Grade Level:
9-12
Prerequisites:
9th grade general math and science
Concepts Addressed:
In this unit, students will learn about the different types of lifting mechanisms and how they work. Engineering topics will include degrees of freedom, shock load, joint loading, joint speed, elevators, linkages, and passive assistance.
Learning Objectives:
- The students will be able to differentiate the three degrees of freedom that are presented in the beginning of the unit.
- The students will be able to demonstrate the correct use of the calculations needed to choose a gear reduction
- The students will be able to distinguish between the use of a linkage system and a multi-state elevator in manipulator design.
- The students will be able to explain how passive assistance can improve a robot design.
STEM Connections:
The major physics concept of degrees of freedom
The math components necessary to calculate the approach of a rotating joint
Materials Needed:
- Unit Guide
- Paper
- Pencils
- Rulers
- Internet Access
- Dictionaries
- VEX Robotics Kit
- Computers with Autodesk Inventor
- Storage containers
- Online Resources
Key Terminology:
- Object manipulators
- Lifting mechanisms
- Degrees of freedom
- First degree of freedom
- Second degree of freedom
- Third degree of freedom
- Shock load
- Joint loading
- Joint speed
- Mechanical advantage
- Factor of Safety
- Elevator
- Actuation
- Linkages
- Passive assistance
Day to Day Lesson Plan:
Day 1:
Provide an introduction on the basic principle of degree of freedom. Have the students conduct research of places where the three different degrees of freedom are found in their community.
Day 2:
Begin with the material on rotating joints up through the calculations on gear reductions at a rotating joint.
Day 3:
Review calculations on Approach 1 and Approach 2
Day 4:
Begin with the material on elevators and work through information on linkages. Students can find examples of linkage systems in common objects, tools and construction.
Day 5:
Begin with a presentation on the material covering the design of a lifting mechanism and work through the information on passive assistance. Students can make sketches or use Autodesk Inventor to create some simple designs to illustrate the different types of lifting mechanisms.
Day 6:
Introduce the Design Activity and provide time for the students to complete the brainstorming portion of the activity.
Day 7:
Continue with the design activity. Check to see that students are on task and that they are completing the appropriate calculations and making entries into their engineering notebook.
Day 8:
Have students present their designs to their classmates for peer review.
Day 9:
Allow additional time for students to make changes to their designs based on the peer review.
Day 10:
Allow for additional practice on calculations, design activity and concept review.
Day 11:
Evaluation of Engineering Notebook and Design Activity.
Engineering Notebook “Seed Questions”:
- Explain how the degrees of freedom will allow you to design a robot that is able to transfer motion as it manipulates game objects.
- Explain how a linkage system allows a robot to score on a high goal in a game situation.
- Explain how passive assistance can provide your robot with a mechanical advantage.