Hildegaard, The Witch

by Tegan Cohan, Diana Fong, and Tiina Vuorenmaa

Our Intentions

Our first plan had been to make a witch, or cook, that would consist mostly of two arms: one to get ingredients and put them into a cauldron, the other to stir the ingredients in the cauldron. Music would be added later for special effects. Also the user has the choice of picking which ingredients go into the cauldron. A sort-of menu bar would be presented, in which 3 to 4 ingredient buttons can be pressed, and then an "enter" button to tell the witch that the user has decided. (Because of time constraints, we didn't make the stirring arm.. )

The Parts

The Rail - This is the part of our witch's "arm" that allows it to move sideways. There are two long gear-tracks on which the rest of the "arm" travles on. It moves slowly, partly because of the swirly-gig gears called worm gears.

The Arm Extender -This part gives forward and backward movement to our arm, allowing it to reach out and get the ingredients needed. Two 24-tooth gears on each side of the Wrist push two tracks that are on the sides of the Wrist.

The Wrist - This is the part that acts like a wrist. It allows the witch to pour the ingredients into the cauldron. We got to take advantage of a really nifty piece of lego that allows us to make it turn like a wrist.

The Hand - We had a choice here to either use electro-magnets to hold and release the cans of ingredients or to use a motor to lift the wrist and therefore, the can off of the counter. The electromagnets we had were kinda heavy, so.. We went with the latter idea. What a mess!

The Program

The program of our witch has two parts. The first is for the witch to wait for the user's input. After choices have been pressed, and the "enter" key pressed, the program would enter the second stage. At this second stage, we would have simple subprocedures made to reach each ingredient. Four global variables are used to represent the four choices of ingredients. The subprocedures are altered for each ingredient. A "deciding" subprocedure would decide if we need to go for the ingredient or not. Once it is through going for the ingredients, the program resets itself and begins at part one again.

Here you can see our formal code in hblogo.

The Finished Product

Here's Hildy! (these pics come to us from Mary Coyne- Thanks!)...