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Forward collision warning is one of the most challenging concerns in the safety of autonomous vehicles. A cooperation between many sensors such as LIDAR, Radar and camera helps to enhance the safety. Apart from the importance of having a reliable object detector, the safety system should have requisite capabilities to make reasonable decisions in the moment. In this work, we concentrate on detecting front vehicles of autonomous cars using a monocular camera, beyond only a detection method. In fact, we devise a solution based on a cooperation between a deep object detector and a reinforcement learning method to provide forward collision warning signals. The proposed method models the relation between acceleration, distance and collision point using the area of the bounding box related to the front vehicle. An agent of learning automata as a reinforcement learning method interacts with the environment to learn how to behave in eclectic hazardous situations.

This paper is based on, and in continuation of the work previously published in ASEE NCS Conference held in Grand Rapids, MI [1]. Automotive seating rail structures are one of the key components in the automotive industry because they carry the entire weight of passenger and they hold the structure for seating foams and other assembled key components such as side airbag and seatbelt systems. The entire seating is supported firmly and attached to the bottom bodywork of the vehicle through the linkage assembly called the seat rails. Seat rails are adjustable in their longitudinal motion which plays an important role in giving the passengers enough leg room to make them feel comfortable. Therefore, seat rails under the various operating conditions, should be able to withstand the weight of the passenger along with the other assembled parts as mentioned above. Also, functional requirements such as crash safety is very important to avoid or to minimize injuries to the occupants.

Due to the nearly silent operation of an electric motor, it is difficult for pedestrians to detect an approaching electric vehicle. To address this safety concern, the National Highway Traffic Safety Administration issued the Federal Motor Vehicle Safety Standard (FMVSS) No. 141, “Minimum Sound Requirements for Hybrid and Electric Vehicles”. This FMVSS 141 standard requires the measurement of electric vehicle noise according to certain test protocols; however, performing these tests can be difficult since inconsistent results can occur in the presence of transient background noise. Methods to isolate background noise during static sound measurements have already been established, though these methods are not directly applicable to a pass-by noise test where neither the background noise nor the vehicle itself as it travels past the microphone produce stationary sound signals.

The objective of this study was to determine risk of injury to the driver during a frontal impact in a Formula SAE vehicle. Formula SAE is a collegiate student design competition where every year universities worldwide build and compete with open-wheel formula-style race cars. Formula SAE 2006 rules stipulate the use of an impact attenuator to absorb energy in the event of a frontal impact. These rules mandated an average deceleration not to exceed 20-g from a speed of 7.0 m/s (23 ft/s), but do not specify a specific time or pulse shape of the deceleration. The pulse shapes tested in this study included an early high-g, constant-g, and late high-g pulse. The tests were performed using the deceleration sled at the Kettering University Crash Safety Center. Using industry standard practices, this study examined the driver's risk of injury with regard to neck and femur loads, head and chest accelerations, as well as kinematic analysis using high speed video.

The current study was designed to compare the surface anatomy of the knee for different human subject anthropometries using a 3-D, non-contact digitizer which converted the anatomy into point clouds. The subjects were studied at flexion angles of 60, 90, and 120 degrees. Multiple subjects fitting narrow anthropometrical specifications were studied: 5th percentile female, 50th percentile male, and 95th percentile male. These data were then compared to a corresponding anthropometrical crash dummy knee which served as an unambiguous control. Intersubject human comparisons showed surface geometry variations which were an order of magnitude smaller than comparisons between the human and dummy knee. Large errors between the human and dummy were associated with the muscle bulk proximal and distal to the popliteal region and the rounder shape of the human knee.

FMVSS 223 and 224 set standards for “Rear Impact Protection” for trailers and semi-trailers with a gross weight rating greater than 10000 pounds. A limited amount of experimental data is available for evaluating the different performance attributes of rear impact guards. The crash tests are usually limited to fixed parameters such as impact speed, guard height, strength and energy absorption, etc. There also seems to be some misunderstanding of the interdependence of guard strength and energy absorption, and their combined effect on the guard's ability to limit underride while keeping occupant acceleration forces in a safe range. In this paper, we validated the Finite Element (FE) model of an existing rear impact guard against actual FMVSS 223 tests. We also modified a previously evaluated FE model of a 1990 Ford Taurus by updating its hood geometry and material properties.

Mechanical counter-pressure (MCP) spacesuit designs have been a promising, but elusive alternative to historical and current gas pressurized spacesuit technology since the Apollo program. One of the important potential advantages of the approach is enhanced mobility as a result of reduced bulk and joint torques, but the literature provides essentially no quantitative joint torque data or quantitative analytical support. Decisions on the value of investment in MCP technology and on the direction of technology development are hampered by this lack of information since the perceived mobility advantages are an important factor. An experimental study of a simple mechanical counter-pressure suit (elbow) hinge joint has been performed to provide some test data and analytical background on this issue to support future evaluation of the technology potential and future development efforts.

Analysis of the National Automotive Sampling System (NASS) data reveals that vehicle rollover accidents account for a relatively a small number of accidents, but the associated frequency of serious injury is high compared to frontal or side impact. These data demonstrate the apparently elevated probability of head and neck injury during rollover, with head injury occurring more frequently, injured 4.5 times more frequently than the neck when considering all injuries. Automotive industry researchers have performed numerous rollover tests with instrumented ATD's and have predicted an elevated probability of neck injury with little chance of head injury. This contradicts field data (NASS-CDS) which suggests a high frequency of head injury with little chance of neck injury. This difference may be explained in part, through the different volumes of data presented in the literature.

Rollover crashes are responsible for a significant proportion of traffic fatalities each year, while they represent a relatively small proportion of all motor vehicle collisions. The purpose of this study was to focus on rollover events from an occupant's perspective to understand what type of industry test method, ATD, computer based model, and injury assessment measures are required to provide occupant protection during rollovers. Specific injuries most commonly experienced in rollovers along with the associated injury sources were obtained by review of 1998-2000 NASS-CDS records. These data suggest that models capable of predicting the likelihood of brain injuries, specifically subarachnoid and subdural hemorrhage, are desirable. Ideally, the model should also be capable of predicting the likelihood of rib fractures, lung contusions and shoulder (clavicular and scapular) fractures, and facet, pedicle, and vertebral body fractures in the cervical spine.

A variety of test methodologies currently exist to assess the propensity of a vehicle to roll laterally, the vehicle performance during a rollover event, and the associated risk of injury to the occupant. There are indications as to which tests are appropriate when attempting to replicate rollover events observed in the field. Due to the complexity of a rollover, test repeatability is a concern as well as cost, and field relevance. Since revisions to governmental rollover regulations are currently being considered, an assessment of currently available rollover test methodologies would provide a context to compare the different experimental designs. Additionally, the design of injury prevention strategies such as side air curtains, 4-point belts, etc. will also require the establishment of repeatable, robust, and economical test methods.

Impinging jets are an established technique for obtaining high local heat transfer coefficients between a fluid and a surface. Factors such as jet attachment, surface angle, jet angle, separation distance between jet orifice and surface of impingement, and trajectory influence heat transfer dramatically. In the current study, the specific application of interest is air issuing from the defroster's nozzles of a vehicle and impinging on a glass windshield. The current work is aimed at studying the flow patterns off a vehicle windshield as a result of air issuing from various nozzle configurations. The effects of openings' geometry (circular vs rectangular), number of openings, angle that the windshield makes with the horizontal plane and angle of impinging jet, on windshield heat transfer is examined. An optimal configuration will be recommended for better heat transfer.

Numerous human cadaver impact studies have shown that acute injury to the knee, femoral shaft, and hip may be significantly reduced by increasing the contact area over the anterior surface of the knee. Such impact events are common in frontal crashes when the knee strikes the instrument panel (IP). The cadaveric studies show that the injury threshold of the knee-thigh-hip complex increases as the contact area over the knee is likewise increased. Unfortunately, no prior methodology exists to record the spatial and temporal contact pressure distributions in dummy (or cadaver) experiments. Previous efforts have been limited to the use of pressure sensitive film, which only yields a cumulative record of contact. These studies assumed that the cumulative pressure sensitive film image correlated with the peak load, although this has never been validated.

Prior experimental and field studies have demonstrated an increased risk of upper extremity fracture due the deployment of frontal airbags. The experimental studies provide valuable insight as to likely injury mechanisms; namely, increasing proximity increases the risk of forearm fracture. Still, field data is needed to validate these experimental findings. The available field data has largely been derived from direct case study analysis or a review of government accident statistics. In both cases, the datasets were comprised solely of pre-1995 era vehicles. Such data represents early generation airbag designs and there has been little additional study in this area. In addition, there has been an absence of fracture pattern analyses as a function of airbag deployment and non-deployment. Such an analysis would help elucidate the role of the deploying airbag on upper extremity fracture in the current fleet.

A coupler has been developed to prevent windshield wiper systems from being damaged by excessive loads that can occur when the normal wiping pattern is restricted. The coupler is composed of a pultruded composite rod with injection-molded plastic spherical joints (a.k.a. sockets) attached at either end. The sockets are used to attach the coupler to the crank and rocker of the windshield wiper linkage. Because the loads exerted on a coupler vary in magnitude and direction during a wiping cycle, the joint between the sockets and the pultruded composite rod must be robust. The paradigm for attaching sockets to steel couplers (i.e. over-molding the sockets around holes stamped into the ends of traditional steel couplers) was applied to the pultruded rods, tested, and found to produce inadequate joint strength. This paper details the methodology that was employed to produce and optimize an acceptable means to attach the injection-molded sockets to the pultruded rods.

Large hood mounted plastic trim components are subjected to complex and often extreme loading conditions. Typical loading conditions include solar and thermal cycling, as well as road and powertrain induced vibrations, aero lift and buffeting, and mechanical loads such as car wash. For the above components understanding and classifying the typical loading conditions is an essential and important step in achieving long term quality. This paper discusses different approaches to the design, analysis, development, and testing of plastic trim components. Samples of analysis and test results are presented to demonstrate how to identify and prevent the loss of the part function. Some useful guidelines and practices for addressing thermal expansion, dimensional variation, and redundancy in attachments are also discussed.

Doors inside an automotive HVAC module are essential components to ensure occupant comfort by controlling the cabin temperature and directing the air flow. For temperature control, the function of a door is not only to close/block the airflow path via the door seal that presses against HVAC wall, but also control the amount of hot and cold airflow to maintain cabin temperature. To meet the stringent OEM sealing requirement while maintaining a cost-effective product, a “V-Shape” soft rubber seal is commonly used. However, in certain conditions when the door is in the position other than closed which creates a small gap, this “V-Shape” seal is susceptible to the generation of objectionable whistle noise for the vehicle passengers. This nuisance can easily reduce end-customer satisfaction to the overall HVAC performance.

Numerous studies have documented the implantation of a 6-axis load cell in series with the tibial shaft and a limited number of studies have instrumented the femur for uniaxial load transduction. We are unaware of a single study seeking to instrument both anatomical segments. In addition, while the instrumentation processes have been described in textural and graphical detail, the dimensions and material choices for preparation jigs, potting cups, etc. are typically not given. In the current study, we have reviewed the available literature and have developed a modified preparation and implantation methodology. We also include complete designs appropriate for a reproduction of our process or modification of the methodology by the reader. The robustness of our technique was verified in a companion study in which whole, unembalmed cadavers were subjected to a HYGE frontal sled test without compromise of the instrumentation.

Use of the top tether attachment in three commonly available anchor points provides added restraint of child restraint systems (CRS). Three tether attachment positions were used; floor, behind the head rest (parcel deck) and at the ceiling. The three anchor points are comparable in efficacy while no tether allows increased travel of the anthropomorphic test device (ATD) head. Two series of six tests were conducted at a max speed of 20 mph and peak deceleration of 16 G's using a deceleration sled test apparatus. The first series of tests was conducted at a 90 degree impact angle. On average there is 9% less head travel when using the tether attachment compared to not using the tether attachment, all other conditions begin equal. The second series of tests was conducted at a 73 degree impact angle, there is 15% less head travel when using the tether attachment compared to not using the tether attachment, all other conditions begin equal.

Safety is considered one of the most important parameters when designing a ground vehicle. The adverse effect of weather on a vehicle can lead to a surge in safety issues and accidents. Several safety assistance systems are available in modern vehicles, which are designed to lessen the negative effects of weather hazards. Although these safety systems can intervene during crucial conditions to avoid accidents, driving a vehicle on snowy or icy terrain can still be a challenging task. Road conditions with the least tire-road friction often results in poor vehicle handling, and without any kind of safety system it can lead to mishaps. With the use of Adams Car software and vehicle dynamics modeling, a realistic relationship between the vehicle and road surface may be established. The simulation can be used to have a better understanding of vehicle handling in snowy and icy conditions, tire-ice interaction, and tire modeling.

Numerous studies have documented that lower extremity injury is second only to the head and face in automotive accidents. Such injuries are common because the lower extremity is typically the first point of contact between the occupant and the car interior. Of all lower extremity injuries, the knee is the most common site of trauma. This typically results from high speed contact with the instrument panel which can produce fracture and subfracture (contusions, lacerations, abrasions) level injuries. Current Federal safety guidelines use a bone fracture criterion which is based solely on a peak load. The criterion states that loads exceeding 10 kN will likely result in gross bone fracture. However, cadaver experiments have shown that increased contact area (via padding) over the knee can significantly increase the amount of load that can be tolerated before fracture or subfracture injury.