# Improved Smart Pillow for Remote Health Care System
## 3 Results
### Sample Data from the Smart Pillow  
To verify the principle introduced previously, a night data sample was selected randomly from an anonymized user. Figure 12 shows the distribution of the head position from 21:00 to 08:00, and Figure 13 is the temperature value from the three sensors at the exact time. Their \(x\)-axis is the same time, for the former the \(y\)-axis is group number, and the latter is temperature value multiplied by 10. Figure 11: Simulation of the thermal distribution of the pillow. Figure 12: The distribution of the head position for a user. The two graphs are analyzed for further assessment. At the beginning of Figure 13, we observe the room temperature is about 24 \({}^{\circ}\)C as all three sensors are at a similar value. From 20:45 to about 21:30 in Figure 12, the position changes frequently and the area is wider from row 1 to row 3. However, the head is not directly on the pillow, but rather as if a cushion were put on the pillow and then the user leans on the cushion, so the position under pressure changes as a result. The temperature of the sensors does not change significantly, so this matches the condition that people would do other bedtime activities like reading or watching television before sleeping. From 22:30, it appears that the pressure focuses on the left side of pillow as the position changes between 6, 11 and 12, and T\({}_{2}\) from Figure 3 changes in a non-dramatic manner. From about 23:00, all three sensors increase sharply, so it means the user's head is on the pillow and rests on position 8 for a long time, where it is in the middle of the pillow, thus where sleep begins. In the following hour, the head position changes slightly from 8 to 9 through to 14, thus the user's head slips to the upper right, so \(T_{3}\) is in the middle that reaches a peak measurement of 36.5 \({}^{\circ}\)C. This is the closest value of CBT, and \(T_{1}\) which is on the right side of Figure 3, that increases and T\({}_{2}\) declines. At about 00:40, \(T_{2}\) values rebound when the head rests on position 1 and 11 for about 20 min. After that, T\({}_{2}\) has lesser chance to record measurements as the user is prone to sleeping on the right side of the pillow. In the following 6 h, the head shifts between the middle to the right repeatedly and just rests on position 11 for a small period. The user wakes up at about 07:30 because at the time, three sensors start dropping measurements continually without fluctuation, and the position values are no longer recorded. The longest time at one position spans 40 min at around 04:00 at position 13, so it is at the upper middle, but the middle sensor locates at the bottom middle, so the value of the sensor is unable to reach the peak measurement. As a similar situation happens at about 03:00 at position 5, the duration is too short to reach and surpass the peak measurement as well. Figure 14 is the heat map of rest-on time (minutes) versus the user group from the previous sample's nightly data. Darker shading means a longer time in the area. It is observed which area is the user's favorite spot--this can help with analyzing the user's sleeping habit if permission is given. Figure 13: The measurement of temperature for the smart pillow. One unexpected observation is that the position 2 with only a minute of rest time, the result could relate to the previous preferred principle, which is for two areas with the same number of pressure sensors being triggered, such that the previous position is preferred. For example, in Figure 7, if sensors 3, 4, 5 are triggered, 3 and 4 belongs to area 2, 4 and 5 for area 3, so if the previous position is 3, the new position is still 3, and user usually starts to sleep at the middle, where it is at position 3 or 8.