|60||Automated Tea Brewing Thermos
|Our project for this class will be an automatic tea making thermos. This thermos will have two different mechanisms to control tea brewing. One of which controls the steeping temperature of the tea you would like to brew. Using a simple switch or a Bluetooth connected device, we can choose to steep at two different temperatures, since there are only two major temperature points used in brewing the common teas*. In addition to this there will be another control for switching between weak, medium, and strong tea. These features are built referencing a guide for tea*. To achieve these basic features a RTD temperature sensor will be added to the inside of the thermos between the outer wall and inner wall of the thermos to check if the steeping temperature has been reached. There is no need to regulate this temperature either, since most steeping temperatures come with a wide enough range where thermal loss considerations are not needed. In addition, a timer will be pre-set, based on user input, for how long to steep the tea based on the saturation level desired. To automate this process these sensor inputs will be conveyed to a motor that will raise and lower the teabag into the water like an anchor. The motor will attach itself to the teabag string with a clip to account for the variations of tea bags. The microcontroller, PCB, and motor will be mounted onto/into the handle to keep the water and heat away from the electronics. With the centralized location to the side of the thermos we plan on building a waterproof enclosure with the use of rubber gaskets, and epoxy to allow for partial submersion under water for hand washing. This design also takes mobility into consideration and allows you to carry the mug wherever you go. We are going to add a heating unit to the bottom of the thermos which will contain a pair of nickel-chromium wires which will serve as heating coils. Their heating output (voltage across coils) will be determined by the micro controller. Once the selected tea and strength have been selected by either the switches or your Bluetooth connected device the thermos will be turned on and heat up to the desired temperature then shut off its heating coil and begin brewing. Once it has finished brewing the controller will provide an audible ding for the user. In addition, the user will be able to follow three LED lights to see what stage of the brewing process the tea is in. (heating up, steeping, and finished). Lastly the user can view a temperature readout display to see what the current temperature in the thermos is. All of this will run on a Li-ion battery which will also be mounted onto the side of the thermos and be rechargeable.