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Show HN: Open-Source eInk Bike Computer

opentrailpaper.com

51–60 of 127 posts

Re: Show HN: Open-Source eInk Bike Computer

#51
post #23

I love my eInk displays, I love my bike head unit. But I don't see how they both fit together honestly. The pros of eInk: - low energy usage -> don't matter, current GPS units have +30 hours of battery life already - low eye strain -> don't matter, you don't look at the screen for hours at a time - visibility -> don't matter, current GPS units adapt to ambient light - angle visibility -> don't matter, the screen is r…

This device has a backlight enabled by a physical button, and navi refresh rate doesn't matter because you're riding and not staring at it. 1Hz is fine for a reference. Not sure why needing less battery or having better at-a-glance visibility would be such a bad thing. One need not love a device, that's ok. But digging to invent a reason to hate it also doesn't seem necessary.

Refresh rate does kind of matter. 1Hz imposes an average 0.5s latency on any update, which would be obnoxious in some situations.

Re: Show HN: Open-Source eInk Bike Computer

#54
post #34
post #23

I love my eInk displays, I love my bike head unit. But I don't see how they both fit together honestly. The pros of eInk: - low energy usage -> don't matter, current GPS units have +30 hours of battery life already - low eye strain -> don't matter, you don't look at the screen for hours at a time - visibility -> don't matter, current GPS units adapt to ambient light - angle visibility -> don't matter, the screen is r…

IMO at least a better one to do would be a transflective LCD like the original pebble watches used.

Heh, I just got a waveshare RLCD to play with sunlight visible higher refresh rate, but then I compared it side by side with the exact e-paper display for this project and I felt buyer’s remorse; the contrast is soooo much worse on the LCD.

Maybe it would have fared better if I was out in sunlight viewing them, but seeing this thing in person sold me on e-paper for this use case

Re: Show HN: Open-Source eInk Bike Computer

#55
post #42
post #39

Earlier quoted context omitted.

> 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 is like a piece of paper, which gets MORE visible in the sun, but standard touchscreen LCDs/OLEDs get harder to see. I am not sure about the physics/reasons for this. Phones also aggressively dim screens to conserve energy and lower temperatures. Phones absorb a lot of sunlight, so a white eInk display is brilliant in that regard. Refresh rate is a solved problem for eInk as well, but it comes with energy tradeo…

Trying to outbright the sun on a battery-powered device is an approach I've always found questionable.

E-ink, instead just lets the sun reflect off of it, does want some sort of light in the dark, but, perfectly visible in full-bright/direct sunlight.

Re: Show HN: Open-Source eInk Bike Computer

#57
post #34
post #23

I love my eInk displays, I love my bike head unit. But I don't see how they both fit together honestly. The pros of eInk: - low energy usage -> don't matter, current GPS units have +30 hours of battery life already - low eye strain -> don't matter, you don't look at the screen for hours at a time - visibility -> don't matter, current GPS units adapt to ambient light - angle visibility -> don't matter, the screen is r…

IMO at least a better one to do would be a transflective LCD like the original pebble watches used.

That’s what most bike gps screens are now.

Re: Show HN: Open-Source eInk Bike Computer

#58
post #39
post #15

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/sta…

> 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.

LCD screen are pitch black by default. Eink can be white without extra energy

Re: Show HN: Open-Source eInk Bike Computer

#59
post #23

I love my eInk displays, I love my bike head unit. But I don't see how they both fit together honestly. The pros of eInk: - low energy usage -> don't matter, current GPS units have +30 hours of battery life already - low eye strain -> don't matter, you don't look at the screen for hours at a time - visibility -> don't matter, current GPS units adapt to ambient light - angle visibility -> don't matter, the screen is r…

Well said. I don't understand who this would be for.

Re: Show HN: Open-Source eInk Bike Computer

#60
post #15

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/sta…

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.

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