Simulation of a Novel Bridge MEMS-PZT Energy Harvester for Tire Pressure System

Self-powering is becoming an important issue for autonomous sensor systems. By having an on-the-go power source the life span increases in comparison to a limited battery source. In this paper, simulation of an innovative design for a piezoelectric energy harvester for Tire Pressure Measurement System (TPMS) is presented. The MEMS-based thin-film PZT harvester structure is in the form of a bridge with a big central seismic mass and multiple electrodes. This design takes the advantage of the S-profile bending and a short beam length to concentrate the piezoelectric effect in a small segment along the beam and maximize the power output for a given displacement. From simulation in Comsol Multiphysics, the 9mm x 5mm bridge, seismic mass of 8.7mg and resonance frequency of 615Hz, generates 1 mu W by mechanical pulses excitation equivalent to driving at 60 km/h (roughly 180G)

TYRE PRESSURE MONITORING SYSTEM

Maintaining the correct tyre pressure for a vehicle is the variable in how much load its tyres can safely carry. The correct pressure will carry the weight without a problem. Too little tyre pressure will eventually cause catastrophic tyre failure. This project requires student to study the existing system ofTPMS and ifpossible to come up with depth research on how to design the system from scratch. This project is the initial background work for the development of a miniature pressure sensor and controller unit for TPMS. The main purpose ofthese systems is to warn the driver if their tyres are losing air pressure, leaving the tyres under inflated and dangerous. The systems attach a pressure sensor together with transmitter to the vehicle's wheel inside the tyre's air chamber. The final objective ofthe continuous project is to design a circuit consists ofpressure sensor, microcontroller (PIC), transmitter and receiver. The pressure sensor used is amicroelectronic device. This system will read apressure inside the tyre and transmit itto the receiver which can produce the output (display). This report represents approaches to the scope of developing the MEMS pressure sensor which used inTPMS. The methodology divided by two; TPMS methodology and MEMS pressure sensor methodology. For the TPMS methodology, input from pressure sensor is required before a transmitter unit transmits the data to a receiver and displays the value of the pressure. For the MEMS methodology, it was divided into mechanical and electrical design elements. Mostly the related information is collected from reference books and from internet. As for the conclusion tyre pressure monitoring system is an interesting area of focus and opens up a new field of technology and creative thinking

TPMS Receiver Hacking

In 2005 the Department of Transportation made it mandatory for all new cars to be installed with a tire pressure monitoring system (TPMS). The TPMS system typically consists of transmitters in the tires and a receiver within the car. This project was the first in a series of projects designed to investigate the security vulnerabilities between a tire pressure monitoring sensor and the receiver within the car. Through controlled, distance, and roadside testing a generic receiver was designed using the universal software defined radio (USRP) and MATLAB for all TPMS variants

Towards Intelligent Tire and Self-Powered Sensing Systems

Tires are the interface between a vehicle and the ground providing forces and isolation to the vehicle. For vehicle safety, stability, maintenance, and performance, it is vital to estimate or measure tire forces, inflation pressure, and contact friction coefficient. Estimation methods can predict tire forces to some extent however; they fail in harsh maneuvers and are dependent on road surface conditions for which there is no robust estimation method. Measurement devices for tire forces exist for vehicle testing but at the cost of tens of thousands of dollars. Tire pressure-monitoring sensors (TPMS) are the only sensors available in newer and higher end vehicles to provide tire pressure, but there are no sensors to measure road surface condition or tire forces for production vehicles. With the prospect of autonomous driving on roads in near future, it is paramount to make the vehicles safe on any driving and road condition. This is only possible by additional sensors to make up for the driver’s cognitive and sensory system. Measuring road condition and tire forces especially in autonomous vehicles are vital in their safety, reliability, and public confidence in automated driving. Real time measurement of road condition and tire forces in buses and trucks can significantly improve the safety of road transportation system, and in miming/construction and off-road vehicles can improve performance, tire life and reduce operational costs. In this thesis, five different types of sensors are designed, modelled, optimized and fabricated with the objective of developing an intelligent tire. In order to design these sensors,~both electromagnetic generator (EMG) and triboelectric nanogenerators (TENG) are used. In the first two initial designed sensors, with the combination of EMG and TENG into a single package, two hybridized sensors are fabricated with promising potential for self-powered sensing. The potential of developed sensors are investigated for tire-condition monitoring system (TCMS). Considering the impressive properties of TENG units of the developed hybridized devices, three different flexible nanogenerators, only based on this newly developed technology, are developed for TCMS. The design, modelling, working mechanism, fabrication procedure, and experimental results of these TENG sensors are fully presented for applications in TCMS. Among these three fabricated sensors, one of them shows an excellent capability for TCMS because of its high flexibility, stable and high electrical output,and an encapsulated structure. The high flexibility of developed TENG sensor is a very appealing feature for TCMS, which cannot be found in any available commercial sensor. The fabricated TENG sensors are used for developing an intelligent tire module to be eventually used for road testing. Several laboratory and road tests are performed to study the capability of this newly developed TENG-based sensor for tire-condition monitoring system. However the development of this sensor is in its early stage, it shows a promising potential for installation into the hostile environment of tires and measuring tire-road interacting forces. A comparative studies are provided with respect to Michigan Scientific transducer to investigate the potential of this flexible nanogenerator for TCMS. It is worth mentioning that this PhD thesis presents one of the earliest works on the application of TENG-based sensor for a real-life system. Also, the potential of commercially available thermally and mechanically durable Micro Fiber Composite (MFC) sensor is experimentally investigated for TCMS with fabricating another set of intelligent tire. Several testing scenarios are performed to examine the potential of these sensors for TCMS taking into account a simultaneous measurement from Michigan Scientific transducer. Although both flexibility and the cost of this sensor is not comparable with the fabricated TENG device, they have shown a considerable and reliable performance for online measuring of tire dynamical parameters in different testing scenarios, as they can be used for both energy harvesting and sensing application in TCMS. The extensive road testing results based on the MFC sensors provide a valuable set of data for future research in TCMS. It is experimentally shown that MFC sensor can generate up to 1.4 $\mu W$ electrical power at the speed of 28 $[kph]$. This electrical output shows the high capability of this sensor for self-powered sensing application in TCMS. Results of this thesis can be used as a framework by researchers towards self-powered sensing system for real-world applications such as intelligent tires

High Sensitive MEMS Intraocular Capacitive Pressure Sensor (Glaucoma)

الأنظمة الميكانيكية الكهرو ميكانيكية الدقيقة(MEMS) هي تقنية صغيرة الحجم تم تبنيها بشكل كبير من قبل صناعة الدوائر المتكاملة (IC) وتطبيقها على تصغير جميع الأنظمة (الأنظمة الكهربائية والميكانيكية والضوئية والموائع والمغناطيسية وغيرها). تم تحقيق الحد الأدنى من خلال عمليات التصنيع الصغيرة. مستشعر الضغط السعوي هو ببساطة جهاز من نوع الحجاب الحاجز يتم فيه تحديد إزاحة الحجاب الحاجز عن طريق قياس تغير السعة بين الحجاب الحاجز ولوحة معدنية قريبة منه. لهذا الغرض، وأجهزة استشعار الضغط داخل العين مهمة في الكشف عن وعلاج مرض عضال يسمى الجلوكوما. لتحسين حساسية مستشعر الضغط بالسعة، يتم استخدام مادة البولي سيلكون منخفضة التوتر المخدر كمادة متوافقة حيويا. الجلوكوما هو مجموعة من أمراض العيون التي تحدث بسبب ارتفاع ضغط العين (IOP). IOP هو الضغط الذي يمارسه سائل العين يسمى الفكاهة المائية (السائل الواضح داخل العين) الذي يملأ الغرفة الأمامية للعين تظهر النتائج العلاقة المحاكاة بين السعة والضغط لـ ++ clamped silicon وpolysilicon. يمكن أن نرى من الشكل أن السعة الأولية لسيليكون p ++ المشكل هي حوالي 1.81 pF تتراوح السعة من 1.81 إلى 2.162 pF للسليكون p ++ المشدد والحجاب الحاجز polysilicon، على التوالي وبالتالي فإن التغير الكلي للسعة. هذه النتيجة تبين استخدام مادة البولي سيليكون في الحجاب الحاجز حساسية عالية من السيليكون p + +.Micro Electro Mechanical Systems (MEMS) are a small-scale technology that was largely adopted by the IC industry and applied to miniaturize of all systems (electrical systems, mechanical, optical, fluidic, magnetic, etc.). Minimization has been accomplished with small manufacturing processes. A Capacitive pressure sensor is simply a diaphragm-type device in which the diaphragm displacement is determined by measuring the capacitance change between the diaphragm and a metal plate that is close to it. For this purpose, intraocular pressure sensors are important in detection and treatment of an incurable disease called glaucoma. To improve the sensitivity of the capacitive pressure sensor, low stress doped polysilicon material is used as a biocompatible material. Glaucoma is a group of eye diseases that occurs by high intraocular pressure (IOP). IOP is the pressure exerted by the ocular fluid called aqueous humor (the clear fluid inside the eye) that fills the anterior chamber of the eye The results Shows the simulated relation between capacitance and pressure for clamped ++silicon and polysilicon clamped. It can be seen from figure that the initial capacitance for clamped p++ silicon is about 1.81 pF the capacitance varies from 1.81 to 2.162 pF for clamped p++silicon and clamped polysilicon diaphragm, respectively, so the total variation of the capacitance. This result shows the use of poly silicon material in diaphragm is high sensitivity than the p++ silicon

Towards self-powered sensing using nanogenerators for automotive systems

The final publication is available at Elsevier via https://dx.doi.org/10.1016/j.nanoen.2018.09.032 © 2018. This manuscript version is made available under the CC-BY-NC-ND 4.0 license https://creativecommons.org/licenses/by-nc-nd/4.0/Harvesting energy from the working environment of vehicles is important for wirelessly monitoring their operation conditions and safety. This review aims at reporting different sensory and energy harvesting technologies developed for automotive and active safety systems. A few dominant sensing and power harvesting mechanisms in automotive systems are illustrated, then, triboelectric, piezoelectric and pyroelectric nanogenerators, and their potential for utilization in automotive systems are discussed considering their high power density, flexibility, different operating modes, and cost in comparison with other mechanisms. Various ground vehicles’ sensing mechanisms including position, thermal, pressure, chemical and gas composition, and pressure sensors are presented. A few novel types self-powered sensing mechanisms are presented for each of the abovementioned sensor categories using nanogenerators. The last section includes the automotive systems and subsystems, which have the potential to be used for energy harvesting, such as suspension and tires. The potential of nanogenerators for developing new self-powered sensors for automotive applications, which in the near future, will be an indispensable part of the active safety systems in production cars, is also discussed in this review article