June 9th

Planning:

Needs to register hits
- First Idea: IMU - Already have some Adafruit nrf 52840 sense boards (https://learn.adafruit.com/adafruit-feather-sense/overview) that would be great
- Other Ideas:
  - Piezo sensors - plan to hook up 4/5 to the ADCs of the nrf board for more detailed pressure/strike detection - Note: might need some voltage protection
  - FSR (Force Sensistive Resistors - A friend used these in one of their projects, but reportedly they aren't very precise, so probably won't use them.
Signalling
- LED strip around pad, neopixels embedded within pad below the fabric surface,
- Can use bluetooth for web interface
- First prototype will probably use serial while initial testing
- Power
  - The nrf sense board already have a battery hookup and charger for lipo batteries
Probably won't need a PCB just because the nrf sense boards already work so well.

Found boards, updated bootloader
Tried out the adafruit sensor demo
- Took way to long to get the correct libaries installed
- Need to note that the acceleration also includes gravity when stationary so I may need to offset that later
After that, tired out neopixel demo, needed to find correct neopixel configuration to use the onboard pin
Combined the two to make a system that reflects both the direction and magnitude of the acceleration on the IMu built into the board
- Forgot to accout for negatives, which confused me for a bit
- Squaring the values caused it to become too sensitive and also flashbang me,
- Settled on less sensitive brightness and color control, with offsets to account for stationary moments.
  - Stationary:
    - Dim and single color
  - Accelerating:
    - Much brighter and between primary colors

I talked to my taekwondo instructor and he gave me 4 old pads to experiment with
- ## Initial Testing
Shoved the sense board (feather) into the pad
- Kinda messy for a first test but if it work it works. Note will need padding to protect board from impact
Did a tad more coding, intially to use the serial plotter, but that sucks so I got a serial decoder in python and am using that for testing
It works - But now I appear to be maxing out the sensor:
- Despite hitting with different power, the accel always seems to be suspiciously similar
- Read the data sheet and it looks like the imu is set to +-4G of acceleration so I need to find a way around that.
- Ok I found a way to increase the accel range to 16g, which is the max. SAadly, I'm still maxing it on some punches, maybe i should try some padding
Padding in front of the sensor did not work, I think i need some sort of springy substance both infront and behind the sensor to act as mechanical dampers.

I made a rough case that has a space for a sliding platform with springs to dampen impact.
However, i am currently failing at both making a screw and making a spring I am using the sweep tool wrong somehow and will figure it out later

1h planning (probably a little more than this)+1h coding + 0.5h Pad Acquisition+ 2h initial testing + 1 h CADding

Time Spent: 5.5h

I really need to learn CAD for real.
I got a spring set up in possible the most awful way posible
Then for somethin reason I thought I could print this in 1 piece without supports
- I also failed at screws again so I settled for dowels
- I am also suspecting that I will need a high-G IMU like https://blog.st.com/lsm6dsv320x/
  - Its also smd so I have no shot of soldering that myself, so I'll probably need the expansion board
Slice and printed for testing

1h Cadding + 0.5h Research/Parts Search

Time Spent: 1.5h

Not too deep, everything generally fits. The dowels didn't print very well but thats fine.

Time Spent: 0.5h

Made the wiring diagram, looked through datasheets and connected everything correctly
Plan to directly solder to microcontroller due to the large distance from the micrcontroller to the peripherals
- May use a perf board if the wiring becomes too hairy.

Time Spent: 1h