spectral method. Application of this measurement method was then extended to sound intensity measurements in flow. Through component wind tunnel measurements, it was determined that the intensity of noise sources could be accurately measured up to a level of 15 dB below the sound pressure level generated by flow noise on microphones. An initial application of this method was to the identification of noise sources alongside rolling truck tires. It was then extended to the measurement of the aerodynamic noise generated by protrusions added to automotive vehicle designs. These included items such as outside rearview mirrors, windshield wipers, A-pillar offsets, grille whistles, roof racks, underbodies, and fixed-mast radio antennas. Many of these could be applied on the early full-size clay models or other mock-ups as well as actual vehicles. An application of sound intensity was the development of the straked antenna design leading to a GM Defensive Patent and its now universal application to virtually all vehicles with simple fixed-mast antennas. The development of this design is highlighted along with the background on the application of sound intensity to measurements in air flow.
Donavan, Paul R.
The primary function of automotive windscreen wipers is to remove excess water and debris to secure a clear view for the driver. Their successful operation is imperative to vehicle occupants’ safety. To avoid reliance on experimental testing there is a need to develop physics-based models that can quantify the effects of design-based decisions on automotive wipers. This work presents a suite of evaluative tools that can provide quantitative data on the effects of design decisions. We analyse the complex non-linear contact interaction between the wiper blade and the automotive screen using finite element analysis, assessing the impact of blade geometry on the contact distribution. The influence of the evolution of normal applied load by the wiper arm is also investigated as to how it impacts the contact distribution evolution. The dynamics of the blade are subsequently analysed using a multiple connected mass spring damper system. Additionally, we apply hydrodynamic lubrication theory to study the residual film thickness post wipe and assess the effect of wiper blade geometry and lubricant composition. Finally, the complete wiper system is studied using a lump dynamic model, and bifurcation analysis is applied to determine areas of instability due to friction induced vibrations. Additionally, the wiper dynamics modelling shows peak frequencies occurring at 30-50Hz, which agrees well with a documented range of chatter frequencies. The friction coefficients calculated within the hydrodynamic model fall within experimentally documented ranges of lubricated sliding friction, μ ≈ 0.1. Furthermore, the areas of operational stability predicted by our bifurcation model coincide with current experimentally determined optimal operational regions for automotive wipers.
Graham, BradleyKnowles, JamesMavros, George
The requirements of the automotive industry move along due to product competitiveness and this contributes to increase complexity in the requirements for evaluation. Simulation tools play a key role thanks to their versatility and multiple physical phenomena that can be represented. The axis of analysis for this paper is the problem of the interaction of airflow and water flow in the cowl/plenum/leaf screen components. Airflow is represented by HVAC system operating and water flow by the vehicle in torrential rain. Initially, one simulation is evaluated at a time, in one side, the airflow entering the HVAC system in which the amount of air entering is monitored and pressure drop, on the other, the water simulation on the vehicle, both using a Lagrangian CFD model (using with tools such as STAR CCM+® or Ansys Fluent®) Due to this, a CFD methodology was developed to evaluate the interaction of air and water flow. This uses CFD Eulerian model for airflow and a Lagrangian model for water, in which results from the initial simulation are included to evaluate the interaction of both fluids and consequently obtain a more significant result for water particle behavior. The research results show a significant change in the amount of water distribution in the system when it has airflow as an initial boundary condition. Furthermore, the kinematics of the windshield wipers is another key factor in the study, and it changes the physics of this analysis, which is currently under development to provide more effective results.
Alonso, LilianaSaavedra, OscarRuiz, Josias
The Class A Task Force of the Vehicle Network for Multiplexing and Data Communications Subcommittee is providing information on sensors that could be applicable for a Class A Bus application. Sensors are generally defined as any device that inputs information onto the bus. Sensors can be an input controlled by the operator or an input that provides the feedback or status of a monitored vehicle function. Although there is a list of sensors provided, this list is not all-inclusive. This SAE Information Report is intended to help the network system engineer and is meant to stimulate the design thought process.
Vehicle Architecture For Data Communications Standards
This SAE Aerospace Recommended Practice (ARP) covers specification requirements for a rotary plow with carrier vehicle. The primary use is to cast heavy concentrations of snow approximately perpendicular to carrier vehicles across and away from airport operational areas, such as runways and taxiways. Rotary plows equipped with spot casting, or loading chutes are also used to cast snow in directions through approximately 100 degrees to the left or right of directly in front of the carrier vehicle, and also to load trucks or trailers used to haul snow away from removal area. The term “carrier vehicle” represents the various self-propelled prime movers that provide the power necessary to move snow and ice control equipment during winter operations.
G-15 Airport Snow and Ice Control Equipment Committee
The most widely used type of windshield wiper system employs a coil spring for wiper arm pressure generation. This spring is fixed between the arm head (fixed part) and wiper arm (moving part) and the tension in the spring is responsible for pressure generation. The present arrangement although being unsophisticated design, has following drawbacks: Inability to change wiper arm pressure according to change in vehicle speed. Inability to provide constant arm pressure during the complete range of motion along varying curvature of windshield. Inability to reduce/remove the continuous pressure on wiper blade when vehicle is parked for long durations resulting in permanent deformation of wiper blade rubber. This paper describes how electromagnets can be used to overcome the above stated inherent limitations of the windshield wiper system. An electromagnet is a device which produces magnetic field on application of electric current. It consists of electrical conductor wound around a magnetic core. Unlike a permanent magnet whose magnetic field is fixed, the magnetic field produced by electromagnets can be changed or even reversed very quickly by controlling the input current. Since, magnetic fields attract or repel each other depending upon their direction, hence, electromagnets can be used to produce variable force of attraction or repulsion. This enables electromagnets to be used as a spring with adjustable stiffness.
Yadav, BhuvneshwarShah, PrateekAHMAD, ZUBERSahrawat, DineshRaina, Sandeep
SAE J3078/5 specifies a test method for testing defrosting systems. It is applicable to off-road self-propelled work machines as defined in SAE J1116 and agricultural tractors as defined in ANSI/ASAE S390. The full list of machines covered is included in Table 1.
HFTC6, Operator Accommodation
This SAE Recommended Practice is intended as a guide toward standard practice and is subject to change to keep pace with experience and technical advances. This document provides standardized laboratory tests, test methods and equipment, and requirements for lighting devices covered by SAE Recommended Practices and Standards. It is intended for devices used on vehicles less than 2032 mm in width. Tests for vehicles larger than 2032 mm in overall width are covered in SAE J2139. Device specific tests and requirements can be found in applicable SAE technical reports.
Test Methods and Equipment Stds Committee
The increasingly important need to design simpler structures, reducing the number of constituent components, has motivated the approach outlined in this article, which proposes an effective reengineering example of a product belonging to the automotive industry, combining the advantages offered by the compliant mechanisms with production opportunities linked to the use of additive manufacturing. Taking advantage of compliant mechanisms makes it possible to significantly improve the component’s production phase, leading to undoubted benefits on the supply chain and on product’s time to market, benefits made possible by exploiting the outstanding characteristic of additive manufacturing to produce already assembled multi-material structures. The performances of the innovative monocomponent wiper designed here were compared, with the help of finite element method (FEM) simulations, with those of the component made in the traditional way and with those of the only other existing single-component frame of which we have news, the one patented by the United States (US) company Flexsys, obtaining satisfactory results both in terms of weight reduction, for the best pressure distribution at the wiper/glass interface, and in terms of maximum stress reduction.
Pantano, AntonioMinore, GemmaCarollo, Giovanni
This Aerospace Information Report (AIR) is presented in two parts. The first part is simply a summarization of design factors that must be considered in establishing vehicle specifications and design characteristics. The second part refers particularly to the performance characteristics of an aircraft tow tractor. Some definitions, formulas, data, and an example are provided mainly for assisting the specifying engineers of potential buyers and users of aircraft tow tractors in the evaluation and comparison of their requirements with the performance capabilities of the various tow tractors offered by the tow tractor manufacturers. Although the design engineers could also use the formulas and data in their calculations of the performance specifications of aircraft tow tractors, this AIR is not intended to provide the methods and all data necessary for detailed calculations and design of an aircraft tow tractor.
AGE-3 Aircraft Ground Support Equipment Committee
This SAE Recommended Practice provides test procedures, performance requirements, and guidelines for cleaners intended for use on motor vehicles.
Road Illumination Devices Standards Committee
This SAE Recommended Practice establishes testing methods and performance requirements for windshield wiping systems on trucks, buses, and multipurpose passenger vehicles with a GVWR of 4500 kg (10000 pounds) or greater and light duty utility vehicles with a GVWR of less than 4500 kg (10000 pounds). The test procedures and minimum performance requirements, outlined in this document, are based on currently available engineering data. It is the intent that all portions of the document will be periodically reviewed and revised as additional data regarding windshield wiping system performance are developed.
Truck and Bus Windshield Wipers and Climate Control Comm
This SAE Recommended Practice establishes uniform test procedures and performance requirements for the defrosting system of enclosed cab trucks, buses, and multipurpose vehicles. It is limited to a test that can be conducted on uniform test equipment in commercially available laboratory facilities. For laboratory evaluation of defroster systems, current engineering practice prescribes that an ice coating of known thickness be applied to the windshield and left- and right-hand side windows to provide more uniform and repeatable test restults, even though—under actual conditions—such a coating would necessarily be scraped off before driving. The test condition, therefore, represents a more severe condition than the actual condition, where the defroster system must merely be capable of maintaining a cleared viewing area. Because of the special nature of the operation of most of these vehicles (where vehicles are generally kept in a garage or warmed up before driving), and since defrosting under steady-state over-the-road operations is the main concern, test conditions have been adopted which assume that the engine is warm before the vehicle is driven. There are two options for producing hot coolant in this recommended practice. Testing using these two approaches on the same vehicle will not necessarily provide identical results. Many vehicle models are offered with optional engines, and each engine has varying coolant temperatures and flow rates. If the test is being conducted to compare the performance of one defroster design to another defroster design, then the external coolant source approach (Test A) will yield the most comparable results. If the test is being conducted to validate the defroster installation on a specific vehicle model with a specific engine, then using the engine to heat the coolant (Test B) will be more appropriate. This document will be reviewed and revised as technological progress in vehicle defroster test procedure requires.
Truck and Bus Windshield Wipers and Climate Control Comm
The windshield wiper is a component that is closely related to safety because it plays an important role in ensuring the driver’s vision despite external factors such as rain and dust. Here, the mechanical properties of different types of blade rubber were evaluated using a miniature tensile test machine for a structural analysis of the types of wiper blade rubber used in automobiles. In addition, a compression set and the aging characteristics of each type of rubber were determined by comparing the mechanical properties and shape changes of the blade rubber after more than one year of use to the same blade rubber before use. Using the mechanical properties as measured by a tensile test, a nonlinear structural analysis of the wiper blade system was conducted using a 3D finite element method (FEM). The contact force distribution and wiping angle of the blade rubber under a static load were measured. According to the structural analysis, there is a difference in the wiping angle of more than 30° and a difference in the contact force distribution of more than 1.5 times between the new rubber and the old rubber. A sensitivity analysis was conducted using the design of experiments (DOE)-derived three main factors affecting the cross section of the blade rubber. Based on the main factors, the effects of the wiper blade’s cross-sectional shape on the angle and contact force distribution were analyzed using the response surface method (RSM). When a static load of 2 N is applied and when the width of the web reaches 0.75 mm, the length of the web is 0.9 mm, and the tip width is 0.65 mm, the contact force distribution range is reduced, and the wiping angle is in the normal range. The results of this study indicate that it is possible to predict the main factors and the design direction of the cross-sectional shape of a wiper blade.
Lee, Chae-EunKim, Ho-Kyung
Visibility is a critical factor to avoid the accidents and incidents on road. Every year there are over 5 million car accidents reported in USA. Of these 23% are caused by the hazardous weather and poor visibility. Driving in poor visibility increases the potential for a serious crash. Over the last decade 15% of the accidents on road are due to poor visibility in bad weather conditions. This paper addresses the poor visibility through the rear windshield glass of a car. A vehicle is designed in a way to provide the maximum possible visibility. But due to the vehicle design constraints, the visibility through the rear glass is very less. This visibility reduces drastically in the extreme weather conditions like rain, snow, dust and fog. At present, wiper systems play an essential role in providing better visibility for the driver in bad weather. Even though there are other technological aids like cameras, sensors etc.., they come with a high cost and act as only passive visibility for the driver. These cannot give as much confidence to the driver as his own eyes can. The wiping systems for front windshield glass, in terms of wiping area, are very efficient compared to the rear glass wiper systems. The rear wiper arm length is very less, mainly due to the height of the glass. This combined with the conventional motion of wiper arm, results in a low wiping area, leading to poor visibility for the driver. This paper addresses this problem with a simple solution using a telescopic wiper system with cam and roller mechanism.
Masimukku, Venkata AravindMSVS, Karthik
This SAE Recommend Practice establishes for passenger cars, light trucks, and multipurpose vehicles with GVW of 4500 kg (10000 pounds) or less, as defined by EPA, and M1 category vehicles as defined by the European Commission:
ICTMS Vehicle Manufacturer Committee
E-25 General Standards for Aerospace and Propulsion Systems
The magnitude of the turbulent pressure spectrum in fluid flow over an obstruction is usually much larger than in attached flow over a smooth surface. External features on a vehicle, such as windshield wipers, side mirrors and pillars which cause flow separation, are a major source of wind noise. The modeling of the pressure spectrum in separated flow is important for designing quiet vehicles. In this study wind tunnel tests have been performed with different shaped obstructions to measure and correlate the surface pressure spectra with flow parameters such as the pressure coefficient and separation size. The model by Chase for attached turbulent boundary layer pressures is generalized to apply to separated flow conditions.
DeJong, RichardDeVries, Kurtis
Development of Brushless Smart Motor for Front Wipers2019-01-06104/2/2019
Along with the auto industry’s proactive engagement in autonomous driving and the development of hybrid electric vehicles (HEVs) and electric vehicles (EVs) driven by regulatory compliance for vehicle emissions control and fuel economy, there is a growing need for quieter, lighter, more compact and efficient designs of electronic components for automobiles. For wiper functions, the demand for improving wiping performance at high driving speeds and increasing wiped areas is on the rise. To fulfill all these needs, this project aimed to develop the world’s first brushless controlled wiper system, focusing on the following key elements: 1) power efficiency improvement and noise reduction through an effective sensing design and control methods of field weakening and wide-angle commutation, and 2) lightweight and compact design by reducing the weight and shaft length. The first challenge was to minimize power consumption in consideration of constant load changes during wiper operation as well as reducing the motor noise. With the correction method applied to the sensing design and the field weakening control and the wide-angle commutation control, the final design reduced the power consumption by 30% and the sound level by approximately 6 dB, compared to conventional brush motors. To achieve the second goal, we changed the magnetic circuit configurations, which reduced the rotor inertia. This outcome helped change the rotor assembly structure into a single-sided support design, eliminating the bearing placed on the end cover (the housing for the rotor and stator). These design considerations and the material change of the end cover helped reduce the motor length by 30% and the weight by 20%, contributing to a lighter design. Thus, we successfully developed the world’s lightest and smallest brushless wiper motor, featuring its cutting-edge structure and control design. The product was released into the market as the world’s first brushless wiper motor.
Annaka, TomohikoKojima, NaokiIkeda, TakeshiKimura, Masaaki
Numerical Investigation of Wiper Drawback2019-01-06404/2/2019
Windscreen wipers are an integral component of the windscreen cleaning systems of most vehicles, trains, cars, trucks, boats and some planes. Wipers are used to clear rain, snow, and dirt from the windscreen pushing the water from the wiped surface. Under certain conditions however, water which has been driven to the edge of the windscreen by the wiper can be drawn back into the driver’s field of view by aerodynamic forces introduced by the wiper motion. This is wiper drawback, an undesirable phenomenon as the water which is drawn back on to the windscreen can reduce driver’s vision and makes the wiper less effective. The phenomena of wiper drawback can be tested for in climatic tunnels using sprayer systems to wet the windscreen. However, these tests require a bespoke test property or prototype vehicle, which means that the tests are done fairly late in the development of the vehicle. Furthermore, these results do not provide significant insight into the mechanisms driving the wiper drawback. In order to better understand wiper drawback a numerical simulation is presented of a configuration known to exhibit this phenomenon. This requires the inclusion into an aerodynamics solver of: moving wipers, a surface film model, and a representation of airborne spray. Using the results of this simulation, the forces causing the drawback of the water film, along with the mechanism for introducing these forces are studied. Through understanding the driving factors in wiper drawback, it can be avoided earlier in the development cycle.
Jilesen, JonathanGaylard, AdrianLinden, Tom
The wiper system consists of a motor, linkage, arm, and blade, which provides a clear front view to the driver by removing rain, snow, and foreign matter from the windshield glass. It is a system component that requires a robust design to meet system rigidity, scrubbing performance, and operating noise to any external conditions to provide the driver with a front view. In recent years, however, customer complaints about wiper noise have increased as automobile engine and noise levels have decreased. Based on the analysis of wiper noise, this paper presents quantitative judgment criteria for various wiper noises. In addition, we predict the change of wiper noise to environmental factors through the sound field analysis and propose the solution.
Kong, Nak KyoungLee, KihongPark, Jongmin
E-25 General Standards for Aerospace and Propulsion Systems
E-25 General Standards for Aerospace and Propulsion Systems
E-25 General Standards for Aerospace and Propulsion Systems
E-25 General Standards for Aerospace and Propulsion Systems
E-25 General Standards for Aerospace and Propulsion Systems
E-25 General Standards for Aerospace and Propulsion Systems
The purpose of this document is to define: - compensation washer application requirements - recommended materials - washer thickness determination - dimensioning
E-25 General Standards for Aerospace and Propulsion Systems
E-25 General Standards for Aerospace and Propulsion Systems
In India, vehicle population increases every day along with road accidents by 2.5% every year. About 7.7% of accidents are caused by wheel separation, 60% of which are due to nut-related problems. Wheel separations in vehicles occur due to fastener issues and fatigue failures in bolts. A study of the reasons for and mechanisms of nut loosening showed that left-hand side wheels detached and fracture failure occurred in right-hand side studs. Fatigue life of wheels with Nord-Lock washer and without washer is determined by using numerical analysis as per the IS 9438 cornering fatigue test. These numerical results are compared with experimental results.
Bawaskar, Umesh SadashivAwasare, P.
This SAE Recommended Practice is intended as a guide toward standard practice and is subject to change to keep pace with experience and technical advances. This document provides standardized laboratory tests, test methods and equipment, and requirements for lighting devices covered by SAE Recommended Practices and Standards. It is intended for devices used on vehicles less than 2032 mm in width. Tests for vehicles larger than 2032 mm in overall width are covered in SAE J2139. Device specific tests and requirements can be found in applicable SAE technical reports.
Test Methods and Equipment Stds Committee
Plenum is the part located between the front windshield and the bonnet of an automobile . It is primarily used as an air inlet to the HVAC during fresh air mode operation. It’s secondary functions include water drainage, aesthetic cover to hide the gap between windshield to bonnet, concealing wiper motors and mechanisms etc. The plenum consists mainly two sub parts viz. upper plenum and lower plenum. Conventional plenum design which is found in majority of global OEMs employ a plastic upper plenum and a metal lower plenum which spans across the entire width of engine compartment. This conventional lower plenum is bulky, consumes more packaging space and has more weight. In this paper, we propose a novel design for the plenum lower to overcome above mentioned limitations of the conventional design. This novel design employs a dry and wet box concept for its working and is made up of complete plastic material. This proposed design consumes only about 1/3rd of the packaging volume with a weight savings of up to 50% compared to a conventional plenum in similar class of vehicles. This novel design is of modular architecture. This enables the design to have a potential of standalone unit which can be cross deployed in similar class of vehicles instead of going for new development, thus allowing significant cost savings. An optimized and structured approach for testing of the plenum is derived to correlate testing conditions in the real world conditions. The proposed new plenum design is observed to perform better in all test parameters and was implemented on vehicle.
Kumar, PraveenKV Shenoy, VivekKinthala, NareenSudhir, Srikanth
ACBG Plain Bearing Committee
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