PrinciplesFall09


1-20-10

Your midyear exam is at the link below. You will use the computer to do the exam in word or Open Office. When you are done, print it and hand it in.  Raise your hand if you have any questions.

Right click on this link and choose SAVE AS:  Midyear Exam

Open the file with Word or Open Office

 

Picture of Mendo Base

 

This has been a great semester! Thanks for your enthusiastic participation in class.

 

Continuing study in Technology at DHS

Courses

You might enjoy these courses:

 

After school

Middle School robotics team

This spring, we are starting up an underwater robotics team at the middle school. If you would like to help as a mentor, meet with Mr. Connors on Friday after the exam.  We will meet on Fridays at the middle school.

After school projects

So now you know how do do lots of interesting stuff. Come by in the afternoon to create some great personal projects.

 

1-15-10

PrinciplesProjectsF09

 

Solar installations

Each cell costs $1.50, you will need a total of four.

Cells are extremely fragile, be very careful and gentle with them.

 

We will need to do a few things to them to have them work on the motors.

 

Add Tabs

On the back of the cell is a spot of solder

cut a piece of ribbon wire so that it is about 2 inches.

tin the ends of the wire with solder

solder the ribbon to the back of the cell

Do this to two cells at a time for a total of four

 

Pair up the cells.

Hook the tabs of the front of one cell to the back of the other cell.

Solder the front tab of one cell to the back tab of the other cell.

 

Attach the cell pairs to the rotor block

Use double stick tape on the opposite sides of the block to hold the cells in place.

Do this to two cells at a time.

Once the cells have been secured in place, run a length of clear adhesive tape all the way around the block to hold them in place.

When one pair is complete, you can test it for conductivity.

You should have conductivity between the wrap wire and the cells.

If you test the other wrap wire, it should not have conductivity to the wrap wire you have just soldered to the cells.

 

Attach the wrap wires to the motor

make sure the ends of the wrap wire have been sanded clean with sandpaper.

You should be able to see the copper of the wire for about a half inch.

Wrap the copper wire around the soldered pair of tabs

Heat the connection and let the wrap wire into the solder

 

 

1-14-10

 

Solar installations

Each cell costs $1.50, you will need a total of four.

Cells are extremely fragile, be very careful and gentle with them.

 

We will need to do a few things to them to have them work on the motors.

 

Add Tabs

On the back of the cell is a spot of solder

cut a piece of ribbon wire so that it is about 2 inches.

tin the ends of the wire with solder

solder the ribbon to the back of the cell

Do this to two cells at a time for a total of four

 

Pair up the cells.

Hook the tabs of the front of one cell to the back of the other cell.

Solder the front tab of one cell to the back tab of the other cell.

 

Attach the cell pairs to the rotor block

Use double stick tape on the opposite sides of the block to hold the cells in place.

Do this to two cells at a time.

Once the cells have been secured in place, run a length of clear adhesive tape all the way around the block to hold them in place.

When one pair is complete, you can test it for conductivity.

You should have conductivity between the wrap wire and the cells.

If you test the other wrap wire, it should not have conductivity to the wrap wire you have just soldered to the cells.

 

Attach the wrap wires to the motor

make sure the ends of the wrap wire have been sanded clean with sandpaper.

You should be able to see the copper of the wire for about a half inch.

Wrap the copper wire around the soldered pair of tabs

Heat the connection and let the wrap wire into the solder

 

 

 

1-12-10

 

Solar installations

Each cell costs $1.50, you will need a total of four.

Cells are extremely fragile, be very careful and gentle with them.

 

We will need to do a few things to them to have them work on the motors.

 

Add Tabs

On the back of the cell is a spot of solder

cut a piece of ribbon wire so that it is about 2 inches.

tin the ends of the wire with solder

solder the ribbon to the back of the cell

Do this to two cells at a time for a total of four

 

Pair up the cells.

Hook the tabs of the front of one cell to the back of the other cell.

Solder the front tab of one cell to the back tab of the other cell.

 

Attach the cell pairs to the rotor block

Use double stick tape on the opposite sides of the block to hold the cells in place.

Do this to two cells at a time.

Once the cells have been secured in place, run a length of clear adhesive tape all the way around the block to hold them in place.

When one pair is complete, you can test it for conductivity.

You should have conductivity between the wrap wire and the cells.

If you test the other wrap wire, it should not have conductivity to the wrap wire you have just soldered to the cells.

 

Attach the wrap wires to the motor

make sure the ends of the wrap wire have been sanded clean with sandpaper.

You should be able to see the copper of the wire for about a half inch.

Wrap the copper wire around the soldered pair of tabs

Heat the connection and let the wrap wire into the solder

 

 

1-11-10

Solar cells are in!

The solar cells we will be using on the motors have arrived.

Each cell costs $1.50, you will need a total of four.

Cells are extremely fragile, be very careful and gentle with them.

 

We will need to do a few things to them to have them work on the motors.

 

Add Tabs

On the back of the cell is a spot of solder

cut a piece of ribbon wire so that it is about 2 inches.

tin the ends of the wire with solder

solder the ribbon to the back of the cell

Do this to two cells at a time for a total of four

 

Pair up the cells.

Hook the tabs of the front of one cell to the back of the other cell.

Solder the front tab of one cell to the back tab of the other cell.

 

Attach the cell pairs to the rotor block

Use double stick tape on the opposite sides of the block to hold the cells in place.

Do this to two cells at a time.

Once the cells have been secured in place, run a length of clear adhesive tape all the way around the block to hold them in place.

When one pair is complete, you can test it for conductivity.

You should have conductivity between the wrap wire and the cells.

If you test the other wrap wire, it should not have conductivity to the wrap wire you have just soldered to the cells.

 

Attach the wrap wires to the motor

make sure the ends of the wrap wire have been sanded clean with sandpaper.

You should be able to see the copper of the wire for about a half inch.

Wrap the copper wire around the soldered pair of tabs

Heat the connection and let the wrap wire into the solder

 

1-8-10

Mendocino Motor Concepts

http://blog.makezine.com/archive/2009/11/make_presents_the_inductor.html

Magnetism

Like the earth, magnets have a magnetic field.

The magnetic field of the earth is a background level of magnetism.

Magnets can come in a variety of strengths.

Ceramic magnets are less strong than rare earth magnets.

 

Electromagnetism

When electricity goes through a wire, it turns the wire into an electromagnet.

electromagnets have the same polarity as fixed magnets.

You can switch the polarity of an electromagnet by switching the polarity of the circuit.

You can turn the electromagnet on and off by adding a switch to the circuit.

More turns on the electromagnet will make it more powerful.

Having an iron material inside the electromagnet, an iron core, will make it more powerful.

 

Fitting the parts of the motor

Magnets want to either attract or repel each other.

If a magnet can move from its position, it will move away and cause a drag on the system.

The magnets in the motor need to be fitted straight and perpendicular to the part holding it.

 

How electric motors work

http://www.howstuffworks.com/motor.htm

 

how solar cells work

http://www.howstuffworks.com/solar-cell.htm

 

Test this idea:

Using the charge of a battery through the coil, can you get the coil's electromagnetic field to attract or repel a fixed magnet?

What is the effect of putting electricity through the coil?

Describe the electromagnetic field around the coil.

Push a small magnet on the table with your charged coil.

Can you get it to attract the magnet with the charged coil? 

 

1-6-10

Placement of magnets on the base

When you are placing the magnets on the base, you will want to keep a few things in mind:

The magnets should all face with the same polarity in.

The original instructions had South facing in.

The channels on the base are 1/2"

Each magnet is 1/4"

You will need four sets of two base magnets.

The magnets will need to fit snugly and upright in the grooves.

The grooves are close, but not exactly the width you will need.

You will fit the magnets by placing paper shims between the magnet and the base.

You will need to make sure the magnet stays straight and upright in the groove.

Properly set magnets should stay in place when pushed by hand.

 

Securing the magnets onto the rotor

On the rotor, you will be putting two magnets.

They will need to have the same polarity as the base magnets.

The front magnet, closest to the mirror, is centered on the front magnet of the pair closest to the mirror.

The back magnet is centered on the crease between the magnets in the back groove.

 

The front magnet holds it up and pushes it into the mirror

The back magnet holds it up.

 

The hole in the magnet is about the same size as a 3/8" dowel.

To fill in the gap, you will need some electrical tape.

First mark the location of where the center of the magnet will need to go.

Then cut a few inches of tape.

Place an end of the tape on the center of one of the marks.

Carefully and neatly roll the tape onto the dowel.

Slide the magnet onto the dowel and over the tape.

If it is too loose, peel back the tape and add an inch or so of tape a few layers under, then roll the tape back on.

Try the fit, add more, or take some off.

If it is too tight, you can try putting the magnet on with a twisting motion, and it may screw onto the tape.

If it is really too tight, you can shorten the tape by peeling it back and cutting it, then rolling it back onto the dowel. 

The magnet should stay in place without moving when you touch it.

 

 

 

Spin testing:

You can test the placement of the magnets.

all the magnets

 

1-5-10

Discussion about magnetic fields.

Electromagnetism is controlled by switching the electricity and by changing the voltage.

Electromagnetism is polarized. If you switch the direction of the current, you will switch the orientation of the magnetic field.

Review of the demonstration with the wires, nails and batteries of last class. Review also the homemade speakers made last class.

Testing the wrap wires

The wires coming from the rotor will be charged with a battery for testing, on the finished motor, they will be charged by the solar cells. This will create a magnetic field around the rotor, when the rotor is charged by the solar cells.

If the wrap wires are charged opposite of each other, their magnetic fields will actually stop the motor from running.

Carefully remove the ends of the wires from the tape and dowel.

Transfer the labels to the wires with tape.

Use sand paper to remove the insulation from the ends of the wire.

Confirm your labeling with the continuity tester on the multimeter.

Do this to all four leads.

 

To determine the polarity of the wrap wires, connect a battery to both ends of one of the wire.

Put the compass near the rotor and watch for deflection in the needle. Make note of where it is pointing.

If you switch the battery connection, you should see the compass also switch direction.

Identify which wire is connected to + when the wrap wire gives a North based magnetic field.

Repeat the process of determining polarity.

Make small tags for the wrap wire indicating 1N, 1S and 2N, 2S

Carefully and securely tape these tags to the wire so that they can be moved along the wire, but don't fall off.

 

Adding the magnets to the base.

you will need 8 magnets for the base.

Orient the magnets so that South is facing in to the center of the base.

Add paper shims to keep the magnets from slipping out of place.

The magnets should be straight up and down, and should not wobble or roll out of place.

Each pair of magnets should be about 1/3 from the outside edge of the base.

 

12-23-09

Installing the bearing point on the front of the rotor

Find the center of the end of the post

Drill a hole with a finish nail that is shallower than the nail you will use

Cut the head off of a finish nail.

Push the nail into the hole so that it stays, but not so hard that it splits the dowel.

 

Demonstration of working Mendocino Motors

MakeAnElectromagnet!

You'll need

some magnet wire

a nail

a battery

a compass

some staples, paperclips and other things with iron in them

 

Do It!

Wrap the magnet wire around the nail, keeping both ends of the wire out of the wrap.

Strip the insulation off of the end of the wire with sandpaper, a knife or a file. Nail polish remover can also work.

Connect the wire to the battery.

Pick up some small items with your new magnet.

Add a switch to it so you can turn it on and off.

Install your electromagnet on a crane and pick up some toy cars and other junk.

 

 

12-21-09

WrappingTheRotor

In wrapping the rotor, you will need:

Two 50 foot lenthgs of wire

A rotor block

a 3/8" dowel 8" long

a pencil

a scrap of paper

tape

 

The two lengths of wire will be wrapped in two coils on the rotor. You will need to solder to the ends of these wires after it is wrapped.

 

Assemble your supplies

Insert the dowel into the block so it is about halfway.

If the dowel slips around too much, you can put a bit of tape on the dowel at the location where the block will be. This will make the block fit more snugly.

Take your paddle of wire and loosen the end of one of the wires. Make sure the other wire is secured, cover the end with tape if needed.

Wind about three or four inches of wire on one end of the dowel. Tape the wire into place and tag this 1 S (first wire start)

Drop the paddle on the floor so that it can unwind.

Hold the dowel block in one hand, upright.

With one hand, guide the wire around the block in the groove.

Make sure that the wire goes into the groove all the way around.

Wrap 10 times on the left side of the dowel.

Write the number 10 on your scrap of paper.

Switch hands, being careful not to rotate the dowel.

Wrap 10 times on the right side of the dowel.

Write the number 20 on the scrap of paper

Switch hands, being careful not to rotate the dowel.

Repeat this process until you reach 100 turns around the block, which should be just about the end of the wire.

Wrap the excess wire around the other end of the dowel, tape it off and label it.

 

For the second wire, you will repeat this process, using the second pair of grooves.

 

 

12-17-09

MendoBuildSteps and process

 

 

 

 

12-16-09

Speaker Box documentation

Hand in prints of your pages at the start of this period for on time credit.

Need some help? Stay after and we'll work on it.

Mendo Motor parts and assembly

Make a RotorAssembly.skp file and add the dowel, rotorblock and two separate magnets

Assemble two magnets together in a file called TwoMagnets.skp

 

Make a MotorAssembly.skp document and

Add pictures of these to your blog as you create the parts.

 

12-14-09

Speaker Box documentation

Hand in prints of your pages at the start of this period for on time credit.

Need some help? Stay after and we'll work on it.

 

Mendo Motor parts

Use this link to get at the measurements of all the parts on the motor: Mendo Measurements

Assembly of the parts - MendoBaseAssembly

Once you have the parts of the motor, you will need to assemble the parts.

This page lists out how to make the first couple of parts and how to assemble them:  BaseAssembly

 

12-10-09

Speaker box documention

You should have two of the four pages done today

All four of the pages should be done by tomorrow.

Come after school today if you need help setting this up. 

 

Ning 

embedding a video from youtube

On the page of the video on youtube, there is a box with the embed code.

Copy the code and paste it into the top of your post for the video.

 

Mendo Sketchup

Assemble the base with grooves, upright and mirror

Design the mirror, ring magnets, dowel and block

 

Mendocino MotorMeasurements

We will make a number of the parts for the Motor this class.

Print your designs with dimensions

Email the files to yourself so you have a backup.

 

 

Add a post to your ning site with the parts you have designed.

Add a post to your site with the assemblies you make.

 

 

12-8-09

 

Speaker Box documentation

You should have two of the four pages done by next class.

Bring in prints of your pages at the start of class on Thursday.

Questions?

 

Mendocino MotorMeasurements

We will make a number of the parts for the Motor this class.

Print your designs with dimensions

Email the files to yourself so you have a backup.

 

12-7-09

SpeakerBoxDocumentation

MendocinoMotorOverview

 

12-3-09

This is the last class for working on the Speaker Box

Check in on where you are with the project.

If you are complete with the project, you can do a number of other things:

    Document your project with

        Text on your blog,

        Photos

        Video

Otherwise, you can work on other projects relating to sound, electricity, FM transmitters, design, etc.

These other projects will need to have some photos, or other documentation on your blog.

 

12-2-09

Hand in of packet of materials requested from last class.

Getting the project done

The last class we will work on this project will be the last class of this week.

If you are complete with the build, they can work on documenting the project on your Ning blog

Show what the project looks like

Photos and video

Explain what you have done on the project

Text and audio track in the video.

 

12-1-09

Are you up to date?

November09Checklist

 

11-25-09

Make an account on http://duxtech.ning.com/

Join the group for Principles Fall 09

Make a blog post with the response to the question of last class:

Assess your progress on the project so far.

Make a list of what you have done and what you have yet to do on your music player.

Look at the work that you have done on your project at this point.

Write out a description of what you have done on the project so far. 

Check with students who are more complete on the project than you and discuss the work you have yet to do.

Write out a description of what you need to do to complete the project.

 

In the class, work on your project. If yours is largely complete, assist your classmates to bring their work up to completion. You may want to bring the project home over Thanksgiving. If you do, bring it back to school the week after the holiday for more work on it and evaluation.

11-24-09

Make an account on http://duxtech.ning.com/

Join the group for Principles Fall 09

make a blog post with the response to the question of last class:

Assess your progress on the project so far.

Make a list of what you have done and what you have yet to do on your music player.

Look at the work that you have done on your project at this point.

Write out a description of what you have done on the project so far. 

Check with students who are more complete on the project than you and discuss the work you have yet to do.

Write out a description of what you need to do to complete the project.

 

In the class, work on your project. If yours is largely complete, assist your classmates to bring their work up to completion. You may want to bring the project home over Thanksgiving. If you do, bring it back to school the week after the holiday for more work on it and evaluation.

 

11-3-09

SpeakerBoxChecklist

 

10-27-09

This period, we are working on the decoration of the speaker box.

The requirements of the design are listed at this link Box decoration Checklist:

 

Email and printed reflection:

This period, answer these questions and email the responses to duxtech@gmail.com

Print out a copy as well and hand it in.

Reflection on the process of making their own custom designed stickers

 

10-20-09

weeding the sticker

Box sticker design requirements:

You will be designing stickers for your audio box with the vinyl cutter

You should restrict yourself to a maximum of One corporate logo, ideally, you should use none

Make designs for the top, sides, front and front and at least one on the inside

Measure the box and designs so that they will fit in the spaces

On your Open Office files, add your name to each file so that the print helps identify the person doing the work.

Print out the pictures actual size

Staple the prints together

Cut the images and weed them, then attach them to the box

 

Box decoration Checklist:

 

10-16-09

Today you should be working on designs for your speaker box.

Follow the instructions on this page:

TwoColorSticker

Sending a file to yourself

Check your measurements against the box or against the drawings you made previously.

 

The drawings handed in already are in the folder on the desk.

Make possible designs for:

  1. The right and left sides of your box
  2. The front panel of your box
  3. The inside of the cover of your box
  4. Print a copy of each of the designs that you make

 

 

10-13-09

How to design a multicolor sticker with Gimp and Open Office

TwoColorSticker

Sending a file to yourself

10-7-09

How to design a multicolor sticker with Gimp and Open Office

TwoColorSticker

Take this brief survey; http://bit.ly/2sDt61

 

10-6-09

Take this brief survey; http://bit.ly/2sDt61

 

 

9-28-09

Junkbot Videos Link

 

9-25-09

Junkbot Video Homework Assignment Link

 

9-11-09

What do the parts of the CD drive system do and how can I find out?

Exploring a CD drive

 

9-8-09

How can we get project supplies from the useful but discarded objects around us? What are the techniques used to solve the manufacturing problems in modern devices?

 

Online version: 

http://blog.makezine.com/archive/2009/08/how-to_cd_drive_scavenging_for_part.html

Mastery Objective:

Students and participants will know how to safely disassemble a CD drive or similar electrojunk for parts and project supplies so that they can name the parts inside the device, compare the varieties of manufacturing techniques to solve the same problem and organize the usable parts and components for future use in projects.

Process:

What do you have?

Probably the first thing to do is look at the exterior of the drives you have.

Make note of any markings on the drive. Some things you will likely find are the manufacturer, model number, read/write speed of the drive and my favorite: Date of Manufacture.

The date of manufacture will give you some context to judge the drives in your collection by. Often the older the drive is, the more "off the shelf" the components are.

Use your camera:

Take some photos with your camera or camera phone to show the process of taking the drive apart.

You can also have participants and students take pictures of each of the systems they find, and each of the types of components they find inside.

Case disassembly:

Put on your safety glasses.

Use a screwdriver to take the metal case off the drive. It will usually be 4 phillips screws on the sides that hold it together.

In taking off the metal case, try to keep it from getting deformed. The steel can be useful later. You may find that there are plastic tabs holding one of the pieces in place.

Try to get the case to just fall apart without having to be forced. Most of the time it will just come apart after you remove the screws and press on the plastic tabs.

If you do have to tug on the parts, you may have missed a screw under a sticker. If all else fails, make sure all of the eyes are protected, and pull it apart carefully, probably below the table.

Pop open the CD drawer by straightening out a paper clip and slipping it into the hole on the front panel. The drawer should open easily. You might even find a disc inside.

To remove the drawer, you may have to pry apart the plastic sides, or it might just come apart easily. Different models have varying designs. Be careful if you put force on it that the parts don't fly and hurt somebody.

Be careful not to Over-Disassemble!

You may find that there is a dc motor that is in a plastic housing that holds it in contact with a gear which could serve as a nice little drive wheel. Take it out, but secure it together so it can be used in a future project. If it doesn't stay together with screws or pressure fitting plastic, run a bit of tape around it to hold it.

You may also find that the CD reading eye moves nicely on its' slides. If it is controlled by a DC motor, this could be a neat system to use later.

Basically, look at the things you are taking apart, and see if they can be used as systems or components.

Securing the wires coming from the motor with a bit of tape will help keep them from breaking off later.

Motors and how to read them:

You should find two types of motors inside: DC motor and Stepper motor.

The easiest way to identify a DC motor is by looking at the number of wires coming off it. Most have just two wires. DC motors are controlled by sending electricity through the motor, causing it to turn either clockwise or counterclockwise. Sometimes you may find that there are several more wires going into another area of the case. These can be to an encoder that helps read the speed and direction of the motor.

Stepper motors have more wires coming from them, and often are built right onto a circuit board. These turn by receiving a series of pulses, each of which advances the motor one step. By controlling the timing and quantity of the pulses with a microcontroller, it is possible to precisely set the speed and even the number of degrees the motor will turn.

Save the good bits

As you go, put the useful parts into plastic bags or bins. Label the bags with scraps of paper for easy identification.

You should be able to find at least the following:

Desolder the components you want from the circuit boards:

The headphone jack, LED, momentary switches and sometimes motors will be soldered directly to the circuit boards. You can use a desoldering braid and an iron to free these items from the boards. If they have fittings, you may want to keep the fittings and instead remove the headers that connect them to the board. You should be able to scrape the coating off the metal traces to solder the fittings to a wire for future projects.

 

9-3-09

Welcome back!

Introduction to course

Handouts:

Course expectations

Safety rules

Course Overview