Notes for Science Measurement and Coding Workshop
This workshop will be fun and informative. We don't expect to cover all this material in one meeting, but this will be a guide to further exploration.
Today, you will learn a bit of coding and how it can be used to enliven and deepen your classes.
Overview
This workshop introduces the use of sensors, simple coding and simple materials to perform scientific experiments and explorations. We will use the Make!Sense sensor interface board and sensors to collect and transmit data to a computer, and use the simple Scratch programming language to collect and display data. We will also look at other languages like Processing, and other apps including Plot!Sense, which is free with Make!Sense, importing data into Excel, etc.
Workshop Outline
Introduction to Make!Sense, sensors, software. Strengths and limitations. Why use Scratch? When use Plot!Sense or other?
Note: Make!Sense is also very effective in "makerspace" and invention curricula.
Demonstration of an experimental setup, measurement, graphing, exporting. Quick start: heartbeat
Make!Sense Scratch "studio" with lots of code examples is here
Introduction and practice with Scratch: heart rate variation of different people, heart rate increase from exercise, horse race
Explanation of keystroke and datastream modes for the Make!Sense board, Scratch and ScratchX
Description of common sensors. On/off and variable range
Discussion of Plot!Sense. Show PlotSense with thermistor, heartbeat, two breakbeams Plot!Sense download
Distribution of equipment and individual experimentation
Sharing of results, suggestions for use and improvement of techniques and experimental design
Make!Sense:
Make!Sense boards
Any analog sensor can be used with Make!Sense, either resistive or voltage output. Up to 8 sensor channels can be used. Make!Sense can be used in "keystroke" mode or datastream mode.
Configurator and Visualizer software displays sensor values in real time, as well as the keystroke mappings, Configurator/Visualizer download.
For science experiments there is also a set of very detailed curriculum guides on this website, farther down under the Make!Science menu tab.
Some Experiments: timing and heart rate and similar on/off sensors work well and simply with Scratch
Scratch results vs Plot!Sense results. Demo heartbeat. Demo analog sensors with Plot!Sense
Demonstrations of Scratch with heartbeat and breakbeam sensors. Examine the code.
--Using keystrokes to start and stop Scratch Timer Attach a sensor using Make!Sensor to generate keystrokes: first breakbeam then heartbeat. Modify code to show only the value, not the word "timing"
--Saving data in a list Trigger on "A" key, adds each time interval to a running list, use with pendulum or heartbeat
--Timed Heartrate, Using Math to modify data, elapsed heartbeat interval to BPM (another approach)
--My Heart is Racing Two players compete in a heartrate-controlled horse race
--Video of teachers in a bone-shaking, heart pounding competition
--Exporting data from a list in Scratch, and from Plot!Sense
Experiments:
Gravitational Constant
Falling ball, meter stick, tape, two breakbeam sensors, half-open door
"Simplest Scratch Elapsed Time Two Sensors" on the Make!Sense Scratch Studio
Velocity:
Cardboard ramp, toy car or ball, meter stick, breakbeam sensors
Acceleration:
Slow Roller: CD, faucet washer, dowel, meter sticks, breakbeam sensor(s).
Bicycle Wheel: upended bicycle, tape, breakbeam sensor
Pendulum dynamics:
Ball, string, tape, meter stick, breakbeam sensor
Heart Rate:
Heart rate sensor
For analog continuous values, it's best to use Plot!Sense or Processing
However, it's also possible to set Make!Sense in keystroke mode to report 8, 16 or 32 values for an analog sensor
Temperature:
Air temperature variations: thermistor sensor
Liquid temperature: ice water or boiling water, submersible temperature sensor
Evaporation of water:
Air and moisture sensors, sponge or paper towel, fan or sunlight
DIY
Use the Make!Sense alligator clip connector to make a voltage divider
Thermistor or photocell on one leg, and fixed resistor on the other
White cable is "signal" so sensor can go between white and black
Fixed resistor can go between white and red
Data Gathering
Scratch:
Coding a software stopwatch using keypresses in Scratch
Replacing the keypresses with a sensor
Capturing sequential readings, displaying, storing and exporting them
Data Manipulation
Determining the consistency of sensor readings in a given experimental setup: repeat the same data gather many times
Recognizing and discarding outliers
Averaging a number of data values
Data Display
Simple Graphing of data in Scratch
Time Graphs
Bar graphs
Changing the sampling rate in Plot!Sense
When to use Scratch, Plot!Sense, Excel