1.7 Piggy Bank¶
In this project we will use Speed sensor module, Raspberry Pi and Scratch to make a Piggy Bank.
Place a piece of paper in the middle of the Speed sensor module and you will see a coin fall into the Piggy Bank on the stage.
In this project, we need the following components.
It’s definitely convenient to buy a whole kit, here’s the link:
ITEMS IN THIS KIT
You can also buy them separately from the links below.
Build the Circuit¶
Load the Code and See What Happens¶
Load the code file (
1.7_piggy_bank.sb3) to Scratch 3.
The 2 terminals in the middle of the speed sensor, one is to send light, one is to receive light; if you put a piece of paper in the middle to isolate the light transmission, thus the speed sensor will output a high level. At this point Scratch receives the high level, then switch the costumes of the sprite and you will see a coin fall into the Piggy Bank on the stage.
Tips on Sprite¶
Select Sprite1 and click Costumes in the top left corner; upload piggybank1.png, piggybank2.png and piggybank3.png from the
~/raphael-kit/scratch/picture path via the Upload Costume button; delete the default 2 costumes, and rename the sprite to piggybank.
Tips on Codes¶
When pin17 is low (no coins are put in), switch the sprite’s costume to piggybank1.
When pin17 is high (a coin is put in), switch the sprite’s costume to piggybank2, and after 0.5s switch to piggybank3, so that we can see a coin falling into the Piggy Bank on the stage.