Browse Topic: Manufacturing
This specification covers a corrosion- and heat-resistant nickel alloy in the form of bars, forgings, flash-welded rings, and stock for forging or flash-welded rings.
This SAE Aerospace Standard (AS) provides requirements for design and installation of aircraft jacking pad adapters and the mating jack socket interface to permit use of standard jacking equipment to be used in civil and military transport aircraft. The adapter defined herein shall be the key interface between the aircraft and the aircraft jack(s).
This paper presents an analytical approach for identifying suspension kingpin alignment parameters based on screw axis theorem and differential calculation model. The suspension kingpin caster and inclination alignment parameters can produce additional tire force, which affects vehicle handling dynamics. In wheel steering process, the multi-link suspension control arms lead to movement of the imaginary kingpin, which can cause change in suspension kingpin alignment parameters. According to the structure mechanism of commercial vehicle multi-link independent suspension, the kinematics characteristics of imaginary kingpin were analyzed based on the screw axis theorem. The angular velocity and translation velocity vectors were calculated. In order to avoid the influence of bushing deformation, the unique differential identification model was established to evaluate the suspension kingpin alignment parameters, and the identification results were compared with the ADAMS/Car data. The
Over the past 30 years concerns about noise & vibration have become more critical in the design and manufacture of the automobile. Tools, both in physical testing and computer aided engineering have and continue to develop permitting more refined designs. Today’s customer can be very discerning when it comes to vehicle noises and vibrations. However, this is not a new concern for automotive customers or manufactures. This paper highlights the drive from automotive manufacturers to promote quiet, smooth and vibrationless operation of their products as well as some of the advances in vehicle component design over the past 100+ years. This is not an exhaustive study, but rather the intent is to bring to light the long history of noise and vibration in the automotive industry and its importance to the customers even in the infancy of the auto industry.
As the adoption of Electric Vehicles (EV) and Plug-in Hybrid Electric Vehicles (PHEV) continues to rise, more individuals are encountering these quieter vehicles in their daily lives. While topics such as propulsion sound via Active Sound Design (ASD) and bystander safety through Acoustic Vehicle Alerting Systems (AVAS) have been extensively discussed, charging noise remains relatively unexplored. Most EV/PHEV owners charge their vehicles at home, typically overnight, leading to a lack of awareness about charging noise. However, those who have charged their cars overnight often report a variety of sounds emanating from the vehicle and the electric vehicle supply equipment (EVSE). This paper presents data from several production EVs measured during their normal charging cycles. Binaural recordings made inside and outside the vehicles are analyzed using psychoacoustic metrics to identify sounds that may concern EV/PHEV owners or their neighbors.
The ported shroud casing treatment for turbocharger compressors is desirable for mitigating broadband/whoosh noise and enhancing boost pressures at low to mid flow rates. Yet, it is accompanied by elevated narrowband noise at the blade-pass frequency (BPF). Compressor BPF noise occurs at high frequencies where wave propagation is often multi-dimensional, rendering traditional planar wave silencers invalid. An earlier work introduced a novel reflective high-frequency silencer (baseline) targeting BPF noise in the 8-12 kHz range using an “acoustic straightener” that promoted planar wave propagation along arrays of quarter-wave resonators (QWRs). The design, however, faced challenges with high-amplitude tonal noise generation at specific flow conditions due to flow-acoustic coupling at the opening of the QWRs, thereby compromising the noise attenuation. The current study explores two QWR interface geometries that weaken the coupling, including linear and saw-tooth ramps on the upstream
For years the NVH community has known that openings in the dash sheet metal, such as holes to pass wire harnesses through, creates an acoustical weak point that limits the potential noise reduction of the dash insulation system. These pass-throughs can also be a source of water leaks into the vehicle’s interior. With internal combustion engines and now electric inverter power plants generating significant high frequency sound, the need to seal this area is vital. By molding a lightweight barrier that draws through the fiber/absorber interior decoupler and dash sheet metal which mates to a secondary seal molded into an outer engine dash decoupler, the two opposing molded barriers meet in the engine compartment and compress together forming a seal around the wire harness. This male/female molded seal replaces the conventional snap in grommet and eliminates noise/water leaks. The system Sound Transmission Loss (STL) is equivalent to similarly insulated sheet metal with no holes
This article follows a companion article [1] presented at the SAE NVC 2021, in which a new system for the measurement on small samples of the normal-incidence Insertion Loss (IL) of multilayers used for the manufacturing of automotive sound package parts was first introduced. In addition to simplifying the evaluation of the sound-insulation of multi-layers used to produce sound-package components, the system aims at overcoming the limitations of the test procedure based on the ASTM E2611 standard. In this article, the latter point is demonstrated by comparing the insertion loss results obtained with the new system with those obtained with the test procedure based on the ASTM E2611 standard on a few multilayers commonly used for the manufacturing of automotive sound package parts. Results indicate that the data obtained by means of the newly developed system are more meaningful, practically usable and less prone to edge-effects, compared to those obtained according to the ASTM E2611
In the era of Industry 4.0, the maintenance of factory equipment is evolving with new systems using predictive or prescriptive methods. These methods leverage condition monitoring through digital twins, Artificial Intelligence, and machine learning techniques to detect early signs of faults, types of faults, locations of faults, etc. Bearings and gears are among the most common components, and cracking, misalignment, rubbing, and bowing are the most common failure modes in high-speed rotating machinery. In the present work, an end-to-end automated machine learning-based condition monitoring algorithm is developed for predicting and classifying internal gear and bearing faults using external vibration sensors. A digital twin model of the entire rotating system, consisting of the gears, bearings, shafts, and housing, was developed as a co-simulation between MSC ADAMS (dynamic simulation tool) and MATLAB (Mathematical tool). The gear and bearing models were developed mathematically, while
This paper discusses a systematic process that was developed to evaluate the acoustic performance of a production dash system. In this case it is for an electric vehicle application. The production dash panel was tested under different configurations to understand the importance of passthroughs in the acoustics of the system. Results show that often the performance of the passthroughs strongly affects the overall performance of the dash system and this may become the limiting factor to increase the system sound transmission loss. To understand the acoustic strength of different passthroughs and their effects on the overall system, the dash with passthroughs underwent extensive testing. Subsequently, a test procedure using flat panels was developed to quantify the performance of individual passthroughs on a part level. This data can be used by the OEM to develop STL targets that can be considered in the grommet design early in the vehicle development process.
Large eddy simulations (LES) of two HVAC duct configurations at different vent blade angles are performed with the GPU-accelerated low-Mach (Helmholtz) solver for comparison with aeroacoustics measurements conducted at Toyota Motor Europe facilities. The sound pressure level (SPL) at four near-field experimental microphones are predicted both directly in the simulation by recording the LES pressure time history at the microphone locations, and through the use of a frequency-domain Ffowcs Williams-Hawking (FW-H) formulation. The A-weighted 1/3 octave band delta SPL between the two vent blades angle configurations is also computed and compared to experimental data. Overall, the simulations capture the experimental trend of increased radiated noise with the rotated vent blades, and both LES and FW-H spectra show good agreement with the measurements over most of the frequency range of interest, up to 5,000Hz. For the present O(30) million cell mesh and relatively long noise data collection
There is an increasing effort to reduce noise pollution across different industries worldwide. From a transportation standpoint, pass-by regulations aim to achieve this and have been implementing increasingly stricter emissions limits. Testing according to these standards is a requirement for homologation, but does little to help manufacturers understand why their vehicles may be failing to meet limits. Using a developed methodology such as Pass-by Source Path Contribution (SPC, also known as TPA) allows for identification of dominant contributors to the pass-by receivers along with corresponding acoustic source strengths. This approach is commonly used for passenger vehicles, but can be impractical for off-highway applications, where vehicles are often too large for most pass-by-suitable chassis dynamometers. A hybrid approach is thereby needed, where the same techniques and instrumentation used in the indoor test are applied to scenarios in an outdoor environment. This allows for
The segment manipulator machine, a large custom-built apparatus, is used for assembling and disassembling heavy tooling, specifically carbon fiber forms. This complex yet slow-moving machine had been in service for nineteen years, with many control components becoming obsolete and difficult to replace. The customer engaged Electroimpact to upgrade the machine using the latest state-of-the-art controls, aiming to extend the system's operational life by at least another two decades. The program from the previous control system could not be reused, necessitating a complete overhaul.
Climate-neutral aviation requires resource-efficient composite manufacturing technologies and solutions for the reuse of carbon fibers (CF). In this context, thermoplastic composites (TPC) can make a strong contribution. Thermoforming of TPC is an efficient and established process for aerospace components. Its efficiency could be further increased by integration of joining processes, which would otherwise be separate processes requiring additional time and equipment. In this work, an integrative two-step thermoforming process for hollow box structures is presented. The starting point are two organosheets, i.e. fiber-reinforced thermoplastic sheets. First, one of the organosheets, intended for the bottom skin of the uplift structure, is thermoformed. After cooling, the press opens, the organosheet remains in the press and an infrared heater is pivoted in, to locally heat up just the joining area. Meanwhile, a second organosheet, intended for the top skin, is heated and thermoformed and
This SAE Aerospace Standard (AS) establishes minimum requirements for eddy current inspection of circular holes in nonferrous, metallic, low conductivity (less than 5% IACS) aircraft engine hardware with fasteners removed. The inspection is intended to be performed at maintenance and overhaul facilities on engine run hardware.
The mass production of conventional silicon chips relies on a successful business model with large “semiconductor fabrication plants” or “foundries.” New research by KU Leuven and imec shows that this “foundry” model can also be applied to the field of flexible, thin-film electronics. Adopting this approach would give innovation in the field a huge boost.
In the future, autonomous drones could be used to shuttle inventory between large warehouses. A drone might fly into a semi-dark structure the size of several football fields, zipping along hundreds of identical aisles before docking at the precise spot where its shipment is needed.
As a result of advancements to the Industrial Internet of Things (IIoT), companies across the globe are realizing the potential of smart manufacturing and connected business models. In fact, IoT connections are projected to more than double over the coming years: from 18 billion dollars in 2024 to 39.6 billion by 2033.
Machining metal has its challenges as many shops will attest, but machining glass is another matter – one that Dan Bukaty Jr., President of Precision Glass & Optics (PG&O) is well schooled in. Mr. Bukaty and his 35-person shop manufacture high-end precision glass optics for customers such as IMAX, Intuitive Surgical, Boeing and NASA, to name a few. The products PG&O make can range from the ordinary to the extraterrestrial, such as mirrors that it fabricated for the Hobby–Eberly Telescope to measure dark energy in outer space.
In February, the Joint Interagency Field Experimentation (JIFX) team at the Naval Postgraduate School (NPS) executed another highly collaborative week of rapid prototyping and defense demonstrations with dozens of emerging technology companies. Conducted alongside NPS’ operationally experienced warfighter-students, the event is a win-win providing insight to accelerate potential dual-use applications.
MEMS is a more complex technology than traditional semiconductors. They are 3D structures with moving parts, making them much more difficult to fabricate. If you’re designing a semiconductor, you may be able to take advantage of an existing process development kit (PDK), which your foundry can provide to you. There is no equivalent approach in MEMS. It’s a “one process, one product” paradigm that requires a high level of customization. That takes time, money, and resources.
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