All done for the term

I took some video of individual monsters today. The disk i handed in with my portfolio has more videos- which are of higher quality than Blogger supports. Here's a few of them for ease of access.

The Inline Eight rotation to reciprocation convertor:


The round peg in the square hole:


The Floor Scraper

End of term display

Here are some images from my project's final display:

Aftermath

Here's a quick video I took with my digital camera. Better quality video to be included in portfolio.

Another one down

I lost another AC motor today. Of three AC motors I've used, two have already failed. I'm going to have to focus more on my DC motors and fans if I'm to have any acceptable level of reliability. Due to their low power this will require additional focus on gear ratios and other forms of mechanical advantage.

Newest addition to the family

This one moves laterally along the horizontal wire. Momentary touch switches are gong to be added to either side in order to change direction once the end is reached. I may leave taking care of direction switching to other monsters instead. This is something that will be finalized on final monster grouping composition.

Visualizing

I've been working abstractly in 3D rendering to play with ideas of shadow interaction and the spatial flattening that occurs in the transition from 3D volume to 2D plane. This will allow me to work more efficiently tomorrow once I start hanging machines. Here's a couple images of one of the situations I've been exploring.

Setting up

The jury room is finally being cleared out of the last of the concrete projects. I have reserved myself a spot and will begin setting up tomorrow. It will be nice to have space to work in for a change.

Drawings

Here's the images for my two built items.
The rotating sound controller:



















And the Scraper










Both images come from analyzing video of the item in question and pulling out the core movement involved.

Shadows and (in) Motion

Here's a B&W collage image of the shadow projection of my rotating machine. This image is the result of combining the shadows produced while in operation. The band where the light sensors get placed is clearly shown as it is the only area with any effective amount of shadowing.

Responding

In response to the questions presented to us on Friday by Patrick.
What does my machine do?
Simply put it vocalizes visual inputs.
What is it about?
The rhythm of movement.
What is its purpose?
Synaesthetia.
What is its site?
Pretty much anywhere people move.

So far, so good

I've managed to get the "movement" portion of my project functionally complete, now all I need is to rig up my screen and get the light controlled circuits nailed down.
Here's a couple videos showing the items in question.

Schematic

Here's a quick plan view schematic of the kind of thing I'm working towards.

Movement

After a little careful redirection, movement of my components has now become a part of my project as well as audio and shadow projections. I've been playing a little with movements and changing relationships between the electric motors and the guitar pickups that are generating noise from the produced electromagnetic fields. Here is a quick video of one of them.

Light Controlled Noise in action

Here's a video of the circuit in action. Unfortunately there was sandblasting going on outside our window so the audio isn't what I would like it to be. The operation can be heard though.

Light Controlled Noise Circuit

Here's a pic of the circuit I described a few posts ago.

Filling in the blanks

Here are a few images of a couple of my de-monsters that I neglected to post here earlier.

Recording the presence of movement in a space in a paper loop:

Not yet shown is the motion sensor/ AC motor contraption that made the above circuit reactive. Will edit for its addition soon.

Creating reciprocating movement by changing the voltage applied to a fan:

Light Controlled Noise

My work this past few days has entailed trying to refine the way my pick-ups react to movement. My initial attempts with the motion sensor and the ignition coil provide an auditory cue whenever someone was present, but it was a bit of a Rube Goldberg machine. It required more steps than was necessary to complete the task. Another major failing was that the nature of the noise was exactly the same regardless of the size and speed of what caused the movement.
Addressing these issues I have designed a new setup. It involves an array of photo-transistors attached to an array of Darlington transistors. The photo-transistors are used to trigger the Darlington transistors when they are exposed to light. The Darlington transistors then provide a ground for a DC electric motor- turning it on. The way I am able to differentiate one photo-transistor's input from another is by where in the circuit a ground is applied. The motor is attached to a circuit which is normally open and has a number of resistors (the same amount as the number of photo-transistors minus one) hooked up in series on the ground side of the DC motor. The grounds from each photo/Darlington transistor pairing are applied in different places between these resistors along the circuit. This causes a different amount of resistance to be present between the DC motor and ground depending on which pairing has light, and as such, a different speed is achieved by the motor. This speed difference isn't very obvious visually, but the sound difference from the motor is- especially when the electromagnetic field is picked up by the guitar pickups and amplified.
This development achieved much of what I set out to accomplish, but was still not exactly what i was looking for. The lacking, I felt, was in the way this can be used to respond to movement- especially that of people. When we move around, we don't create light wherever we go- But, we DO create shadows. This caused me to redesign my previous circuit so that when light is received by the photo-transistors power is transferred through to the ground side circuit of the DC motor. This stops the motor when light is present due to the equivalence in voltage on either side of the motor. Once a person moves through the space, they block the light to one or more sensors, causing the transistor pairing to close, and remove the power from the ground side of the DC motor- which in turn allows it to operate. This method requires special attention to dropping of voltages over resistors and the prevention of shorted circuits. The benefits are worth it though as less components are required compared to other solutions. For example, an array of relays could be used to do the same task with a little less hassle, but more cost and unnecessary complexity.

Information sources

In an effort to locate the sources for a lot of the knowledge I've been relying on so far in my experimenting I had to go back to my old text books. Here are a couple of pages from "Physics For Career Advancement" 5th edition by Ewen, Nelson, and Schurter:

The pick-ups are, well, picking up

With the understanding that the guitar pick-ups are activated by changes in their magnetic field and the creation of a magnetic field around a flowing electrical current it is not surprising that the guitar pickups create noise (when paired with an amp of course) when adjacent to any operating electrical component. This includes wiring. The catch is that having voltage present alone isn't enough, there needs to be a complete circuit that is operating in order to create a response.

Electric Guitar wiring diagram and specs

Here's some guitar specific info:

Electromagnetic Induction Research

Here's a quick look at what I've been finding- This version is lifted directly from the website:

http://www.rare-earth-magnets.com/magnet_university/history_of_magnetism.htm

1820 - Electromagnetism, Current

In 1820, a physicist Hans Christian Oersted, learned that a current flowing through a wire would move a compass needle placed beside it. This showed that an electric current produced a magnetic field.

Andre Marie Ampere, a French mathematician who devoted himself to the study of electricity and magnetism, was the first to explain the electro-dynamic theory. He showed that two parallel wires, carrying current, attracted each other if the currents flowed in the same direction and opposed each other if the currents flowed in opposite directions. He formulated in mathematical terms, the laws that govern the interaction of currents with magnetic fields in a circuit and as a result of this the unit of electric current, the amp, was derived from his name. An electric charge in motion is called electric current. The strength of a current is the amount of charge passing a given point per second, or I = Q/t, where Q coulombs of charge passing in t seconds. The unit for measuring current is the ampere or amp, where 1 amp = 1 coulomb/sec. Because it is the source of magnetism as well, current is the link between electricity and magnetism.

1830 - Inductance

In 1830, Joseph Henry (1797-1878), discovered that a change in magnetism can make currents flow, but he failed to publish this. In 1832 he described self-inductance - the basic property of inductor. In recognition of his work, inductance is measured in henries. The stage was then set for the encompassing electromagnetic theory of James Clerk Maxwell. The variation of actual currents is enormous. A modern electrometer can detect currents as low as 1/100,000,000,000,000,000 amp, which is a mere 63 electrons per second. The current in a nerve impulse is approximately 1/100,000 amp; a 100-watt light bulb carries 1 amp; a lightning bolt peaks at about 20,000 amps; and a 1,200-megawatt nuclear power plant can deliver 10,000,000 amps at 115 V.

1855 - Electromagnetic Induction

Michael Faraday (1791-1867) an Englishman, made one of the most significant discoveries in the history of electricity: Electromagnetic induction. His pioneering work dealt with how electric currents work. Many inventions would come from his experiments, but they would come fifty to one hundred years later. Failures never discouraged Faraday. He would say; "the failures are just as important as the successes." He felt failures also teach. The farad, the unit of capacitance is named in the honor of Michael Faraday.

Faraday was greatly interested in the invention of the electromagnet, but his brilliant mind took earlier experiments still further. If electricity could produce magnetism, why couldn't magnetism produce electricity. In 1831, Faraday found the solution. Electricity could be produced through magnetism by motion. He discovered that when a magnet was moved inside a coil of copper wire, a tiny electric current flows through the wire. H.C. Oersted, in 1820, demonstrated that electric currents produce a magnetic field. Faraday noted this and in 1821, he experimented on the theory that, if electric currents in a wire can produce magnetic fields, then magnetic fields should produce electricity. By 1831, he was able to prove this and through his experiment, was able to explain, that these magnetic fields were lines of force. These lines of force would cause a current to flow in a coil of wire, when the coil is rotated between the poles of a magnet. This action then shows that the coils of wire being cut by lines of magnetic force, in some strange way, produces electricity. These experiments, convincingly demonstrated the discovery of electromagnetic induction in the production of electric current, by a change in magnetic intensity.

1880-

James Maxwell (1831-1879) a Scottish mathematician translated Faraday's theories into mathematical expressions. Maxwell was one of the finest mathematicians in history. A maxwell is the electromagnetic unit of magnetic flux, named in his honor. Today he is widely regarded as secondary only to Isaac Newton and Albert Einstein in the world of science.

Maybe not so gentle after all

Sorry Mr. Roboto

Moving on

I've decided to look at the guitar as two complementary, yet separate, systems.
There is the string mounting system that holds the strings in tension with adjustments to allow for tension and height (above pickups/frets) to be easily changed.
The second system is the electrical system involving the pickups, corresponding switches and "Tone" controls as well as the "Volume" control and cable connection.
There is no physical connection between the two systems yet they work in unison to provide the functionality of a guitar.
My interest in this item, moving forward, is to disregard the strings and see how else I can use the pick-ups to make noise through an amp.

For now though, I believe I am supposed to be disassembling a different item. C'mon over little robot friend, I'll be gentle.

Vivisection Images

Here's a couple picturesfrom my vivisection this weekend.

Inducing Voltage

The underlying principles of an electric guitar are simple. Voltage is induced through the alteration of a magnetic field within which is found a coil of wire. All of this occurs within the pick-ups and is caused by the moving (vibrating, etc.) strings.

The most beneficial aspect of this operation for my purposes is that it requires no electrical power to work. The signal is generated through the conversion of physical movement to an AC Voltage.

Basic voltage induction theory will tell you that anytime a conductor gets exposed to a moving magnetic field a voltage will be induced.
The common ways to create a moving magnetic field are:
-Moving a magnet (shocking, i know)
-Expanding or collapsing a magnetic field (electromagnets need only apply for this one)
-or (as an electric guitar does through the use of metal strings) The movement of another conductor within the field.

The voltage created is a very weak Alternating Current. It is made stronger in this application by using a coil of wire so that the magnetic field has more wire in which to induce voltage. The amplifier that guitars are plugged into are required to -as one would guess- amplify the still rather weak current provided by the guitar and use it to drive speakers.

Creating Autonomous Mechanical Creatures

Here's something I found:


I found it here: http://www.ted.com/index.php/talks/view/id/162

The difficulty in drawing an Icon

My art skills have never been especially strong, but they've always got me by. The task I find before me is proving to be far more difficult than I had expected. Drawing a Fender Stratocaster should be easy- but- EVERYONE knows what it is supposed to look like. It has an Iconic form and presence in North America (and elsewhere I imagine). Its shape is known to even the least musical, and any mistakes I make in representing this shape on paper will be immediately evident to anyone. Oh well.

Items Finalized

The record player has finally been obtained and I managed to talk my brother out of his old electric guitar. I've always wondered exactly how both of these items work- now I'll have an excuse to find out

Updated Items list

I recovered from surgery nicely- although I am stuck wearing a white plastic splint till Monday. I think the worst part was likely the anesthetic hangover.
So back to business it is. The record player has become an issue, but I still hope to have one by the end of the day. Also added to the list is a motion sensor light.

First Vivisection of the year

I was involved in my first vivisection of the year earlier today. Unfortunately I was the vivisectee. I had septorhinoplasty this morning to straighten out my nose and its inner workings so I can breathe.

First Items acquired!!

So far I've managed to get my hands on:
- A remote control robot
- A child's music/learning station
- An old record player (my favorite so far)