The brief: Blairdrummond Safari Park asked us to design something that would feed and enrich the lives of their tigers, giraffes, macaques, chimpanzees or elephants.


After generating a range of concepts for all the animals my group focussed on developing Downfall, a puzzle game for the chimps that upon completion rewards the chimp with a treat.

At the beginning of the day a number of tokens are loaded at the top of the device. The chimps can then pass a token from the top of the puzzle to the bottom, from disk to disk. Once the token passes through the bottom it hits a microswitch sending a signal to a micro controller which then triggers a bipolar stepper motor to turn half a revolution. A disk inside a tube filled with food (peanuts or fruit) is mounted on the shaft of the stepper motor, like a throttle value, so turning it half a revolution allows the food to fall into a trough where the chimps can access it.


It sits flush against the fence on the opposite side from the chimps. Designing it with no large gaps means that the chimps fingers cannot get a proper hold of it and tear it to shreds. Various types of disk make up the puzzle, some rotating and some not, some with just a slot for carrying the token and some with paths cut out. The disks are mounted on a removable board using wing nuts so that they can be easily removed or replaced by the keeper, this allows them to adjust the complexity of the puzzle ensuring the chimps don’t get bored as well as making it easy to clean.


I was responsible for the electronics while my group built the rest of the prototype and CAD.