November 30, 2010

1. Students will solve the problem of designing and building a cam toy based on the operation of a cam mechanism.

2. As students take notes, they will be completing step 3&4 of the design process.

DESIGN PROCESS

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1. From design process steps handout, check items that are checked on the screen. They require a response for turning in your design proposal.

• Next, AFTER YOU GIVE A RESPONSE (not now), draw a line through that item. As in the example below.

Design Process

a. What must your solution accomplish?

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Gather information – obtain background information needed to begin developing solutions to the problem/situation

a. What specific information do you need to know prior to designing your solution?

b. What criteria/constraint details must you be informed about?

Steps 3 & 4 – Brainstorm/ Research/ Generate Ideas

Outcome: Sentences, Paragraphs, Lists, Charts U3b-L7

•Draw checks only, now as they appear on screen.•We draw a line through them after taking notes as a response.

NOTE:

Note-taking in FOT

• At Poly we train you for two things:• Success in college• Success in the world

• Do not copy every word – it won’t be possible.

• Capture the main ideas and key details.

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A CAM changes the input motion, which is usually rotary motion (a rotating motion), to a reciprocating motion of the follower. They are found in many machines and toys

Have you ever looked closely at a simple mechanical toy ? If you have the opportunity to study one closely you will see that it is made up of mechanisms, usually including CAMS. Can you name any mechanical devices that use cams as part of its movement?

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Below is a mechanical toy based on a CAM mechanism. As the cam is turned the top part of the egg shell lifts to reveal a face.

The basic construction of the toy is also on the left. The ‘flat’ follower moves upwards and downwards as the eccentric cam rotates.

Although the design is simple it must be made accurately or the mechanism will stick. (Look at common faults slide). U3b-L7

The diagrams show a typical CAM, mechanical toy. The follower has jammed as the profile rotates in a clockwise direction. There are two possible reasons/faults that lead to this problem;

1. The slides are too far apart, allowing the follower to jam as the profile rotates.

2. The shape of the follower means that the movement of the mechanism is likely to jam or at best, move roughly rather than smoothly. U3b-L7

The diagrams show a typical CAM, mechanical toy. The follower is working properly as the profile rotates in a clockwise direction. There are two possible reasons it works properly;

1. The slides are not too far apart, allowing the follower to move at 90 degrees as the profile rotates.

2. The shape of the follower does not change which means the movement of the mechanism will not jam, move smoothly rather than roughly. U3b-L7

A CAM has two parts, the FOLLOWER and the CAM PROFILE.

The shape of the cam is called the PROFILE.

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Cams can be shaped in any number of ways and this is determined by the way the follower is to move. Examples of various cam profiles can be seen below.

CAM PROFILE

CAM PROFILE

CAM PROFILE

CAM PROFILECAM PROFILE

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Gather information – obtain background information needed to begin developing solutions to the problem/situation

a. What specific information do you need to know prior to designing your solution?

b. What criteria/constraint details must you be informed about?

Steps 3 & 4 – Brainstorm/ Research/ Generate Ideas

Outcome: Sentences, Paragraphs, Lists, Charts U3b-L7

1. Now, draw a line through the design process item(s) on your design process handout. As in the example below.

1. From design process steps handout, check items that are checked on the screen. They require a response for turning in your design proposal.

WE WILL NOT RESPOND TO DESIGN PROCESS STEPS

1, 2, 5, 6, & 7 DURING CLASS. THIS MUST BE DONE FOR HOMEWORK. Use description handout and your notes for accurate and adequate responses.

2. AT HOME, AFTER YOU GIVE A RESPONSE ( at home

not now), draw a line through that design process item. As in the example below.

Design Process

a. What must your solution accomplish?U3b-L7

1. Describe the situation that needs a technological solution

a. What must your solution accomplish?b. What is the need or desire?

Step 1 – Defining the Problem

Outcome: Sentences, Paragraphs, Lists U3b-L7

• Draw checks now as they appear on screen.• AT HOME, draw a line through the item after you give a response.

NOTE:

2. Establish the criteria and constraints under which the solution must operate

a. What are solution requirements (criteria)?b. What are the limitations on the solution

(constraints)?

Step 2 – Identifying Criteria/Constraints

Outcome: Sentences, Lists, ChartsU3b-L7

NOTE:•Draw checks now as they appear on screen.• AT HOME, draw a line through the item after you give a response.

5. Develop possible solutions to the problem/opportunity

a. Come up with at least 3 solutions to the problems you must solve. This may be done in the form of 3 General sketches.

b. Does each satisfy the criteria and fit within the constraints?

Outcome: Sentences, Lists, Charts, Sketches

Step 5 – Exploring Possibilities

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NOTE:•Draw checks now as they appear on screen.• AT HOME, draw a line through the item after you give a response.

6. Isolate, refine, and detail the best solutiona. Modifyb. Integrate componentsc. Make the sketch Improved and Detailed

Outcome: Sentences, Lists, Charts, Sketches

Step 6 – Select an Approach (One of your sketches)

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NOTE:•Draw checks now as they appear on screen.• AT HOME, draw a line through the item after you give a response.

7. An explanation of your final designa. Detailed drafted drawingsb. Steps to make itc. Explanation of how it satisfies all criteria and

constraints

Outcome: Sentences, Lists, Charts, Sketches

Step 7 – Develop Design Proposal

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NOTE:•Draw checks Now as they appear on screen.• AT HOME, draw a line through the item after you give a response.

8. Make it!

Prototype will be tested

Outcome: Sentences, Lists, Charts, Sketches

Step 8 – Make Model/Prototype

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NOTE:•Draw checks Now as they appear on screen.• AT HOME, draw a line through the item after you give a response.

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HOMEWORK

2. To begin step 8 (make a prototype) you must get your proposal (steps 1, 2, 5, 6 & 7) passed first by your teacher. BE READY TOMORROW WITH PROPOSAL DONE.

COMPLETE STEPS 1, 2, 5, 6, & 7 Use description handout and your notes for accurate and adequate responses. AT HOME, AFTER YOU GIVE A RESPONSE ( at home not now), draw a line through that design process item.

1.