• Journal of the Korean Society for Precision Engineering
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• v.11 no.6
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• pp.98-108
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• 1994

An assessment of a mathematical method of synthesing tire tread pitch noise spectra is studied. The method is based on the summation of phasors and the calculated spectra are conveniently generated as computer printout in the form of bar graph. The technique, its usefulness, its limitations and the implications of using such a model are discussed. This paper presents a basic study on optimum pitch arrangement for prediction and control of tire tread pitch noise in constraint condition relatied with tire properties, thus enabling optimum tread pitch arrangements to be determined at the design stage, by application of old tire tread pitch simulation.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2011.04a
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• pp.361-364
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• 2011

In this paper, This work demonstrates a experimental evaluation for vehicle road noise NVH performance from the component-level NVH measurements of Tire. The power unit noise from tire emitted by cars has been reduced. It has been found that tire noise dominates noise produced by the power train when vehicles are driven at high constant speed. Therefore tire pattern noise is affected by pattern and vehicle and transmission loss. Tire noise mechanism is generated by several mechanisms. The sound of tire can propagate either through the air or through the structure of vehicle. Pattern noise is the result of pressure variations through the air to the interior side of vehicle. Especially, smooth asphalt, the periodicity of tread design, groove depth is important factor, which have an influence on the reduction of tire pattern noise.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.14 no.6
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• pp.68-73
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• 2005

Tire manufactures have dealt with noise problem by varying the pitch of the tread. The various formulas for the variations are generally determined differently, however. Often these variations are based on a combination of trial and error, intuition, and economics. Some manufactures have models and analogs to test tread patterns and their variations. These efforts, however practical, do not determine the best variation beforehand or guarantee the best results. For this reason it was felt that a general mathematical approach fur determining the best variation was needed. Moreover, the method should be completely general, easy to use, and sufficiently accurate. This paper discusses a mathematical method called Mechanical Frequency Modulation(MFM) which meets the above requirements. Thus, MFM pertains to computing an irregular time sequence of events so that the resulting excitation spectrum is shaped to a preferred form. The first part of this paper treats the theoretical basis for computing an optimum variation ; the second part discusses experimental results and simulation program which corroborate the theory.

• The Journal of the Acoustical Society of Korea
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• v.12 no.4
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• pp.39-46
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• 1993

조화집중이동하중을 받는 무한보에서의 음향방사에 대한 연구는 선박, 비행기, 타이어 트레드 밴느 등과 같은 계의 설계시 계의 구조물로부터 발생하는 소음에 대한 해결방안을 제시해 준다. 구조물 표면에 발생하는 음향파워는 svktnqusghks방법을 이용하여 보의 전길이에 분포된 음향 인텐시티를 적분하여 구한다. 보의 표면에서 발생하는 음향파원는 미하수, 장력, 감쇠계수, 기초강성계수, 그리고 파수비에 의해서 결정된다. 각 인자에 따른 음향파워에 대한 정성적인 분석을 수행하기 위해 심프슨 적분방법을 이용하여 수치적분을 하였다. 무한보에 작용하는 유체하중에 3다라 진동에너지가 음향에너지로 변환되는 비율이 달라진다. 밀도가 큰 유체는 등가감쇠로 작용하여 보로부터 방사된 음향에너지는 빠르게 감소된다. 하중의 이동에 의하여 도플러이동효과가 발생하여 무한보의 공진부근에서의 음향파워 파크가 분리되고 보의 기초감쇠의 영향으로 음향에너지는 감소된다.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.10
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• pp.2142-2149
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• 2002

Contacting with ground in the post-card area size only, tire supports entire automobile weight. As well, it characterizes most of automobile running performance. Among the design parameters, the carcass contour becomes a key design factor. This paper deals with the time-effective optimal design of tire crown contour in order to improve the tire wear performance by employing a back-propagation neural network model.

• Elastomers and Composites
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• v.11 no.1
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• pp.63-73
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• 1976

에너지 위기후(危機後) 천연자원(天然資源)이 점차로 고갈(枯渴)되여 가고 있는 요즈음 고무산업(産業)에도 이의 여파(餘波)로 몇가지 영향(影響)을 받고 있다. 한 예(例)로 일반적(一般的)으로 널리 사용(使用)되고 있는 23.5% 스티렌 함량(含量)의 SBR제조(製造)에 있어 값싼 부타디엔 및 스티렌 단량체(單量體)를 만들기에는 세계적(世界的) 자원부족(資源不足)으로 인(因)하여 심각(深刻)한 위치(位置)에 놓여있어 장차(長次) 안가(安價)이며 충분(充分)한 량(量)의 합성(合成)고무를 공급(供給)하기에는 SBR과 다른 고무와의 부분적(部分的) 또는 완전(完全)히 다른 합성(合成)고무로 대치 사용함이 타당(妥當)할 것이다. 확범위(擴範圍)한 실험(實驗)끝에 $50\sim55%$ vinyl함량(含量)의 폴리부타디엔 고무가 제조(製造)되였는데 이것은, 자동차용 트레드 부분과 wet skid resistance애 많이 이용(利用)되고 있는 유화(乳化) 또는 용액중합(溶液重合)의 SBR과 매우 유사한 물리적(物理的) 특성(特性)을 나타낸다. 그리고 $45\sim50%$ vinyl함량 폴리부타디엔 고무는 오히려 SBR보다 내마모와 crack growth가 더 좋음을 알았다. 45% vinyl함량 폴리부타디엔 고무와 SBR, cis-플리부타디엔 고무(30/35/35)의 3성분(成分) 혼합체(混合體)는 65/35비율(比率)의 SBR/cis-폴리부타디엔 고무보다 트레드의 마모성이나 미끄럼성이 더 좋았으며 또한 45/20/35 비율(比率)의 혼합체(混合體)도 역시 내 마모성이 좋은 것으로 나타났다. 이와같은 medium vinyl 폴리부타디엔 고무는 SBR로 이용(利用)되고있는 (非)타이어 산어(産業)에서도 SBR대신 단독(單獨) 또는 일부분(一部分) SBR과 혼합(混合)해서 사용(使用)할 수 있다. medium vinyl폴리부타디엔 고무는 낮은 발열성(發熱性)(heat build-up) 그리고 내(耐)빵구성(性)이 우수(優秀)하며 SBR과 유사(類似)한 물리적(物理的) 특성(特性)을 가지고 있으므로 스티렌의 생산(生産)이 활발(活發)해지고 값이 저겸(低謙)하드라도 위와같은 장점(長點) 때문에 장차(長次) 계속 사용(使用)될 것이며 더욱더 개발(開發)될 것이다.

• Journal of the Korean Society of Industry Convergence
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• v.23 no.2_2
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• pp.163-171
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• 2020

The condition of tire tread is a key parameter closely related to the driving safety of a vehicle, which affects the contact force of the tire for braking, accelerating and cornering. The major factor influencing the contact force is tread wear, and the more tire tread wears out, the higher risk of losing control of a vehicle exits. The tire tread condition is generally checked by visual inspection that can be easily forgotten. In this paper, we propose the intelligent tire (iTire) system that consists of an acceleration sensor, a wireless signal transmission unit and a tread classifier. In addition, we also presents classification algorithm that transforms the acceleration signal into the frequency domain and extracts the features of several frequency bands as inputs to an artificial neural network. The artificial neural network for classifying tire wear was designed with an Multiple Layer Perceptron (MLP) model. Experiments showed that tread wear classification accuracy was over 80%.

• Journal of the Korean Society of Industry Convergence
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• v.2 no.1
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• pp.69-75
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• 1999

Intending to develop a new rubber curing process using only microwave, the both the characteristics of cure and the mechanical properties of rubbers for the tire tread, for which a green styrene-butadiene compounds had been cured with 2.45 GHz microwave, have been compared with those of the custom thermal cured rubber. The unintentional hot spot formation in the compound during the microwave curing has not found where the compound has a microwave absorbing ceramic powders in 4.18 weight percents and the supplying voltage has been adjusted to 90 volts. The new microwave process accomplished preheating to 418K in a quarter of the thermal cure time. The average tensile strength of the microwave-cured rubber indicating $190kg/cm^3$ was compatible to that of the thermal cure. In conclusion, the new microwave cure had approved to be applicable in a commercial plant.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.15 no.2 s.95
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• pp.135-147
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• 2005

As automobile technology advances, a smoother ride with less noise is desired. In order to achieve these purposes, a study on the vibration and noise produced by a moving automobile was carried out and a model for tire vibration characteristics which influence the ride performance was developed. The model was verified through simulations and experiments. The developed model was then applied to a half car model and automobile vibrations were analyzed. The effects of tire design parameters on the automobile vibration energy were investigated. The results from laboratory and field tests confirm the validity of the analytical model. The 17-DOF half-car model was built to analyze automobile vibration. The characteristics of the nonlinear model for a shock absorber were applied to this model. The results from the present 17-DOF half car model incorporating the analytical tire model with tire design parameters, were compared with the 5-DOF half car model where the tire was modeled with linear springs. The results of the 17-DOF model are close to the experimental results. Using the 17-DOF model, the influence of tire design parameter were considered. According to the analysis results, the vibrations at seat/body/wheel were predicted by simulation and experiment.

• Journal of the Korean Society of Mechanical Technology
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• v.13 no.4
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• pp.77-84
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• 2011

Tire manufactures have dealt with noise problem by varying the pitch of the tread. The various formulas for the variations are generally determined differently, however. Often these variations are based on a combination of trial and error, intuition, and economics. Some manufactures have models and analogs to test tread patterns and their variations. These efforts, however practical, do not determine the best variation beforehand or guarantee the best results. For this reason it was felt that a general mathematical approach for determining the best variation was needed. Moreover, the method should be completely general, easy to use, and sufficiently accurate. This paper discusses a mathematical method called Mechanical Frequency Modulation(MFM) which meets the above requirements. Thus, MFM pertains to computing an irregular time sequence of events so that the resulting excitation spectrum is shaped to a preferred form. The first part of this paper treats the theoretical basis for computing an optimum variation ; the second part discusses experimental results and simulation program which corroborate the theory.