• Title/Summary/Keyword: Automotive noise

Search Result 672, Processing Time 0.027 seconds

Optimization of the Durability Performance of a 17cc Automotive Compressor (17cc급 자동차용 압축기 내구성능 최적화에 관한 연구)

  • Yang, Yong-Kun;Wu, Yu-Ting;Qin, Zhen;Lyu, Sung-Ki
    • Journal of the Korean Society of Manufacturing Process Engineers
    • /
    • v.20 no.3
    • /
    • pp.68-75
    • /
    • 2021
  • The fuel economy is a key issue for the automotive industry due to environmental concerns. In particular, only 5-20% of the energy generated in a car using an internal combustion engine is used as power, and the remaining energy is dissipated due to friction with other parts. The main components in the reciprocating piston type compressors commonly used in general vehicles include shafts, swash plates, pistons, and cylinders, and severe friction loss occurs due to the contact of these components. Generally, the wear contact is the maximum between the shaft and cylinder and between the piston and swash plate. The friction of these parts may cause quality problems and deteriorate the durability. In this study, to reduce the frictional loss, a prototype with additional coating agents was produced. Moreover, an optimized design was generated, and performance, noise, and durability tests were conducted. A more durable product was successfully obtained.

Filtering Time Optimization in Vehicle Electronic Control Systems Using a Non-Contact Magnetic Sensor and Dual Buffer Structure (차량용 전자 제어 시스템에서 비접촉식 자기장 센서와 이중 버퍼 구조를 이용한 필터링 시간 최적화)

  • Minjung Kim;Daejin Park
    • IEMEK Journal of Embedded Systems and Applications
    • /
    • v.19 no.4
    • /
    • pp.203-210
    • /
    • 2024
  • The automotive industry is transitioning from traditional internal combustion engines to systems powered by motors, batteries, and various electronic control units. Central to this shift is the micro-controller unit, which processes data from various sensors for real-time environmental awareness and control. This paper explores using non-contact magnetic sensors for sensing vehicle inclination as part of a digital twin implementation. Unlike optical or contact sensors, non-contact magnetic sensors offer robust performance in challenging environments, providing consistent and reliable data under varying conditions. To optimize real-time data processing, we propose a double buffer structure to enhance digital signal processing performance in embedded systems. Experiments using a custom sensor-integrated board demonstrate that the double buffer structure with direct memory access-enabled serial peripheral interface significantly reduces data processing time and improves noise reduction filtering. Our results show that the proposed system can greatly enhance the reliability and accuracy of sensor data, crucial for real-time vehicle control systems. In particular, by using the double buffer structure proposed in this paper, it was possible to secure 8.27 times more data compared to raw data, despite performing additional filtering. The techniques outlined have potential applications in various fields, offering enhanced monitoring and optimization capabilities, thus paving the way for more advanced and efficient vehicle control technologies.

Improvement in flow and noise performances of small axial-flow fan for automotive fine dust sensor (차량용 미세먼지 센서용 소형 축류팬의 유동과 소음 성능 개선)

  • Younguk Song;Seo-Yoon Ryu;Cheolung Cheong;Inhiug Lee
    • The Journal of the Acoustical Society of Korea
    • /
    • v.42 no.1
    • /
    • pp.7-15
    • /
    • 2023
  • Recently, as interest in air quality in vehicles increases, the use of fine dust detection sensors for air quality measurement is becoming common. An axial-flow fan is inserted in the fine dust sensor installed in the air conditioning system in the vehicle to prevent dust from sinking directly on the sensor. When the sensor operates, the flow noise caused by the rotation of the axial-flow fan acts as a major noise source of the fine dust sensor. flow noise is recognized as one of the product competitiveness of fine dust sensors. In this study, the noise was gradually reduced at the same flow rate by improving the flow performance of the small axial flow fan. First, a virtual fan performance tester consisting of about 20 million grids was developed to analyze the aerodynamic performance of the target small axial-flow fan. In addition, the flow field was simulated by using compressible Large Eddy Simulation for direct computation of flow noise as well as high-accurate prediction of flow rate. The validity of numerical method are confirmed through the comparison of predicted results with experimental ones. After the effects of pitch angle on flow performance were analyzed using the verified numerical method, the pitch angle was determined to maximize the flow rate. It was found that the flow rate was increased by 8.1 % and noise was reduced by 0.8 dBA when the axial-flow fan with the optimum pitch angle was used.

Dead Time Compensation and Polarity Check of Phase Currents Based on Programmable Low-pass Filter for Automotive Electric Drive Systems (자동차 전동 시스템을 위한 Programmable 저역 통과 필터 기반의 상전류 극성 판단 및 데드타임 보상)

  • Choi, Chinchul;Lee, Kangseok;Lee, Wootaik
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.22 no.6
    • /
    • pp.23-30
    • /
    • 2014
  • This paper proposes a dead time compensation method for an AC motor drive using phase current polarity information which is detected based on a digital programmable low-pass filter (PLPF). The polarity detection using the PLPF is an alternative solution of a conventional method which uses a general low-pass filter (LPF) and hysteresis bands in order to avoid jittering due to noises. The PLPF not only adjusts its cutoff frequency according to the synchronous frequency of AC motors but also eliminates a gain attenuation and phase delay which are main problems of the general LPF. Through the PLPF, a fundamental component signal without gain and phase distortions is extracted from the measured raw current signal with noise. By use of the fundamental component, the polarity of current is effectively detected by reducing the hysteresis band. Finally, the proposed method compensates the dead time effects by adding or subtracting average voltage value to voltage references of the controller according to the detected current polarity information. The proposed compensation method is experimentally verified by compared with the conventional method.

Design of 24-GHz Power Amplifier for Automotive Collision Avoidance Radars (차량 추돌 방지 레이더용 24-GHz 전력 증폭기 설계)

  • Noh, Seok-Ho;Ryu, Jee-Youl
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.20 no.1
    • /
    • pp.117-122
    • /
    • 2016
  • In this paper, we propose 24-GHz CMOS radio frequency (RF) power amplifier for short-range automotive collision avoidance radars. This circuit contains common source stage with inter-stages conjugate matching circuit as a class-A mode amplifier. The proposed circuit is designed using TSMC $0.13-{\mu}m$ mixed signal/RF CMOS process ($f_T/f_{MAX}=120/140GHz$). It operates at the supply voltage of 2V, and it is designed to have high power gain, low insertion loss and low noise figure in the low supply voltage. To reduce total chip area, the circuit used transmission lines instead of the bulky real inductor. The designed CMOS power amplifier showed the smallest chip size of $0.1mm^2$, the lowest power consumption of 40mW, the highest power gain of 26.5dB, the highest saturated output power of 19.2dBm and the highest maximum power-added efficiency of 17.2% as compared to recently reported results.

Radius-Measuring Algorithm for Small Tubes Based on Machine Vision using Fuzzy Searching Method (퍼지탐색을 이용한 머신비전 기반의 소형 튜브 내경측정 알고리즘)

  • Naranbaatar, Erdenesuren;Lee, Sang-Jin;Kim, Hyoung-Seok;Bae, Yong-Hwan;Lee, Byung-Ryong
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.35 no.11
    • /
    • pp.1429-1436
    • /
    • 2011
  • In this paper, a new tube-radius-measuring algorithm has been proposed for effectively measuring the radii of small tubes under severe noise conditions that can also perform well when metal scraps that make it difficult to measure the radius correctly are inside the tube hole. In the algorithm, we adopt a fuzzy searching method that searches for the center of the inner circle by using fuzzy parameters for distance and orientation from the initial search point. The proposed algorithm has been implemented and tested on both synthetic and real-world tube images, and the performance is compared to existing circle-detection algorithms, such as the Hough transform and RANSAC methods, to prove the accuracy and effectiveness of the algorithm. From this comparison, it is concluded that the proposed algorithm has excellent performance in terms of measurement accuracy and computation time.

Active monitoring of pipeline tapered thread connection based on time reversal using piezoceramic transducers

  • Hong, Xiaobin;Song, Gangbing;Ruan, Jiaobiao;Zhang, Zhimin;Wu, Sidong;Liu, Guixiong
    • Smart Structures and Systems
    • /
    • v.18 no.4
    • /
    • pp.643-662
    • /
    • 2016
  • The monitoring of structural integrity of pipeline tapered thread connections is of great significance in terms of safe operation in the industry. In order to detect effectively the loosening degree of tapered thread connection, an active sensing method using piezoceramic transducers was developed based on time reversal technique in this paper. As the piezoeramic transducers can be either as actuators or sensors to generate or detect stress waves, the energy transmission for tapered thread connection was analyzed. Subsequently, the detection principle for tapered thread connection based on time reversal was introduced. Finally, the inherent relationship between the contact area and tightness degree of tapered thread connection for the pipe structural model was investigated. Seven different contact area scenarios were tested. Each scenario was created by loosening connectors ranging from 3 turns to 4.5 turns in the right tapered threads when the contact area in the left tapered threads were 4.5 turns. The experiments were separately conducted with a highly noisy environment and various excitation signal amplitudes. The results show the focused peaks based on time reversal have the monotonously rising trend with the increase of the contact areas of tapered threads within an acceptable monitoring resolution for metal pipes. Compared with the energy method, the proposed time reversal based method to monitor tapered threads loosening demonstrates to be more robust in rejecting noise in Structural Health Monitoring (SHM) applications.

A Simulation Investigation on the Spurious Emission Reduction of the Automotive DC-DC Converter (자동차용 DC-DC 컨버터의 전자파 방사 감소 방법에 대한 시뮬레이션 연구)

  • Chae, Gyoo-Soo
    • Journal of Convergence for Information Technology
    • /
    • v.10 no.8
    • /
    • pp.47-52
    • /
    • 2020
  • In this study, a simulation investigation was conducted on the method of reducing switching noise and spurious emission among design methods for step-down DC-DC converter modules for automotive. A typical 4-layer converter circuit using a PMIC(Power Management Integrated Circuit) chip was presented, and the simulation results of conductive emissions at two input terminals (+, -) and the point between the input filter and the PMIC was performed in the 1.0~5.0MHz band and the 100MHz band. The results for the conducted and radiated emissions in the HF(3~30MHz) and VHF(30-300MHz) bands were presented. It showed an improvement of about 10dB over the bands by routing the output terminal placed on the 3 or 4-layer in the opposite direction to the input terminal. The result of this study is expected to be useful in the design of the DC-DC converter modules in the future because it gives a better improvement compared to the existing methods.

Design of Q-Band LC VCO and Injection Locking Buffer 77 GHz Automotive Radar Sensor (77 GHz 자동차용 레이더 센서 응용을 위한 Q-밴드 LC 전압 제어 발진기와 주입 잠금 버퍼 설계)

  • Choi, Kyu-Jin;Song, Jae-Hoon;Kim, Seong-Kyun;Cui, Chenglin;Nam, Sang-Wook;Kim, Byung-Sung
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.22 no.3
    • /
    • pp.399-405
    • /
    • 2011
  • In this paper, we present the design of Q-band LC VCO and injection locking buffer for 77 GHz automotive radar sensor using 130 nm RF CMOS process. To improve the phase noise characteristic of LC tank, the transmission line is used. The negative resistance by the active device cross-coupled pair of buffer is used for high output power, with or without oscillation of buffer. The measured phase noise is -102 dBc/Hz at 1 MHz offset frequency and tuning range is 34.53~35.07 GHz. The output power is higher than 4.1 dBm over entire tuning range. The fabricated chip size is $510{\times}130\;um^2$. The power consumption of LC VCO is 10.8 mW and injection locking buffer is 50.4 mW from 1.2 V supply.

Evaluation of Design Variables to Improve Sound Radiation and Transmission Loss Performances of a Dash Panel Component of an Automotive Vehicle (방사소음 및 투과소음에 대한 승용차량 대시패널의 설계인자 별 영향도 분석)

  • Yoo, Ji-Woo;Chae, Ki-Sang;Park, Chul-Min;Suh, Jin-Kwan;Lee, Ki-Yong
    • Transactions of the Korean Society for Noise and Vibration Engineering
    • /
    • v.22 no.1
    • /
    • pp.22-28
    • /
    • 2012
  • While a dash panel component, close to passengers, plays a very important role to protect heat and noise from a power train, it is also a main path that transfers vibration energy and eventually radiates acoustic noise into the cavity. Therefore, it is important to provide optimal design schemes incorporating sound packages such as a dash isolation pad and a floor carpet, as well as structures. The present study is the extension of the previous investigation how design variables affect sound radiation, which was carried out using the simple plate and framed system. A novel FE-SEA hybrid simulation model is used for this study. The system taken into account is a dash panel component of a sedan vehicle, which includes front pillars, front side members, a dash panel and corresponding sound packages. Design variables such as panel thicknesses and sound packages are investigated how they are related to two main NVH indexes, sound radiation power(i.e. structure-borne) and sound transmission loss(i.e. air borne). In the viewpoint of obtaining better NVH performance, it is shown that these two indexes do not always result in same tendencies of improvement, which suggests that they should be dealt with independently and are also dependent on frequency regions.