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Links & Linkages
Applications in Design & Engineering: Compound Machines Curriculum Packet
1
v2.0
Overview:In this lesson, students will learn how different types of linkages can be used to redirect or convert motion. Students will build a series of mechanisms and then work as a team to create a custom design that includes a linkage.
Click here to explore the entire Kid Spark Curriculum Library.
Learning Objectives & NGSS Alignment: Identify different types of links/linkages. Build and analyze a series of linkages. Use Kid Spark engineering materials to create a custom design.
Scientific/Engineering Practice - Developing and using models Crosscutting Concept - Systems and system models
Convergent Learning Activity:1. What is a Linkage? A linkage is an assembly of links connected by joints or pivots. Linkages can be used to change the direction of motion, convert motion, or to create mechanical advantage to make work easier.
Linkages can be any size or shape. Pictured below are a few examples of straight links and geometric shaped links that can be made using Kid Spark engineering materials.
Activity Time: 120 Minutes
Targeted Grade Level: 6 - 8
Student Grouping: Teams of up to 4 students
Additional Lesson Materials: - Teacher Lesson Plan- Student Engineering Workbook
Kid Spark Mobile STEM Lab: Young Engineers OREngineering Pathways
LinkLink
Joint
Straight Links Geometric Shaped Links
2
2. Creating Different Types of Linkages Instructions: Build and test at least two of the linkages shown below.
Lever A lever is one of the most basic types of linkages and mechanisms. A lever consists of a lever arm (link) and a fulcrum (joint). Levers can be used to change the direction of motion or to create mechanical advantage. Mechanism and machines that create mechanical advantage are extremely useful because they reduce the amount of effort needed to move or raise something. To increase the mechanical advantage in a lever, simply move the fulcrum closer to the load.
Build Instructions: Page 3
Reverse Motion Linkage In a reverse motion linkage, as one end of the linkage is pulled or pushed, the other end of the linkage reacts in an opposite direction. This linkage is comprised of five straight links, connected by four axle joints. The linkage is connected to a center support structure which guides its movement.
Build Instructions: Pages 4 - 5
Parallel Motion Linkage In a parallel motion linkage, as one end of the linkage is pulled or pushed, the other end of the linkage reacts in the same direction. This linkage is comprised of three straight links, connected by two axle joints. The linkage is connected to a support structure which guides its movement.
Build Instructions: Pages 6 - 7
90° Bell Crank Linkage The bell crank linkage transmits motion 90° by pivoting around a center fixed point. This linkage is comprised of three links that are connected by two axle joints. The linkage is connected to a support structure which guides its movement.
Build Instructions: Pages 8 - 9
Lever Arm (Link)
Fulcrum (Joint)
Effort
Load
3
LeverFollow the step-by-step instructions to assemble a lever.
1 2
1x Beams
4x Blocks
2x Half Beams
1x Single Snap Block
1x Hinge Block
3
1x Beams
2x Blocks
1x Snap-In Wheel
Lever Arm (Link)
Fulcrum (Joint)
Effort
Load
Instructions: Press down on one end of the lever and observe how the other end raises in the opposite direction. Try movingthe fulcrum closer to the load and observe how less effort isrequired to raise the load.
4
Reverse Motion LinkageFollow the step-by-step instructions to assemble the reverse motion linkage.
1 2
2x Beams
4x Blocks
3 4
3x Half Beams
1x Risers
4x Blocks
2x Single Snap Block
3x Axle Block
2x Double Snap Block
4x Single Snap Block
5
Reverse Motion LinkageFollow the step-by-step instructions to assemble the reverse motion linkage.
5 6
7
2x Block
1x Half Beam
2x Axle Block
1x Single Snap Block
4x Blocks
2x Beam
Instructions: Pull or push one end of the linkage and observe how the other end moves in the opposite direction.
6
Parallel Motion LinkageFollow the step-by-step instructions to assemble the parallel motion linkage.
1 2
2x Beams
4x Blocks
3 4
2x Half Beams
6x Blocks
2x Axle Block
2x Axle Block
4x Risers
2x Half Beams
2x Half Beams
2x Single Snap Block
7
Parallel Motion LinkageFollow the step-by-step instructions to assemble the parallel motion linkage.
5
4x Block
6
1x Half Beams
2x Axle Block
2x Single Snap Block
Instructions: Pull or push one end of the linkage and observe how the other end moves in the same direction.
8
90° Bell Crank LinkageFollow the step-by-step instructions to assemble the 90˚ bell crank linkage.
1 2
2x Beams
4x Blocks
3 4
3x Half Beams
2x Risers
1x Blocks
2x Single Snap Block
3x Axle Block
2x Double Snap Block
4x Single Snap Block
2x Axle Block
1x Mini Curved Beam
1x Risers
9
90° Bell Crank LinkageFollow the step-by-step instructions to assemble the 90˚ bell crank linkage.
5
8x Block
2x Beams
Instructions: Pull or push one end of the linkage and observe how the linkage transmits motion 90° by pivoting aroundthe center fixed point.
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Divergent Learning Activity:
Scenario: Kid Spark Engineering is currently accepting proposals for new and creative product inventions or innovations that serve a specific purpose.
Design & Engineering Challenge: Develop a new product or design that includes some type of linkage. See example below.
Specifications/Criteria: 1. Students will work in teams of up to 4 to design and engineer a new product or design that serves a specific purpose. Teams can invent something completely new or improve an already existing product.
2. Teams must work through each step of the design & engineering process to design, prototype, and refine their design. Teams will demonstrate and present their designs to the class when they are finished.
3. The product or design should include some type linkage that enables it to function correctly.
4. Teams must determine the overall dimensions (length, depth, and height) of the product or design, as well as any detailed specifications that are relevant to the design.
5. With each building component costing $2, determine the total cost of the design.
Example Idea:
Product Innovation/Invention: Extendable Gripper
Purpose: Retrieve things safely from a distance
Design Notes: The extendable gripper is a linkage comprised of six links and seven joints (axle blocks). To extend the gripper, push handles together. To retract, pull handles apart. The gripper has a maximum extension of 50 cm.
Dimensions: 22 cm x 12 cm x 6 cm (L x D x H)
Material Cost: 29 components x $2 = $58
Length - 22 cm
Height - 6 cm
Depth - 12 cm
Max Extension - 50 cm
Handle
Handle
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Challenge EvaluationWhen teams have completed the design & engineering challenge, it should be presented to the teacher and classmates for evaluation. Teams will be graded on the following criteria:
Design and Engineering Process: Did the team complete each step of the design and engineering process?
Design Specification: Did the team complete the design specification?
Team Collaboration: How well did the team work together? Can each student describe how they contributed?
Design Quality/Aesthetics: Is the design of high quality? Is it structurally strong, attractive, and well proportioned?
Presentation: How well did the team communicate/explain all aspects of the design to others?
Design Specification
Team Collaboration
Design Quality/Aesthetics
Complete/well-detailed and of high quality
Every member of theteam contributed
Great design/greataesthetics
Most members of theteam contributed
Good design/goodaesthetics
Average design/average aesthetics
Poor design/pooraesthetics
Few members of the team contributed
Team did not work together
Presentation
Points
Total Points
Proficient4 Points
Advanced5 Points
Partially Proficient3 Points
Not Proficient0 Points
/25
Grading Rubric
Complete/opportunities for improvement
Incomplete/opportunities for improvement Incomplete
Great presentation/very well explained
Good presentation/well explained
Poor presentation/poor explanation
No presentation/no explanation
Design & Engineering Process
Completed all 5 steps of the process
Completed 4 steps of the process
Completed 3 steps of the process
Completed 2 or fewer steps of the process
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Building BasicsThe following tips will be helpful when using Kid Spark engineering materials.
Connecting/Separating ROK Blocks:
ROK Blocks use a friction-fit, pyramid and opening system to connect. Simply press pyramids into openings to connect. To separate blocks, pull apart.
Connecting/Disconnect Smaller Engineering Materials:
Smaller engineering materials use a tab and opening system to connect. Angle one tab into the opening, and then snap into place. To disconnect, insert key into the engineered slot and twist.
Snapping Across Openings:
Materials can be snapped directly into openings or across openings to provide structural support to a design. This will also allow certain designs to function correctly.
Attaching String:
In some instances, string may be needed in a design. Lay string across the opening and snap any component with tabs or pyramids into that opening. Be sure that the tabs are perpendicular to the string to create a tight fit.
2cm18cm
9 Openings
Measuring:
The outside dimensions of a basic connector block are 2 cm on each edge. This means the length, depth, and height are each 2 cm. To determine the size of a project or build in centimeters, simply count the number of openings and multiply by two. Repeat this process for length, depth, and height.
2cm
2cm
4cm 4cm
4cm
55-02148-200
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