7 ms·

Show HN: Open-Source eInk Bike Computer

423 points by stingrae 13d ago

Hey all, i just launched my Eink Bike computer project and think it is cool. Another tidbit, in the crazy things that AI has done... It has helped create a ANT (common sensor wireless protocol used in workout/biking) implementation for ESP32 by messing around with undocumented registers: https://github.com/RaemondBW/esp32-ant https://github.com/RaemondBW/esp32-ant

zsoltkacsandi 12d ago
I've found e-ink displays super fragile for this use case. They break from a little fall, or even from the constant shaking.
- orbital-decay 12d ago
  For all their readability benefits under direct sunlight, prolonged exposure also damages or kills them. You need at least a UV blocker for outdoor use, but the heat cannot be avoided.
kccqzy 13d ago
Wow. You managed to receive ANT+ via BLE hardware?! I didn't know these two protocols were so similar.
- stingrae 13d ago
  yes. they luckily the same phy, 1 Mbit/s GFSK modulation.
- woodgala 12d ago
  The protocols aren’t the same by the physical link is. Same with 802.15.4 aka thread aka zigbee.
arpanghoshal07 13d ago
great!
evrimoztamur 13d ago
I can't imagine using this in the Netherlands with random rain. The tradeoffs are hard to accept, wondering how it looks and performs in various weather conditions, and if a physical buttoned shell is worth it...
- matsemann 12d ago
  Garmin Edge 10X0 series is touch only (except for pause and lap button). Was a bit apprehensive myself moving to 1040 from my old 5X0 series with buttons only, but no issues in weather so far. More reliable than a phone display with droplets.
- Finnucane 12d ago
  I gave up on bike computers years ago after a couple of tries to find one that would survive New England winter. Then I realized I didn't really need to give a crap about anything a bike computer was telling me.
- consp 12d ago
  My experience with touch is it works ok as long as you do some arbitrage. I've implemented four touch quadrants on my display and it works good enough in the rain (quadrants are linked to play/pause/next etc for music) that it doesn't do anything I don't want it to do. Only downside is sometimes it misses a hit in the rain. Weather sealing is quite doable if you accept you need a boatload of glue and you coat your 3d printed case with proper car lacquer or at least a thick coat of acryl. Use reinforced filament, and at least something 70c+ resistant (so no ordinary PLA). I've driven it plenty in the rain in NL (not this display, my own).
dinan 13d ago
Does this work well in direct sunlight? I know a lot of e-paper panels struggle to refresh in strong sunlight. The waveshare panels look very faded if they update while exposed to UV.
- stingrae 13d ago
  i have ridden with this unit over five hundred miles and not had any issues. though SF Bay Area summers arent as tough as other places.
- carlosjobim 12d ago
  Maybe they get air cooled if you pedal fast enough?
tuchsen 13d ago
Hey this looks neat, I’ve been thinking on trying something similar. I’ve not encountered the ANT protocol, what bike ya using? Is it a higher level thing that your display is giving you, or something your controller uses? I know Bafang uses CAN protocols in their newer e-bike systems and a lot of manufacturers (especially Chinese) use a proprietary UART protocol to stitch things together on the cheaper end. The mess of different implementations makes it really hard to hack on and share this kinda stuff. AI does make it really easy to figure out these protocols now so that’s nice I guess. I just flipped my bike upside down and hooked up a logic analyzer and it took LLM no time to figure it out… it is really impressive
- monknomo 13d ago
  ant+ is a garmin protocol that is very common with fitness gadgets and in the bike world. It's a bit like bluetooth, but lower energy usage.
  - jeffbee 12d ago
    It also got nuked from orbit by European regulators. The ecosystem has a huge installed base but no future.
    - Brian_K_White 12d ago
      Isn't it only using standard ble hardware anyway? So what's the problem?
      - jeffbee 12d ago
        They are both using the same physical layer, but the ANT+ protocol scheme is more amenable to ultra-low-power implementations than BLE is. The European belief that my wheel rotation sensor needs privacy through encryption has effectively outlawed the low-power attributes of ANT+ for future hardware.
        speedgoose 12d ago
Lucasoato 13d ago
Any open source GPS locator for bikes?
- consp 12d ago
  Cheap chinese tracker, prepaid sim and traccar instance? That's what mine has.
pilina 13d ago
Battery of my Cubot King Kong Mini is slowly dying. I use it with OpenTracks to record my commutes and use as bikecomputer and sometimes Osmand+ for offline navigation. I am searching for alternative, which needs to be waterproof and cheap (my commutes luckily includes downhill trails sometimes - I dont want to break expensive device). The title gave me high hopes, but I suppose I need to keep searching.
dumbmachine 13d ago
Wow, this is really cool. I really needed something for my neo retro build, this might just fit the bill.
maxrev17 13d ago
Insane! Quality on the ANT too!
memoryfault 13d ago
I love this. How do you house & secure your lily on your bike?
mholt 13d ago
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 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.
- robot_jesus 12d ago
  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!
  - matsemann 12d ago
__mharrison__ 12d ago
Very cool. I was messing around vibe-coding an HR monitor on a LilyGo T5. My thought was I'd love to set an HR zone and then connect it to my e-MTB and have it change power to keep me in a zone. The refresh rate on my device was horrible, and the models (this was a few months ago) struggled to create a historical line plot of my HR.
seemaze 12d ago
Would love to see video of the application in action. Was recently researching eink displays for motorcycle navigation, but the refresh rates were not up to par for realtime automotive navigation..
- stingrae 12d ago
  i have been using it in my car during commutes for testing. modern eink displays can do pretty high refresh rates. i think i can hit 20hz.
Rebelgecko 12d ago
The semi-interactive walkthrough on the website is really cool, great way to show the UX. I've always wanted to use a round display and an 18650 to plop a mini bike computer into my headset (replacing the cap). There was a Kickstarter years ago for a project doing that, but it seems to have fizzled out
- pandaman 12d ago
  If you mean that you push a 18650 inside the steerer tube and have the display at the cap level - how do you preload the headset then? You need to pull the steerer up somehow and it's done via that cap and a bolt that goes through it into a compression plug/star nut inside the steerer. If you place something under the cap it needs to fit between that bolt and the inside of the steerer tube, which 18650 can't.
  - ehnto 12d ago
    Some modern headset designs don't use the top cap to do that. There's a bunch of products that exploit that to put toolkits, spare CO2 canisters or whathave you in that spot.
    - pandaman 12d ago
      Sure, threaded headsets (hardly modern, but they do still make bikes with those) don't use top cap, but they also don't have a hole at the top, which products you are talking about? PS. I searched and found some in-steerer storage. It's not a headset but essentially a hollow compression plug replacement with a top cap moved to the bottom. I have never seen a road fork with a hole at the bottom so it is likely limited to MTB forks and, since there is no compression in that thing, it might be not very safe with a carbon steerer.
      - lostlogin 11d ago
        Frame storage is my dream feature for a road bike. You see it on gravel bikes and it makes me very jealous.
wiether 12d ago
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 right in front of you The cons of eInk: - refresh rate -> yeah, I don't want the map display to be laggy - visibility in the dark -> tunnels, tree cover... I don't want to my GPS to be invisible - lack of color -> colors provide lots of information on the map display Anyway, as long as you have fun doing this and some people enjoy it also, congrats!
- 30minAdayHN 12d ago
  I agree. But this could be a fun and cheap project to do with kids for their bikes :)
- flutas 12d ago
  IMO at least a better one to do would be a transflective LCD like the original pebble watches used.
  - Gigachad 12d ago
    That’s what most bike gps screens are now.
  - kccqzy 12d ago
    I already have a transreflective screen on my current mass-produced bike computer. I don’t see a need to make another one, whereas I’ve never seen an eInk one; I think that’s genuinely cool and the main innovation here.
  - scottbez1 12d ago
    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
jeffbee 12d ago
This is cool, but I bet it will be a grind trying to get to Garmin levels of battery life. They just have it nailed, and an Edge 550 that's ¼ this size can run for over a day, despite its emissive display, and they don't seem to suffer from display scaling since the larger Edge 1050 runs for even longer. That is to say that the larger battery in a larger device more than compensates for the higher display power requirement. Anyway one thing I think would be nice is if the GPS radio can become a peripheral. Then with that architecture could the head unit just get GPS from your phone?
- Someone 12d ago
  > and they don't seem to suffer from display scaling since the larger Edge 1050 runs for even longer Why would they suffer from display scaling? At the same device thickness, larger devices have the same volume per cm² of display. And it gets better: - if they need the same volume for electronics (likely mostly true; you may want a slightly faster CPU and more memory, but don’t need a larger GPS, second WiFi chip, etc), that means more battery volume per cm² of display. - at small sizes, I guess/expect wall thickness of the case to scale slower than the dimensions of the case, giving larger cases relatively more internal room. (Googling, I see the 550 is even slightly thicker than the 1050; 16,8mm vs 16,3mm)
  - jeffbee 12d ago
    Yes, that's my point. You might imagine an advantage for eink if you can make the display as big as you want without blowing out the power budget, but in practice it already doesn't matter.
- kccqzy 12d ago
  Only a day? COROS has it beat by having 100+ hours of GPS riding. And I think GPS is the key power consumption part here. Have you tried opening one of those background location tracking apps that would require your phone to receive GPS all day long? That significantly reduces battery life on your phone. You really want your entire GPS stack running on a power-sipping processor, not on your phone’s application processor.
neoCrimeLabs 12d ago
Within 10 seconds I was convinced I needed to try this. For me, the next step for this is taking all the sensor data recorded for a ride, and loading it into my own fitness tracking database that I own, control, and isn't tied to someone else's profits.
- rfonseca 12d ago
  intervals.icu?
  - neoCrimeLabs 11d ago
    Looks good, but unless I'm severely mistaken it's a SAAS, not self hosted. As long as it's on someone else's service I don't own it and it's not under my control. I openly admit, I have not spent much time researching this subject, was just in the back of my brain as I migrate away from SAAS and IAAS.
nickmcc 12d ago
Very cool! I made something similar recently with my Xteink X4 ereader - difference being it served as a UI for sensors connected to my phone. Getting the ESP32 to communicate directly to ANT sensors is pretty wild!
- financetechbro 12d ago
  Do you have any resources for playing around with the Xteink outside of just reading? I got mine this week and would love to push its utility!
me_online 12d ago
Funny, I just got done researching the Coros Dura, another eInk bike computer.
- stingrae 12d ago
  technically i dont think the coros uses an eink display. but it is definitely one of the cooler bike computers.
shrinks99 12d ago
Very cool! Did you consider Protomaps for the map tile format at all? It's a pretty clever way of storing everything in a single file and their tooling is pretty nice.
- stingrae 12d ago
  I hadnt heard of it. I will check it out.
  - steve_adams_86 12d ago
    PMTiles is the underlying technology I believe. We use it on oceanconnect.ca and in my opinion it’s pretty awesome. Very efficient to store and retrieve, and cut our S3 PUT request costs by something like 90% across the project.
StrLght 12d ago
Wow, this looks amazing! I hope we can get a better suited hardware though. Larger buttons, smaller device overall. 4.7" sounds huge, almost size of a phone.
- stingrae 12d ago
  yes me too. i may be working on something...
bruce_wayne_ 12d ago
Damn, this looks cool
Mathieu_UpCard 12d ago
[dead]
insane_dreamer 12d ago
awesome stuff. I have a Wahoo bike comp but would love to use an OSS alternative the dealbreaker for me is whether it could eventually work with the Garmin Vario radar (which the Wahoo supports with a nice visualization) -- that is _literally_ a life saver and I no longer ride without it.
- dddw 12d ago
  I also have a wahoo. Pretty great. Especially its week of batterylife
hi_hi 12d ago
There’s no mention of the wheel sensor. How does it get the bike telemetry?
- dchest 12d ago
  GPS
- _kb 12d ago
  Since the ANT+ protocol implementation seems to already be there, it seems a likely/sensible future path is to implement wheel sensor support. It provides much higher accuracy of speed/distance than GPS and lower power draw. On that note, this is a world I've recently taken a dive in to. I was about to roll a Pi Zero / ESP data logger to track distance travelled on my commuter bike for planning service intervals. Was keen on a solution that didn't involve draining a phone battery and remembering to start trips, a full bike computer, or smartwatch. After a bit of research I picked up a Garmin Speed Sensor 2 - highly recommend as a bit of stupidly effective tech. The device straps around your hub and is essentially a coin battery and mems rotation sensor. In addition to running as an ANT+ peripheral it will operate standalone and log the last 300 hours of ride time then sync next time you open the app. Speed and distance is then inferred based on wheel circumference.
  - hi_hi 10d ago
    I really appreciate this info. I went old school when I hacked my own esp32 bikeputer together with a wheel magnet and reed switch. It was fun to put together, but pretty janky with wires tapped up and it wouldn’t survive any off-roading. I wasn’t aware of the more modern ANT+ approach. Looking forward to a V2.
lostlogin 12d ago
Wow, amazing work. My use case is a bit more basic than most. I am nearly always on routes I know and just want a few basic stats, but… I require a bike radar to work. I use a Varia. I like the beep, and need the indication for a car behind. Is there any compatibility with this? If this question is already answered somewhere, apologies.
vilas900420 12d ago
[flagged]
dongking 12d ago
This exchange is fantastic! I was immediately impressed, and I'm eager to try it out with my bicycle.
rjrjrjrj 12d ago
Cool project. Not sure I'd use it, as my iPhone works quite well for this purpose. iPhones have had always on display since the 14 Pro and 17, and they've had good water resistance since forever. No problem reading it under any conditions. - iPhone 15 Pro with quadlock case - various Quadlock mounts - Quadlock mag charging mount with a USB C battery in the top tube bag for long rides - Apple Watch (paired to SRAM Powermeter on bike) - Record rides using Apple Fitness on Apple Watch - Apple fitness syncs to Strava and other services - Ride With GPS, Apple Maps, or Google Maps for turn-by-turn (when necessary)
- stingrae 12d ago
  be careful how you mount it, make sure that there is enough dampening. people have had issues with excessive vibration and damaging the OIS and focusing motors in the cameras.
  - rjrjrjrj 12d ago
    Thanks, hasn't been a problem for me. ~15,000km with this phone. Tens of thousands more on older phones all the way back to the 5s. Which of course wasn't nearly as good: no always-on display and had to use the Quad Lock "poncho" in the rain.
    - asdff 12d ago
      My road bike handlebars killed my iphone camera fwiw. Into the saddlebag it goes now.
  - belZaah 12d ago
    Quadlock makes a special dampening mount for this reason.
grbi 12d ago
Great project. I'm tired of all the brands that stops updates ect. Do you have a mounting system already ?
jbj 12d ago
This would be a pair great with Gadgetbridge and Endurain. https://gadgetbridge.org/ https://gadgetbridge.org/ https://endurain.com/ https://endurain.com/
PreownedPlaid 12d ago
[flagged]
Ninn 11d ago
Love the project and progress made, along with the ESP32 ANT! But to be more involved and support a project like this I really would need it to be based on a board with proper weather resistance! Hope you find that as an option in the future.
godelski 11d ago
This is great. One suggestion I have (for these types of projects in general) is to include a BoM and price estimates. Make those front and center. Even though prices shift they give people ballpark estimates for deciding "do I want to spend time on this" or not. It also shows a log of clearly supported hardware and even makes it easier to track tweaks for different hardware as people contribute to your projects.
woodgala 11d ago
Excellent job! I had no idea about the LilyGo platform. Amazing. I was just in the market for a Garmin cycle computer and I will absolutely give this a go. Thanks!
poulpy123 11d ago
Wow that's nice ! I especially like that you clearly explain the tradeoffs. One surprised me though: > No pressure sensor. There’s no barometric altimeter, so climbing is derived from elevation baked into the map tiles rather than measured — total ascent is an estimate. The gps from the device do not provide the altitude or is it not precise enough ?
v1ne 11d ago
Why eInk? The display updates often, that's a perfect choice for Sharp MIP displays. Also: Please use a fixed-width font for numbers. Seeing the values wobble around looks like a generic website, not like a serious product.

423 points by stingrae 13d ago

zsoltkacsandi 12d ago

I've found e-ink displays super fragile for this use case. They break from a little fall, or even from the constant shaking.

orbital-decay 12d ago
For all their readability benefits under direct sunlight, prolonged exposure also damages or kills them. You need at least a UV blocker for outdoor use, but the heat cannot be avoided.

kccqzy 13d ago

Wow. You managed to receive ANT+ via BLE hardware?! I didn't know these two protocols were so similar.

stingrae 13d ago
yes. they luckily the same phy, 1 Mbit/s GFSK modulation.
woodgala 12d ago
The protocols aren’t the same by the physical link is. Same with 802.15.4 aka thread aka zigbee.

arpanghoshal07 13d ago

great!

evrimoztamur 13d ago

I can't imagine using this in the Netherlands with random rain. The tradeoffs are hard to accept, wondering how it looks and performs in various weather conditions, and if a physical buttoned shell is worth it...

matsemann 12d ago
Garmin Edge 10X0 series is touch only (except for pause and lap button). Was a bit apprehensive myself moving to 1040 from my old 5X0 series with buttons only, but no issues in weather so far. More reliable than a phone display with droplets.
Finnucane 12d ago
I gave up on bike computers years ago after a couple of tries to find one that would survive New England winter. Then I realized I didn't really need to give a crap about anything a bike computer was telling me.
consp 12d ago
My experience with touch is it works ok as long as you do some arbitrage. I've implemented four touch quadrants on my display and it works good enough in the rain (quadrants are linked to play/pause/next etc for music) that it doesn't do anything I don't want it to do. Only downside is sometimes it misses a hit in the rain. Weather sealing is quite doable if you accept you need a boatload of glue and you coat your 3d printed case with proper car lacquer or at least a thick coat of acryl. Use reinforced filament, and at least something 70c+ resistant (so no ordinary PLA). I've driven it plenty in the rain in NL (not this display, my own).

dinan 13d ago

Does this work well in direct sunlight? I know a lot of e-paper panels struggle to refresh in strong sunlight. The waveshare panels look very faded if they update while exposed to UV.

stingrae 13d ago
i have ridden with this unit over five hundred miles and not had any issues. though SF Bay Area summers arent as tough as other places.
carlosjobim 12d ago
Maybe they get air cooled if you pedal fast enough?

tuchsen 13d ago

Hey this looks neat, I’ve been thinking on trying something similar. I’ve not encountered the ANT protocol, what bike ya using? Is it a higher level thing that your display is giving you, or something your controller uses? I know Bafang uses CAN protocols in their newer e-bike systems and a lot of manufacturers (especially Chinese) use a proprietary UART protocol to stitch things together on the cheaper end. The mess of different implementations makes it really hard to hack on and share this kinda stuff. AI does make it really easy to figure out these protocols now so that’s nice I guess. I just flipped my bike upside down and hooked up a logic analyzer and it took LLM no time to figure it out… it is really impressive

monknomo 13d ago
ant+ is a garmin protocol that is very common with fitness gadgets and in the bike world. It's a bit like bluetooth, but lower energy usage.
- jeffbee 12d ago
  It also got nuked from orbit by European regulators. The ecosystem has a huge installed base but no future.
  - Brian_K_White 12d ago
    Isn't it only using standard ble hardware anyway? So what's the problem?
    - jeffbee 12d ago
      They are both using the same physical layer, but the ANT+ protocol scheme is more amenable to ultra-low-power implementations than BLE is. The European belief that my wheel rotation sensor needs privacy through encryption has effectively outlawed the low-power attributes of ANT+ for future hardware.
      - speedgoose 12d ago

Lucasoato 13d ago

Any open source GPS locator for bikes?

consp 12d ago
Cheap chinese tracker, prepaid sim and traccar instance? That's what mine has.

pilina 13d ago

Battery of my Cubot King Kong Mini is slowly dying. I use it with OpenTracks to record my commutes and use as bikecomputer and sometimes Osmand+ for offline navigation. I am searching for alternative, which needs to be waterproof and cheap (my commutes luckily includes downhill trails sometimes - I dont want to break expensive device). The title gave me high hopes, but I suppose I need to keep searching.

dumbmachine 13d ago

Wow, this is really cool. I really needed something for my neo retro build, this might just fit the bill.

maxrev17 13d ago

Insane! Quality on the ANT too!

memoryfault 13d ago

I love this. How do you house & secure your lily on your bike?

mholt 13d ago

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 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.

robot_jesus 12d ago
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!
- matsemann 12d ago

__mharrison__ 12d ago

Very cool. I was messing around vibe-coding an HR monitor on a LilyGo T5. My thought was I'd love to set an HR zone and then connect it to my e-MTB and have it change power to keep me in a zone. The refresh rate on my device was horrible, and the models (this was a few months ago) struggled to create a historical line plot of my HR.

seemaze 12d ago

Would love to see video of the application in action. Was recently researching eink displays for motorcycle navigation, but the refresh rates were not up to par for realtime automotive navigation..

stingrae 12d ago
i have been using it in my car during commutes for testing. modern eink displays can do pretty high refresh rates. i think i can hit 20hz.

Rebelgecko 12d ago

The semi-interactive walkthrough on the website is really cool, great way to show the UX. I've always wanted to use a round display and an 18650 to plop a mini bike computer into my headset (replacing the cap). There was a Kickstarter years ago for a project doing that, but it seems to have fizzled out

pandaman 12d ago
If you mean that you push a 18650 inside the steerer tube and have the display at the cap level - how do you preload the headset then? You need to pull the steerer up somehow and it's done via that cap and a bolt that goes through it into a compression plug/star nut inside the steerer. If you place something under the cap it needs to fit between that bolt and the inside of the steerer tube, which 18650 can't.
- ehnto 12d ago
  Some modern headset designs don't use the top cap to do that. There's a bunch of products that exploit that to put toolkits, spare CO2 canisters or whathave you in that spot.
  - pandaman 12d ago
    Sure, threaded headsets (hardly modern, but they do still make bikes with those) don't use top cap, but they also don't have a hole at the top, which products you are talking about? PS. I searched and found some in-steerer storage. It's not a headset but essentially a hollow compression plug replacement with a top cap moved to the bottom. I have never seen a road fork with a hole at the bottom so it is likely limited to MTB forks and, since there is no compression in that thing, it might be not very safe with a carbon steerer.
    - lostlogin 11d ago
      Frame storage is my dream feature for a road bike. You see it on gravel bikes and it makes me very jealous.

wiether 12d ago

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 right in front of you The cons of eInk: - refresh rate -> yeah, I don't want the map display to be laggy - visibility in the dark -> tunnels, tree cover... I don't want to my GPS to be invisible - lack of color -> colors provide lots of information on the map display Anyway, as long as you have fun doing this and some people enjoy it also, congrats!

30minAdayHN 12d ago
I agree. But this could be a fun and cheap project to do with kids for their bikes :)
flutas 12d ago
IMO at least a better one to do would be a transflective LCD like the original pebble watches used.
- Gigachad 12d ago
  That’s what most bike gps screens are now.
- kccqzy 12d ago
  I already have a transreflective screen on my current mass-produced bike computer. I don’t see a need to make another one, whereas I’ve never seen an eInk one; I think that’s genuinely cool and the main innovation here.
- scottbez1 12d ago
  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

jeffbee 12d ago

This is cool, but I bet it will be a grind trying to get to Garmin levels of battery life. They just have it nailed, and an Edge 550 that's ¼ this size can run for over a day, despite its emissive display, and they don't seem to suffer from display scaling since the larger Edge 1050 runs for even longer. That is to say that the larger battery in a larger device more than compensates for the higher display power requirement. Anyway one thing I think would be nice is if the GPS radio can become a peripheral. Then with that architecture could the head unit just get GPS from your phone?

Someone 12d ago
> and they don't seem to suffer from display scaling since the larger Edge 1050 runs for even longer Why would they suffer from display scaling? At the same device thickness, larger devices have the same volume per cm² of display. And it gets better: - if they need the same volume for electronics (likely mostly true; you may want a slightly faster CPU and more memory, but don’t need a larger GPS, second WiFi chip, etc), that means more battery volume per cm² of display. - at small sizes, I guess/expect wall thickness of the case to scale slower than the dimensions of the case, giving larger cases relatively more internal room. (Googling, I see the 550 is even slightly thicker than the 1050; 16,8mm vs 16,3mm)
- jeffbee 12d ago
  Yes, that's my point. You might imagine an advantage for eink if you can make the display as big as you want without blowing out the power budget, but in practice it already doesn't matter.
kccqzy 12d ago
Only a day? COROS has it beat by having 100+ hours of GPS riding. And I think GPS is the key power consumption part here. Have you tried opening one of those background location tracking apps that would require your phone to receive GPS all day long? That significantly reduces battery life on your phone. You really want your entire GPS stack running on a power-sipping processor, not on your phone’s application processor.

neoCrimeLabs 12d ago

Within 10 seconds I was convinced I needed to try this. For me, the next step for this is taking all the sensor data recorded for a ride, and loading it into my own fitness tracking database that I own, control, and isn't tied to someone else's profits.

rfonseca 12d ago
intervals.icu?
- neoCrimeLabs 11d ago
  Looks good, but unless I'm severely mistaken it's a SAAS, not self hosted. As long as it's on someone else's service I don't own it and it's not under my control. I openly admit, I have not spent much time researching this subject, was just in the back of my brain as I migrate away from SAAS and IAAS.

nickmcc 12d ago

Very cool! I made something similar recently with my Xteink X4 ereader - difference being it served as a UI for sensors connected to my phone. Getting the ESP32 to communicate directly to ANT sensors is pretty wild!

financetechbro 12d ago
Do you have any resources for playing around with the Xteink outside of just reading? I got mine this week and would love to push its utility!

me_online 12d ago

Funny, I just got done researching the Coros Dura, another eInk bike computer.

stingrae 12d ago
technically i dont think the coros uses an eink display. but it is definitely one of the cooler bike computers.

shrinks99 12d ago

Very cool! Did you consider Protomaps for the map tile format at all? It's a pretty clever way of storing everything in a single file and their tooling is pretty nice.

stingrae 12d ago
I hadnt heard of it. I will check it out.
- steve_adams_86 12d ago
  PMTiles is the underlying technology I believe. We use it on oceanconnect.ca and in my opinion it’s pretty awesome. Very efficient to store and retrieve, and cut our S3 PUT request costs by something like 90% across the project.

StrLght 12d ago

Wow, this looks amazing! I hope we can get a better suited hardware though. Larger buttons, smaller device overall. 4.7" sounds huge, almost size of a phone.

stingrae 12d ago
yes me too. i may be working on something...

bruce_wayne_ 12d ago

Damn, this looks cool

Mathieu_UpCard 12d ago

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insane_dreamer 12d ago

awesome stuff. I have a Wahoo bike comp but would love to use an OSS alternative the dealbreaker for me is whether it could eventually work with the Garmin Vario radar (which the Wahoo supports with a nice visualization) -- that is _literally_ a life saver and I no longer ride without it.

dddw 12d ago
I also have a wahoo. Pretty great. Especially its week of batterylife

hi_hi 12d ago

There’s no mention of the wheel sensor. How does it get the bike telemetry?

dchest 12d ago
GPS
_kb 12d ago
Since the ANT+ protocol implementation seems to already be there, it seems a likely/sensible future path is to implement wheel sensor support. It provides much higher accuracy of speed/distance than GPS and lower power draw. On that note, this is a world I've recently taken a dive in to. I was about to roll a Pi Zero / ESP data logger to track distance travelled on my commuter bike for planning service intervals. Was keen on a solution that didn't involve draining a phone battery and remembering to start trips, a full bike computer, or smartwatch. After a bit of research I picked up a Garmin Speed Sensor 2 - highly recommend as a bit of stupidly effective tech. The device straps around your hub and is essentially a coin battery and mems rotation sensor. In addition to running as an ANT+ peripheral it will operate standalone and log the last 300 hours of ride time then sync next time you open the app. Speed and distance is then inferred based on wheel circumference.
- hi_hi 10d ago
  I really appreciate this info. I went old school when I hacked my own esp32 bikeputer together with a wheel magnet and reed switch. It was fun to put together, but pretty janky with wires tapped up and it wouldn’t survive any off-roading. I wasn’t aware of the more modern ANT+ approach. Looking forward to a V2.

lostlogin 12d ago

Wow, amazing work. My use case is a bit more basic than most. I am nearly always on routes I know and just want a few basic stats, but… I require a bike radar to work. I use a Varia. I like the beep, and need the indication for a car behind. Is there any compatibility with this? If this question is already answered somewhere, apologies.

vilas900420 12d ago

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dongking 12d ago

This exchange is fantastic! I was immediately impressed, and I'm eager to try it out with my bicycle.

rjrjrjrj 12d ago

Cool project. Not sure I'd use it, as my iPhone works quite well for this purpose. iPhones have had always on display since the 14 Pro and 17, and they've had good water resistance since forever. No problem reading it under any conditions. - iPhone 15 Pro with quadlock case - various Quadlock mounts - Quadlock mag charging mount with a USB C battery in the top tube bag for long rides - Apple Watch (paired to SRAM Powermeter on bike) - Record rides using Apple Fitness on Apple Watch - Apple fitness syncs to Strava and other services - Ride With GPS, Apple Maps, or Google Maps for turn-by-turn (when necessary)

stingrae 12d ago
be careful how you mount it, make sure that there is enough dampening. people have had issues with excessive vibration and damaging the OIS and focusing motors in the cameras.
- rjrjrjrj 12d ago
  Thanks, hasn't been a problem for me. ~15,000km with this phone. Tens of thousands more on older phones all the way back to the 5s. Which of course wasn't nearly as good: no always-on display and had to use the Quad Lock "poncho" in the rain.
  - asdff 12d ago
    My road bike handlebars killed my iphone camera fwiw. Into the saddlebag it goes now.
- belZaah 12d ago
  Quadlock makes a special dampening mount for this reason.

grbi 12d ago

Great project. I'm tired of all the brands that stops updates ect. Do you have a mounting system already ?

jbj 12d ago

This would be a pair great with Gadgetbridge and Endurain. https://gadgetbridge.org/ https://gadgetbridge.org/ https://endurain.com/ https://endurain.com/

PreownedPlaid 12d ago

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Ninn 11d ago

Love the project and progress made, along with the ESP32 ANT! But to be more involved and support a project like this I really would need it to be based on a board with proper weather resistance! Hope you find that as an option in the future.

godelski 11d ago

This is great. One suggestion I have (for these types of projects in general) is to include a BoM and price estimates. Make those front and center. Even though prices shift they give people ballpark estimates for deciding "do I want to spend time on this" or not. It also shows a log of clearly supported hardware and even makes it easier to track tweaks for different hardware as people contribute to your projects.

woodgala 11d ago

Excellent job! I had no idea about the LilyGo platform. Amazing. I was just in the market for a Garmin cycle computer and I will absolutely give this a go. Thanks!

poulpy123 11d ago

Wow that's nice ! I especially like that you clearly explain the tradeoffs. One surprised me though: > No pressure sensor. There’s no barometric altimeter, so climbing is derived from elevation baked into the map tiles rather than measured — total ascent is an estimate. The gps from the device do not provide the altitude or is it not precise enough ?

v1ne 11d ago

Why eInk? The display updates often, that's a perfect choice for Sharp MIP displays. Also: Please use a fixed-width font for numbers. Seeing the values wobble around looks like a generic website, not like a serious product.