The TeaTime is inspired by the the Electric Kettle and the Kuerig, and the ever present love for hot drinks. The TeaTime is a small object, whose purpose is to perch on your mug and tell you if your coffee temperature is acceptable for drinking via colored light. This simple device eliminates those horrible moments of sipping and expecting to get yummy tea/coffee — only to get a burnt mouth, or a disgustingly cold liquid!
TeaTime uses Arduino libraries OneWire and DallasTemperature to read and convert the tempurture of the tea via the water-proof Thermistor. 160*F or higher is dangerous, brief contact can cause significant scald burns, and is shown by the color red; 155*F is still very hot, but sippable, and is shown by the color orange; 136*F is the overall optimal drinking temperature, and is shown by the color green; 125*F is drinkable, but cooling off quickly, and is shown by the color blue; 100*F (near body-temp)is too cool for enjoyment, and is shown by the color white. These temperatures are shown via an RGB LED, useing seven different States and map() functions due to the uneven differences in state ranges.
COLD: white, 100 and lower; COOL: near white -> blue, 101 to 125; MEH: near blue -> green, 126 to 133; PERFECT: green, 133 to 140; CAUTION: near green -> orange, 141 to 155; HOT: near orange -> red, 156 to 160; and DANGER: red, 161 and higher. The current output State is determined by the READ State function, which determine what range temp falls under to produce the correct color. READ is processed each loop run-through, unless the piezo(vibration) element hasn’t felt a significant movement in a while, at which point the State is set to REST, which turns off the LED to preserve power, until another significant vibration is felt.
- 1 – Thermistor (shown as a Temp Sensor LM35
- 1 – 10K ohm resistor
- 1 – Piezo Element
- 1 – 1M ohm resistor
- 1 – RGB LED
- 3 – 200 ohm resistors