This is great, I just saw your post on X. I'm also building a bike computer!
eInk is the right display tech. I think this will do really well. It might need a UV filter.
That said, I don't love needing a separate device (hence, I don't own any bike computer). This is just my preference, but I really prefer to just plop my phone on my handlebars. So I'm building a bike computer app for iPhone: https://x.com/mholt6/status/2090529441944687087 (trying to get Apple to approve my developer account / business info, but they're hung up on my website of all things).
Phones are definitely not ideal in terms of display and energy use, but, I have found that with proper optimizations, energy use is a non-issue. To offset display problems, the app has several ride modes: a rich map display with 3D road or satellite view; a high-contrast wireframe map that looks great at both high and low refresh rates because it has no analog-style gauges; an instrument panel dashboard view; and a voice-only mode that has big touch zones for on-demand voice updates, using a state of the art mobile voice synthesis model. For connected radars, the app also renders radar data and has a screen like Tesla/Rivian's autonomy displays.
The app automatically manages thermals by switching modes to preserve battery life.
In my testing so far, by managing energy, making really good voice feedback, and using high-contrast screens (every mode other than the "rich" map), even a dimmed iPhone display is quite a usable bike computer in high-altitude sunlight.
But man, that eInk looks so clean and nice. Definitely the superior display! Nice work and I hope to learn some things from it!
EDIT: Woah, you got ANT+ support using BLE radio? I am not surprised that that is possible, but dang, that must have been a clever LLM.
To each their own and the e-ink computer is a neat project. But I'm personally with you on not wanting a separate device. I have my iPhone and a quad lock case I swap on for rides.
Not sure I'm 100% on board with the visual style of your interface (some of the metrics look like they'd be nearly impossible to read while riding 30mph down a gravel road) but I'd love to check it out once it's released.
Do you have a way to sign up for release email or updates for your project?
Good luck!
> eInk is the right display tech.
It's interesting and I clicked on the OP, but why? The variable ambient light conditions, refresh rate, etc would seem to favor standard LCD/etc.
Battery capacity isn't much of an issue for a small screen, and weight carried by the bicycle.
eInk does seem like an awesome choice for this to me too.
I've gone without a bike computer for the same reasons as not wanting a second device. I used my phone for years in a water proof front frame bag with a transparent cover. Usually for not more than 3 hours at a time. Only on my Pixel 7a did I end up with burn in from the Wahoo Android app's status screen, where "n/a" for not having a power meter ultimately burnt in after about 2 years, at least that's when I noticed it. Now I just go without being able to glance down and see ride stats or directions. More planning or stopping if I reroute is required, but I didn't want to damage the phone... :(
Presumably an app could cycle displayed screens, if that's what you meant by switching modes, to avoid burn in? But I really thought AMOLED was past that when I never saw it on previous phones.