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objectives >

wristLogger >

Hi-tech multi-tools are no stranger to sci-fi nerds from every universe imaginable.

I started out thinking I wanted a wrist-mounted device that could listen to and process my thoughts, but I’ve realized my full vision is a wrist-mounted multitool (that serves as a jumping off point for other wearable projects).

I get asked why I have two “watches” a lot, so might as well lean into the idea even more… wristlogger

overview of the wristLogger. wristlogger

fab practice application
laser display cover
vinyl cutter solder stencil
cncSmall PCB
3d scanning wrist/body model
cncBig gauntlet body
molding and casting overmold
output ePaper display
input pushbuttons, mic, xl
networking wifi, bt
app interface dataviz webapp for transcriptions

basic flowchart for how data will flow from user to storage/analysis wristlogger

  1. user presses button on wristLogger to start recording
  2. user talks
  3. user presses button to stop recording
  4. wristLogger sends audio file to phone for transcription
  5. phone transcribes using online or onboard service
  6. phone syncs to homelab or cloud storage
  7. service combs memos for tags and creates relationships
  8. webapp frontend used to access, edit, play with database of ideas

expanded flowchart showing alternative sensor logging applications wristlogger

finger strain sensor >

I injured my finger awhile back (06/21), and although its effectively healed, I still put strain on that finger cautiously. While undergoing physical therapy, I discovered that a strain gauge is instrumental in tracking recovery.

However, my physical therapist (a climber himself) only collected data during patient visits, which made me wonder whether it was possible to collect data on the fly, at the gym itself.

This sort of information could enable him to make better recommendations and accelerate recovery.

my makeshift splint immediately after the injury (yes, I used a house key. No, it didn’t work very well) wristlogger

a much better splint wristlogger

the idea here would be to use a minimalist strain sensor to record finger strain. However, considering its application, the challenge would be to measure strain w/o interferring with climbing itself. wristlogger

motion mapper, rope health logger >

There are many forms of climbing, but can generally be divided into rope and no-rope. One form of roped climbing, lead climbing, has the climber periodically clip the rope in as they’re climbing; they start completely free from the wall.

Falls are pretty common in lead climbing, and in fact encouraged.

However, rope has a limited lifetime, and although there are other mechanisms to check the health of rope, falls are a major contributor for rope wear. Some suggest keeping a rope usage log, but when you’re in the moment, who’s keeping track?

You learn to have a lot more fun when you don’t count your nerf darts.


electronics >

In this list, the wristLogger is probably the most mature/useful/complex design (I was on the cusp of sending it out to a board house, but ran into some issues with via manufacturability).

My design is a 4-layer board centered on the ESP32-PICO-D4, which is a 7x7mm 48-pin chip-sized module from the ESP32 family.

Fantastically capable little chip that I haven’t quite played with yet in real life.

schematics >

altium altium altium

pcb >

altium altium

the attached pdf cites credits for sources referenced during design. smartPDF file:

sequence >

what I have done:

what I haven’t done:

As you can see, not completely realized yet.

One of my biggest hurdles I’ve discovered in this class is frequently and robustly documenting my projects, so it’s only fitting that my first spiral of the class is to finish a device that will aid with documentation!

I see the following sequence:

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