Abstract- Piezoelectric sensors have been used in various forms for energy harvesting using vibrations, repetitive strikes, and bending of structures. This paper will discuss the use of piezoelectric materials within a Ten80 remote-controlled car tire to harvest power that can be used for recharging the battery. The methods used to test the amount of energy produced are compared based on the voltage required to light a blue LED. 

Introduction - Flawless Female Engineers is an all-female Ten 80 racing team. Our mission statement is to increase the number of women in the fields of science, technology, engineering, and math who are actively involved in their communities. Last season our team began to explore piezoelectricity, which has helped us collect the research project of applying real-life implications to the Ten80 car. In conversation, we started talking as a team and only a few members knew of piezoelectricity. We recognized that this topic is rarely discussed amongst our generation and to effectively increase awareness of the STEM field this research would be necessary. Ultimately, the goal is to learn more about the Ten80 car and how the usage of the mechanical stress of the piezoelectric sensor can generate energy to charge the battery. In future work, our team would like to know more about how the rate of speed impacts the rate that the batteries of the Ten80 car would charge using the piezoelectric sensors. 

History - The origin of the word Piezoelectric stems from the word piezein, which is defined as a squeeze or pressing of something and piezo means to push. (Johnson Electric Company, n.d) In the early 1880's two brothers, Pierre and Jacques Curie, French physicists, concluded a demonstration testing the relationship between solid materials like crystals/ceramics and actual crystallography (the atoms, ions, and or molecules of a crystal structure found under a microscope) testing the electric charge of the crystals when mechanical stress is applied. (Piezo Systems, n.d). 

Implemented In the Real World - In relationship to the Automotive Industry, piezoelectric sensors can be used in two ways, directly and indirectly. Often, the sensors are incorporated into manufacturing equipment for cars specifically things that contribute to the accuracy and precision's of fuel economy, safety, and connectivity - ultimately contributing to the performance of the vehicle. For example, the sensors can be incorporated to aid into how and where to aim the headlights of a car to the process of positioning parts for installation. In small cars and SUVs, the industry is dedicated to add more compact sensors for the improvement of vehicles and parts to increase the fuel mileage. ( Piezoelectric Automotive, n.d) The most common usage of piezoelectric sensors are found in tires. According to, Sensors Mag, the National Highway Traffic Administration made it a requirement that manufacturers producing cars and SUVs since 2008 must have a TPMS (Tire Pressure Monitoring System). This can be placed in cars two ways, often both can be monitored from the dashboard of a vehicle - yet one is more reliable than the other. The more reliable and accurate placement of the piezoelectric sensors is in the headlights of  Both serve to notify the driver when the tire pressure has is dropped below 25% of the average tire pressure which is 30-35 PSI. (Bridgetown Tire, n.d.). In terms of the future, the automotive industry plans to utilize piezoelectric sensors and control signals to produce energy for a more energy-efficient automotive experience. Piezoelectric materials will play an essential role in the industry as it is moving towards complete autonomous vehicles. According to the CEO of Audi, Scott Keogh, a major German automobile company, predicts that the first driverless car will be on the market by 2020. 

Arduino - In this research experiment, an open source electric platform known as Arduino will be utilized. An led blink circuit will be used to indicate the when the sensor is triggered by the tires of the Ten80 car/mechanical stress applied. This circuit consists of: jumper wires, resistors, LEDs, Breadboard, and rails. (seen in attachments) Once the circuit is built, the Arduino micro-controller will be connected to the computer, and  the blinking of the LED which will be recorded from the computer via the code provided. (Because Learning, n.d.) 

Hypothesis or Essential Question - Can the Ten80 car tire apply sufficient mechanical stress to a piezoelectric sensor to charge the car’s battery? 

Materials 

- 3-pack 27mm Piezoelectric sensors 

- Ten 80 Car 1/10 Scale

- Ten 80 Car remote control 

- Ten80 Battery (7.2V 2000mAh) (6.2V)

- Car stand Mount 

- Graph Paper or Excel Program (to record the data)

- Camera (to document the procedure / setup)

- Arduino Application Program 

- 1 Multimeter 

- Breadboard

- Resistors 

- USB Cable

- Redboard for Arduino

- Jumper Wires 

- Small LEDs

- Computer (Arduino software must be installed)

- Zip tie 

- Procedure

- Find a flat surface to conduct the experiment. 

- Take out all the materials that you will need for the project. 

- Use the car’s mount to balance the car to prepare for testing. 

- Download the Program Arduino 

- Create four plastic flaps to place around your tire and then place the sensor around the tire. 

- Using the program Arduino to test how frequent the sensor is touched. (indicated by an LED light) 

- Document data and analyze them to create a conclusion.  

Results (Data) - From our test we have concluded that piezoelectric sensors can produce enough power to recharge a Ten80 battery. We were able to place a zip tie onto the car and we ran it at full speed. We then connected the piezoelectric sensor to the zip tie and were able to accurately get a reading on how much power we could generate. We used a blue LED, which requires 3.2-4.0V to emit light. 

Conclusions - Our hypothesis for this project was, can the Ten80 car tire apply sufficient mechanical stress to a piezoelectric sensor to charge the car's battery? Through our research, we found that using Piezoelectric sensors is an effective way to generate electricity. With our Piezoelectric sensor we were able to turn on a blue LED light and generate 3.2V-4.0V. A zip tie was used to create mechanical stress on the piezoelectric sensor.  The piezoelectric sensor was able to connect to a point on the tire through the zip tie. Our data shows that a piezoelectric sensor would be sufficient in charging a Ten80 battery. Through our research and experiment we have concluded that connecting the piezoelectric sensor to the car tire can produce enough energy that will recharge the battery. Through this project we faced many trials. The hardest trial that we faced was trying to figure out an efficient way to get the piezoelectric sensor to contact the car tire. Another trial that we faced was getting an accurate reading from the voltage meter. In future work, we plan on experimenting with capacitors and voltage multiplication circuits to increase the rate that the Ten80 battery will charge. Piezoelectric energy is efficient and Earth friendly. Piezoelectric sensors will help take the world to the future and beyond.