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”U” bolts are fixing elements and they are used to clamp an elastic joint. From the past, they still looking as an old design and unfortunately, suspension engineers are not specialists in fasteners and elastic joints. That is why we will show important assumptions and concepts to design and specifications this clamp element “U” bolt and its influence over leaf-springs. Currently, “U” bolt is used to clamp an elastic or elastic-plastic joint of heavy duty suspension, formed by leaf-spring, axle, spring pad, “U” bolt plate. This kind of suspension is typically used to trucks, buses and trailers. We are wondering, which one important assumption that an engineer must be careful when designs a new suspension changing from old designs to an updated technology. We provide a theoretical analysis and a FEA analysis to compare torque efficacy x leaf-spring reactions and what are effects this relationship can cause in a suspension.

The “middle man” in the construction machinery business is the dealer who sells and services the products designed and built by the engineers and scientists of the industry. Quality is a foremost concern of the dealer and second, only to quality, is the need for cost control.

Collins Aerospace, a subsidiary of United Technologies Corporation (UTC), has laid out its plans for what is calling “The Grid” – an 25,000-square-foot advanced electric power systems laboratory for designing and testing next-generation, more-electric aircraft technologies for commercial, military, and business aviation.

Many newer commercial vehicles have an event data recorder (EDR) that can record pre-event and post-event speeds. The EDR is incorporated into the engines electronic control module (ECM). In this study, the accuracy of the ECM-reported speed was tested during acceleration, gear shifting and braking at speeds between 16 and 88 km/h (10 to 55mph). The ECM-reported speed was compared to the speed measured by a calibrated optical 5th wheel. The results showed that the accuracy of the ECM-reported speed matched closely during acceleration, cycled to periods of under-reporting the speed during hard braking due to the ABS brake function, briefly under-reporting the speed after letting off the throttle for braking or gear shift and briefly over-reporting the speed near the end of a gear shift phase. This study also looked at calibration factors of the ECM and their effect on the ECM-reported speed.

This paper describes some of the design solutions adopted in solving two major problems besetting man-powered aircraft in use: that of breakage and storage. It describes work leading up to the building and testing of “Phoenix”, a man-powered aircraft with a polyester-film inflatable wing. The paper deals mainly with aspects relating to the wing design and construction.

Research information on solid lubricants has been compiled for consideration in the possible use of such materials in aircraft electrical equipment. Solid lubricants are capable of lubricating at the maximum temperatures (600° F) for aircraft electrical equipment. Many solids that adhere well to metals may be useful lubricants; those with layer-lattice structure usually give low friction. Solid lubricants are most commonly used as bonded films but the use of fluid carriers and surface reaction products have considerable merit.

Energy demand climbs as a consequence of the inherent relationship between the rate of consumption of energy and the growth of the economy. In light of the depletion of fossil fuels, it is necessary to implement energy efficiency techniques and policies that support sustainable development. Globally, researchers show more interest in discovering fossil fuel alternatives, as a result of fuel crisis. This research elaborates on the production and experimental investigation of briquettes made from ideal municipal solid waste (MSW), such as food waste and garden waste, as a feasible choice for alternate fossil fuels. From Municipal, agricultural, and food waste, we can get biomass waste. Municipal solid and agricultural waste is extensively dispersed, but their potential for converting biomass into energy generation still needs to be explored. This study was carried out based on the information gathered from various studies published in the scientific literature.

This paper is an extension of our previous work on the CHASE (Classification by Holistic Analysis of Scene Environment) algorithm, that automatically classifies the driving complexity of a road scene image during day-time conditions and assigns it an ‘Ease of Driving’ (EoD) score. At night, apart from traffic variations and road type conditions, illumination changes are a major predominant factor that affect the road visibility and the driving easiness. In order to resolve the problem of analyzing the driving complexity of roads at night, a brightness detection module is incorporated in our end-to-end nighttime EoD system, which computes the ‘brightness factor’ (bright or dark) for that given night-time road scene. The brightness factor along with a multi-level machine learning classifier is then used to classify the EoD score for a night-time road scene. Our end-to-end ‘Night-time EoD system’ is a real-time onboard system implemented and tested on road scene data collected in Japan.

Prior theoretical work relating barrier equivalent velocity (BEV) and change in vehicle velocity, ΔV, has either neglected restitution or mischaracterized its role. Based on fundamental structural dynamics principles, improved relationships between BEV, ΔV, coefficient of restitution, and vehicle mass and stiffness are formulated. These corrected relationships are then utilized in the assessment of four classes of vehicular impact testing: vehicle to vehicle (VTV), vehicle to infinitely massive rigid barrier (VRB), vehicle to infinitely massive compliant barrier (VCB) and vehicle to finite mass movable rigid barrier (VFMB).

THE NEED for greater speed in military aircraft and missiles is, without question, the primary force behind the current quest for lubricants of increased thermal and oxidative stability. Turbojet engines soon to be available will require improved lubricants for trouble-free operation. Once developed, these oils may find use in the engines of future civilian aircraft as well as in a variety of special applications. It is the purpose of this paper to discuss the results of an experimental program in the field of high-temperature lubricants. Problems of relating chemical structure to the physical properties and performance of highly fluorinared ester lubricants will be described. Background information in the field of turbojet engine lubrication will be presented.

The effect of vehicle acceleration history on dummy loading in the frontal impact NCAP event is explored with help of a one-dimensional mathematical model. Both numerical and analytical approaches are used to identify the ideal vehicle pulse. The numerical solution reveals limitations of square wave pulse. The analytical approach results in explicit formulation of the ideal pulse. Response of the mathematical model used in this paper is statistically correlated to a number of randomly selected NCAP frontal tests. Both the baseline model and the resulting optimized pulse are also confirmed using a validated three-dimensional Madymo model. Based on the analytical results, a simple measure of quality of the vehicle acceleration history is formulated.

In this paper, a gain-scheduling optimal control approach is proposed to enhance yaw stability of articulated commercial vehicles through active braking of the proper wheel(s). For this purpose, an optimal feedback control is used to design a family of yaw moment controllers considering a broad range of vehicle velocities. The yaw moment controller is designed such that the instantaneous tractor yaw rate and articulation angle responses are forced to track the target values at each specific vehicle velocity. A gain scheduling mechanism is subsequently constructed via interpolations among the controllers. Furthermore, yaw moments derived from the proposed controller are realized by braking torque distribution among the appropriate wheels. The effectiveness of the proposed yaw stability control scheme is evaluated through software-in-the-loop (SIL) co-simulations involving Matlab/Simulink and TruckSim under lane change maneuvers.

In the current Ford Pro-Trailer Backup Assist (TBA) system, trailer hitch angle is determined utilizing the reverse camera of the vehicle. In addition to being sensitive to environmental factors such as lighting conditions and occlusion, the vision-based approach is difficult to be applied to gooseneck or fifth wheel trailers. In this paper, a yaw rate based hitch angle observer is proposed as an alternative sensing solution for TBA. Based on the kinematic model of the vehicle-trailer, an instantaneous hitch angle is first derived by utilizing vehicle yaw rate, trailer yaw rate, vehicle velocity and vehicle/trailer parameters provided by the TBA system. Due to signal errors and parameter uncertainties, this instantaneous hitch angle may be noisy, especially at lower vehicle speed.

HID as lightsource in the automotive world has been proven as the most efficient way to satisfy the main user's requirements on a headlighting bulb: Realize a broad beam pattern with superior performance on visibility, safety and comfort on the one hand, and the fulfillment of long lifetime requirements on the other hand. In the second step, the logical integration of functions and the improvement of automotive system requests such as size and EMC has to be covered. An integrated bulb with starter is the appropriate way to combine these features: Optimized fine tuning between the entire lightsource and the starter to reach optimal electrical and EMI performance on the one side on the other side combined with very compact sizes leads to an automotive source perfectly suiting to the modern trends in headlighting applications.

This study presents results from x-ray analysis of live human head/neck motion in sled test simulations of low-speed frontal, lateral, and rear-end vehicle impacts. The test subjects were 26 male and female adults, aged 22 to 61 years. Head/neck motion and the kinematic responses of each test subject were measured and analyzed by cineradiograph, high-speed film, accelerometers, and electromyography of the neck muscles. The methodology used may provide insight into the mechanism of neck injuries caused by the head inertia loading. The actual kinematic responses of the head/neck were found to be more complex than previously thought. The experimental results suggest that the most significant factor of the head/neck response is the initial curvature of the cervical and thoracic spine. Looking specifically at the early motion of the head and neck in rear-end impacts, the cervical forward curvature (lordosis) and the thoracic rearward curvature (kyphosis) were found to straighten.

Having demonstrated the feasibility of using X-rays derived from high current industrial electron beam accelerators (EB) to cure the matrices of carbon fiber composites and then scaled this up to cure large sized, non-structural automobile components, performance car hoods, the New York State Vehicle Composites Program had a chassis designed, a cured epoxy mold made and then the chassis matrix cured using X-rays with a formulated radiation responsive matrix material. A feasibility study had shown how X-rays could cure through materials embedded within the composite layers, such as metal inserts that could be used for mechanical fastening without fracturing the composite. In producing X-ray cured hoods, the power consumption for X-ray curing was found to be more than 20% lower than that needed for autoclave curing the same sized hoods using conventional thermosetting pre-pregs. More significant was the time-to-cure.

The results of biomechanical testing of the WorldSID prototype dummy are presented in this paper. The WorldSID dummy is a new, advanced Worldwide Side Impact Dummy that has the anthropometry of a mid-sized adult male. The first prototype of this dummy has been evaluated by the WorldSID Task Group against previously established corridors for its critical body regions. The response corridors are defined in the International Organization of Standardization (ISO) Technical Report 9790. The prototype is the first version of the WorldSID dummy to be built and tested. This dummy has been subjected to a rigorous program of testing to evaluate, first and foremost its biofidelity, but also its repeatability. Following this initial evaluation, any required modifications will be incorporated into a pre-production version of the WorldSID dummy so that it rates “good” to “excellent” on the ISO dummy biofidelity scale – a rating exceeding that of all current side impact dummies.

Accident studies indicate that serious neck injuries are generally infrequent in side crashes. However, given the rapid changes in side impact protection technology, such as side airbags and curtain systems, the nature of head-neck interactions is likely to change. Consequently, the newest generation of anthropomorphic test devices for side impact should provide realistic prediction of the head-neck kinematics and include meaningful measurements related to risk of head and neck injury. The WorldSID dummy has been assessed against a set of five test conditions that have been used to define biofidelity impact response targets. Three of the five test conditions are recommended by ISO TR9790 (ISO 1997), the NBDL 7.2 G, 6.9 m/s lateral sled impact reported by Ewing et al. (1977) and Wismans et al. (1986), the Patrick and Chou lateral, 6.7 G 5.8 m/s (1976) and Tarriere lateral 12.2 g, 6,1 m/s sled impact (ISO 1997).

The WorldSID 5th percentile dummy, representing an average female, was developed in less than three years after the WorldSID 50th percentile dummy production release. This 5th percentile dummy was developed in the Integrated Project Aprosys (Advanced Protection Systems) under the European Commission Framework Program 6. This paper discusses the rationale for the WorldSID 5th percentile dummy design and development, and biofidelity evaluation results of head drop test, neck pendulum test and pendulum impact tests of the shoulder, thorax, abdomen and pelvis according to ISO TR9790 (ISO 1997) and Irwin (2002). The dummy was designed to host four units of 32 channel in-dummy Data Acquisition System with total 128 channel capacity. The head is constructed with PVC skin and plastic skull to simulate human head structure. The neck consists of a rubber design with metal discs, which can be tuned with rubber buffers.