.Advanced Driver Assist System (ADAS) and autonomous vehicle technologies have disrupted the traditional automotive industry with potential to increase safety and optimize the cost of car ownership. Light detection and ranging (LIDAR) sensing, a sensing method that detects objects and maps their distances, is seeing rapid growth and adoption in the industry. However, the sensor requirements and system architecture options continue to evolve. This course will provide the foundation on which to build LIDAR technologies in automotive applications.
Advanced Driver Assist System (ADAS) and autonomous vehicle technologies have disrupted the traditional automotive industry with potential to increase safety and optimize the cost of car ownership. Among the challenges are those of sensing the environment in and around the vehicle. Infrared camera sensing is seeing a rapid growth and adoption in the industry. The applications and illumination architecture options continue to evolve. This course will provide the foundation on which to build near infrared camera technologies for automotive applications.
Every year, the U.S. on average, experiences more than 34,000 traffic deaths and over 5 million vehicle crashes. While the trend in traffic deaths has been generally downward for the past decade, most of this reduction has been the result of optimizing passive occupant crash protection systems such as seatbelts and airbags. Highly automated vehicle's (HAV's) offer the potential to significantly reduce vehicle crashes by perceiving a dangerous situation before the crash has occurred and supporting the human driver with proactive warnings and in some cases active interventions to avoid or mitigate the crash.
The fuel economy of recent small size DI diesel engines has become more and more efficient. However, heat loss is still one of the major factors contributing to a substantial amount of energy loss in engines. In order to a full understanding of the heat loss mechanism from combustion gas to cylinder wall, the effect of hole size and rail pressure under similar injection rate conditions on transient heat flux to the wall were investigated. Using a constant volume vessel with a fixed impingement wall, the study measured the surface heat flux of the wall at the locations of spray flame impingement using three thin-film thermocouple heat-flux sensors. The results showed that the characteristic of local heat flux and soot distribution was almost similar by controlling similar injection rate except for the small nozzle hole size with increasing injection pressure.
In the present work, a relative comparison of addition of water to diesel through emulsion and fumigation methods is explored for reducing oxides of nitrogen (NOx) and smoke emissions in a production small bore diesel engine. The water to diesel ratio was kept the same in both the methods at a lower concentration of 3% by mass to avoid any adverse effects on the engine system components. The experiments were conducted at a rated engine speed of 1500 rpm under varying load conditions. A stable water-diesel emulsion was prepared using a combination of equal proportions (1:1 by volume) of Span 80 and Tween 80. The mixture of Span 80 in diesel and Tween 80 in water was homogenized using an IKA Ultra Turrax homogenizer with tip stator diameter 18mm at 5000 rpm for 2 minutes. The water-in-diesel emulsions thus formulated were kinetically stable and appeared translucent. No phase separation was observed on storage for approximately 105 days.
In the last decade, pollution by particulate matter and its effect on human health has increasingly become the focus of public attention. In order to monitor and evaluate particulate pollution, expensive measuring stations were placed at traffic hotspots and other selected locations. The measuring devices often precisely record the particle concentration, but have disadvantages in mobility and for measurements in large-area due to their size and investment costs. A measurement with high temporal and spatial resolution is not possible with these stations. This paper presents a new type of mobile particulate sensor based on the Plantower PMS 7003 particle sensor. In addition to the Plantower sensor, a rechargeable battery and newly developed control electronics are also installed in the particulate sensor. Due to the small size and the low manufacturing costs of the measuring system, mobile usage in higher quantity is possible.
Despite the increase in public attention to particulate matter emissions since the millennium and the known effects on the human organism, representative predictions on the dispersion of emissions in both urban and rural areas are hardly possible so far. Especially the validation of simulations with measurement results is not possible due to the limited number and high price of certified measuring instruments. Rather, the temporally high-resolution measuring instruments are only sporadically distributed within the city, so that emission dynamics at traffic hotspots, such as traffic jams or intersections, cannot be depicted. Furthermore, due to the small number of certified measuring instruments, fine dust pollution can only be interpolated over long distances. In this paper, first statements about the transport characteristics of particles at a road intersection will be made by using a variety of so-called low-cost particulate matter sensors.
Measuring brake emission is still a challenging non-standardized task. Extensive research is ongoing. Updates of work in progress are presented at SAE Brake Colloquium and PMP meetings. However, open items include how to achieve lower background concentration and how to design the brake enclosure. A low background concentration is essential as brake events are short and some emit in the range of reported background levels. Hence these emissions are difficult to distinguished from the background level. Even more critical, a high background concentration can result in a wrong particle number emissions value, either overestimated, background counted as emissions, or underestimated, background level subtracted, and low emission events no longer detected and counted. However, reducing the background level to less than 100 #/cm³ appeared to be quite challenging.
The frictional behavior of a tribological contact is influenced by the dynamics in the forming boundary layer. Recurring structures, built up through self-organizing effects, were found in various frictional systems. To investigate those phenomena on a macroscopic scale and to better understand dynamical processes such as the formation and decay of contact patches, the first revision of the Wear Debris Investigator (WDI) was introduced in 2017. A friction gap is formed between two coaxial horizontally arranged discs. To mimic the presence of particles, artificial wear dust is fed into the gap. With a camera the formation of the boundary layer is recorded in situ. An implemented normal force and torque sensor enables to recognize correlations between the formed boundary layer and the occurring frictional forces. Numerous measurements revealed an insufficient precision of the previous WDI.
Raising demands towards lightweight design paired with a loss of originally predominant engine noise pose significant challenges for NVH engineers in the automotive industry. From an aeroacoustic point of view, low frequency buffeting ranks among the most frequently encountered issues. The phenomenon typically arises due to structural transmission of aerodynamic wall pressure fluctuations and/or, as indicated in this work, through rear vent excitation. A possible workflow to simulate structure-excited buffeting contains a strongly coupled vibro-acoustic model for structure and interior cavity excited by a spatial pressure distribution obtained from a CFD simulation. In the case of rear vent buffeting no validated workflow has been published yet. While approaches have been made to simulate the problem for a real-car geometry such attempts suffer from tremendous computation costs, meshing effort and lack of flexibility.
Unpredictable faults oriented from ambiguous reasons could occur in an engine of a vehicle. However, there are some symptoms from which an engine is working abnormally before the engine is stalled by faults. In this paper, methods for diagnosis of engine faults by using vibrations are proposed. Through bench tests, to extract features for fault diagnosis, various samples with normal and abnormal conditions are prepared and vibration signals from the block of an engine are measured and analyzed. To consider cost and performance of a sensor, vibrations from a knock sensor signal as well as accelerometers are analyzed. Measured vibration signals are synchronized with signal of the crank position sensor and analyzed to detect which event is involved. Modulation analysis and Hilbert transform are applied to extract features representing the symptoms of engine faults and to indicate when the abnormal event happens, respectively.
As original engine sound is usually not enough to satisfy the driver’s desire for the sporty and fascinating sound, active noise control (ANC) and active sound design (ASD) have been great technologies in automobiles for a long time. However, these technologies which enhance the sound of vehicle using loud speakers or electromagnetic actuators etc. lead to the increase of cost and weight due to the use of external amplifier or external actuators. This paper presents a new technology of generating a target sound by the active control of a permanent magnet synchronous motor (PMSM) which is already mounted in vehicle. Firstly, an algorithm of this technology, called an active sound generation (ASG), is introduced with those signal conversion process, and then the high frequency noise issue and its countermeasure are presented.