Description

Team members: Isaac Lee, Nathan Ojong, Michael Son

A smart waterpack that utilizes the mbed LPC1768, an eTape Liquid Level Sensor, a DS18B20 waterproof temperature sensor, an Adafruit Bluefruit BLE board, speaker, audio amplifier, SD card reader, and uLCD display. The waterpack notifies the user via the speaker when the waterpack is full, empty, and when the user needs to drink (based on how much the user drank within a certain period of time). The uLCD displays the current water level percentage and water temperature. Water level percentage and water temperature are sent over bluetooth via the Bluefruit board, allowing for data to be monitored through the Bluefruit mobile app.

Shortcomings

Liquid level sensor only takes accurate readings while completely unbent, requiring that length of the tape be equal to the height of the water container. The waterpack being used with this hardware must also be rigid in order to allow for accurate liquid level readings. Overall, there are issues with the responsiveness of the liquid level sensor used in this design.

Without the DS18B20Z IC chip to correctly interpret temperature readings, the temperature sensor used in this design sometimes gave incorrect readings (i.e., -999.0 C).

Hardware

• mbed LPC1768
• eTape liquid level sensor
• DS18B20 temperature sensor
• Adafruit Bluefruit LE UART Friend
• Speaker
• Audio Amplifier (TPA2005D1)
• SD Card Reader
• uLCD-4DGL

Schematic

eTape liquid level sensor

DS18B20 temperature sensor

4.7K ohm resistor between VDD (white wire) and DQ (white wire).

Adafruit Bluefruit LE UART Friend

Audio Amp (TPA2005D1)/Speaker

SD Card Reader

uLCD_4DGL

Setup

Demonstration

Code