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My senior design project for mechanical engineering was swapping lead acid batteries in an electric skateboard for nickel metal hydride (2008 lithium battery pr

My senior design project for mechanical engineering was swapping lead acid batteries in an electric skateboard for nickel metal hydride (2008 lithium battery prices were not within a college budget). It gave me a new found appreciation for battery tech and I still feel a bit like they’re incomprehensible magic boxes. My proudest part of the project was: we didn’t have money for high end voltage or current recording devices and the amps of the thing was quite high. I zip tied a volt meter and an analog current gauge to a piece of plywood, then we mounted a 2x4 at a 90 degree angle and attached a camera to that. We used that setup to take video when we were riding. It let us correlate the time and other units together. By watching the video and manually recording the results into a spreadsheet. Not fast or high precision but it worked well and most importantly was within budget.

tomtranter 2y ago
Nice! I love the simple approach like the story which I'm not sure if it's true or not that NASA spent $$$ developing an ink pen that would work in zero-g and the Russians used a pencil.
- vgivanovic 2y ago
  Hmmm. What about the pencil shavings? Makes me wonder if the story is true.
  - 10u152 2y ago
    Aerosolised conductive dust (carbon) is not something you want on a spaceship
- sitkack 2y ago
  https://www.snopes.com/fact-check/the-write-stuff/ https://www.snopes.com/fact-check/the-write-stuff/
- Max-q 2y ago
  The Russians used a simple, standard ballpoint pen, so the story is not true
  - pkaye 2y ago
    The Russians eventually ended up using the same pen that NASA did. It pen was developed by a private company and sold to both of them at $2.39/ea.
- rfdave 2y ago
  That's an urban legend. https://www.scientificamerican.com/article/fact-or-fiction-nasa-spen/ https://www.scientificamerican.com/article/fact-or-fiction-n...
- tomtranter 2y ago
  Yeah I thought so but like most legends contains a kernel of truth and is certainly worth remembering for the lesson. Reminds me of the midwit meme https://www.ycombinator.com/library/IW-dalton-michael-elon-musk-and-the-midwit-meme https://www.ycombinator.com/library/IW-dalton-michael-elon-m...
barrenko 2y ago
They certainly are magic boxes!
sitkack 2y ago
Now that we have DMMs that have QR code displays you don't need to manually transcribe. All joking aside, I have generated telemetry data and displayed via a QR code for exactly this application. Documenting here as prior art so it can't be patented. A system and method for displaying time series data from any data-generating device as a Quick Response (QR) code, enabling efficient data extraction from video recordings. This invention facilitates the capture and analysis of time series data without manual transcription across a wide range of applications.
- toss1 2y ago
  Can you publish details (or a link thereto) to solidify the prior art? IIRC, not only the fact of success but also the methods used must be published to establish prior art. One of the best ways to do this may be to file a Provisional Patent application. It costs $100, and is a write-up of the outline and methods/technology used. The patent office does nothing but leave it in a drawer. If you file a proper patent application referencing it within 365 days, then it becomes part of the new patent and holds your priority date. If you don't then the contents of the Provisional Patent app becomes public domain - now fully and authoritatively documented public domain.
- pjc50 2y ago
  This is a genius idea .. although I wonder how it competes with OCR against the 7-segment display.
  - pastage 2y ago
    Depends, we managed to OCR all pixels from a standard 128x64pixel OLED. Doing 20 kB/s as a debugging interface was marvelous. Someone smart used the mounting holes on the screen to mount a fixed Finder pattern (the squares in QR Codes), and it was almost fool proof. So Yeah you can easily do seven segment displays now days.
  - sitkack 2y ago
    I used Teodora Baluta's Linux Kernel Oops QR code generator as inspiration. https://www.linuxfoundation.org/blog/blog/opw-intern-develops-qr-code-for-linux-kernel-oops-messages https://www.linuxfoundation.org/blog/blog/opw-intern-develop... With a QR code you get self describing data streams, ECC, links to manuals.

tomtranter 2y ago

Nice! I love the simple approach like the story which I'm not sure if it's true or not that NASA spent $$$ developing an ink pen that would work in zero-g and the Russians used a pencil.

vgivanovic 2y ago
Hmmm. What about the pencil shavings? Makes me wonder if the story is true.
- 10u152 2y ago
  Aerosolised conductive dust (carbon) is not something you want on a spaceship
sitkack 2y ago
https://www.snopes.com/fact-check/the-write-stuff/ https://www.snopes.com/fact-check/the-write-stuff/
Max-q 2y ago
The Russians used a simple, standard ballpoint pen, so the story is not true
- pkaye 2y ago
  The Russians eventually ended up using the same pen that NASA did. It pen was developed by a private company and sold to both of them at $2.39/ea.
rfdave 2y ago
That's an urban legend. https://www.scientificamerican.com/article/fact-or-fiction-nasa-spen/ https://www.scientificamerican.com/article/fact-or-fiction-n...
tomtranter 2y ago
Yeah I thought so but like most legends contains a kernel of truth and is certainly worth remembering for the lesson. Reminds me of the midwit meme https://www.ycombinator.com/library/IW-dalton-michael-elon-musk-and-the-midwit-meme https://www.ycombinator.com/library/IW-dalton-michael-elon-m...

barrenko 2y ago

They certainly are magic boxes!

sitkack 2y ago

Now that we have DMMs that have QR code displays you don't need to manually transcribe. All joking aside, I have generated telemetry data and displayed via a QR code for exactly this application. Documenting here as prior art so it can't be patented. A system and method for displaying time series data from any data-generating device as a Quick Response (QR) code, enabling efficient data extraction from video recordings. This invention facilitates the capture and analysis of time series data without manual transcription across a wide range of applications.

toss1 2y ago
Can you publish details (or a link thereto) to solidify the prior art? IIRC, not only the fact of success but also the methods used must be published to establish prior art. One of the best ways to do this may be to file a Provisional Patent application. It costs $100, and is a write-up of the outline and methods/technology used. The patent office does nothing but leave it in a drawer. If you file a proper patent application referencing it within 365 days, then it becomes part of the new patent and holds your priority date. If you don't then the contents of the Provisional Patent app becomes public domain - now fully and authoritatively documented public domain.
pjc50 2y ago
This is a genius idea .. although I wonder how it competes with OCR against the 7-segment display.
- pastage 2y ago
  Depends, we managed to OCR all pixels from a standard 128x64pixel OLED. Doing 20 kB/s as a debugging interface was marvelous. Someone smart used the mounting holes on the screen to mount a fixed Finder pattern (the squares in QR Codes), and it was almost fool proof. So Yeah you can easily do seven segment displays now days.
- sitkack 2y ago
  I used Teodora Baluta's Linux Kernel Oops QR code generator as inspiration. https://www.linuxfoundation.org/blog/blog/opw-intern-develops-qr-code-for-linux-kernel-oops-messages https://www.linuxfoundation.org/blog/blog/opw-intern-develop... With a QR code you get self describing data streams, ECC, links to manuals.