DIY Free Diving Computer Feedback

[ggalisky]

Hello freedivers,

My friend and I recently finished the first prototype of a freediving computer. We won 2nd place in the makeMIT 2021 hackathon for our work (link: https://devpost.com/software/d3pth).

We won a little bit of prize money and we are putting the money back into the project. Before we design our next circuit boards I wanted to get the free diving communities feedback on what features are important to them in a free diving watch.

Our current feature list:

• Full color 240X240 pixel circular screen
• Buttonless IMU based user interface
• ESP32 Pico Microcontroller
• Wireless Charging
• Underwater compass mode utilizing the Bosch IMU
• Haptic feedback for in dive depth monitoring
• Dive logging including dive time, depth, temperature and compass headings
• Wireless dive log export over bluetooth

We want to get as much feedback as we can before we spend the money and time to design the next version.

Thank you!

 

[vrokhlenko]

I suggest having an ability to toggle a screen that shows depth and dive time in a maximum size font and nothing else. Unless you already have it. For some older divers and spearfishers it is a challenge to find a mask to compensate with eyesight issues and bifocal masks are expensive. People with perfect vision have difficulty relating to this problem. I for example have an optical lens in my right eye and normal lens in my left to have an ability to see at distance and read my computer at the same time. So font size to get info at a glance is very important to me. Just a thought

 

[J Campbell]

I'd like to have countdown timer for doing my 1-breath CO2 tables. My Oceanic F10 has a useless countdown timer that only counts down in minutes, not seconds, at it does not repeat. What I'd like is for it to countdown in minutes:seconds and then beep at the end, and then automatically restart a new countdown. That way I can set it for, say 1:15 minutes, and then do a series of breath holds each 1:15 and not have to restart it after each hold.
A loud beep that you can actually hear through a neoprene hood would be good.
A bluetooth connection so you can download data without a cable.
A rechargeable battrery so you don't have to open it up and risk seal leakage with every battery change - wireless charging would be ideal.
Thanks!

 

[7BDiver]

• A fat finger friendly wrist band that can be easily fastened with 5 mil gloves on.
• A sweet MADE IN USA label on the back .
• Perhaps a easy access large button for logging a snapshot of all parameters for significant events like personal best, injury, blood shift...
• Real time or end avg rate of descent/ascent would be really cool but only for pure glory.

 

[Mr. X]

For me, a very large font - for the reasons somebody above already mentioned - and the option to just display one , may be two, figures. For me, last/current downtime would be of most interest, followed by Max depth of last/current dive. I have a rough idea of depth from my float-line.

Less important: I'd like to be able to upload the data to my Windows PC or Android phone (e.g. Bluetooth, WiFi) to retain as a log and to view a graphic summary.

Without the very large font though, I would never buy such a device because I couldn't read it.

Traditional strap pins, so can use3rd party straps e.g. cheap, robust "NATO" strap.

 

[Jetboy]

I was going to give feedback, but everyone beat me to my ideas! Looks like you have a good thing going here. Excited to see it!

 

[camposartu]

Affordable price would be number 1.

The feature I like the best on my current dive computer, and would suggest for yours is, calculating the surface rest time based on the last dive time.
Just a peak at the screen and I can see how much I should rest. Love it.
Rechargeable battery would be cool as well.

 

[marco15499]

Nice! Congrats!

 

[SDC79]

Hi Grayson,

Thanks for posting. As well as a lot of the suggestions above, I would say that if you want to offer something that no-one else (to my knowledge) has, provide a fully customisable layout. To explain: you have a screen of certain dimensions, and you have a number of possible fields, e.g., depth, clock time, dive time (duration), rest time, temperature, etc. Different people are interested in different data on different dives and different days - I don't care about depth or temperature in the pool, and I don't want a screen full of tiny values when diving in dark water, etc., so I'd quite like to be able to pick my display arrangement to suit the needs of that particular dive.

If you were to provide simple software to allow me to move whichever fields I'm interested in around, resize them, change their colour, and perhaps set up rules about haptic, audio and/or visual feedback according to situation, I would absolutely buy that watch (provided it's rated to a good depth). I appreciate that it would almost certainly mean having to increase the resolution of the screen, but it'd be something unique.

I hope that makes sense. If you have any questions, please feel free to ask.

Regards,

Sam.

 

[camposartu]

Hi Grayson,

Thanks for posting. As well as a lot of the suggestions above, I would say that if you want to offer something that no-one else (to my knowledge) has, provide a fully customisable layout. To explain: you have a screen of certain dimensions, and you have a number of possible fields, e.g., depth, clock time, dive time (duration), rest time, temperature, etc. Different people are interested in different data on different dives and different days - I don't care about depth or temperature in the pool, and I don't want a screen full of tiny values when diving in dark water, etc., so I'd quite like to be able to pick my display arrangement to suit the needs of that particular dive.

If you were to provide simple software to allow me to move whichever fields I'm interested in around, resize them, change their colour, and perhaps set up rules about haptic, audio and/or visual feedback according to situation, I would absolutely buy that watch (provided it's rated to a good depth). I appreciate that it would almost certainly mean having to increase the resolution of the screen, but it'd be something unique.

I hope that makes sense. If you have any questions, please feel free to ask.

Regards,

Sam.

SOLID!!!!

 

[ggalisky]

This is killer feedback! I am carefully reviewing all of it and typing up a new requirements page to help guide the design process of the next version. When it is done I will reach out to some of you to perform beta testing.

It seems that a user configureable graphics user interface (GUI) is something dive watch companies have missed. It should be doable on the software side to implement this.

The only two features that are really expensive (from a commercial perspective) to add are bluetooth and wireless charging. I will need to get the watch certified by the FCC as an “intentional emitter” and I will need to get the charging dock certified as well which will cost 20-30K USD. I may skip wireless charging and use a percertified Bluetooth module to keep the FCC cost down to $1-2K USD.

 

[SDC79]

This is killer feedback! I am carefully reviewing all of it and typing up a new requirements page to help guide the design process of the next version. When it is done I will reach out to some of you to perform beta testing.

It seems that a user configureable graphics user interface (GUI) is something dive watch companies have missed. It should be doable on the software side to implement this.

The only two features that are really expensive (from a commercial perspective) to add are bluetooth and wireless charging. I will need to get the watch certified by the FCC as an “intentional emitter” and I will need to get the charging dock certified as well which will cost 20-30K USD. I may skip wireless charging and use a percertified Bluetooth module to keep the FCC cost down to $1-2K USD.

Sounds like a plan. It's not a feature per se, but please make sure you test it (or have others test it) in dark water, e.g., murky lakes, etc., where you can barely see anything. Everything's so much easier with good visibility! I'm in the U.K., so probably not a good choice of tester, but if you can't find anyone who freedives in low visibility who's willing to test it for you, just give me a shout on here.

Thinking about it, it might also be a good idea to ask some spearfishing types for their views. I don't go spearfishing myself, but it might be that they have some particular requirements, e.g., bottom time, perhaps. If you don't know any or none reply to this thread (maybe they already have), let me know and I'll ask some friends of mine.

Also, it'd be pretty cool to have a speed of ascent/descent field - it might turn out to be useful for checking glide speed!

 

[Bernie]

Hello freedivers,

My friend and I recently finished the first prototype of a freediving computer. We won 2nd place in the makeMIT 2021 hackathon for our work (link: https://devpost.com/software/d3pth).

We won a little bit of prize money and we are putting the money back into the project. Before we design our next circuit boards I wanted to get the free diving communities feedback on what features are important to them in a free diving watch.

Our current feature list:

• Full color 240X240 pixel circular screen
• Buttonless IMU based user interface
• ESP32 Pico Microcontroller
• Wireless Charging
• Underwater compass mode utilizing the Bosch IMU
• Haptic feedback for in dive depth monitoring
• Dive logging including dive time, depth, temperature and compass headings
• Wireless dive log export over bluetooth

We want to get as much feedback as we can before we spend the money and time to design the next version.

Thank you!

Absolutely excellent work, well done!

Are you looking for testers, code reviewers, or additional software developers? This sounds like a great project I would be happy to help with in my free time.

 

[xristos]

I use the ascent - descent speed on my watch all the time when freediving. When im spearfishing i will reach a depth then move in the bottom with small change in depth this makes ascent descent speed useless because its skewed. Maybe a spearfishing mode with some software could solve this most of the times still dont think its worth the hassle though.

Bluetooth is the #1 feature that makes this unique. Othr dive computers need cables not included and price them too much.

You could consider o2 saturation SpO2 or heart rate but again probably too much.

You definitely should consider protection especially for spearfishing. Those protective films like the ones for smartphones work great for me at least i would definitely include, they are so cheap but a big fuss for people to go find in the market if you dont include it with the watch( i found one made for some garmin fitness watch that fit).

Avoid the big rubber protection like cressi watches give with their computers its really bad in my opinion because the viewing angle gets reduced a lot and the rubber screen isnt readaBle after some use (too foggy).

 

[Gab]

Hello freedivers,

My friend and I recently finished the first prototype of a freediving computer. We won 2nd place in the makeMIT 2021 hackathon for our work (link: https://devpost.com/software/d3pth).

We won a little bit of prize money and we are putting the money back into the project. Before we design our next circuit boards I wanted to get the free diving communities feedback on what features are important to them in a free diving watch.

Our current feature list:

• Full color 240X240 pixel circular screen
• Buttonless IMU based user interface
• ESP32 Pico Microcontroller
• Wireless Charging
• Underwater compass mode utilizing the Bosch IMU
• Haptic feedback for in dive depth monitoring
• Dive logging including dive time, depth, temperature and compass headings
• Wireless dive log export over bluetooth

We want to get as much feedback as we can before we spend the money and time to design the next version.

Thank you!

Hey G. Galiski!

Great idea! Here is my list of features (copy-pasted from my blog post):

The killer features nobody has but that I want​

• Rechargeable battery: I don't care if it lasts only 3-4 days on a charge, that is enough. With all those smart watches running Android, powerful CPUs and lots of RAM I'm surprised it seems so hard to do...
• Better screen: I don't want color, I am talking of a good grey-scale screen with a nice resolution so you can create a nice user interface. E-Ink could be a good choice.
• Alarms:
  • Why limit it to 2 or 3, this should allow you to add as many as you want
  • Alarm types: Fixed depth, Dive time, Hydration (remind you to drink!), Surface recovery time.
  • Vibration/haptic alarms: yes, yes, YES! Smart watches can do it why not a dive watch? I would actually feel it and know an alarm went off, no missing alarms anymore. I NEVER hear my alarms (but I assume fish do)! With a nicer user interface you could setup the different alarms to vibrate differently for example.
• Wireless charging and data transfer: look mom, no hands! Seriously, just put the watch on it's charge pod when done diving and it charges, hook up the charge pad using the USB cable to the PC and you can download the data via NFC, easy, smartphones can do it and it means no need for external connectors. You could even tap your watch to your phone to download the data directly to your phone using NFC. Also Usuuport Bluetooth.
• Make it look a bit nicer, like the Suunto Elementum Aqua, Motorola Moto 360, Ratio iDive Free Avantgarde or even the Suunto D6i Novo.
• OTC Software updates, it's 2021 people, cars, phones, TVs & smartwatches can do it why not a dive watch. If would need to connect to the internet through a smartphone using bluetooth. At least you no longer need a crappy Windows-only application to do your updates.
• Better navigation: a better menu navigation system, at least better buttons that you don't need to exert a huge amount of force to press with gloves. You could have IMU touch screen maybe, if the screen is big enough.
• User programmable apps (nice to have): so users can make O2/CO2 tables and anything else you may want.
• Taravana prevention algorithm: tissue saturation, hypoxia, dehydration. Used to determine the minimum surface recovery time.
• Better Surface Recovery Timer/alarm: give the user a choice, either using the above Taravana prevention algorithm or use the last dive's data to determine the amount of rest time needed. A fixed surface recovery times is not very smart or useful. You could have a configurable lower-bound minimum for added safety if you wish, but waiting 2 minutes because you dove 30s does not make sense, so you end up ignoring it, which is more dangerous. It may make sense to take into account several dives and have a more complicated algorithm, but a doctor should have input in this.
• Standard Opensouce Dive program: make it work with Subsurface
• Sensors:
  • Oxymeter: heart rate and optimally the oxygen saturation (also used with the Taravana prevention algorithm)
  • GPS: you can plot your dives, tag locations, etc.
  • Temperature
  • Compa
• Exportable Dive data:
  • Global : total session time, total surface time, total dive time, number of dives, global max depth, global mean depth, min/max water temperature
  • Per dive : suggested recovery time (using either the taravana or dynamic algorithms, as chosen y the user), effective recovery time (the time you really spent recovering), dive time, max depth, water temperature and all the sampled data allowing you to create a graph per dive with the time, depth, water temperature, Ascent rates, GPS coordinates, heart rate, oxygen saturation

Cheers,
Gab

 

[J Campbell]

@Gab. I don't think anyone has figured out how to do an accurate O2 sensor or even heart rate monitor, underwater. Even the Apple heart rate monitor is fickle at best. If they don't work really well it would be dangerous for a freediver to rely on them.

 

[Tim B.]

Edit: Holy Shit! I just saw that you did all of that in 16 days. That is just incredible! Kudos to you & the team.

Most things have been mentioned.
Also I prefer my watch to have a regular, user replaceable battery that lasts for a year or two to be honest.

What I gladly go without:

• GPS
• O2 Sensor
• Compass
• touchscreen
• color screen
• SCUBA capabilities

What I am missing in current watches:

• customisable alarms: sound, vibration, descent and ascent
• wireless data transfer
• I know signal conduction through water is a bitch, but if there was an option to have a mini speaker for alarms in your hood, people would rip it out of your hands.
• non proprietary, easy to change, _bright neon_ wristbands or at least wristbands compatible to one of the major brands and models
• "Choose your own algorithm"
• A freediving compatible, customizable countdowntimer
• a better pool training mode (yeah, sorry. Few insights on how to achieve that apart from an accelerometer)
• More than one little rubber thingy that holds the wrist band close to itself when its closed
• Not more than 4 buttons, rather 3.
• a dedicated light button that is differently colored
• useable icons next to the buttons

What I have in my beloved Cressi Drake and would want my next watch to have as well:

• flat glass so you can have regular smartwatch screenprotectors on it
• easy access backplate removal for cleaning etc
• buttons are named
• pool training mode
• lovely EDC looks
• a sleek metal bezel
• bulletproof casing (srsly, I do take good care of my equipment, but instructor life is rough. My watch does not look like it though after 3+ years.)

That is everything I could think of in a few minutes plus the hundred times that I talked to people about dive watches in the past.

Good luck with your project mate!

 

[ggalisky]

I need to go through all these responses in more depth (get it, depth lol), but the feedback so far has been great!

As a side note if/when this project is commercialized there will be a big emphasis on user repair ability. I’m going to try to avoid double sided tapes and use screws and o rings so users can replace batteries and upload their own software if they have the time and interest.

Thank you all for the feedback so far. I will compile a list of features to explore for the next version and post it here for your review.

 

[cp1204]

Great work! I can offer some help with programming firmware and/or android app.

 

[Gab]

I

Edit: Holy Shit! I just saw that you did all of that in 16 days. That is just incredible! Kudos to you & the team.

Most things have been mentioned.
Also I prefer my watch to have a regular, user replaceable battery that lasts for a year or two to be honest.

What I gladly go without:

• GPS
• O2 Sensor
• Compass
• touchscreen
• color screen
• SCUBA capabilities

What I am missing in current watches:

• customisable alarms: sound, vibration, descent and ascent
• wireless data transfer
• I know signal conduction through water is a bitch, but if there was an option to have a mini speaker for alarms in your hood, people would rip it out of your hands.
• non proprietary, easy to change, _bright neon_ wristbands or at least wristbands compatible to one of the major brands and models
• "Choose your own algorithm"
• A freediving compatible, customizable countdowntimer
• a better pool training mode (yeah, sorry. Few insights on how to achieve that apart from an accelerometer)
• More than one little rubber thingy that holds the wrist band close to itself when its closed
• Not more than 4 buttons, rather 3.
• a dedicated light button that is differently colored
• useable icons next to the buttons

What I have in my beloved Cressi Drake and would want my next watch to have as well:

• flat glass so you can have regular smartwatch screenprotectors on it
• easy access backplate removal for cleaning etc
• buttons are named
• pool training mode
• lovely EDC looks
• a sleek metal bezel
• bulletproof casing (srsly, I do take good care of my equipment, but instructor life is rough. My watch does not look like it though after 3+ years.)

That is everything I could think of in a few minutes plus the hundred times that I talked to people about dive watches in the past.

Good luck with your project mate!

If it has a user replaceable battery instead of a rechargeable battery, then there should be a way to put the watch in sleep mode to conserve battery. It makes sense for ppl who do not have the ability to spearfish/freedive regularly. Nothing is more annoying than picking up your watch and it has a dead battery.