User manual

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It will lead to error such that, the counter will be negative value or the counter
will never decrease to zero. Counter will be negative due to failure of detecting an
occupant entering the door. In this case, lighting is turned off even there is an
occupant left inside the laboratory. While the other side, counter will never decrease
to zero once the system failed to detect a visitor that leaving the room. Therefore,
even if the last person leaving the room, there is remainder one occupant considered
by counter that is not leaving due to the previous error even there are no more
occupants left inside the laboratory.
Figure 4.7 : Counter show negative value
The second problem is the counter will ignore if a visitor stand in between the
sensor or one of them. This means, once occupant stand in between the door, buzzer
will beep indicates error, and the occupant have no choice but to step back. If an
occupant failed to do so, it will lead to the unreliable of this system to operate
properly.
The sensor did not detect the height of occupant accurately. The data varies
even the same person pass through the system. It might be inability of IR proximity
sensor to detect the actual range of the occupant. This problem may be due to the
limit of the range of detection. By doing some analysis, it is concluding that the
sensor gives less efficient output to microcontroller when it detects the black and
gross surface. An assumption made that the light intensity at the surrounding of the