The Design

When we went into the project our original design goals were for students to wear a long range UHF RFID tag. With this students would be automatically scanned in as they passed the sensors, this is similar to what EZ-Pass toll systems utilize, we ultimately realized that this would be prohibitively expensive with cheaper sensors being in the 100-200 range with our $75 budget we knew this would be impossible. We ultimately settled on a HF RFID sensors these sensors still allowed us to use encrypted tags just like but the UHF sensors but we would end up paying only about $2 for each sensor. A limitation that these produced was that now students would have to individually scan their IDs. 

We also knew we would need some kind of internet connectivity in order to report our attendance info to SIS systems like powerschool. We had originally planned to use a simple ESP32 microcontroller, these powerful controllers boast Wifi and Bluetooth connectivity, but again we realized this may not be the best course with these readers being placed in every classroom and office throughout the school they may take up much needed Wifi bandwidth that is much needed in the modern classroom. We also thought about complexities of powering these devices as we had realized there was no power outlet in our classroom near the door. This is when we realized we could solve both of these issues with one cable. Power Over Ethernet allows our small device to connect to the internet but still be able get power at the same time. We still kept the esp32 because of its easy of use and it allows our devices to have wireless failover in case of ethernet failover. 

At this point we were confident in our plan and we put out a survey to the teachers of our school. This survey revealed issues to us that we didn't even think of. This is one response that we learn alot from "It’s really the same amount of time. The hall pass system has not really solved the excessive leaving the room that can occur. It not that I spend a lot of time dealing with this, it’s more the mental capacity required to making sure you not 1 student leaves at a time and keeping track if they were out for too long. This doesn’t take my time exactly, but it takes my cognitive ability which can leave me feeling drained." - Anonymous Hillel Yeshiva High School Teacher. With this response we realized not only should we be tracking when people leave the class room but where they go how long they go for and if one person was already out. So we added 3 buttons to our design and one light. These 3 buttons could be programmed to tell our main server what a student was going to do and then use that to track where they should go and to let the nurse or the office know they were coming. We could track if a student on the 3rd floor went to the bathroom on the other side of the school. The light was to tell you if the local bathroom was available this light would go off there was one student was already in the bathroom from that class or if there was too many people in one bathroom. Below is a Picture of our prototype at this point this was our second prototype the first just included the scanner and microcontroller without the buttons or leds. Survey Data