The object of this project is to establish a remote babysitting system exploiting the portable feature of Android tablet and sensors of Phidgets. A prototype application has been implemented to demonstrate the idea.
The system mainly contains two parts, Phidget sensors (Figure 1) with a motor that can be placed as a decoration in baby's room; and an application on Android tablet.
Figure 1 - Indoor Light, Sound and Temperature Sensors Attached on a Toy
Light and temperature sensors are respectively designed for checking whether the light intensity and room temperature are suitable for baby to sleep in. The sound sensor is used for detecting whether the baby has woken up and is crying.
On Android tablet, three different ways for visualizing these physical information have been implemented. Blinking stars are shown when the light intensity is ‘low’ to represent the night mode; otherwise, a gradually formed sun is shown for day mode.
Sound values are represented by successive half-transparent rectangles, and their heights indicate the real-time volume. Normal volumes are shown in black, while ‘high’ volumes are marked in red.
For temperature, it is indicated by a dynamic filled colour box. When the temperature is ‘low’, it shows cool colours, like blue or dark purple to simulate the cold feelings; when the temperature becomes higher, it changes to warm colours, like red and orange.
All ‘low’ and ‘high’ values are relative, and are defined by thresholds, which can be adjusted by users through seek bars. Threshold value and actual sensor value are separately placed after and below seek bar for easier comparison and making decisions. Values over the threshold will cause the circle indicator turning from green to red. Furthermore, a system sound will ring on a three seconds interval and a message will be sent to notification centre. Since users cannot make sure to keep the screen active all the time, this feature is also enabled when screen is locked.
The whole system contains two programs respectively working as the server and the client to achieve the ‘remote’ feature. Data transferring between Phidgets and Android is implemented using sockets, and it requires both devices are under the same Wi-Fi network.
After several tests, the result shows that this method performs accurately and efficiently for remote data transferring. One defect is that sensors are sensitive, the rate of mistakenly triggering alerts is relatively high. However, as the acceleration of life paces, people tend to perform multiple tasks simultaneously, thus a product with the feature for remote controlling can have high market potentials for further development.
