Outline

Intro to Physical computers and wearables!

What is Physical Computing? Is it around us? Do we see it?  How does it help us?

Integration of Fashion and technology through Physical Computing - 

Some cool, some functional and some extreme examples [Steve Mann!] / Maggie Orth

How things work_ the basic concepts:

*What are “wearables”?           

*What is an Interface?  some basic and fancy examples using physical computer and  not!

*Digital vs./ and /or Analog [what is what!]       

            *Electricity

                        _What’s electricity?

                        _How does electricity flow? Setting the scene for it                  

                        _Current , voltage , resistance  [their relationships] V= I x R

                        _Whatis a circuit?

                        _what is a conductor? Copper, etc.

                        _what is a insulator? Plastic, wood, etc. // keep in mind he purpose!

                        _what is a resistor?

                        _what is a capacitor? Special types : LED’s

            *Computers

                        _What is a computer and what are its components? [hardware, software,

                        firmware].  Some examples [I will bring pre-programmed pic chips to

                        show them]

                        _Differencing circuits from computers

*The basic elements 

_What is a microcontroller?

_What is a breadboard?

_What is a switch? [ one of the most important elements] examples!

(photoresistors / flex sensors

Discussing-

Lets incorporate a switch into nurse’s uniform.

Case scenario:  A doctor’s clinic.  What is the interaction between the doctor and the patient like? What are the different variations of this situation? What are the different kind of doctors?

What happens when there is a call? What about when the patient is interacting with the patient and the doctor need to be interrupted or needs additional help from  nurse?

What  about the nurses uniform’s?  how has it evolve through history? (scrubs). Male vs. Female.  The color.  What do the symbols mean or lack of. What is a nurse like? What is her /his interaction with the doctor like?

Building- a communication device for the nurse’s uniform. 

The device: a bracelet or a removable pocket that will work as a switch.  When making contact to a switch embedded into the wall it will active LED’s that the doctor will see. The doctor will respond by activating a switch (3 options will be given).   Switch 1(green = come in ) , or switch 2 (yellow = wait around for a little ), or switch  3 (red = do not bother !) . [based upon the idea  of the “do not disturb”  signs.   The device used by the doctor will used a pre-program chip.  The kids will be able to wire a circuit and light and  LED .  Then we will all together assemble the a communication device for the nurse’s uniform.  

Testing -  the device and the interaction with it .  (Documentation)

Goal: For the kids to analyze a social situation understand it and practice their newly acquired physical computing skills.   A design exercise that helps them incorporates the new concepts (electronics) in a design.  Also expose them to the use of a microchip chip.

AV cables

For use with today's more sophisticated video equipment that allows component input from high-end gear like the PlayStation 2 computer entertainment system, the Component AV Cable delivers impeccable, distortion-free picture quality. This cable works with TVs and monitors that have Y, Cb/Pb, Cr/Pr inputs. If your entertainment center is ready, prepare for the leap in detail you'll see with the Component AV Cable (for PlayStation 2).

Concepts!

Digital Vs. Analog  ( what is what !)

How do we make a computer work!?!

Differnecing circuits from computers !

An idea 

Undertanding : Software , hardware and firmware 

What  is physical computer?

What is a micrcontroller ?

What is a breadboard?  http://tigoe.net/pcomp/breadboarding.shtml#

Whatis a switch?

What is electricity?

Current , voltage , resistance, a circuits

http://tigoe.net/pcomp/basic-elec.shtml

The components :

Conductors are materials through which electrical current moves freely.

Insulators are materials which prevent the flow of electricity.

Resistors resist, but do not totally block, the flow of electricity. They are used to control the flow of current. Current can move either way through a resistor, so it doesn't matter which way they're connected in a circuit.

Capacitors store up electricity while current is flowing into them, then release the energy when the incoming current is removed. Sometimes they are polarized, meaning current can only flow through them in a specific direction, and sometimes they are not. If a capacitor is polarized, it will be marked as such on the diagram. Don't wire a polarized capacitor backwards; it might explode.

Diodes permit the flow of electricity in one direction, and block it in the other direction. Because of this, they can only be placed in a circuit in one direction.

Light-Emitting Diodes (LED's) are special types of diodes which emit light when current flows through them.

There are many other types of components which you'll come across:

•   switches control the flow of current through a junction in a circuit:

         •        transistors and relays are switching devices:

         •        thermistors change resistance in reaction to varying temperature;

•    photoresistors change resistance in reaction to varying light;

•    flex sensors change resistance in reaction to being bent or flexed;

•    piezoelectric devices create a varying voltage in reaction to slight changes in pressure.

Relationships

Voltage (V), Current (I), and Resistance are related (R) are all related, by the following formula:

 Volts = Amps x Ohms, or V = I x R

Current (I), voltage (V), and resistance (R) are also related to electrical power (P) (measured in watts), as follows: Watts = Volts x Amps or

W = V x A

Electrical current flows from places of higher potential energy to places of lower potential energy (i.e. from positive to negative).

Ground is the place in a circuit with where the potential energy of the electrons is zero. Sometimes this point is connected to the actual ground, either through a grounded electrical circuit, water pipe, or some other method. Basically, any conductor that goes to the earth will do.

A few important rules:

Current follows the path of least resistance to the ground. So if it has a choice of two paths in a circuit, and one has less resistance, that's the path it'll take.

In any given circuit, the total voltage around the path of the circuit is zero. Each component that offers a resistance lowers the voltage, and by the time we reach the end of the circuit loop, there will be no voltage left.

The amount of current going into any point in a circuit is the same as the amount coming out of that point.

These last two rules give us a way to figure out what's going on when we put components in a circuit. When we look at how components in a circuit are placed in relation to each other, there are two ways we can do it: one in line after another, or side by side. When they are one in line after another, we say the components are in series with one another. Side by side, they are in parallel with one another.

Let's look at how the current and voltage changes when components are in series or in parallel:

When two components are in series, they are placed one after another, like so:

When resistors are in series, the voltage drops across each resistor, and the total resistance is equal to the sum of all the resistors. We know in the above circuit, the current anywhere is constant. We know the voltage drops across each resistor, and we know that the total of all the voltage drops equals the voltage across the battery. So Vin = V1 + V2. If we know the values of the resistors, we can use the formula V= I x R to calculate the exact voltages at each point.

For resistors in parallel, the voltage across them is equal, but the current is divided between them. The total current is constant, however, so we know that the divided current across the parallel resistors is equal to the total current. So I1 + I2 = Itotal.

Though it's sometimes useful to think about the mathematical relationships of parallel and series circuits, it's often more useful to think about them in terms of practical effects. Again, think of the water metaphor. For the series example, if one resistor lowers the voltage (water pressure), only a smaller voltage (trickle of water) gets through to the next. For the parallel example, the amount of water from the main stream (total current) gets divided into two streams, but the total amount of water flowing through those two streams is equal to the original amount of water. Keeping in mind these basic relationships will help you figure out what the effect of one component is on another when you see them in a circuit together, even if you don't know (or care about) their precise mathematical relationship.

When you're ready to begin building circuits, read the notes on breadboards for a quick introduction to how to use a solderless breadboard.

* For more notes on physical computing i visit Tom Igoe's site most of these notes have been obatined from his Physical Computer site.