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Prototype can now be worn

A project log for TIRO Vibrating Watch

TIRO (Time is Running Out) is a watch that vibrates every few minutes to remind the user that time in this world is quickly running out.

accidentalrebelAccidentalRebel 03/18/2019 at 07:340 Comments

The first prototype for the TIRO Watch (Time is Running Out) can now finally be worn and tested under real world conditions. It looks ugly and too pink right now, but aside from that everything works!

After wearing the prototype I immediately noticed how weak the vibration of the motor was. This makes sense because the vibration motor now needs to vibrate while attached to the back side of the casing not unlike when it was vibrating freely when it was running on a breadboard.

A quick fix I made was that I removed the Resistor 1 in the circuit (At 47 ohms) and placed a wire in it's place (See below image). This made the vibration stronger making it easier to notice. A downside to this change is that the current draw will increase. I have not measured it but based on previous experiments it should be around 20mA more.

Another thing I did was I tried to come up with a quick hack to hold the CR2032 coin cell battery (Also seen on same image above). I initially went with just bare wires and wrapping the ends with electrical tape but it was not good as the ends tend to get loose easily. I then had this bright idea of using crimp terminal connectors as the contacts and wrapped them with electrical tape. It's better than just the wires but a more cleaner solution would be to wrap with a heatshrink. I currently don't have one available that could fit the battery so this would do for now.

Also, there currently isn't any way to turn the circuit off to conserve power. This can easily be solved with a simple on and off slider switch in between the battery and the rest of the circuit. It's ugly, but it's the easiest to insert within the circuit without needing to change the whole thing.

So far the prototype is running quite well. I'll be continuing to improve this design until I feel it's ready to be in PCB form.

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