Concept
The user follows simple instructions on the cards provided (haven't thought about where these might be kept yet, maybe in letterboxes?) and draws the picture from the card. The user can also experimant by mixing and matching cards or by making their own drawing and code instructions.

Physical interface
The exhibit will look like a drinking trough with an old style pump tap and an old car tyre sitting on top, next to a row of letterxoxes containing code cards.

Mechanics:
In order to draw anything the paper and tyre must be able to move sideways, the tyre must be able to rotate and the pencil go up and down (on and off the paper). The tyre and paper must both able to move to get a diagonal line on the paper and a circle not centred in the middle of the paper.
In this pic the red line represents the lines that can be drawn by the movement of the paper. The green lines are the paper movement, the blue lines are the tyre along the trough and the rotation of the tyre will allow us to draw circles at any of these points but I have not shown that here.

This pic shows the same thing if the tyre is rotated 45deg:

You can see the only wat to get an accurate diagonal line (blue) is by moving the tyre along the trough because the axis of the paper movement on top of the tyre moves with the tyre when it rotates, but the axis of the trough does not.

Design look
Paper movement mechanism.


 

Interaction
The user will choose a set of cards from a particular letter box, the cards will be the same colour as the letterbox and will be in a numbered sequence. The cards in each letter box contain the instructions to construct the image of the name on the letterbox eg CAT, DOG, ANT, SHEEP etc
(Obviously a better cat than this!!!)

The instruction cards will consist of different combinations of the letters cgat, the user sets the machine to the correct position by finding the code on the trough that corresponds to the code on the card and turning or moving the tyre so that the appropriate pointer is pointing at the code sequence. All these movements of the tyre produce lines on the paper that eventually make up the picture on the card. eg

If searching for the combinations of cgat is too confusing or difficult the instructions could be simplified to involve numbers, letters and directions eg rotate the tyre to number 7, move the tap to closed, move the tyre to the letter c etc.

There will be a number of features on that are the same on each image so that it would be possible to swap certian cards between groups and add features successfully, eg adding cats whiskers to an ant. If any other combinations are tried eg put a cats tail on an ant, we know this is impossible and the result would be a failure.

As part of the visitor activity sheet students may be encouraged to make their own drawings from their own codes.

Information provided by exhibit
This exhibit reinforces the fact that dna is a code and as such can be used to describe anything. If the user imagines trying to describe an entire person using code they begin to grasp how huge and complex that task would be. It also shows how although it is difficult, it is possible to mix and match instructions to get different results.

Graphic panels

index