DEVICE COMPONENTS
CONCEPT
The spoon is capable of producing four different tastes when used. When completed with a regulating button, the user can switch between the four modes - sweet, salty, sour, bitter - to choose what they would like their food to taste like. This is controlled by an electrical circuit explained in the next section. Additionally, the spoon is also capable of emitting scents and modifying its temperature to correspond to the desired state of the food.
ELECTRICAL CIRCUIT
The electrical circuit of Electreat is a simple circuit powered by a Seeeduino Xiao. The circuit consists of two wires, connected to the 3.3 V output pin and ground pin of the Seeeduino microcontroller. The other ends of the wires are connected to two independent pieces of metal. The Seeeduino outputs a pulse-width modulated current with a duty cycle that can be set by the user based on the spoon "mode". This current travels to the metal pieces and when the spoon is placed in the mouth, the circuit is complete. The completed circuit generates a mild current in the mouth which mimics different tastes.
PHYSICAL DESIGN
The Electreat Spoon is designed using Fusion 360. A hole is made from the back of the spoon which opens up at the bottom of the handle, near the neck. The seeeduino XIAO, Peltier module, and Aroma diffuser are fitted into the hole. The wires are passed through the opening and connected to a metal plate stuck to the bottom of the spoon's bowl. The material of the 3D printed spoon is PLA which is considered food safe. This design has been made keeping hygiene and safety concerns in mind. The hole in the spoon is made watertight to prevent water from leaking in while washing the spoon. The spoon also has all electrical components secured to make cleaning easy and safe.
PELTIER MODULE AND AROMA DIFFUSERS
The Peltier Module and Aroma Diffusers are additional features in our device, which complements the circuit to enhance the tasting experience. The body engages different senses to allow the person to enjoy every part of the food. The Peltier Module and Aroma Diffusers aim to do the same; they provide heat and aroma to the mouth, ensuring that the feel of the food corresponds to the taste. Both these miniature components will be attached to the spoon and connected to the circuit.
TESTING
Testing is an important stage of Electreat. User safety is of utmost priority and we went through 3 stages of testing to ensure that. Prior to user testing, safety trials were conducted to ensure the device didn't exceed the given current or become too hot. This was tested using lab equipment such as multimeters and oscilloscopes. Once this test was safely passed, we tested the mild current on moist skin. The goal was to see the interaction of the current with a conducting human body. Lastly, we tested this circuit on 4 participants. This stage also tested the effectiveness of the taste feature. 3 of the 4 participants could feel a taste distinctly whereas one participant could feel something but was not sure what it was. The device's usability was then evaluated by the same participants, and modifications were made.
FUTURE WORK AND IMPROVEMENTS