AI Kayak Controller Lets The Paddle Show The Way

June 10, 2024 by Dan Maloney 6 Comments

Controlling an e-bike is pretty straightforward. If you want to just let it rip, it’s a no-brainer — or rather, a one-thumber, as a thumb throttle is the way to go. Or, if you’re still looking for a bit of the experience of riding a bike, sensing when the pedals are turning and giving the rider a boost with the motor is a good option.

But what if your e-conveyance is more of the aquatic variety? That’s an interface design problem of a different color, as [Braden Sunwold] has discovered with his DIY e-kayak. We’ve detailed his work on this already, but for a short recap, his goal is to create an electric assist for his inflatable kayak, to give you a boost when you need it without taking away from the experience of kayaking. To that end, he used the motor and propeller from a hydrofoil to provide the needed thrust, while puzzling through the problem of building an unobtrusive yet flexible controller for the motor.

His answer is to mount an inertial measurement unit (IMU) in a waterproof container that can clamp to the kayak paddle. The controller is battery-powered and uses an nRF link to talk to a Raspberry Pi in the kayak’s waterproof electronics box. The sensor also has an LED ring light to provide feedback to the pilot. The controller is set up to support both a manual mode, which just turns on the motor and turns the kayak into a (low) power boat, and an automatic mode, which detects when the pilot is paddling and provides a little thrust in the desired direction of travel.

The video below shows the non-trivial amount of effort [Braden] and his project partner [Jordan] put into making the waterproof enclosure for the controller. The clamp is particularly interesting, especially since it has to keep the sensor properly oriented on the paddle. [Braden] is working on a machine-learning method to analyze paddle motions to discern what the pilot is doing and where the kayak goes. Once he has that model built, it should be time to hit the water and see what this thing can do. We’re eager to see the results.
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Extreme Waterproof 3D Prints

February 18, 2024 by Al Williams 21 Comments

Since the crew at [CPSdrone] likes to build underwater drones — submarines, in other words — they need to 3D print waterproof hulls. At first, they thought there were several reasons for water entering the hulls, but the real reason was that water tends to soak through the print surface. They’ve worked it all out in the video below.

Since the printer is an FDM printer, it isn’t surprising that the surface has tiny pores; even the tiniest pores will let water in at high pressure. They tried using epoxy to seal the prints, which worked to some degree. They did tests using an example submersible hull that you can try yourself if you like.

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A Survey Of Long-Term Waterproofing Options

March 27, 2023 by Matthew Carlson 27 Comments

When it comes to placing a project underwater, the easy way out is to just stick it in some sort of waterproof container, cover it with hot glue, and call it a day. But when you need to keep water out for several years, things get significantly harder. Luckily, [Patricia Beddows] and [Edward Mallon] from the Cave Pearl Project have written up their years of experience waterproofing data loggers for long-term deployment, making the process easier for the rest of us.

It starts with the actual board itself. Many SMD boards have at least some flux left over from the assembly process, which the duo notes has a tendency to pull water in under components. So the first step is to clean them thoroughly with an ultrasonic cleaner or toothbrush, though some parts such as RTCs, MEMs, or pressure sensors need to be handled with significant care.

Actual waterproofing starts with a coating like 422-B or nail polish which each have pros and cons. [Patricia] and [Edward] often apply coatings to PCBs even if they plan to otherwise seal it as it offers a final line of defense. The cut edges of PCBs need to be protected so that water can’t seep between layers, though care needs to be made for connectors like SD cards.

Encapsulation with a variety of materials such as hot glue, heat shrink tubing, superglue and baking soda, silicone rubber, liquid epoxy, paste epoxy (like J-B Weld), or even wax are all commented on. The biggest problem is that a material can be waterproof but not water vapor proof. This means that condensation can build up inside a housing. Temperature swings also can play havoc with sealings, causing gaps to appear as it expands or contracts.

Overall, it’s an incredible guide with helpful tips and tricks for anyone logging data underwater for science or even just trying to waterproof their favorite watch.

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The project's hardware, including the ESP32 camera module, stuffed into the GoPro-intended waterproof shell. The camera portion of the ESP32 module sticks out exactly where the GoPro's camera would be. To the left, a hacked ESP32-CAM module is shown.

Hackaday Prize 2022: Solar-Harvesting ESP32 Camera Is Waterproof, Repeatable

August 14, 2022 by Arya Voronova 1 Comment

[alberto nunez] shows off his sleek build of a solar-harvesting ESP32 camera – waterproof, somewhat energy-efficient, and able to be built by more-or-less anyone. For that, he’s chosen fairly jellybean components – an ESP32-CAM module with a matching protoboard, a small solar cell, a LiFePO4 battery, and a waterproofed GoPro shell that all of these parts neatly fit into.

A BQ25504 energy harvesting chip is used to ensure the ‘solar’ part of the project can meaningfully contribute to the project’s power budget, with energy otherwise mainly provided by the LiFePo4 battery. Since this battery’s nominal voltage is 3.2 V, it can be wired straight to ESP32’s power input and there’s no need for a regulator – thus, that one got mercilessly desoldered. [alberto] has also modded the board using a FET to gate power to the ESP32-CAM module’s camera, with all of these hacks bringing the board’s deep sleep current from 2.8 mA to 0.8 mA. Not great for a low-power device, but not terrible for something you can build so easily. Plus, it’s waterproof, dust-resistant, and quite robust!

These ESP32 camera modules are seriously nifty – we see them put to good use on the regular. Whether you need to detect motion in your Halloween project, decode your water meter readings, or perhaps merely a security camera, it’s worth having a few in your toolbox. Maybe even pick up a programming helper for these while you’re at it!

Surfboard Gets Jet Upgrades

November 25, 2021 by Bryan Cockfield 6 Comments

Surfing is a fun and exciting sport but a lot of beginners can get discouraged with how little time is spent actually riding waves while learning. Not only are balance and wave selection critical skills that take time to learn, but a majority of time in the water is spent battling crashing waves to get out past the breakers. Many people have attempted to solve this problem through other means than willpower alone, and one of the latest attempts is [Andrew W] with a completely DIY surfboard with custom impeller jet drives.

The surfboard is hand-made by [Andrew W] himself using a few blocks of styrofoam glued together and then cut into a generic surfboard shape. After the rough shaping is done, he cuts out a huge hole in the back of the board for the jet drive. This drive is almost completely built by [Andrew] as well including the impeller pumps themselves which he designed and 3D printed. The pair of impellers are driven by some beefy motors and a robust speed controller that connects wirelessly to a handheld waterproof throttle to hold while surfing. Once everything was secured in the motor box the surfboard was given a final shaping and then glassed. The final touch was an emergency disconnect attached to a leash so that if he falls off the board it doesn’t speed away without him.

The build is impressive not only for [Andrew]’s shaping skills but for his dedication to a custom jet drive for the surfboard. He spent over a year refining the build and actually encourages people not to do this as he thinks it took too much time and effort, but we’re going to have to disagree with him there. Even if you want to try to build something a lot simpler, builds like these look like a lot of fun once they’re finished. The build seems flawless and while he only tested it in a lake we’re excited to see if it holds up surfing real waves in an ocean.

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Truck Bed Liners Improve 3D Prints

February 14, 2021 by Al Williams 27 Comments

There are at least two kinds of 3D printer operators: those who work hard to make their prints look better after they come off the bed and those who settle for whatever comes off the printer. If you are in the latter camp, you probably envy people who have smooth prints with no visible layer lines. But the sanding and priming and multiple coats of paint can put you off.

[Teaching Tech] has a few tricks that might change your mind. He shares his technique for using different coatings for 3D prints that provide good quality with a lot less effort. The coatings in question are polyurethane used for coating pickup truck beds and bitumen rubber used for waterproofing. In the United States, bitumen is known as asphalt, and both materials are relatively cheap, available, and safe to use.

According to the video you can see below, there’s no need to sand or prime the print. In addition to covering imperfections and sealing gaps, it produces watertight prints that have UV resistance and some measure of protection against heating.

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Hackaday Links: March 22, 2020

March 22, 2020 by Dan Maloney 23 Comments

Within the span of just two months, our world of unimaginable plenty and ready access to goods manufactured across the globe has been transformed into one where the bare essentials of life are hard to find at any price. The people on the frontline of the battle against COVID-19 are suffering supply chain pinches too, often at great risk to their health. Lack of proper personal protective equipment (PPE), especially face masks, is an acute problem, and the shortage will only exacerbate the problem as healthcare workers go down for the count. Factories are gearing up to make more masks, but in the meantime, the maker and hacker community can pitch in. FreeSewing, an open-source repository of sewing patterns, has a pattern for a simple face mask called the Fu that can be made quickly by an experienced threadworker. Efficacy of the masks made with that pattern will vary based on the materials used, obviously; a slightly less ad hoc effort is the 100 Million Mask Challenge, where volunteers are given a pattern and enough lab-tested materials to make 100 face masks. If you know how to sew, getting involved might make a difference.

As people around the world wrap their heads around the new normal of social distancing and the loss of human contact, there’s been an understandable spike in interest in amateur radio. QRZ.com reports that the FCC has recorded an uptick in the number of amateur radio licenses issued since the COVID-19 outbreak, and license test prep site HamRadioPrep.com has been swamped by new users seeking to prepare for taking the test. As we’ve discussed, the barrier for entry to ham radio is normally very low, both in terms of getting your license and getting the minimal equipment needed to get on the air. One hurdle aspiring hams might face is the cancellation of so-called VE testing, where Volunteer Examiners administer the written tests needed for each license class. Finding a face-to-face VE testing session now might be hard, but the VEs are likely to find a way to adapt. After all, hams were social distancing before social distancing was cool.

The list of public events that have been postponed or outright canceled by this pandemic is long indeed, with pretty much everything expected to draw more than a handful of people put into limbo. The hacking world is not immune, of course, with many high-profile events scuttled. But we hackers are a resourceful bunch, and the 10th annual Open Source Hardware Summit managed to go off on schedule as a virtual meeting last week. You can watch the nearly eight-hour livestream while you’re self-isolating. We’re confident that other conferences will go virtual in the near-term too rather than cancel outright.

And finally, if you’re sick of pandemic news and just want some escapist engineering eye candy, you could do worse than checking out what it takes to make a DSLR camera waterproof. We’ve honestly always numbered cameras as among the very least waterproof devices, but it turns out that photojournalists and filmmakers are pretty rough on their gear and expect it to keep working even so. The story here focuses (sorry) on Olympus cameras and lenses, which you’ll note that Takasu-san only ever refers to as “splash-proof”, and the complex system of O-rings and seals needed to keep water away from their innards. For our money, the best part was learning that lenses that have to change their internal volume, like zoom lenses, need to be vented so that air can move in and out. The engineering needed to keep water out of a vented system like that is pretty impressive.