Toilet Occupied Indicator - First Runner-up and Merit (Design)

By Chun Hang, LEUNG | Wai Ki, KWONG | Tsz Yin, LEE

Sometimes there is a long queue for people to wait for a toilet in a shopping mall. It will be much better if people can have more information before they queue up there so that they may quickly find an available toilet (see Figure 1). This project is to develop a toilet occupied indicator to detect the status of different toiles and provide more information for users to select an available toilet. With the help of this indicator, the toilet waiting time can be reduced.

Figure. 1

Some LED indicators are shown in Figure 2. The LEDs are used to identify whether toilets are occupied or not. Moreover, when a toilet is occupied too long, the corresponding LED blinks to alert people outside (i.e., staff) for potential danger checking (e.g., faint inside the toilet). An OLCD (organic LCD) display is installed in the system to show the queue length and the waiting time of a toilet. Moreover, it gives suggestions for people to select available toilets. A queue counting system is developed to count the number of persons in the queue. Note that we use light sensors to detect the queue length but not a camera to protect privacy. They apply the queuing theory to compute the waiting time by using the equation below:

Waiting time (in second) ={0 n<s n-s+1 μs otherwise

where n is the number of customers in the system, s is the number of servers and µ is the mean service rate.

Figure. 2

The demonstration video is shown below.

Comment by judges: The proposed idea is practical and the team can demonstrate it properly. All features can be presented in the online demonstration, especially the analytical model of the waiting time is appreciated. Moreover, they can make use of PCB DesignSpark and 3D mechanical tools properly in the demonstration model. However, the presentation skill can be further improved. It is quite difficult for audiences to follow and the presentation time is too long. Moreover, some similar applications can be found on the Internet and thus the proposed idea is not very innovative.