Introduction to Strawbees
Explore more fun ways to program with Quirkbot and the hardware capabilities. Use it as a controller connected to the servo motor balancing a teetering, Strawbees seesaw track and balance a ping-pong ball. At the end of the lesson challenge the class to try to transport a ping-pong ball across as many tracks as possible before hitting the ground.
Materials
- Straws - x200
- 1 Legged Strawbees - x100
- 2 Legged Strawbees - x200
- Quirkbot - x10
- Quirkbot Servo Backpacks - x10
- USB Cables - x10
- Alligator Clips - x60
- Servo Motors - x10
- Ping Pong Balls - x12
- Screwdriver
- Scissors
- Computer required
Experience Level
Intermediate
Duration
Two Hours
Learning Objectives
• Express a solution in such a way that a computer - human and machine can effectively carry out for a problem.
• Dive into an introduction of the Computational Thinking process by engaging in three steps:
- Problem formulation (How does this work?)
- Solution expression (build a model)
- Solution execution and evaluation (the results and feedback of solution).
• Collaborate asa team to learn programming and build models to meet a solution to accomplish a challenge.
• Engage in a difficult problem to solve using programming as a problem-solving toolwhere the outcome may not be desireable for a lengthy period of time.
Lesson
In this lesson you will begin to engage in programming concepts where students will study the cause and effect of modifying code and the impact it makes on the Strawbees project. You will see students learn firsthand the struggles of coding and help them learn how to problem solve with unfamiliar concepts and projects that may not work for lengthy periods of time. Students will build upon previous knowledge of using Strawbees to create a base, track, and decided on how to incorporate Quirkbot as an intentional part of the project. Students can explore designing different base shapes, adjusting the track, and alter the sensitivity of the Quirkbot to make the balancing track easier or hard to use.
1. Get your students starting to think practically about how elemental balance is for all inventions. In these exercises students will learn how to assemble a simple electronically powered balance that pivots a complimenting structure on a small motor.
Ask the class, "If you stood on the tip of a mountain, what is the motion you would make?" Have your students explain or even act it out! Mention, "You would fall! But you might be able to prolong your fall by balancing yourself using your arms and legs."
2. Let your students know they will create a three dimensional structure in the shape of a pyramid, with the full use of the motor, their Quirkbot and their Strawbees. If you have an example made, display how it works. The motor will be attached to the top of the structure and pivot their “bridge” that will balance any items they choose to place on it (in this case, a ping pong ball). The motor is programmable through Quirkbot’s CODE portal so students can adjust the angle and speed at which the motor operates. Have some students work on building the Strawbees tetrahedron structure to mount the servo motor on for the track. You can have students build multiple tetrahedrons that slightly decrease in size in order for alonger track for the ball to roll down on.
3. Let your students know building the track is a process and many times the ball will fall off.
Make sure to show students how to assemble together the 2-Legged Strawbees and start by making a lot of them first before adding straws. It's important to note that the 2-Legged Strawbee's legs are slid further into each head of the other 2-Legged Strawbees. The center should not be rotating or moving around, but should be stationary. Walk around the room to check student's progress making on these.
4. Test the track to see if the ball can roll down from one end to the other. If the ball cannot, then fix the 2-Legged Strawbees and make sure the straws are not warping or are twisted between them. This might cause the ball to roll off the track before reaching the bottom. If your students are making extra tracks for the additional tetrahedra and the ball rolls down it fine, use a1-Legged Strawbee to make a friction lock from the middle of the track.
5. Fasten the Servo Mount in your student's Strawbees constructions. You can add more Strawbees connected to each other to increase the friction and pull their legs through the holes to tighten the Servo Mounts. This helps your students attach the servo easier.
When putting a straw on the Strawbee on the servo motor horn, make sure to slide it over both the Strawbees and the motor arm itself. Encourage your students to pinch the end of the Straw first before sliding it so it covers both the servo horn and Strawbee.
6. To assemble the track and base add two 1-Legged Strawbees on each end of the servo motor mount. Students will attach the Quirkbot to the servo motor once the track is carefully assembled. Advise students to carefully slip the straws onto the servo horn and 2-Legged Strawbee to the track. One side of the track must be cut in half and trimmed to attach to the middle of the track.
7. Attach the servo backpack to the Quirkbot in order to program the servo motor and connect the headers on the wire to the number 1 pins on the back. You can carefully hang the Quirkbot from the servo motor since it will be freely hanging as a touch controller.
8. Open Quirkbot CODE with the settings on Advanced so your students can see all nodes for this program. Have your students drag the following the nodes: 2 LEDs, 1 Converter, 1 Circuit Touch, 1 Servo Motor, and 1 KeyPress.
You can see an example here: https://code.strawbees.com/flow/?p=57b55be2d98853497a2ca82b
9. Challenge your class with these: "Can you pass the ball from one Balancing structure to another?" "Can you make a long, steady track going down? See what happens if the ball rolls down too fast!" "Can you program the Quirkbot to keep the ball on top without having to touch it?
Let your students take turns and attempt to carefully balance the ball onto the tracks until it reaches the end. The Ball cannot fall off otherwise they have to switch!
Resources
Internet URL: https://code.strawbees.com/index.html
Optional: Notebooks and pencils, pre-built models
Kits: Strawbees Quirkbot Coding & Robotic Kit for up to 16 projects, Strawbees School Kit with 4060 pieces.
Click to download the Strawbees PDF.