Introduction: Betty and Eddy
Betty will take care of your household. Betty keeps an eye on your food supplies and reminds you to buy things when you walk by the grocery store.
If you are too busy to shop yourself, Betty will prepare a weekly shopping list and send it to the next grocery delivery service. Eddy analyzes your eating habits and warns when you consume too much chocolate or too less beer.
Step 1: Prepare a Grocery Stand
We took a bendable plastic as a stand for the products. We attached an accelerometer to its base (the other side of the stand) as shown in the figure.
This accelerometer is connected to the breakout board which is available in the Grove Starter Kit.
As the plastic stand bends, the accelerometer changes its static position. This generates the change in the 3-axis accelerometer reading according to the gravitational force.
Step 2: Attach a Touch Switch
Attach a touch switch to the stand and connect it to the grove break out box.
This switch is used for calibration of the bottle and product weight. This is done by the following process :
1. Single-tap on the touch is used to measure the change caused by placing an empty bottle.
2. A double-tap on the touch is used to indicate that the bottle with filled contents is placed on the stand.
The two information obtained will be used in the subsequent processes.
Step 3: Prepare the Galileo Board With OS and Wireless Module
A wireless card is attached to the back of the Galileo board. The mini-SD-Card is pre-loaded with YOCTO (A linux based OS). The Galileo is booted up using the procedures shown in the tutorials of Galileo. The WiFi is enabled and connected to internet as shown in the Galileo documentation.
Using EnableIOT dashboard, the two sensors are registered on the internet platform.
Step 4: Use the Sensor Information on a Mobile
Using the enableIOT API, read the information from the sensors - Touch and Accelerometer.
Whenever there is a single touch, update the information of the bottle accelerometer signal reference..
Whenever there is a double touch, update the information of the filled-bottle accelerometer signal reference..
Whenever the accelerometer signal is only 10% of the difference between the two reference signals offset from the empty bottle reference, the user shall be indicated that the contents of the bottle are soon going to be empty.
The logic behind:
The bendable stand bends depending on the weight of the object placed on it. This bending changes the accelerometer reading because the component of gravity varies accordingly.
This direct co-relation between the weight and the accelerometer values obtained by the bending of the stand is used to compare if the contents of the bottle are getting empty.