|
 |
| STEM II
|
|
|
|
| STEM - represents SCIENCE, TECHNOLOGY, ENGINEERING AND MATHEMATICS. STEM II is required for all 8th graders. There are two seperate courses taught inside of STEM II; they are automation of robotics and the magic of electrons. |
Activity 2.2
October 29, 2009 |
 |
Activity 2.2– Mechanical Gears
Purpose
What do a bicycle, eggbeater, and Polaris pool cleaner have in common? They all use gears to increase, decrease, or redirect power. Gears come in all sizes. A mechanical wind-up watch has very small gears, while the gears used to lift a bridge to allow ships to pass underneath are huge. There are different gear configurations that are used for different purposes.
In this activity, you are going to build ten different gear assemblies and observe how they are used. This information is going to come in handy when your class designs and builds its automated factory assembly line.
Equipment
· Engineering notebook
· Fischertechnik base plate
· Fischertechnik parts
· Digital camera
Procedure
Complete the following assemblies using the Fischertechnik kit provided. You may vary from the original design as long as the finished product still performs the same desired outcome. Have your teacher initial your checklist after you complete each assembly, and then answer the questions beside the diagram in your engineering notebook before going on to the next mechanism.
If you are provided with a digital camera, take pictures of each of your completed assemblies and place them in your notebook.
Universal Joint
What is the angular range between the input shaft and the output shaft in which this mechanism will work?
Is the speed increased, decreased, or constant?
Is the torque increased, decreased, or constant?
What is the speed ratio of the input shaft to the output shaft?
Is the flow of power reversible? [Can you make the input shaft turn by turning the output shaft?]
Is the direction of travel reversible? (Does the mechanism still work if the cranks is turned the opposite direction?)
List an example where this mechanism might be used. For help, go to www.askjeeves.com and use keywords: universal joint.
Bevel Gear Assembly
What is the angle of the input shaft compared to the output shaft?
Is the speed increased, decreased, or constant?
Is the torque increased, decreased, or constant?
What is the gear ratio?
Is the flow of power reversible? [Can you make the input shaft turn by turning the output shaft?]
Is the direction of travel reversible? (Does the mechanism still work if the cranks is turned the opposite direction?)
List an example where this mechanism might be used. For help, go to www.howstuffworks.com and use keyword: bevel gear.
Crown and Pinion
What is the angle of the input shaft compared to the output shaft?
Is the speed increased, decreased, or constant?
Is the torque increased, decreased, or constant?
What is the gear ratio?
Is the flow of power reversible? [Can you make the input shaft turn by turning the output shaft?]
Is the direction of travel reversible? (Does the mechanism still work if the cranks is turned the opposite direction?)
List an example where this mechanism might be used. For help, go to www.howstuffworks.com and use keyword: gears.
Rack and Pinion
What is the type of input movement? (Rotary, Reciprocating or Linear)
What is the type of output movement? (Rotary, Reciprocating or Linear)
What distance does the rack move with one revolution of the crank?
If the diameter of the pinion gear were increased, would the rack move a shorter or longer distance?
Is the flow of power reversible? (Can you make the input shaft turn by turning the output shaft?)
Is the direction of travel reversible? (Does the mechanism still work if the cranks is turned the opposite direction?)
List an example where this mechanism might be used. For help, go to www.howstuffworks.com and use keyword: rack & pinion.
Worm and Wheel
What is the angle of the input shaft compared to the output shaft?
Is the speed increased, decreased, or constant?
Is the torque increased, decreased, or constant?
What is the gear ratio?
Is the flow of power reversible? [Can you make the input shaft turn by turning the output shaft?]
List an example where this mechanism might be used. For help, go to www.howstuffworks.com and use keyword: worm gear.
Leadscrew
What is the type of input movement?
(Rotary, Reciprocating or Linear)
What is the type of output movement?
(Rotary, Reciprocating or Linear)
How many revolutions of the crank are needed to move the screwblock 1 inch?
Is the flow of power reversible?
[Can you make the leadscrew turn by pushing the screwblock?]
Which is increased in the output? Force or speed?
Is the direction of travel reversible? (Will the mechanism still work if the crank is turned in the opposite direction?)
List an example where this mechanism might be used. For help, go to www.howstuffworks.com and use keyword: leadscrew.
Cam and Follower
What is the type of input movement? (Rotary, Reciprocating or Linear)
What is the type of output movement? (Rotary, Reciprocating or Linear)
How many times does the follower move up and down with one revolution of the crank?
Is the flow of power reversible? [Can you make the crank turn by pushing the follower?]
List an example where this mechanism might be used. For help, go to www.howstuffworks.com and use keyword: camshaft.
Simple Gear with Idler
What is the position of the input shaft compared to the output shaft?
Is the speed increased, decreased, or constant?
Is the torque increased, decreased, or constant?
What is the gear ratio?
Is the flow of power reversible? [Can you make the input shaft turn by turning the output shaft?]
Compare the direction of travel between the input and output gears.
Predict what the direction of travel would be between the input and output gears if the idler gear is eliminated from the mechanism.
List an example where this mechanism might be used. For help, go to www.howstuffworks.com and use keyword: gears.
Pulley and belt
What is the position of the input shaft compared to the output shaft?
Is the speed increased, decreased, or constant?
Is the torque increased, decreased, or constant?
What is the input to output ratio?
Is the flow of power reversible? [Can you make the input shaft turn by turning the output shaft?]
Does the input shaft turn in the same direction as the output shaft?
List an example where this mechanism might be used. For help, go to www.howstuffworks.com and use keyword: pulley.
Crank and slider
The input to this system is what type of motion? (Rotary, Reciprocating or Linear)
The output of this system is what type of motion? (Rotary, Reciprocating, or Linear)
How far does the slider move with each revolution of the crank?
If the diameter of the crank gear were increased, would the slider move a shorter or longer distance?
Is the flow of power reversible? (Can you make the crank gear turn by pushing the slider?)
List an example of where this mechanism might be used. For help, go to www.howstuffworks.com and use keyword: crank and slider.
Conclusion
1. Which gear assemblies increased speed?
2. Which gear assemblies increased torque?
3. Which gear assemblies allow the reversal of power?
Mechanisms Checklist
Mechanism
Assembly
Summary Chart
Universal Joint
Bevel Gear
Crown |
 |
Activity 1.4 Engineering careers Webquest (homework)
Due Date: October 2, 2009 |
|
Purpose
It is not too early to start thinking about the world of work. Over 20,000 different job titles exist in the U.S. today, and by the time you join the work force, that number will have increased exponentially. Many of the jobs you will be applying for haven’t even been created!
Engineering offers more career options than any other discipline. It’s a profession that can take you from the depths of the ocean to the far reaches of outer space, from within the microscopic structures of the human cell to the top of the tallest skyscrapers. Whether it’s cell phones, digital cameras, DVD’s, or facial recognition devices that can pick out a terrorist in a crowded football stadium, engineers are behind almost all of today’s exciting technology. Engineers are problem solvers who search for quicker, better, and less expensive ways to use the forces and materials of nature to meet today’s challenges.
Engineering students have their pick of many fields. From electrical to civil to aeronautical to biomedical, every discipline within engineering will lead to an exciting and rewarding career.
In this activity, you will research one type of engineering and report back your findings to your class using a PowerPoint presentation.
Procedure
1. From the list below (Examples of Types of Engineers), select an engineering career to research. Check with your teacher about your selection.
Examples of Types of Engineers:
· Aerospace Engineer
· Agricultural Engineer
· Architectural Engineer
· BioEngineering / BioMedical Engineer
· Chemical Engineer
· Civil Engineer
· Computer/Software Engineer
· Electrical Engineer
· Environmental Engineer
· Industrial Engineer
· Mechanical Engineer
· Metallurgy and Materials Engineer
· Mineral and Mining Engineer
· Nuclear Engineer
· Ocean Engineer
· Transportation Engineer
2. You will use available resources to research an engineering career and create a PowerPoint® slide show. You may add additional information if you wish. You should take notes in your engineering notebook. The slide show should include the following information
· Slide #1 – Title Page/Career name, your name, picture of someone working in this career
· Slide #2 – Job Description
· Slide #3 – Work Tasks
· Slide #4 – Necessary Skills and Abilities
· Slide #5 – Education/Training required (including college/technical school programs)
· Slide #6 – Wage Information
· Slide #7 – Job Outlook (% of growth)
· Slide #8 – Why this career does/does not appeal to you
Some websites that will be helpful for your research are:
· ASEE Engineering K-12 Center: http://engineeringk12.org
· US Department of Labor – Bureau of Labor Statistics: http://www.bls.gov/oco/home.htm
· American Institute of Aeronautics and Astronautics: http://www.aiaa.org
· New York State Career Zone: http://www.nycareerzone.org/
3. After listening to your classmates’ presentations and your own research, complete the conclusion questions.
Conclusion
1. What is the most interesting type of engineer?
2. What is the most interesting task an engineer performs?
3. What one thing would make you more interested in becoming an engineer?
4. What would be the hardest thing about being an engineer?
5. What is the job outlook for engineers?
|
|
Lesson 1.1a Historyof Robotics (homework)
Due Date: September 25, 2009 |
|
Activity 1.1a History of Robotics
Purpose
Most people think that robots are mechanical people of the future. Use the website below to investigate our history with robotics and what our future might look like.
Equipment
· History of Robotics handout
· Computer with Internet access
· Pencil
Procedure
Go to the following website and read through the sections, answering the questions below.
http://www.thetech.org/exhibits/online/robotics/universal/index.html
Feel free to watch any of the videos on the website while reading through the pages.
1. List five tasks that robots can currently perform:
2. Approximately how long have we been using robots? ____________________
3. It is thought that Homer, the ancient Greek poet, described the first metallic helpers for which Greek god?
4. When did Leonardo da Vinci draw plans for a mechanical man?
5. What events spurred the development of robots in the 1950s and 60s?
6. What was the first product of robotic manufacturing in 1959?
7. What two characteristics differentiate a robot from a machine?
8. When, where, and what was the first use of the word robot?
9. What percentage of robots work in factories?
10. What function do more than half of robots perform?
11. What accident in 1986 demonstrated a clear need for a robot to go where humans couldn’t?
12. How are robots used in microsurgery?
13. What is the name of the rover that investigated the surface of Mars in 1997?
14. How long does it take for commands from Earth to reach a rover on Mars?
15. Where else, besides space exploration, can robots go that humans cannot?
16. What happened in 1994 in Alaska?
17. What is unique about Nomad?
18. What was the name of the vehicle that was a predecessor in the early 1970s to the Nomad as a somewhat autonomous vehicle?
19. What is a degree of freedom?
20. How many degrees of freedom does a robot need to reach any point in space?
21. One of the most common types of robotic sensors is the light sensor. One of the simplest uses of the light sensor is for ___________________.
22. What is one of the greatest challenges for robotic engineers?
23. List five other types of sensors.
24. One way to create artificial intelligence is to use what kind of logic?
25. What are two other approaches to artificial intelligence?
26. At what year is it expected that robots will reach the equivalent of human intelligence?
27. What are the three Laws of Robotics as written by Isaac Asimov in the 1940s
|
|
|
Lake Middle School
MICHAEL KEALY
|
|
|
|
|
