# CORDIC Brings Math To FPGA Designs

We are always excited when we see [Hamster] post an FPGA project, because it is usually something good. His latest post doesn’t disappoint and shows how he uses the CORDIC algorithm to generate very precise sine and cosine waves in VHDL. CORDIC (Coordinate Rotation Digital Computer; sometimes known as Volder’s algorithm) is a standard way to compute hyperbolic and trigonometric functions. What’s nice is that the algorithm only requires addition, subtraction, bit shifts, and a lookup table with an entry for each bit of precision you want. Of course, if you have addition and negative numbers, you already have subtraction. This is perfect for simple CPUs and FPGAs.

[Hamster] not only has the VHDL code but also provides a C version if you find that easier to read. In either case, the angle is scaled so that 360 degrees is a full 24-bit word to allow the most precision. Although it is common to compute the result in a loop, with the FPGA, you can do all the math in parallel and generate a new sample on each clock cycle.

# Unmanned Sailboat Traverses The North Atlantic

Sailboats have been traversing the Atlantic Ocean since before 1592, sailing through sunshine, wind, and rain. The one thing that they’ve all had in common has been a captain to pilot the ship across this vast watery expanse, at least until now. A company called Offshore Sensing has sailed an unmanned vessel all the way from Canada to Ireland.

The ship, called the Sailbuoy, attempted the journey last year as well but only made it about halfway before the mission was abandoned. This year, however, the voyage was finally completed, and this craft is officially the first unmanned ship to cross the Atlantic Ocean. The journey took about 80 days using sails and a small set of solar panels to drive the control electronics.

Using this technology, the company can investigate wave activity in specific areas of the ocean without having to send out a manned vessel to install a permanent buoy. The sailbuoy simply uses its autonomy to stay in a particular patch of ocean. There have been other missions that the sailbuoy has been tasked with as well, such as investigating the aftermath of the Deepwater Horizon oil spill in the Gulf of Mexico. With a reliable craft like this, it becomes much easier, safer, and less expensive to explore the ocean’s surface.

Thanks to [Andy] for the tip!

# Create Your Own ESP8266 Shields

The ESP8266 has become incredibly popular in a relatively short time, and it’s no wonder. Cheap as dirt, impressively powerful, Arduino-compatible, and best of all, includes Wi-Fi right out of the box. But for all its capability and popularity, it’s still lagging behind the Arduino in at least one respect. Namely, the vast collection of add-on “Shields” which plug into the Arduino to add everything from breadboards to GPS receivers.

Until such time as the free market decides to pick up the pace and start making standardized shields for the various ESP8266 development boards, it looks as if hackers are going to have to pick up the slack. [Rui Santos] has put together a very detailed step-by-step guide on the creation of a simple shield for the popular Wemos D1 Mini board, which should give you plenty of inspiration for spinning up your own custom add-on modules.

Presented as a written tutorial as well as a two part video, this guide covers everything from developing and testing your circuit on a breadboard to designing your PCB in KiCad and sending it off for fabrication. The end result is a professional looking PCB that matches the footprint of the stock D1 Mini and adds a DS18B20 temperature sensor, PIR motion detector, photoresistor, and some screw down terminals.

[Rui] goes on to show how you can utilize the new sensors shield via a web interface hosted on the ESP8266, and even wraps the whole thing up in a 3D printed enclosure. All worthwhile skills to check out if you’re looking to produce more cohesive finished products.

If you’re looking for a similar project for the ESP32, [Rui] has you covered there as well. You may also be interested in the series of ESP8266 tutorials we recently highlighted.

# Scooter Hauls Kids With A Little Heavy Metal

Where there’s a will, there’s a way. Similarly, where there’s a paying customer and a well stocked metalworking shop, there will also be a way. That’s about all the backstory you need to understand this latest creation from [Richard Day] of 42Fab. A customer asked him to build something that didn’t exist, and in a few hours he not only fabricated it from scratch but documented the whole thing for our viewing pleasure.

The object in question is a mount that would allow the customer to pull a “Burley Bee” kid trailer behind their electric scooter. The trailer is only meant for a bicycle, but the expected stresses of getting pulled around by a scooter seemed similar enough that [Richard] figured it should work. Especially since the ride height of the scooter lined up almost perfectly with the trailer’s tongue. The trick is, he wanted to avoid making permanent changes to either the scooter or the trailer.

On the scooter side, [Richard] came up with a clamp arrangement that would squeeze onto the frame. This gave him plenty of strength, without having to put any holes in the scooter. To create the clamp he took two pieces of 1/4″ x 2″ steel flat bar and welded 5/16″ nuts to them. By drilling the threads out of outer nuts they act as bushings, so cranking down on the bolts draws the two pieces together. To simplify the alignment, he welded the nuts to the bars while the bolts were threaded in, so he knew everything would be in place.

For the trailer side, he took another piece of flat steel and turned it into a “U” shape by cutting almost all the way through the back of it and then folding it over in his vice. A bead of metal was then laid in the cut with the welder to strengthen it back up. [Richard] used this opportunity to demonstrate the difference between pushing and pulling the torch while welding, which is an interesting tip to file away. A hole drilled through the two sides and a little grinding, and it’s ready to mount.

Between the two fabricated components is some flat stock welded at an eyed up angle. As [Richard] says in the video, the nice thing about these one-off projects is that you can basically design on the fly. Plus you can always use a hammer to make some final adjustments.

While his isn’t the first bike trailer hack we’ve seen here at Hackaday, it would be fair to say it’s something of a rarity around these parts. Usually we get word of somewhat larger bits of kit getting dragged around.

# Moving 3D Printed Prosthetic Arms With A Pulse

One of the best uses of 3D printers we’ve seen are custom prosthetics. Even today, custom-built prosthetics cost an arm and a leg, but there’s no reason why they should. Right now, we can scan someone’s arm or leg, import that scan into a 3D-modeling program, and design a custom-fit orthotic that can be spit out on a 3D printer. Now, we’re seeing some interesting methods of turning those 3D-printed parts into the beginnings of a cybernetic design. This is a custom printed robotic hand controlled by a pulse sensor. It’s in its early stages right now, but so far the results are promising and this is a great entry to The Hackaday Prize

This project draws upon a few of the team’s other endeavours. The first is a 3D-printed mini linear actuator, a project that made it into the finals of the Hackaday Prize in the Robotics Module challenge. This tiny linear actuator is actually powered by a tiny hobby servo rigged up for continuous rotation. Add in some 3D printed gears and a well-designed frame, and you have something that’s just as good as fantastically expensive linear actuators as a bargain basement price. This pulse sensor arm also makes use of the team’s TNS 1i, a 3D printed robotic hand that makes use of those tiny little linear actuators.

Of course, if you’re going to build a prosthetic robotic arm, you have to have some sort of brain-machine interface. Previously, the team was using Myoware muscle sensors to control the opening and closing of the fingers. This changed, however, when [Giovanni] was trying to get his Samsung gear S3 to detect his pulse. Apparently, moving your wrist when trying to get a smartwatch to listen in on your heartbeat is an acceptable substitute for a muscle sensor.

# FOSSCON 2018: Where Open Source And LEGO Collide

It probably won’t come as a surprise to anyone reading this, but hackers and makers absolutely love LEGO. We think you’d be hard pressed to find a Hackaday reader, young or old, that hasn’t spent some quality time with the little plastic bricks from Billund, Denmark. So it follows that there’s a considerable community of individuals who leverage their better than average technical prowess to utilize LEGO in new and unique ways. But the activities and history of these LEGO hackers is not exactly common knowledge to those who aren’t heavily vested in the hobby.

During the recent FOSSCON 2018 in Philadelphia, Daniel Pikora gave attendees a comprehensive look at the intersection of open source development and the world’s most popular brand of construction toys. A software developer with a penchant for open source code by trade, he’s also an avid member of what’s known as the Adult Fan of LEGO (AFOL) community who’s exhibited his creations at shows across the United States and Canada. Such a unique perspective, with a foot in both the FOSS and LEGO camps, makes Daniel an ideal tour guide for this particular microcosm of toys and tech.

In a whirlwind presentation that took attendees through 49 slides in about as many minutes, Daniel covered LEGO’s beginnings in the 1930s to the rise of 3D printed custom bricks, and everything in between. Some of the engineering-centric product lines, such as Technic and Mindstorms, were already fairly well known to the types of folk who spent a beautiful Saturday in Philadelphia at an open source conference. But Daniel’s deep-dive into the long history of open source LEGO projects brought to light the work of so many dedicated developers that everyone walked away with a newfound respect for the amount of work the AFOL community has put into elevating LEGO from a child’s toy to a legitimate tool. Join me below for a look at the particulars of that deep dive.

You wake up in the morning, and check Hackaday over breakfast. Then it’s off to work or school, where you’ve already had to explain the Jolly Wrencher to your shoulder-surfing colleagues. And then to a hackspace or back to your home lab, stopping by the skull-and-cross-wrenches while commuting, naturally. You don’t bleed red, but rather #F3BF10. It’s time we talked.

The Hackaday writing crew goes to great lengths to cover all that is interesting to engineers and enthusiasts. We find ourselves stretched a bit thin and it’s time to ask for help. Want to lend a hand while making some extra dough to plow back into your projects? We’re looking for contributors to write a few blog posts per week and keep the Hackaday flame burning.

Contributors are hired as private contractors and paid for each article. You should have the technical expertise to understand the projects you write about, and a passion for the wide range of topics we feature. You’ll have access to the Hackaday Tips Line, and we count on your judgement to help us find the juicy nuggets that you’d want to share with your hacker friends.

If you’re interested, please email our jobs line and include:

• One example post written in the voice of Hackaday. Include a banner image, at least 150 words, the link to the project, and any in-links to related and relevant Hackaday features. We need to know that you can write.
• Details about your background (education, employment, interests) that make you a valuable addition to the team. What do you like, and what do you do?
• Links to your blog/project posts/etc. that have been published on the Internet, if any.