Instructional Guide Technological Systems: Creating Mechanical Toys

During this unit you are going to: Design, build, test and make improvements to your designs. Explore simple machines and linkage mechanisms. Design a toy that uses simple machines and linkage mechanisms create movement.

Simple Machines LEVER WEDGE INCLINED PLANE SCREW WHEEL AND AXLE PULLEY

Levers Class 1 Lever Effort Fulcrum Load Effort Load Fulcrum Class 2 Lever Load Effort Fulcrum Class 3 Lever The fulcrum (pivot) is between the effort and the load. The load is between the effort and the fulcrum (pivot). The effort is between the load and the fulcrum (pivot).

Pulleys and Gears Speed of Driven Gear = Speed of Driver Gear x Teeth in Drive Gear Teeth in Driver Gear Speed of Driven Gear = 240 RPM x 12 8 = 360 RPM

Mechanisms and Linkages

Mechanisms and Linkages Definitions Fixed Point - a point that remains stationary, but links can rotate about that point. Pivot Point - point can move and link can also rotate about the pivot. Slider - holds links to back and forth movement without rotation. Sliders

Design Challenge You are a toy designer who is familiar with the Engineering Design Process. You have been asked to use this process to design, build, and test a safe toy that incorporates simple machines and linkage mechanisms.

Step 1 – Identify a challenge What is the design challenge? What limitations are given? What are the constraints?

Step 2 – Explore Ideas Sketch ideas for the new toy. Refine the best idea and label the parts. √ Identify a challenge

Step 3 – Plan and Develop √ Identify a challenge √ Explore Ideas Brainstorm ideas for improving the toy. List the materials that are needed to make the prototype. Build the prototype.

Step 4 – Testing and Evaluating √ Identify a challenge √ Explore Ideas √ Plan and Develop Have at least three students test the toy’s operations and record the results. Ask the students: Why would this toy be safe or unsafe? What would be fun about playing with the toy? What age child would play with the toy and why?

Step 5 – Presenting the Solution √ Identify a challenge √ Explore Ideas √ Plan and Develop √ Testing and Evaluating Prepare a presentation containing: A sketch of the design with all the parts labeled. The design challenge and design constraints. A discussion on how the design was developed and tested. Use of the prototype and how it works. Answer specific questions. The feedback from the testers and how your team would redesign.

Conclusion Compare all of the team toys. Discuss final designs with the class. Likes and dislikes of toys. Best design. Changes that could be made on the toys. Have students bring in and present toys that include simple machines and have linkages.