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.

Continue reading “Surfboard Gets Jet Upgrades” →

Extending An E-Bike Range From Good To Wheelie Good

November 15, 2021 by Matthew Carlson 25 Comments

It may not look like it in some parts of the world, but electric vehicles are gaining more and more market share over traditional forms of transportation. The fastest-growing segment is the e-bike, which some say are growing at 16x the rate of conventional bikes (which have grown at 15% during the pandemic). [Jacques Mattheij] rides an S-Pedelec, which is a sort of cross between a moped and an e-bike. There were a few downsides, and one of those was the pitiful range, which needed to be significantly upgraded.

The S-Pedelec that [Jacques] purchased is technically considered a moped, which means it needs to ride in traffic. The 500 watt-hour battery would only take him 45km (~28 miles) on a good day, which isn’t too bad but a problem if your battery runs down while in traffic, struggling to pedal a big heavy bicycle-like thing at car speed. You can swap batteries quickly, but carrying large unsecured extra batteries is a pain, and you need to stop to change them.

There were a few challenges to adding more batteries. The onboard BMS (battery management system) was incredibly picky with DRM and fussy about how many extra cells he could add. The solution that [Jacques] went with was to add an external balancer. This allowed him to add as many cells as he wanted while keeping the BMS happy. The battery geometry is a little wonky as he wanted to keep the pack within the frame. Putting it over the rear wheel would shift the center of gravity higher, changing the bike’s handling. After significant research and preparation, [Jacques] welded his custom battery back together with a spot welder. The final capacity came in at 2150wh (much better than the initial 500wh). An added benefit of the extra range is the higher speed, as the bike stays in the higher voltage domain for much longer. In eco mode, it can do 500km or 180km at full power.

It’s awe-inspiring, and we’re looking forward to seeing more e-bikes in the future. Maybe one day we’ll have tesla coil wireless e-bikes, but until then, we need to make do with battery packs.

DC UPS Keeps The Internet Up

November 1, 2021 by Al Williams 33 Comments

We occasionally get annoyed that so much gear takes the ubiquitous “wall wart” these days. But one advantage is that the devices operate on DC voltage. [TechRally] takes advantage of this to create an automatic DC UPS with dual outputs to power a router and modem in the event of a power outage. You can see two videos about the project below.

Some may say it would be better to use conventional UPS, but think about it. That UPS has a battery in it that gets converted to AC so the wall wart can convert it back to DC. Each conversion loses some energy, of course, and in the case of a cheap wall wart, you may even lose quite a bit.

The project contains eight 18650 batteries, an off-the-shelf charge controller, and power converters. Could you do a more efficient custom design? Maybe, but the use of these inexpensive and commonly available modules makes it quick and easy to pull something like this together.

No one would mistake this UPS for a commercial unit, but it does have a certain hacker aesthetic. We wouldn’t carry it through an airport, though. With those digital displays and all the wiring, it looks like a bad TV show’s bomb prop.

If you don’t care about the automatic switchover, we hear that 5V will power a lot of equipment these days and that makes battery operation as simple as stripping a USB cable. This could probably drive some other gear like a connected Raspberry Pi. Or, you could do that job with some supercaps.

Continue reading “DC UPS Keeps The Internet Up” →

Hackaday Links: September 26, 2021

September 26, 2021 by Dan Maloney 33 Comments

Dealing with breakdowns is certainly nothing new for drivers; plenty of us have had our ride die in mid-flight, and experienced the tense moment when it happens in traffic. But the highly integrated and instrumented nature of the newest generation of electric vehicles can bring an interesting twist to the roadside breakdown, if the after-action report of a Tesla driver is any indication.

While driving on a busy road at night, driver [Pooch] reports that his Tesla Model S started beeping and flashing warnings to get to the side of the road right away. [Pooch] tried to do so, but the car died, coasted to a stop in the middle of the road, and engaged the parking brakes. The bricked Tesla would have been a sitting duck in the middle of the road but for a DOT crew who happened to be nearby and offered to provide some protection while [Pooch] waited for help. The disturbing part was the inability to get the car into any of the service modes that might let it be pushed off to the shoulder rather than stuck in traffic, something that’s trivial to do in ICE vehicles, at least older ones.

In other electric vehicle news, Chevy Bolt owners are turning into the pariahs of the parking garage. General Motors is telling Bolt EV and EUV owners that due to the risk of a battery fire, they should park at least 50 feet (15 meters) away from other vehicles, and on the top level of any parking structures. There have been reports of twelve battery fires in Bolts in the US recently, which GM says may be due to a pair of manufacturing defects in the battery packs that sometimes occur together. GM is organizing a recall to replace the modules, but isn’t yet confident that the battery supplier won’t just be replicating the manufacturing problem. The social distancing rules that GM issued go along with some fairly stringent guidelines for charging the vehicle, including not charging overnight while parked indoors. With winter coming on in the northern hemisphere, that’s going to cause a bit of inconvenience and probably more than a few cases of non-compliance that could end in tragedy.

Fans of electronic music might want to check out “Sisters with Transistors”, a documentary film about some of the pioneering women of electronic music. Electronic music has been around a lot longer than most of us realize, and the film reaches back to the 1920s with Theremin virtuoso Clara Rockmore, and continues on into the 1980s with Laurie Spiegel, whose synthesizer work has been speeding away from Earth for the last 44 years on the Golden Records aboard the Voyager spacecraft. Hackaday readers will no doubt recognize some of the other women featured, like Daphne Oram and Delia Derbyshire, who cobbled together the early Dr. Who music with signal generators, tape loops, and random bits of electronics in the pre-synthesizer days of the early 60s. We’ve watched the trailer for the film and it looks pretty good — just the kind of documentary we like.

We’re big fans of circuit sculpture around here, and desperately wish we had the patience and the skill to make something like Mohit Bhoite or Jiri Praus can make. Luckily, there’s now a bit of a shortcut — Geeek Club’s Cyber Punk PCB Construction Kit. These kits are a little like the love child of Lego and PCBWay, with pieces etched and cut from PCB stock. You punch the pieces out, clean up the mouse bites, put Tab A into Slot B, and solder to make the connection permanent. Each kit has some components for the requisite blinkenlight features, which add to the cool designs. Looks like a fun way to get someone started on soldering, or to build your own skills.

And finally, another nail was driven into the coffin of Daylight Savings Time this week, as the island nation of Samoa announced they wouldn’t be “springing ahead” as scheduled this weekend. Daylight Savings Time has become a bone of contention around the world lately, and mounting research shows that the twice-yearly clock changes cause more trouble than they may be worth. In Europe, it’s due to be banned as soon as all the member nations can agree on normal time or summer time.

In the case of Samoa, DST was put into effect in 2010 on the assumption that it would give plantation workers more productive hours in the field and save energy. Instead, the government found that the time change just gave people an excuse to socialize more, which apparently upset them enough to change the rule. So there you have it — if you don’t like Daylight Savings Time, start partying it up.

Useless Machine Is A Clock

September 14, 2021 by Bryan Cockfield 15 Comments

Useless machines are a fun class of devices which typically turn themselves off once they are switched on, hence their name. Even though there’s no real point, they’re fun to build and to operate nonetheless. [Burke] has followed this idea in spirit by putting an old clock he had to use with his take on a useless machine of sorts. But instead of simply powering itself off when turned on, this useless machine dislodges itself from its wall mount and falls to the ground anytime anyone looks at it.

It’s difficult to tell if this clock was originally broken when he started this project, or if many rounds of checking the time have caused the clock to damage itself, but either way this project is an instant classic. Powered by a small battery driving a Raspberry Pi, the single-board computer runs OpenCV and is programmed to recognize any face pointed in its general direction. When it does, it activates a small servo which knocks it off of its wall, rendering it unarguably useless.

[Burke] doesn’t really know why he had this idea, but it’s goofy and fun. The duct tape that holds everything together is the ultimate finishing touch as well, and we can’t really justify spending too much on fit and finish for a project that tosses itself around one’s room. On the other hand, if you’re looking for a more refined useless machine, we have seen some that have an impressive level of intricacy.

Thanks to [alchemyx] for the tip!

Continue reading “Useless Machine Is A Clock” →

PS2 Gets The Ginger Portable Treatment

August 23, 2021 by Brian McEvoy 14 Comments

The first thing we notice about this portable PS2 is that the plastic looks like a consumer-grade shell, not a 3D printed case. It comes from [GingerOfOz], who has lots of portable conversions under his belt, so we are not surprised this looks like a genuine Sony device. When you are as experienced as he, details like plastic texture, and button selection, are solved problems, but shouldn’t be taken for granted by us mortals.

Of course, this isn’t just pretty, and if it weren’t functional, we wouldn’t be talking about it. The system plays nearly all PS2 titles from USB memory. The notable exceptions are the ones that refuse to load without a Dualshock controller. Rude. If you’re wondering if it plays games at full speed, yes. It achieves authentic speed because it uses a PS2 slim motherboard which gets cut down by a Dremel. Custom PCBs provide the rest of the hardware, like volume buttons and battery charging. There is no optical drive since they are power hogs, so your cinematic cut scenes may lag, and load times are a little longer.

Modern mobile phones are one of the most powerful gaming systems ever built, but there is something about purpose-built portable gaming hardware that just feels right. You know?

Continue reading “PS2 Gets The Ginger Portable Treatment” →

Tesla’s Megapack Battery Burned For Days In Grid Storage Fire

August 12, 2021 by Lewin Day 174 Comments

Lithium rechargeable batteries have been heralded for their high-density energy storage, enabling all manner of technologies to come to fruition. From drones to practical electric cars to large-scale grid storage, the applications are endless.

The fire as seen from a drone overhead. Source: Twitter/@FireRescueVic

However, the lithium rechargeable battery has always had one major flaw–flammability. Pushed outside their operating range or otherwise tipped into thermal runaway, and they can burn ferociously as a result.

This came to pass in late July, at the Victorian Big Battery in Geelong, Australia, and it took significant effort to extinguish the blaze. Let’s take a look at the project and see how this came to occur.

Grid-Scale Storage

The Victorian Big Battery is a grid storage project similar in construction to the Hornsdale Power Reserve in neighboring South Australia. However, where the Hornsdale facility fields 194 MWh of capacity and 150MW peak power delivery, the new project aims to go much further. The Victorian project aims to install 450 MWh of capacity and deliver a peak power output of 300 MW.

Continue reading “Tesla’s Megapack Battery Burned For Days In Grid Storage Fire” →