The objective of designing this system was to reduce water waste and save it when people use showers in the water park. So, we designed this device.

The device is the first part of a system. The system consists of 3 main parts, an RFID reader, a server, and a PLC. We designed an RFID reader. This device is responsible get the closed tag's data and then sending its data to the server via TCP/IP protocol when the server asks for it. Every device has a unique IP address therefore the server can ask for their data individually. There are 65 readers and the whole process of getting their data is under 12ms. 

There were many challenges when we were designing this device. First and foremost, the humidity was our most important priority. Apart from the water itself, there was also water steam. So, we used an IP65 enclosure and waterproof connectors. The next problem was the range of the RFID reader to detect a tag. The ordinary readers in the market did not have enough range for our usage, so we made a new reader with a redesigned antenna that could detect tags from a 20cm distance.

Since then all of the 65 readers are working well 724.

How it works

Every time a user closes his/her tag to the RFID reader, it gets the tag's data and waits for the server's request. The server asks all readers for their data by using their IP address. Then the reader sends the tag data to the server and the server process that data and decide if the user is eligible to use the shower or not (based on his/her previous usage). After that, it sends a command to PLC and PLC turns ON/OFF the electrical valve of the corresponding shower.

By using this system everyone can use showers for a specific time and if they need to use more, they should pay for that. Therefore the total water consumption would decrease.