Students investigate the behavior of pressure and heat sensitive piezoelectric films. They use these materials to make a coin-counting and other smart sensing devices.
By incorporating everyday materials into science lessons, the Materials World Modules (MWM) program at Northwestern University has found the solution to getting students excited about learning science while helping teachers meet national and state education standards.
The modules are easy to organize and inexpensive to run. They can be incorporated into any science class because of the breadth of subjects covered in the Activity and Design Project sections. Each module is a supplemental science unit that takes 1-3 weeks of class time (approximately 10 hours) to complete.
MWM will give students an opportunity to understand the world around them in a way they have never experienced before. The modules promote an awareness of the roles science and technology play in society and guide students to take increased control of their work.
Activity 1: Evading Motion Detection
Students observe the stimulus and response of a commercial piezoelectric motion detector and are challenged to evade the detector.
Activity 2: Taking a Tour of Some Sensors
Students observe, describe, and hypothesize about properties of various sensors. For each sensor, they record the stimulus detected, the output, the system's construction, and possible applications.
Activity 3: Making a Microphone
Students assemble, operate, and evaluate a piezoelectric microphone system.
Activity 4: Exploring the Piezo Effect: The Inside Story
Students construct models of the PVDF monomer and polymer. Then they apply what they've learned to interpreting experimental results relating stress to voltage response in PVDF film.
Activity 5: Measuring Piezoelectric Response
Students investigate the piezoelectric and pyroelectric responses of PVDF film and summarize the relationship between force and heat and the film's voltage response.
Design Project 1: Designing a Coin Counter
Students design, construct, test, and redesign a smart-sensor coin counter using PVDF. They are challenged to distinguish among coin denominations using the voltage response of PVDF film.
Design Project 2: Designing a New Sensor
Based on what they have learned about PVDF, students devise an innovative use for PVDF film in a smart-sensor system. They design, construct, test, and redesign a smart sensor that meets a need in today's world.
Connecting to Your Curriculum
Materials World Modules are simple to organize and inexpensive to run. They are designed to be easily incorporated into any middle school science or high school science lab or lecture course. The chart below lists the subjects covered in the Activities and Design Projects sections of this module.
Physics & Physical Science
Earth & Space Science
Biology and Life Science
Heat Seeking Rattler
A rattlesnake can easily strike at a motionless person in a pitch-dark room.
- What kind of sensors must the animal have to detect a person when neither sight nor sound are available?
- How does Wien’s law show you how the snake can find its victim?
Solutions and Clues in Smart Sensors Module.