Using Lego Mindstorms to bring a cake to life
I was recently asked to bring a cake shaped like a tank to life for my newphew. Luckily I had an old version of the Lego NXT which I wasn’t using. The Lego NXT system is pretty awesome, it comes with a basic set of servos and sensors and you can then use a very simple drag and drop interface to program it.
I initially worked by programming the Lego, below is the program which I used complete with sound effects. It uses a very simple of program, there is one motor which spins a bit to the left, a bit to the right and then plays a sound. The program looks like the following:
This simple behviour looks like this:
The cake board
We need to construct a special cake board so we were able to switch the cake on and off. This envolved cutting a hole out of a piece of MDF so we could see the screen and activate the buttons.
Building the cake
The cake is made from a simple sponge which is in 3 layers. Each layer has a hole in the middle to fit the Lego, which was encased in a box. The turrent is constructed out of rice crispys and marshmallows with the Lego cast into them. Then it’s a simple case of mouting the turret on the top and decorate.
Unfortuantely under the 3 layers of cake you can no longer hear the tank sound.