Designing and Testing a Smart Cat Feeder Prototype
This report describes the design process for a smart cat feeder. The main goals of the project include dispensing food on a user-set schedule, regularly weighing two cats and the food they eat, and making weight data easily available to the user via a phone application. It should be able to maintain a schedule and record distinct data for at least two different cats. This device is intended for use by busy or multiple-cat owners, and by animal shelters and veterinary offices to track cat health. The final design is Arduino-based and includes two scales: a cat weighing platform based on four strain gauge load cells which records the cat’s weight when a radio-frequency identification card attached to its collar is read, and a food bowl weighing scale based on a single strain gauge load cell which records the amount of food in the bowl to estimate how much the cat has eaten. The final dispensing mechanism uses a 4.8 L reservoir and a PVC pipe to hold and convey food to an aluminium box, which contains a 3D-printed wheel with a brush overtop to reduce jamming of the mechanism. The wheel turns on a user-set schedule in increments of 1/12th of a cup using a stepper motor. The final software design includes Arduino IDE back-end code and a Blynk-based user interface, and is capable of recording and graphing cat weight and food consumed data for two different cats. The application also allows the user to set three different feeding times and amounts. The entire device requires a single 9 V power supply to be plugged into a regular household outlet. The project outcome was semi-successful in terms of meeting goals, with major shortcomings being lower weighing accuracy than specified and a jamming percentage of 39.1%.