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.
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!
Apparently current GPS screens are compatible with your eyes and the viewing conditions you find yourself in. Congrats! May your eyes never darken and your trails be easy!
For others, some of those advantages do matter. Different strokes for different folks! Cheers mate.
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.
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 and I think that’s genuinely cool and the innovation here.
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
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.
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?
Thanks; not yet unfortunately, I have been too busy to set up a mailing list, but that's a good idea.
The video preview I linked to only shows the rich maps and instrument modes. There's also a wireframe map view that is higher-contrast and much more practical for your gravel rides: https://i.imgur.com/lZF20Xz.png -- and I am still tuning of course, we can make the map smaller and the characters larger, etc.
Maybe follow @mholt6 on X for updates when I have them... whenever Apple will let me in.
In my humble experience the gold standard for bike computer screens was the Wahoo Elemnt Roam 2. It had like 64 colors or so but you could see it everywhere.
That being said, seeing that there are now eink displays capable of 60Hz, I wish they (and projects like this one) could take over in this specific market.
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 tradeoffs and... might still be proprietary. But 60-120 fps eInk exists AFAIK.
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..
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
ANT+ is basically dead because of an EU legal requirement to ensure that personal information is encrypted. So no new devices will be supporting it, and everything has to move to BLE.
It was quite a rich ecosystem of sensor devices, especially for cycling, including speed and cadence sensors, heart rate monitors, power meters, lights, radar, etc.
It has been extremely popular over the last 20 years.
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!
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.
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...
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.
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.
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.
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.
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?
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.
> 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)
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.
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.
I love my eInk displays, I love my bike head unit.
But I don't see how they both fit together honestly.
Anyway, as long as you have fun doing this and some people enjoy it also, congrats!For others, some of those advantages do matter. Different strokes for different folks! Cheers mate.
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.
IMO at least a better one to do would be a transflective LCD like the original pebble watches used.
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 and I think that’s genuinely cool and the innovation here.
I agree. But this could be a fun and cheap project to do with kids for their bikes :)
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
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.
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!
Thanks; not yet unfortunately, I have been too busy to set up a mailing list, but that's a good idea.
The video preview I linked to only shows the rich maps and instrument modes. There's also a wireframe map view that is higher-contrast and much more practical for your gravel rides: https://i.imgur.com/lZF20Xz.png -- and I am still tuning of course, we can make the map smaller and the characters larger, etc.
Maybe follow @mholt6 on X for updates when I have them... whenever Apple will let me in.
> 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.
In my humble experience the gold standard for bike computer screens was the Wahoo Elemnt Roam 2. It had like 64 colors or so but you could see it everywhere.
That being said, seeing that there are now eink displays capable of 60Hz, I wish they (and projects like this one) could take over in this specific market.
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 tradeoffs and... might still be proprietary. But 60-120 fps eInk exists AFAIK.
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..
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
ANT+ is basically dead because of an EU legal requirement to ensure that personal information is encrypted. So no new devices will be supporting it, and everything has to move to BLE.
It was quite a rich ecosystem of sensor devices, especially for cycling, including speed and cadence sensors, heart rate monitors, power meters, lights, radar, etc.
It has been extremely popular over the last 20 years.
Ant+ is for connecting sensors and other stuff. Like heart rate monitor, power meter, control resistance on a trainer etc.
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.
It also got nuked from orbit by European regulators. The ecosystem has a huge installed base but no future.
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.
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!
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!
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.
Wow. You managed to receive ANT+ via BLE hardware?! I didn't know these two protocols were so similar.
yes. they luckily the same phy, 1 Mbit/s GFSK modulation.
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...
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.
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.
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.
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.
Wow, this is really cool. I really needed something for my neo retro build, this might just fit the bill.
I've found e-ink displays super fragile for this use case. They break from a little fall, or even from the constant shaking.
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.
Insane! Quality on the ANT too!
I love this. How do you house & secure your lily on your bike?
Any open source GPS locator for bikes?
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?
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.
> 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)
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.
Funny, I just got done researching the Coros Dura, another eInk bike computer.
great!