Never Forget Your Phone Again!

The idea behind my final wearable project is solve to a problem that I face almost everyday: forgetting something important at home. I often find myself in the checkout line at the store without my wallet or getting lost on the road without my phone. If you’re a forgetful person like me, this may be the answer for you.

My concept was to design a device that will make sure that I have all of my essentials items with me before I walk out of the door. The wearable object is a bracelet that alerts the user if he/she walks out the door without and important item. The bracelet would be unobtrusive and neutral so that it’s good for everyday wear. The other components of the system will include tags to place on the items that you want to keep track of and a reader that is stationed near the door that detects if all of your items are present when you leave the house. When the reader detects that an item is missing, it will communicate this to the bracelet, which would alert the use through blinking lights, vibration or sound. Each item will be assigned to a unique tag and a colored light on the bracelet, allowing the system and user to know which item(s) the user is forgetting.

Originally I planned for the system to utilize Arduino micro controllers that would communicate wirelessly through RFID. In my initial research, RFID looked like the best and most inexpensive solution for my project. As I was looking to purchase supplies though, I found that long range (1m-25m) RFID technology is quite expensive. As an alternative, I used Bluetooth to wirelessly connect the Arduinos. I found a some asset tracking solutions such as Tile and Bikn that utilize Bluetooth signals to allow users to locate tagged items from their mobile devices. Since this project did not require long distance communication, Bluetooth was the next best idea.

Here are the main design requirements and materials outlined:

– Sleek, band-like plastic/rubber bracelet

Door Station:

– Encased in a small box that can be hung on the wall or door


  • HC-06 Bluetooth module
  • Rechargeable battery pack

– Small keychain/tag

My first step was to research and purchase materials. I read that the Arduino Uno was a great starter – with this course being my first experience with Arduino, I decided to get it for the Bluetooth reader station. I went with the Arduino Pro Mini because it’s compact size. Researching Bluetooth options was much more difficult. I originally purchased the HC-06 modules, which are very popular because they are super inexpensive. However, they came with little documentation and later found that it was pre-programmed in slave mode. After realizing this, I went to Fry’s and purchased the Parallax RN-42 module. It was much more expensive, but had more capabilities and could be set to master mode.

With these initial materials (along with USB cords, jumper wires, etc), I was able to easily pair the Bluetooth modules. Getting the Arduinos to communicate took some research over serial communication and AT commands. There were extremely helpful guides on Sparkfun’s tutorial site. This part was also fairly simple, but I soon hit a roadblock when I started writing code for the master Bluetooth module. I was able to get the Bluetooths to communicate, with and serial.print functions, but not much more. If I had a few more weeks, I would hope to finish the coding as well as putting together the actual wearable object. In addition to the coding, I wasn’t able to get appropriate batteries for the bracelet and tags. Since I ran out of time, I also didn’t get to putting the components together into a wearable object.

Although I had a good understanding of how each component would communicate to the others, I didn’t have the electrical and programming knowledge to execute this fully. There wasn’t enough time to carry out the full prototype, but I’m thinking about continuing this project to at least complete the coding. It’s been interesting learning to program, and it’s definitely good practice for me as a designer to have exposure to programming languages. Ultimately, my project wasn’t successful but I’m very proud of my idea and progress that I’ve made.


Figure 1. Bracelet


Figure 2. The Bluetooth reader station


Figure 3. Tag





Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.