ETL216 Assessment 1By XXXX

Sem 2, 2011

Design, Make, Appraise

EARLY INVESTIGATIONSGoogle image search: “electromagnet” (below)http://en.wikipedia.org/wiki/Electromagnethttp://science.howstuffworks.com/electromagnet.htm

EARLY INSPIRATIONS

Source: Brian Lewthwaite*

LEFT Sketches by authorHow to adapt crane into scrap metal lifter

Source: http://www.atlanticpixel.com/3d-prototyping-rendering.html#

RIGHT Source:Baker, W & Haslam, A, 1992, “Make it Work! Electricity”

MATERIALS - RECYCLEDMy electronics work bench (left).

My initial collection of

recycled and reclaimed

household items (right, and

below).

MATERIALS - SALVAGEDAn opportunistic discovery! Dissection of a dumped TV set (top left) and set top box(bottom left).

This find resulted in a generous source

of insulated copper wire for the

construction project (right)…

…and revealed complex industrial

electromagnets, though I was

unable to make them useful (right).

METHODS & TOOLS - WIRES

Wire strippers were not available. I experimented with a variety of techniques to remove insulation (left) and to manipulate wires and other components (below).

MATERIALS – RODS & COILSA kit component was convenient to hold the batteries and wires while I experimented with suitable materials to became familiar with circuits and electromagnetic principles. I used a variety of different sized rods, disks, wires (including a spring), and varied the number of coils of wire to see the effects.

PROBLEM SOLVING - TERMINALSIt was soon apparent that wires could not simply be wrapped around battery terminals to keep them in place. My research showed that alligator clips would be effective for most terminals, but I didn’t have any. My improvised clips achieved a connection in some cases, but only some of my clips fit some of the terminals some of the time.

I had attempted to tape the wire to the terminals, and to use rubber bands to hold wires, but neither of these solutions were very secure once the circuit was handled.Eventually I snipped ends off a spring, which gave an adequate fit to one terminal of the square battery. The spring from the hobby kit fit onto the other (right).

CONSTRUCTION - PROTOTYPEThe easiest way for me to move forward with the loose idea in my head was to actually place a battery and a nail in position, and to review my design from the simplest point possible.I initially used scrap cardboard as no special tools were required (left). The square battery was used as the negative terminal was easier to connect a wire to than any other terminals I’d experienced.

Through this initial prototype I learnt that coiling wire around a nail could only occur after the nail was fixed in place, especially if mounted in wood.I had trouble connecting the second wire to the terminal. At this point I decided to create a switch…

PROBLEM SOLVING - SWITCHESInitially I just needed the loose wire to be more stable so I could touch it to the positive terminal with more control (right). This switch was still unstable and clumsy, so after researching more about switches, I experimented with a number of suggested switch types, using different materials and mediums (below).

Swinging paperclip

Pin release Foil pressure

PROTOTYPE - SWITCH

The paperclip switch appeared to be simple and effective, but the sharp points of the tacks created a new problem (top right). With repeated use, the switch became less effective, which frustrated the experience.The tacks had became too loose in the card and I feared this would also occur if they were pressed into wood, due to the wires being run beneath them. I experimented further with reclaimed objects that could conduct the current and potentially be screwed into wood. The large curtain hook (right) was my preferred choice due to its length, flexibility, and potential ability to be screwed.

TESTING - PROTOTYPESThe cardboard prototype was operable, but was not suited to portable use due to the unstable connections between the wires and the battery terminals.Concentrating on connections caused too much distraction for users, and was especially frustrating for a younger child (aged 7), who was happier playing with regular magnets provided instead.

METHODS & TOOLS - WOODWORK

I needed instruction to use a variety of tools and methods to complete the artefact, where the essential components could be mounted securely onto a piece of scrap timber for extra durability. The holes in the curtain hook needed to be adjusted with pliers in order for screws to fit.

CONSTRUCTION - ADJUSTMENTS

Finally the wire could be coiled around the nail. Different coloured wires are used for different sections of the circuit, to help illustrate how each component contributes to the circuit. There is a join between two coloured wires to facilitate replacement of one or the other in future (above). Battery position is adjustable and held in place by thick rubber bands, allowing batteries of different sizes to be frequently interchanged. Cardboard frames (right) are used to stabilise curved batteries in correct position to wires. A cork was later added to protect the nail spike.

PACKAGINGThe original choices for reclaimed packaging (left), and the final selection (right) based on size, strength, and exciting vibrant colour.

FINAL PRODUCT

TESTING – FINALThe final artefact was demonstrated briefly and without explanation to a small group of children in years 3, 5, and 6. Those who had not seen the prototype before at first considered it a “magic trick”. All were keen to have a turn, and did not need instruction in its use. It withstood repeated handling and led to questioning and extension activities.

EXTENSION ACTIVITIESThese user-led extensions of the activity allowed for even the youngest member of the family (age 3) to explore and experiment with magnetic forces.

There is also a YouTube video available showing some footage of testing in place:

EXTENSION ACTIVITIESOlder children co-operated well (below) to use the electromagnet to classify which objects were attracted by the magnet (right, top) and which were not (right, bottom).

ACKNOWLEDGEMENTSThanks to my family for your support and ideas, and patience while the dining table was out of use.

Thanks to the entire family of XXX and XXX, for being my guinea pigs, giving feedback, encouragement, and continued interest and questions!

Thanks to the sales staff at Jaycar for trying to answer my questions while my knowledge was developing, and for providing some useful tips for sourcing recycled materials.

Thanks to the fellow CDU students who provided support via Learnline, and to lecturer Greg Shaw for continually trying to give hints away on Wimba.