Ultra-Violet Girl

Inspiration

During this pandemic, one of the most dangerous things to do, is touch commonly touched surfaces such as elevator buttons, money, and especially door handles. A common solution is to wipe down those door handles one by one using corrosive chemicals which could damage door handles. This solution is ineffective, waste of manpower, and damaging to door handles!

What it does

So, I created Ms. Ultra Violet! She could sense when a door handle is being used, and KAPOW! she shoots rays of Ultra-Violet light, wiping out all the bacteria and virus goons waiting to make the next person who touches the door handle sick.

How we built it

I used an (AM312) PIR sensor to detect when the door handle has been used. When it detects usage, a microcontroller (ATTiny-13A-PU) will automatically activate two UV LEDS for 7 seconds, shining onto the door handle, killing all those nasty bacteria and viruses.
This circuit is powered by a 18650 lithium ion battery which could be recharged through a TP4056 module. I also designed the housing in CAD, and 3d printed it on my Ender 3 3d printer.

Challenges we ran into

A major problem that I had to solve was to think of a way to attach the device to the door, without causing any cosmetic damage to the door and make it easy to remove the device from the door for users to charge Ms. Ultra-Violet. My first solution was to directly attach the device onto the door with a double-sided tape. This makes it hard for users to charge their device. So, I finally figured it out to attach a latch onto the door instead. This way, users could easily slide the device off the door!

Accomplishments that we're proud of

I’m proud of the device’s consistency in detecting when a door handle is being used. Another great feature was the long battery life of over 6 months, allowing Ms. Ultra-Violet to do her job for a long time without any rest.

What we learned

I learnt a lot about the types of UV light rays – there were UV-A, UV-B, and UV-C – where UV-C has the shortest wavelength and the most energy to most effectively kill viruses and bacteria. I also learnt about how using small microcontrollers such as ATTINY-13A-PU, which I programmed through my Arduino UNO.

What's next for Ms. Ultra-Violet

Ms. Ultra-Violet will be implemented in public spaces, such as malls, schools and offices, where Ms. Ultra-Violet could save many human lives from this novel coronavirus.