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Tire Pressure Monitoring Systems (TPMS) are electronic wireless systems that monitor and report air pressure inside pneumatic tires in real time. An example of a TPMS module integrated with the valve stem and showing the typical tire mounting location is shown in Figure 1. For their safety and fuel economy benefits, starting with the mid-2000's, active TPMS were mandated on many vehicles worldwide. The NHTS estimates that there are approximately 23,000 accidents and 535 fatalities annually involving tire underinflation and blowouts [1]. The use of TPMS has been shown to result in improved fuel economy and therefore reduced carbon emissions [2]. TPMS in passenger vehicles was mandated in the US as of Sept. 1, 2007 under the TREAD Act, in the European Union as of Nov. 1, 2012 and in South Korea as of Jan.1, 2013. Countries like Russia, Indonesia, the Philippines, Israel, Malaysia, Turkey and many others soon followed [3]. The first TPMS systems were large and bulky with a significant electronics content [4]. Since that time TPMS electronics have gotten more energy efficient and form factors have come down dramatically. This paper will outline an effort to miniaturize an existing 1.0 mm pitch, 7x7x2.2 mm body size 24 lead QFN (Quad Flat No Leads) TPMS down to a 4x4x1.98 mm body size QFN with 0.5 mm pitch that would still meet automotive AEC Grade 1 reliability requirements. The original 7x7 mm three die QFN package consisted of an ASIC, a pressure sensor and an accelerometer. This miniaturization led to many technical challenges at both the package and board level. This paper will primarily address the board level reliability (BLR) challenges encountered due to the large silicon to package ratio along with the 50% reduction in pitch. Through a series of test vehicles with variables such as QFN leadframe surface finish, lead shape and size, wettable flank (WF) technology and anchors pads, the BLR was successfully improved to the point where it met application requirements.

Indirect tire pressure monitoring system monitors inflation pressures in pneumatic tires using wheel speed sensor (WSS) signals acquired from anti-lock braking system. In order to monitor the tire ...

In order to meet the requirements for high sensitivity and low temperature drift of pressure sensors in the field of meteorological detection or tire pressure monitoring system (TPMS), this paper proposes a MEMS chip-level pressure sensor based on two pairs of aluminum-silicon hybrid structures, which are etched on the SOI wafer. The pressure sensor achieves the amplified piezoresistive effect by the micron thick ohmic contact between the boron-doped silicon and external aluminum shunt, as verified by finite element numerical simulation and experiment. Four symmetrical L-shaped raised structures are distributed around the square strained membrane, which enhance the stress of the pair of stress-sensitive aluminum-silicon hybrid structures. The other pair of hybrid structures placed outside the strained membrane of the sensor chip enables differential sensor output which is highly insensitive to temperature. The offset drift of differential output is reduced to −4.39%FS compared with that of single aluminum-silicon hybrid structure. Cooperated with temperature compensation structures, an additional thermodynamic control system by using PID algorithm to keep the working temperature stable can eliminate the temperature drift of sensor output. The feasibility of the thermodynamic control system is verified by steady-state thermal simulation. Experiment test results show that the sensitivity of a single aluminum-silicon hybrid structure can reach 0.283 mV/V/kPa at constant heating temperature of 50 °C, and whose thermal coefficient of offset (TCO) can be reduced from −6.92E-1 to −1.51E-3 %FS/°C in ambient temperature ranges of −20 to 50 °C.

This paper describes a novel low-cost tire pressure monitoring system (TPMS) for bicycles. The system is based on a battery-less near field communication (NFC) tag that integrates a pressure sensor, which is placed between the tire and the inner tube. The system uses no battery since the energy is obtained from the magnetic field induced by the reader in order to establish the communication. The pressure can be read by any NFC-enabled reader such as a smartphone. The pressure sensor is a force-sensing resistor (FSR) that controls the oscillation frequency of a 555 timer-based oscillator. The frequency is read and computed by a microcontroller, and the result is written via $\text{I}^{2}\text{C}$ bus to the memory of a near-field communication integrated circuit (IC), which is read by a commercial smartphone or NFC reader. A prototype is designed on an FR4 substrate which integrates a $12 \times 16$ mm antenna connected to the NFC IC (NT3H211 from NXP). The proposed prototype has a 3D-printed enclosure to protect the components mounted on the surface of the PCB and to protect the tire from punctures. A system for characterizing the read range is presented. The tag requires a minimum magnetic field of $2.9~A_{RMS}/m$ to operate up to a distance of 8 mm between reader and the tire, providing enough power to supply energy to the whole circuitry and to receive the information stored at the NFC IC. The system has been tested with a 59 mm-width mountain bike tire. The sensor has been characterized using a simple polynomial fitting to obtain the pressure from the measurement of the oscillation frequency. An accuracy of 0.1 has been accomplished in the range of 0.5 to 2.2 bar. To test the system, several inflation cycles have been performed and showed that the system presents good repeatability.

Modern vehicles which have internal sensor networks are one of the examples of a cyberphysical system (CPS). The tire pressure monitoring system (TPMS) is used to monitor the pressure of the tires and to inform the driver of them. This system is mandatory for vehicles in the US and EU. To ensure the security of TPMS, it is important to reduce the cost of the cryptographic mechanisms implemented in resource-constrained devices. To address this problem, previous works have proposed countermeasures employing lightweight block ciphers such as PRESENT, SPECK, or KATAN. However, it is not clear to us that any of these works have addressed the issues of software optimization that considers TPMS packet protection as well as session key updates for architectures consisting of the vehicle TPMS ECU and four low-cost TPMS sensors equipped with the tires. In this paper, we propose the application of ISO/IEC 29192-5 lightweight hash function Lesamnta-LW to address these issues. When we apply cryptographic mechanisms to a practical system, we consider the lightweight crypto stack which contains cryptographic mechanisms, specifications for the implementation, and performance evaluation. Our approach is to apply the known method of converting Lesamnta-LW to multiple independent pseudorandom functions (PRFs) in TPMS. In our case, we generate five PRFs this way and then use one PRF for MAC generation and four for key derivation. We use the internal AES-based block cipher of Lesamnta-LW for encryption. Although we follow the NIST SP 800-108 framework of converting PRFs to key derivation functions, we confirm the significant advantage of Lesamnta-LW-based PRFs over HMAC-SHA-256 by evaluating the performance on AVR 8-bit microcontrollers, on which we consider simulating TPMS sensors. We expect that our method to achieve multiple purposes with a single cryptographic primitive will help us to reduce the total implementation cost required for TPMS security.

The objective of this paper is to detect the car driver behavior. Many factors can influence the behavior of the driver that includes fatigue, distraction, eye-blinking, taking eyes off from the road, time of the driving etc. The in appropriate behavior while driving the car can leads to accidents that in return damages one’s life or the vehicle. The papers discuss the various techniques to monitor the driver behaviors and describes the advantages and disadvantages of the methods used to detect the driver behavior in a car.

This paper presents a new indirect tire pressure monitoring system (TPMS) based on adaptive extended Kalman filtering with unknown input (AEKF-UI) estimation of vehicle suspension systems. The suggested methodology is based on the explicit correlation between tire pressure and tire stiffness and is available in real time. AEKF-UI is used to simultaneously estimate the time-varying parameter (tire stiffness) of vehicle suspension systems and the road roughness using an unknown input estimator. Simulation studies demonstrate that the proposed algorithm can simultaneously estimate tire stiffness (i.e., tire inflation pressure) variation and unknown road roughness input. The feasibility and effectiveness of the proposed estimation algorithm are verified through a laboratory-level experiment. This study offers a potential application for an alternative indirect TPMS and the estimation of unknown road roughness used for automotive controller design.

Currently, the Tire Pressure Monitoring System (TPMS) only monitors the condition of a tire pressure. However, there are no particular reactions taking place after the value of its tire pressure is discovered. In fact, the value of a tire pressure determines driving comfort and safety Therefore, this research proposed a method to integrate a TPMS and a Pressure Sensor Base (PSB) with a particular reaction required to fulfill tires automatically. The proposed TPMS has an electronic device unit directly attached to a tire’s valve. This unit includes pressure sensors, microcontrollers, Bluetooth transmitters and batteries. An alert system is generated whenever tire pressure exceeds the maximum or minimum safe pressure level. Moreover, if the pressure measured is below the lowest level of the desired pressure, it will automatically activate the compressor. Several experiments have been carried out to analyze the proposed system. The integrated TPMS has proven to be able to be an alternative tool for the automotive sector to keep maintaining the tires and to improve a driving comfort and safety.

Automobile instrument clusters these days are equipped with numerous warning icons for informing drivers on different critical automobile functions. In this context, abstract and complex icon designs can often be misinterpreted. Use of icons that do not reveal their functionality through their visual characteristics increases the risk of road accidents. Designers often follow relevant guidelines before designing usable warning icons. To warning icons namely ‘Brake Warning Light’ (BWL) and ‘Tire Pressure Monitoring System’ (TPMS) were found to be the poorly usable icons in past research work by the authors and other researchers. The intent of this study is to design and evaluate usable alternative designs for these two icons in the Indian context. Standard available guidelines and Peirce’s model of semiotics were adopted during this work. 50 participants volunteered in the first study to report their respective concerns with the two icons. Four alternatives each for the two icons were designed and in a second study, they were rated by 60 volunteers on the perceptual factor of ‘semantic closeness’.

In the past few years, automobile dashboard and its instrument panel are becoming increasingly complicated as they offer a variety of digitized functionalities such as warning icons. Past research shows that certain automotive warning icon designs could be hard to interpret by drivers. A study was undertaken for determining the usability of certain standard warning icons in automobile instrument clusters using system usability scale (SUS) and also to investigate the “guessability” of these icons. Here, a set of 20 standard warning icons which are commonly used in new models of Indian cars were selected from ISO 2575:2010, and 50 participants were employed to determine the usability and guessability of these icons. Standard designs of two car dashboard warning icons, namely “Brake Warning Light” and “Tire Pressure Monitoring System” were found to be problematic. A significant and strong positive correlation was found between the mean guessability score and the mean SUS score for all the 20 warning icons.

This paper presents an energy-efficient wireless transmission scheme for battery-less vehicle tire pressure monitoring system (TPMS). Our proposed transmission scheme includes a wake-up communication link with 125-kHz carrier frequency and a data communication link with 433-MHz carrier frequency. Considering the TPMS application requirements and the special nature of the vehicle environment, we derive the relevant circuit parameters. In order to verify the reliability of the wireless communication system under the derived circuit parameters, we design an in-tire data transmitter and wake-up receiver. The 125-kHz wake-up receiver adopts dual-channel to improve the communication reliability and logarithmic amplifiers to achieve ASK demodulation and dynamic range compression. The receiver is implemented in 0.35- $\mu \text{m}$ high voltage (HV) BCD process. Experiment results show that typical power consumption of the receiver is no more than $5~\mu \text{A}$ under 3.3 V supply voltage; the maximum data rate is 35 kb/s with 0.5 mVpp sensitivity. On the other hand, the data transmitter is implemented in 0.18- $\mu \text{m}$ MMRF process. Experiment results show that the typical power consumption is 7.3 mA under 1.8 V supply voltage, and the emission power is −10 dBm@433.92 MHz with a phase noise of −103 dBc/Hz@300 kHz. System level experiments demonstrate that the proposed wireless transmission scheme fulfills the vehicle TPMS requirements. The data transmitter and wake-up receiver can communicate with the commercial data receiver and wake-up transmitter in the range of 20 m, which meets the requirements of most vehicles.

The tire pressure monitoring system (TPMS) research is mostly concentrated in the ultralow-power circuit field. However, one of the biggest challenges is overcoming the unavoidable replacement of batteries owing to their self-discharging, unstable performance by using the energy-harvesting technology. A TPMS must be installed on the wheel surface for permanent operation. Likewise, the energy harvester should be directly installed inside the TPMS circuit to eliminate any additional maintenance. Thus, the size of the energy harvester for independent rotational systems, such as a tire wheel, should be constrained to the battery level. Electromagnetic induction was selected to maximize the power generated by the energy harvester. The optimized model was rationally examined, and the results were compared with the calculated results. In preliminary modeling of the mechanical energy transduction into electrical energy and the parameters in the m-c-k system, the module was predicted to generate about 136 μW of consumable power. A test module was fabricated for practical application. With the experimental constraints, the maximum power consumption was 195 μW under the conditions of a base excitation of 12 Hz and acceleration of 0.5 g for a system volume of about 2.5 cm3.

Since the National Highway Traffic Safety Administration mandated the incorporation of tire pressure monitoring systems (TPMSs) in all newly produced passenger vehicles, most vehicle manufacturers have adopted direct pressure measurement. Direct TPMS sensors embedded in each tire require a wireless radio frequency (RF) communications link that broadcasts tire status to the vehicle once per minute from each tire when at speed. Each TPMS message communicates benign information that includes pressure and temperature as well as a static unique identifier that may be exploited, which raises concerns about privacy and spoofing. To focus on concerns related to the TPMS-RF interface, vehicle motion simulations were integrated with live propagation modeling measurements from three classes of passenger vehicles: subcompact car, full-size sedan, and full-size pickup. The RF link and channel models for this TPMS interface with the vehicle resulted in surprisingly long ranges away from the vehicle for the radiation of the unique identifiers. A TPMS sensor redesign could use the proposed RF channel propagation measurements to change the directions of signal propagation while reducing battery consumption by the TPMS sensor (which is affected primarily by RF transmission).

The automotive sector is currently in a dynamic change by the introduction of new vehicle concepts, like electric and autonomous vehicles, and innovative driver assistance systems like systems for a precise adaptive headlight adjustment. The continuous adjustment of the headlamps is very important for the correct illumination of the road and prevention of blinding the oncoming traffic, respectively. Hence, a great share of new vehicles possess an automatic headlight adjustment. In some countries, like Germany, these systems are legally required for some kinds of headlights. Nevertheless, there are only a few suppliers for aftermarket products and thus, the product range of automatic headlamp adjustment systems for existing vehicles is low. This paper presents a system concept for the aftermarket that is modular designed and easy to integrate in existing vehicles. In addition, the concept includes a novel approach by the application of a smart tire pressure monitoring system for the detection of the tilt angle of the vehicle. Therefore, consumers who like to change their light technology (e.g. LED instead of halogen headlights) and to integrate a system for headlight adjustment can benefit from the system shown in this paper.

A novel on-chip integration of pressure plus 2-axis (X/Z) acceleration composite sensors for upgraded production of automobile tire pressure monitoring system (TPMS) is proposed, developed, and characterized. Herein, the X-axis accelerometer is with the cantilever beam-mass structure and is used for automatically identifying and positioning each of the four wheels. The IC-Foundry-Compatible low-cost batch fabrication technique of MIS (i.e., Micro-openings Inter-etch and Sealing) is employed to only fabricate the device from the front side of (111) silicon wafer, without double-sided micromachining, wafer bonding, complex Cavity-SOI (Silicon on Insulator) processing, and expensive SOI-wafer needed. Benefited from the single-wafer front-side fabrication technique on ordinary single-polished wafers, the fabricated composite TPMS sensor has the advantages of a small chip-size of 1.9 mm &times, 1.9 mm, low cross-talk interference, low-cost, and compatible process with IC-foundries. The fabricated pressure sensors, X-axis accelerometer and Z-axis accelerometer, show linear sensing outputs, with the sensitivities as about 0.102 mV/kPa, 0.132 mV/kPa, and 0.136 mV/kPa, respectively. Fabricated with the low-cost front-side MIS process, the fabricated composite TPMS sensors are promising in automotive electronics and volume production.

Recent studies have shown that ‘’hacktivists’’ can mount serious attacks on automobiles. The automotive On-Board Diagnostic (OBD) interface enables an efficient way to access information of the in-vehicle electronic system and leaves way for unauthorized access by an intruder. We discover that remote exploitation is feasible via a broad range of attack points such as mechanic tools, CD players, Bluetooth and Tire Pressure Monitoring System. Wireless communications channels allow long distance vehicle control. Finally, the paper discusses the drawbacks of Seed-Key Mechanism to authenticate and provide an extra layer of authentication to help build a safer automotive ecosystem.

This paper presents the tire pressure monitoring system (TPMS) by using the system on chip (SoC) mixed signals with the help of Bluetooth transmission and in advantage of low power consumption design. This is to monitor the variations in temperature and pressure of the vehicle’s tire, and the TPMS system is involved. It improves the driver’s safety by automatically detecting the tire pressure and temperature and then warning signal is sent to driver to take a measure, which prevents from accident. The proposed system of tire pressure monitoring system using SoC increases the speed of indication time to the driver by using mixed signals. The inflation of the tire can be avoided by preventing from high temperature and high pressure. Limitation of temperature and pressure in the previous system is also elongated i.e. temperature from 40℃ to 125℃ and pressure from 0 to 750 Kpa. Sensors, wireless communication (Bluetooth dongle) and SoC unit are used to design the low power TPMS. Quantitative results are taken and the analogy between temperature and pressure is also verified. The tested results proved by need of the practical system. Signal conditioning voltage and SoC unit is the trace for low power design TPMS. Finally, the performance of the system is tested and executed by using proteus software given as a real time application.

The aim of this study is to explore whether risk perception or anticipated regret is responsible for intensifying the participants’ intention to adopt a tire pressure monitoring system (TPMS) to prevent a tire-related accident, and whether the optimism bias has a moderator effect between risk perception/anticipated regret and intention. With 274 valid questionnaires and PLS-SEM (partial least squares structural equation modeling) analysis, the results indicate a significant positive relationship between risk perception and intention to adopt TPMS, but not between anticipated regret and intention. The moderator effect of optimism bias on risk perception and anticipated regret is not found in the model. The findings will prove useful for public service advertising campaigns by providing a basis for an understanding of the role of cognitive and emotional factors in tire-blowout accident prevention, thereby increasing the motivation for drivers in Taiwan to take advantage of the protection afforded them by using TPMS.

A 125 KHz wake-up receiver to receive wake-up signal and a 433MHz data transmitter to transmit temperature and pressure data of the tire to central control module for battery-less TPMS (Tire Pressure Monitoring System) are presented in this paper. The receiver adopts dual-channel to improve reliability and logarithmic amplifier to achieve ASK demodulation and dynamic range compression. The receiver is implemented in 0.35μm BCD process. Maximum data rate is 35Kbps with 0.5mVpp sensitivity and 5μA typical power consumption. The transmitter is implemented in 0.18μm process. The typical power consumption is 7.3mA with a transmit power of −10 dBm@433.9 MHz, and phase noise of the PLL is − 103dBc/Hz@ 300 KHz with 30Kbps data rate.

In this paper, the performances of several tire temperature and pressure sensors in Tire Pressure Monitoring System (TPMS) were analyzed, and the corresponding IC and MEMS core technology in R&D of the active and passive sensors was studied. It is pointed out that the passive wireless sensor chips based on the surface acoustic wave (SAW) is the development direction in automotive safety products. In addition, this paper analyzed the principle, working process and the development of SAW sensors in recent two decades. As to the current international technical barriers, the patent technologies of the SAW sensor were presented, and the international competition and cooperation were discussed. Finally we draw the conclusions that in order to break the technical barriers of European and American automobile trade, it is quite necessary to develop the core technology of SAW sensors, together with the independence, resources integration, business risk control and the perfection of patent law, due to the huge economic benefits of the SAW sensors.

Recently, vehicle safety has become very important in the automobile industry. TPMS(tire pressure monitoring system) is also one of the vehicle safety systems. Recent studies of TPMS are proceeding in the fields of low power operation, battery-less system, and tire location registration. In this paper, we analyze the conventional tire location registration algorithms in which the simplex communication is used. And we propose a new algorithm that uses Inter Frame Spacing Pattern to identify the location of each tire. By implementing TPMS with proposed tire location registration algorithm, we confirmed that all sensors are registered normally within about 3 minutes.

This study aims to experimentally investigate accordance between tire pressure and vertical deflection of tire in order to use in TPMS (Tire Pressure Monitoring System). For this aim, the resonance frequency of vertical deflection of tire is determined by using test results. For this, the road tests have been conducted on flat and dry road for measuring the tire deflection. These tests are run at constant vehicle speeds 30 and 100km/h for tire pressures 15, 20, 25, 30, 35psi. Therefore, the vertical deflection changes have been measured under same road conditions with different vehicle speeds. The frequency responses of the measured vertical deflections are obtained by using (SRMS) root mean square of sampled vertical deflection signals. The resonance frequency of the vertical deflection is taken from the frequency responses. The results show that the accordance between tire pressure and vertical deflection of tire can be achieved irrespective of the changes in vehicle speed. Consequently, the algorithm to detect the drops in tire pressure based on tire deflection is developed by using the time and frequency domain results.

This paper reports on the successful implementation of a wafer-level vacuum-packaged, CMOS-compatible aluminum nitride (AlN) based microelectromechanical system (MEMS) energy harvester (EH). The reported EH features high Q-factor (709.3) and high-g survivability (harmonic at 20g), achieved through wafer-level vacuum-package scheme which reduces the air damping effect and increases the Q-factor, overcoming the tradeoff between vibration amplitude and output power density for EHs operated in air. A power of 468.77µW, bandwidth of 71Hz (3.66%) is delivered by a ~0.119cm3 footprint (1×0.7×0.1705cm3) EH at 20g sinusoidal input vibration, equates to a record power density of ~3.93mW/cm3. This novel packaging and design scheme, which utilizes two-step three-wafer wafer level eutectic bonding, allows size reduction and shock-resilience improvement of future EH. The ability to harvest broad spectrum mechanical vibration energy with small footprint and high-g survivability, makes the reported EH one step closer towards powering the next generation battery-less Smart Tire Pressure Monitoring System (TPMS). Furthermore, the whole integration process, including the wafer-level vacuum-packaging process, is CMOS compatible, making the reported EH viable for mass production with low fabrication cost.

The monitoring system of tire pressure is regarded as a security product of a new generation of vehicles equipped with high-technology. At present the tire pressure monitoring system can not detect tire pressure all the whole time and tire malfunction can not alarm in time too, this paper proposes an intelligent tire pressure monitoring and alarming system. This paper introduces the overall structure of system and describes the implementation method of system design from two aspects of hardware and software. The system can monitor the tire condition in time and alarm for abnormal situation. It has some advantages in low power consumption, reliability and security.

At present, the most convenient and effective method for ensuring air pressure inside automobile tires being kept in normal state is using a tire pressure monitoring system to monitor the tire’s interior pressure and temperature in real time. Aiming at the power supply problem of direct tire pressure monitoring system in automobile industry commonly, a new giant magnetostrictive vibration-power generation technology which generates electricity through collecting vibration energy in automobile is proposed. Based on the coupling effect of inverse magnetostrictive effect and Faraday electromagnetic effect, a power generation device prototype which uses giant magnetostrictive material as the core element is developed. It may be a prototype of giant magnetostrictive vibration-power generation module used to provide electricity to tire pressure monitoring system instead of button battery power supply mode. In order to accurately describe the relationship between vibration force (stress) and output voltage in the giant magnetostrictive vibration-power generation process, a mathematical model is established from the essence of inverse magnetostrictive effect. According to energy conversion process generated in the process of power generation using giant magnetostrictive material, the modeling process is divided into two parts. Moreover, in order to derive the energy conversion efficiency of giant magnetostrictive vibration-power generation device, a computing method of power generation efficiency is proposed. Experiment results show that the model can accurately describe the relationship between vibration force (stress) and output voltage. Amplitude of the output voltage generated by giant magnetostrictive vibration-power generator is proportional to the amplitude or frequency of vibration force approximately. For the giant magnetostrictive vibration-power generation prototype developed in this paper, its energy conversion efficiency reaches 32.6%. Research result provides an effective method for solving the power supply issue of tire pressure monitoring system. It plays a certain promoting role for the realization of battery-less tire pressure monitoring system.

The TPMS can not only save fuel and protect the tire, but also make the driver more safety. Tire safety is attracting the driver's attention, the United States had developed laws to enforce the TPMS installation in the car and the deadline is in 2008. In this paper, the basic structure and the implement method of TPMS are introduced. The active sensors are already used in most of the TPMS applications. The SAW theory and some wireless passive SAW pressure and temperature sensors which suit for the TPMS application are illustrated, because the passive sensor is becoming the focus in the TPMS research field. Passive SAW sensor is the good choice for TPMS, according to its wireless, passive, zero age rate, small size etc. The wireless passive SAW TPMS is one of the most important research direction. In this paper, some kinds of passive SAW sensor are introduced, which are used in TPMS.

A Automobile tire is an important part of the car, and its safety and reliability will directly related to the passengers' safety. This paper puts forward a kind of automobile Tire Pressure monitoring system (Tire Pressure Monitoring System, TPMS), adopting the Infineon company's SP37 chips used for collecting and sending data of automobile tire's Pressure in time, adopting MAX1473 chip wireless to receive, relying on the MSP430 chip's dealing with data from the tire Pressure, also, and warning to drivers so as to avoid accident. This thesis mainly introduces the design of the system's hardware, software.

In order to make the embedded system without large memory capacity and embedded operating system can use database to manage data for itself, this paper puts forward a universal model of embedded database combining the characteristic of embedded database. It studies the structure of the model and applies it to tire pressure monitoring system (TPMS). It discusses the hardware design, file frame, physical structure and logical structure of the embedded database of TPMS. Then it sets up a reliable, real-time, convenient database for TPMS. This database will manage the data which come from TPMS effectively when automobiles are running. It makes TPMS can analyze the status of driving car scientifically and provide reliable tire information.

Tire pressure monitoring system (TPMS) is used to monitor fast or slow tire pressure loss or too high tire temperature, and ensure the safety of the drivers and the passengers. A new kind of TPMS as the core of MSP430F149 microcontrollers is put forward, which based on Wireless Sensor Network. It adopts Infineon SP370 new sensor as the transmitter and TDA5220 as the receiver. The whole system scheme, hardware and software design are expounded in this paper. A low cost, low power consumption and high precision TPMS is studied, and the tire pressure and temperature can be immediately and real-time measured.

Tire Pressure Monitoring System (TPMS) is an auxiliary safety system for recognizing the condition of tires based on the pressure and temperature data transmitted from the sensor unit installed on a tire of the vehicle. Using TPMS, a driver can frequently check the state of tires and it aids to maintain the optimum running condition of the vehicle. Since TPMS must utilize the wireless communication technique to transmit data from a sensor unit to a signal processing unit installed in the vehicle, it suffers from interference signals caused by various external electrical or electronic devices. In order to suppress high-power interference signals, we employ beamforming techniques based on the uniform linear antenna array. As the number of the antennas is increased, the performance of the interference suppression is improved. However, there is the limit of the number of antennas, installed in the center of a vehicle, because of its size. In this paper, we compare and analyze the performance of the beamformer, when reducing the interelement spacing of antennas, to increase the number of the receiving antennas. For the performance analysis of the beamformers, we consider the switching beamformer and minimum-variance distortionless-response (MVDR) beamformer for TPMS, recently proposed.

The new tire pressure monitoring system (TPMS) needs rigorous testing to ensure product reliability before it is put into use. But traditional means usually used real vehicle running tests, with more energy consumption, and for a wide-range test was difficult to make. To this end, in this paper, a new TPMS test management system was proposed, which was a good solution to the above problem. The scheme is based on the advanced ZigBee wireless network technology and the RS-485 bus technology to achieve a system of joint networking, the programmable software management system based on JSP and SQL Server 2005 database, made good and practical effect.

Vehicles are increasingly wirelessly connected and each wireless connection is a potential cyber threat surface. Many of these wireless communications are related to the infotainment systems and are optional, some are not. Since 2008, when the U.S. government mandated the need for real-time tire pressure diagnostics, automotive manufacturers have inserted Tire Pressure Monitoring System (TPMS)-based devices in all vehicles sold domestically. These sensors are divided into “direct” and “indirect” TPMS based on the mechanisms used to observe the tire pressure, temperature, and other characteristics; while marginally more expensive, most such systems are directly embedded in the tire to achieve the diagnostics requirements stated in National Highway Traffic Safety Administration [1], [2], necessitating a wireless communications link back to a car's Controller Area Network (CAN) bus and engine control unit (ECU). In this paper, we seek to evaluate the cyber-security of that TPMS wireless communications interface, proposing and evaluating the viability of incorporating a more secure TPMS protocol that takes advantage of simple linear feedback shift register (LFSR)-based message encryption. The proposed models were designed and implemented in both a Universal Serial Radio Peripheral (USRP) N210 software defined radio (SDR) testbed that replicates each side of the TPMS link; the resulting capabilities were also simulated on an inexpensive Arduino platform to demonstrate cost realism in the threat to the TPMS system.

The main purpose of this paper is to present a software implementation referring to an indirect Tire Pressure Measurement System (iTPMS) based on the Anti-lock Braking System (ABS) present in a car. The novelty of the research is the achievement of a Simulink car model which is able to feed simulated data consistent with real-life measurements to the hardware system for functional testing of the implemented measurement method, without the need of an actual car and road test. An additional Android application is implemented for the purpose of helping the driver to determine and solve the problem stated by the possibility of appearance of tire under inflation.

Modern vehicles offer a raw territory for designing security solutions as the over-increasing design complexity demanded massive advances in electronics in the absence of a crisp vision over the adversary model. The vehicle Tire Pressure Monitoring System (TPMS) is a sub-system that recently triggered some attention in the light of several reported attacks. In this work we start from analyzing existing proposals and reckon some shortcomings, e.g., academic proposals are not yet tested on real-world components while a patented security solution from the industry (likely deployed in practice) is completely insecure. Motivated by these, we design a new solution and deploy it on real-world components that are used in the automotive industry. Designing security for this subsystem proves to be especially relevant as the computational resources for TPM systems are somewhat at the minimum to be found in automotive embedded devices. Our solution is deployed on Infineon SP37 sensors and takes advantage of some recently proposed light-weight cryptographic designs, e.g., SPECK and PRESENT.

A TPMS(Tire Pressure Monitoring System) is a wireless communication system designed to monitor the pressure and temperature of pneumatic tires of a vehicle. In order to provide the aid in protecting a driver, this system reports tire pressure information to the driver of the vehicle. Since the wireless communication technique should be employed to transmit the TPMS data from each tire to signal processing unit in the vehicle, it suffers from interference signals from external electrical or electronics equipments. In this paper, we propose the TPMS interference cancellation technique based on GSC(Generalized Sidelobe Canceler), which does not have only the excellent performance like MVDR(Minimum-Variance-Distortionless-Response) but also has the low computational complexity comparing with MVDR. The performance of interference suppression is conformed by computer simulation examples.

Many traffic accidents took place during the vehicle running, the main reason were some tire gas leakage, the lower tire-pressure, the higher temperature, and so on. So it was an important work to us to monitor the running state of tire. An intelligent Tire Pressure Monitoring System based on wireless radio frequency technique was designed. The Tire Pressure Monitoring System utilized a special sensor to test tire-pressure and temperature of interior tire, through a transmitting & receiver circuit to transmit and receive these signal, when the System got the working-state by processing these data and then warned us some danger exist in advance, which make us took some method to avoid these accident occurred. All these work will great decrease the traffic accidence.

During parameter acquisition of rotating components, wireless data transmission is an efficient way. In this paper, electromagnetic (EM) wave propagation characteristics in rotating environments are preliminarily studied in order to provide a strong theoretical support for developing high-performance radio monitoring systems in rotating environments. The mathematical formulation of signal wave propagation between the transmitting antenna and the receiving antenna in time-dependent rotating motion is derived. The Doppler frequency shift and the EM wave polarization characteristics in rotating environments are presented and analyzed. The two-ray propagation model in rotating environments is proposed, and the validity of the model is verified by experimental results. Taking tire pressure monitoring system (TPMS) as a typical example, key parameters affecting wireless data transmission from a rotating transmitting antenna are investigated, and system performance enhancement strategies are proposed. Power transmission tests were conducted on a TPMS operating at different frequencies and different rotating radii relative to wheel rotation axis. The test results show that the path loss and the path loss fluctuation sharpness increase with the operating frequency and the rotating radius. Moreover, the path loss for most rotation angle values decreases drastically at lower frequencies and lower radii. Wireless data transmission tests were implemented for both the improved TPMS and the old TPMS. The test results show that the receiving probabilities of successful data frame transmission are improved greatly.

An integrated system is proposed of base station module, key module and tire modules, in order to overcome the independence of tire pressure monitor system, remote keyless entry and immobilization of engine. Tire modules or key module communicate base station module with UHF frequency signal of 434MHZ. The transponder PCF7961 in key module and PJF7992 in base station module authenticate mutually with LF frequency signal of 125KHZ. The result is shown that the system can improve the security and controllability of cars, compress system redundancy, reduce produce costs and optimize the skeleton network.

TPMS (Tire Pressure Monitoring System) has played a more and more significant role in safely driving nowadays. Low power consumption and excellent accuracy are two of the most important parameters. In this paper, a TPMS with driving status judgment and low-power measurement is designed and realized. A vibration switch is applied to judge the different status of running and stopping. Based on the judgment of driving status, pressure and temperature, different operations will be carried out in order to achieve lower power consumption. The whole system is working intermittently. It has a good performance with a theoretical lifespan of 2 years. The tested communication distance is more than 30m and the resolution is better than 4KPa. A MEMS pressure sensor using SOI wafer with high consistency and accuracy for this TPMS is designed and fabricated. Deep trench etching is adopted to make pressure reference cavity. The ratio of sensitivity variance to its average is 3.5%, which illustrates a good consistency. The total accuracy of the sensor is better than 0.3% and the nonlinearity is less than 0.2%.

Problem statement: This study presents a wireless sensor node dedicated for in-tire pressure and temperature monitoring. Additional features set it apart from the many different systems available on the highly competitive market. State-of-the-art implementations are mounted on the rim of a tire. Here the sensor node will be mounted on the inner liner of the tire. By moving the sensor node from the rim to the inner liner, new challenges in the analog design arise. Approach: To implement this sensor node new power supply methods are investigated. Next, analog designs with the focus on low power are developed. Since the sensor node is operated in a harsh environment, robustness is a key issue. Results: The discussed sensor is capable of either active or passive communication. The passive communication is used in the field of Radio Frequency Identification (RFID), whereas active communication is used to transmit the sensor data. A combination of both is also possible. To supply the chip in the tire an RF energy harvesting interface is implemented. An input sensitivity of -19.7dBm for the harvesting interface and -12.5 dBm for the RFID interface is measured. The on-chip temperature sensor consumes 4μA including the analog to digital converter. Conclusion: Choosing the discussed sensor node for in-tire monitoring enables new fields of applications. With this sensor node sensing additional parameters like road condition is possible. Using passive communication improves warehouse management for tire manufactures. Also, tire type identification at the car is enabled.

Objective of the paper is to promote the proactive approach in tire maintenance for commercial vehicles and application of the Tire Pressure Monitoring System (TPMS). Researches have confirmed that the installation of TPMS on commercial vehicles is technically and economically justified, namely traffic safety and comfort of passengers would thus be significantly improved and operating costs would be decreased. Example of articulated city bus shows that the investment in the Tire Pressure Monitoring System would be recovered in the second year of operation.

A new kind design scheme of sensing system for tire pressure monitoring system was introduced in this paper. In order to measure the condition of the tire in real time, MCU, MEMS sensor, thermometer, and wireless communication technology is used in this new system. The MEMS sensor and RF emitter was directly installed in tire. It was transmitted for receiver installed in cab by wireless after gas pressure data gathered. It sensed in time pressure condition by receiver, so that driver adopted corresponding countermeasure. The design of hardware and software is discussed in details.

This paper deals with the interface-relevant activity of a vehicle integrated intelligent safety system (ISS) that includes an airbag deployment decision system (ADDS) and a tire pressure monitoring system (TPMS). A program is developed in LabWindows/CVI, using C for prototype implementation. The prototype is primarily concerned with the interconnection between hardware objects such as a load cell, web camera, accelerometer, TPM tire module and receiver module, DAQ card, CPU card and a touch screen. Several safety subsystems, including image processing, weight sensing and crash detection systems, are integrated, and their outputs are combined to yield intelligent decisions regarding airbag deployment. The integrated safety system also monitors tire pressure and temperature. Testing and experimentation with this ISS suggests that the system is unique, robust, intelligent, and appropriate for in-vehicle applications.

Attaching a tire pressure monitoring system (TPMS) on the inner liner of a tire allows sensing of important additional technical parameters, such as vehicle load or tire wearout. The maximum weight of the sensor is limited to 5 grams including package, power supply, and antenna. Robustness is required against extreme levels of acceleration. The node size is limited to about 1 cm3 to avoid high force-gradients due to device-deformation and finally, a long power supply lifetime must be achieved. In this paper a low-power FSK transceiver is presented. Exploiting BAW resonators the use of a bulky and shock-sensitive crystal and a PLL can be avoided. This makes the system more robust and radically reduces the start-up time to 2 ?s from few ms as in state-of-the-art crystal oscillator based systems. The current consumption of the transceiver is 6 mA in transmit mode with a transmit output power of 1 dBm and 8 mA in receive mode with a sensitivity of -90 dBm at a data rate of 50 kBit/s and a bit error rate of 10-2. The transceiver ASIC and a microcontroller ASIC, a MEMS sensor, and a BAW die are arranged in a 3-D chip stack for best compactness, lowest volume, and highest robustness. The sensor node allows sensing of pressure, acceleration, supply voltage and temperature.

A miniature printed sleeve meander antenna used in tire pressure monitoring system (TPMS) is proposed in this paper. By using the meander structures including the radiation patch and ground plane, the antenna provides a degree of 78% miniaturization. Meanwhile, a L-shaped stub is loaded on the meander ground to improve the impedance bandwidth, thus a wide bandwidth of 24.2% (VSWR < 3.0) and 13.8% (VSWR < 2.0) for TPMS application is obtained. The antenna has good radiation pattern characteristic, and its performance is relatively stable. Design details of the proposed antenna and results of both simulations and experiments are presented and discussed.

The vehicles being operated without tire pressure monitoring system (TPMS) is posing a significant safety problem. To solve the problems, number researches have been widely investigated. However, factors of limitation described in introduction are still the major concern. Hence, the appropriate systems of TPMS are still being investigated. This paper deals with development of TPMS that contributes significantly towards the enhancement of the intelligent vehicle safety application. A detailed overview on tire pressure monitor (TPM) and receiver modules development such as data acquisition, communication protocol, Manchester encoding algorithm and interface programme are demonstrated. The performance evaluation of the experimental results of the TPMS shows that data acquisition, complete messages of pressure and temperature and real-time monitoring are unique and advance. Thus, the experimental result is therefore ensures the data monitoring and provides warning to validate the usefulness of the TPMS system...

this paper presents a wireless surface acoustic wave (SAW) pressure sensor on 41oYX LiNbO3 for tire pressure monitoring system (TPMS) application, in which a reflective delay line composed of an interdigital transducer (IDT) and several reflectors was used as the sensor element. Using the coupling of modes (COM), the SAW reflective delay line was simulated, and the optimal design parameters were determined. The fabricated 2.4GHz SAW sensor was wirelessly characterized by the network analyzer. Sharp reflection peaks, few spurious signals, and relatively high signal-to-noise (S/N) ratio were observed. High sensitivity of 2.9 deg/kPa and good linearity were observed.

A novel pressure microsensor is designed, fabricated and tested. Novel piezoresistive sensing structures using 30- mum thick silicon diaphragms (from 370 mum times 370 mum to 970 mum times 970 mum ) and meander-shaped piezoresistors are devised. The diaphragms in this work thicker than that of the conventional piezoresistive pressure sensors extend the high-stress distribution into the bulk silicon and improve the device reliability. Piezoresistors are partially fabricated on the high-stress bulk silicon to obtain high sensitivity and linearity. Effects of different diaphragm areas, piezoresistor shapes, and placing methods on the sensing performances are simulated, measured, and analyzed. The whole fabrication is low-cost and compatible with standard IC process. Measurement shows promising results, i.e., large test region (0-1 MPa), high sensitivity (70.4 mV/VldrFS ), small linearity error (0.012%/FS) and good precision (0.16%/FS). The work indicates a novel solution of small size, high-performance, high-reliability, and low-cost pressure microsensor for tire pressure monitoring system and many other applications.