论如何在高速路上安全使用轮胎

随着我国汽车工业的发展以及人民生活水平的提高,汽车数量在快速增长,由此带来的汽车行车安全应该引起我们足够的重视。在汽车行驶之前,我们必须要对汽车进行全面检查,特别是对轮胎的状况要有足够了解。在汽车行驶在高速公路的时候,轮胎的状况关系到整个行车安全,如果轮胎使用不当,很容易引发爆胎事故,最终导致车毁人亡,因此,出于安全考虑,我们必须要知道在高速路上如何安全使用轮胎。本文主要介绍了在高速路上发生爆胎事故的主要原因,讨论了如何在高速路上预防爆胎事故的发生,探讨了高速路上一旦发生爆胎事故应如何处理。     

夏季轮胎使用调查

夏天是汽车轮胎相关安全事故高发的季节,因为路面温度高,胎内气体膨胀等原因,高速行驶中的轮胎容易发生爆胎事故,直接影响行车安全。如果平时不注意保养,或者是购买了劣质的轮胎,就会给车辆的安全埋下巨大的隐患。前不久,在京承高速上就上演了惊险的一幕。     

航空结构轮胎爆破喷流载荷下的结构损伤分析及试验研究

飞机在飞行中，起落架收起后出现的爆胎是由于先前的轮胎损伤而产生的，在轮胎的外露表面上任何一处都有可能发生。为研究舱内轮胎爆破的喷流载荷对飞机结构的影响，采用了一种可以反映瞬时气流场压力分布的工程拟合法，建立了工程计算模型。利用该计算模型，观察典型大尺寸结构在瞬时喷流载荷下的动力学响应过程，得到了结构损伤。结果表明：爆破点附近结构弹性变形很大，刚度最大的结构(如缘条)是危险部位；舱内轮胎爆破对结构破坏更严酷；该模型的计算结果与试验数据吻合较好，能够正确预测喷流载荷的压力场分布和结构的动态响应过程；该方法为航空结构的抗轮胎爆破冲击设计与损伤分析提供了一种可靠的手段。     

基于ZigBee无线网络技术的TPMS研究

研究一种基于ZigBee技术的TPMS系统,该系统可随时测量轮胎的压力、温度、加速度及电池电压,确定故障轮胎并及时报警。     

基于压力传感器的水下弹丸定位系统

水下弹丸速度的测量一般是测量弹丸的速度大小,而对弹丸的位置、飞行方向关注较少.本文设计了一种可以检测水下弹丸位置、飞行方向、速度大小的弹丸定位系统.该系统通过在弹丸预射轨迹附近布置多个压力传感器,采集弹丸通过传感器附近时的峰值压力以及峰值压力的发生时刻,通过公式可以对弹丸在传感器附近的位置信息、速度大小和飞行方向进行解算,从而实现对弹丸的多点定位.仿真结果表明,该系统可以通过压力传感器得到的峰值压力和峰值压力的发生时刻实现对弹丸的水下定位.     

多通道高精度应变测量技术研究

设计了一种新型多通道应变测量系统 ,该系统能够消除测量环节中的运算放大器、A D转换器及电桥供电电源漂移的影响 ,具有极高的测量精度和稳定性。该测量原理不仅可应用于应变测量系统 ,还可应用于温度、压力等测量系统中 ,具有非常广泛的使用范围 ,文中还分析了该系统的特性、修正系数和实验结论     

R32涡旋压缩机两相喷射制冷系统的设计与控制

R32涡旋压缩机存在排气温度过高的问题,利用两相制冷剂喷射可降低排气温度同时提升性能。基于经济器系统,提出了R32涡旋压缩机的两相喷射制冷系统,利用模拟仿真对其设计和控制方法进行了研究。从压缩机的角度,分析了喷射口等效直径对两相喷射压缩机性能的影响,并指出了两相喷射时喷射压力和喷射干度的优化方向。通过对两相喷射系统的模拟分析,在系统层面上对中间换热器的换热能力进行了优化配置和对中间喷射压力进行了优化控制,并提出根据排气温度来确定最优中间压力的方法,即将排气温度控制为135℃对应的中间压力为最优中间压力。经过优化后的两相喷射系统,不仅解决了排气温度过高的问题,而且能够提升制冷量7.1%~11.4%,提升COP 2.6%~6.2%。     

ZigBee技术的汽车胎压监测系统设计

针对目前直接主动式汽车胎压监测系统处理器与射频芯片分开设计、433 MHz无线频率造成的系统体积大、无组网、抗干扰能力弱等关键技术问题,设计了一种基于无线传感器网络的直接主动式汽车胎压监测系统.其中系统采用ZigBee首款SOC单芯片CC2430,无线通信频率为2.4 GHz.软件设计上改进了ZigBee通讯协议CSMA/CA机制,这样既能有效避免各轮胎监测节点发送数据的冲突,又能降低系统能耗、延长网络寿命.该系统能够实时自动监测轮胎内部压力、温度等状态信息,从而有效地保障了汽车行驶安全.     

基于STM32的足底压力测量系统

人体的足底压力研究在临床医学和康复治疗方面具有重要意义。在该背景下,本文以运动人体为对象,依托人体运动时的压力特点制作了鞋垫式足底压力采集模块,该模块能够根据人体运动习惯进行压力采集。在此基础上,采用STM32微处理器、足底压力传感器、信号调理模块,无线通信模块等装置设计了足底压力测量系统。整个测量系统,能够实现对足底压力的自动采集、处理和传输,同时对足底压力信息的实时显示和存储。可为足底压力测量和分析提供进一步的参考。     

一种新型轮胎的设计与分析

 为了提高轮胎的防刺破、防爆胎和安全防弹性能,减轻重量,提出一种用于某型轮式特种车辆的无气轮胎,探索出一种新的轮胎设计方法.通过力学分析,建立了轮胎的结构模型,并利用有限元分析软件ANSYS对轮胎进行与地面的非线性大变形接触分析,获得车辆静态承载时车轮的受力与变形关系及应力分布情况,得到一些重要的设计参数,从而可以合理选材,改善胎体结构,优化设计方案.通过变形和接触力的关系得到轮胎的径向刚度曲线,为下一步的仿真分析提供重要的刚度参数.     

航空轮胎爆破气流场测试方法

航空轮胎对于飞机安全性有着重要的意义,若发生轮胎爆破,起落架舱内的设备及管路系统会发生破坏从而引发重大航空事故,因此在设计阶段需要对起落架舱内结构进行优化设计,而飞机轮胎爆破过程中气流场分布规律显得至关重要。基于国产某定型客机进行轮胎爆破空气喷流模式压力场测试,采用翼型支架对气压传感器进行支撑。通过实验发现,采用翼型截面支架安装高频动压传感器可得到有效的气流场压力,实验结果得到了中国民用航空局适航审查认证。轮胎爆破是瞬时释放巨大能量的过程,对周围结构的破坏是灾难性的,因此在设计中必须考虑轮胎爆破的影响。     

A System to Measure Both Inner and Outer Car Tire Temperatures “in situ”

In the paper, a system for the complex analysis of the internal and external tire temperatures and pressure of sporty tires is presented. Tests were performed on the test circuit of a tire producer. The CTPA 05 measuring system (complex temperature-pressure analyzer) enables simultaneous measurements of the internal temperature and pressure in a passenger or sports tire. The experimentalist determines that the CTPA 05 can be used to measure independently the external temperature of the overcoat on the front wheel driving tires at three points. Measurements of both the internal tire temperature and pressure, as well as of the external tire temperature, are collected together with GPS (global position system) data. The system of measurement is fully automatic and contactless. The obtained results are in very good agreement with those obtained by independent methods.     

轮胎振动特性实验研究

利用振动实验模态分析的方法,建立了自由悬置状态下轮胎的振动特性模态测试与分析系统,通过轮胎径向激振测试信号的数据处理与分析,提取了各阶的频率及其径向模态振型,分析了轮胎的模态参数随充气压力变化的规律,为实验方法的研究和轮胎结构设计及车辆的动力性能分析提供指导。     

Effect of consecutive driving on accident risk: A comparison between passenger and freight train driving

This study combined driver-responsible accidents with on-board driving hours to examine the effect of consecutive driving on the accident risk of train operations. The data collected from the Taiwan Railway Administration for the period 1996–2006 was used to compute accident rates for varied accumulated driving hours for passenger and freight trains. The results showed that accident risk grew with increased consecutive driving hours for both passenger and freight trains, and doubled that of the first hour after four consecutive hours of driving. Additional accident risk was found for freight trains during the first hour due to required shunting in the marshalling yards where there are complex track layouts and semi-automatic traffic controls. Also, accident risk for train driving increased more quickly over consecutive driving hours than for automobile driving, and accumulated fatigue caused by high working pressure and monotony of the working environment are considered to be the part of the reason. To prevent human errors accidents, enhancing safety equipment, driver training programs, and establishing a sound auditing system are suggested and discussed.     

Optimal use of warning signs in traffic

The aim of the paper is to develop a model of drivers’ behaviour particularly designed to analyse the safety and total driving cost implications of warning sign installations. One special feature of the model is that it makes a clear distinction between drivers’ perceived risk values at certain speeds and their respective objective values. When focusing on a certain stretch of road only, the paper concludes that warning signs will increase safety and probably reduce total objective driving costs; that is the sum of time costs and objective expected accident costs. Since drivers’ speed will reduce implying higher time costs per distance, the reduction in total objective driving costs will be lower than the reductions in accident costs. The analysis is then extended to comprise the whole road system and using warning signs prior to curves as an example. Besides the driving conditions in different curves, the analysis shows that the optimal number of signs is dependent on the road authorities’ objectives for road traffic and on how drivers form their risk perceptions. Generally speaking, simulations indicate that the safety and economic benefits of warning sign installation are not very high. When considering the whole road system, warning signs seem, however, to have a greater positive impact on total driving costs than on accident costs.     

Influence of drivers' comprehension of posted signs on their safety related characteristics

The paper studies the relationship between drivers' understanding of posted signs in three of the Gulf Cooperation Council (GCC) states, Bahrain, Qatar and the United Arab Emirates (UAE), and some of their safety related characteristics. These characteristics are driving experience, accident involvement, experience per accident, citations received in the last 3 years on speed limit violations, and seat belt usage. A total of 28 posted signs were investigated. These were categorized as warning and regulatory. To achieve the above goals a questionnaire, specially prepared to collect the necessary data, was distributed to over 6000 drivers in the three states. Over 2820 (47%) responded back. Comprehension of posted signs for drivers with high years of driving experience proved to be significantly better than those with lesser experience. However, the results revealed no significant influence on their accident involvements, even when the effect of age is incorporated; experience per accident ratios, or speed citations. Further, the seat belt usage is also found to increase with understanding of posted signs.     

滚动汽车轮胎自激振动仿真及其影响因素分析

以高速行驶汽车产生的轮胎周向多边形磨损现象为背景,通过建立轮胎的有限元模型以及轮胎-路面的LuGre摩擦模型实现了汽车轮胎高速滚动过程有限元模型的建立,应用该模型进行了轮胎侧向自激振动的仿真分析及影响因素研究。仿真结果表明滚动汽车轮胎在一定条件下确实出现了侧向自激振动现象,它也是造成轮胎多边形磨损的原因之一。参数灵敏度分析表明：轮胎侧向自激振动随车速的增加先增加后减小,车速过低或过高时均不能形成自激振动;前束角与外倾角对自激振动的影响与 车速相似,两者都存在一个峰值点;另外,大载荷条件下,胎面自激振动会比较剧烈,轮胎的多边形磨损也比较严重。因此,为避免产生轮胎自激振动,减少轮胎多边形磨损,要将设计参数以及使用工况控制在合适的范围内     

Risk-based reconfiguration of safety monitoring system using dynamic Bayesian network

To prevent an abnormal event from leading to an accident, the role of its safety monitoring system is very important. The safety monitoring system detects symptoms of an abnormal event to mitigate its effect at its early stage. As the operation time passes by, the sensor reliability decreases, which implies that the decision criteria of the safety monitoring system should be modified depending on the sensor reliability as well as the system reliability. This paper presents a framework for the decision criteria (or diagnosis logic) of the safety monitoring system. The logic can be dynamically modified based on sensor output data monitored at regular intervals to minimize the expected loss caused by two types of safety monitoring system failure events: failed-dangerous (FD) and failed-safe (FS). The former corresponds to no response under an abnormal system condition, while the latter implies a spurious activation under a normal system condition. Dynamic Bayesian network theory can be applied to modeling the entire system behavior composed of the system and its safety monitoring system. Using the estimated state probabilities, the optimal decision criterion is given to obtain the optimal diagnosis logic. An illustrative example of a three-sensor system shows the merits and characteristics of the proposed method, where the reasonable interpretation of sensor data can be obtained.     

基于胎压的静态载重测量技术研究

研究了车辆胎压与载重的相关机理,通过测量轮胎内的气压变化间接测出汽车载重。对载重与受力模型进行了分析,并通过测量实验以及误差分析验证了所提出的模型的有效性和实用性。依据提出的测量方法,设计了一种基于胎压的新型数字式便携载重测量仪。该测量仪主要由便携式控制显示终端和压力变送器组成。实验测试结果表明,该测量仪测量精度较高、成本低、体积小、携带方便,适用于各种轮胎车辆的载重测量。     

Asymmetric relationship between driving and safety skills

We hypothesized that the combination of self reported high ratings of driving skills and low ratings of safety skills creates a serious risk for road accident involvement. This study was aimed at investigating the asymmetric interplay between driving and safety skills among Turkish drivers (N=785) using the Driving Skills Inventory [Lajunen, T., Summala, H., 1995. Driver experience, personality, and skill and safety motive dimensions in drivers' self-assessments. Pers. Indiv. Differ. 19, 307-318]. The assumed asymmetric interactions were tested on a number of outcome variables representing risky driving using moderated regression analyses. The results revealed that driving skills moderated the effects of safety skills on six out of the eight outcome variables including the number of accidents, tickets, overtaking tendencies, speed on motorways, and aggressive driving style. Results suggested that high levels of safety skills buffer the negative effect of overconfidence resulting from exaggerated ratings of self-reported driving skills.