Can You Store Renewable Energy In A Big Pile Of Gravel?

As the world grapples with transitioning away from fossil fuels, engineers are hard at work to integrate new types of generation into the power grid. There’s plenty of challenges, particularly around the intermittent nature of many renewable energy sources. Energy storage projects are key to keeping the lights on round the clock, even when the wind isn’t blowing and the sun isn’t shining.

Conventional grid-level energy storage has long made use of pumped hydro installations where water is pumped uphill to a storage reservoir where it can later be used to run a generator. More recently, batteries are being used to do the job. When you consider the cost of these installations and their storage capacities, there is a gap between batteries and pumped hydro. A recently published whitepaper proposes Mountain Gravity Energy Storage — gravity-based energy storage using sand or gravel in mountainous areas — is the technology that can bridge the gap.

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The Young Engineers Guide To University Capstone Projects

Engineering degrees are as wide and varied as the potential careers on offer out in the real world. There’s plenty of maths to learn, and a cavalcade of tough topics, from thermodynamics to fluid mechanics. However, the real challenge is the capstone project. Generally taking place in the senior year of a four-year degree, it’s a chance for students to apply everything they’ve learned on a real-world engineering project.

Known for endless late nights and the gruelling effort required, it’s an challenge that is revered beforehand, and boasted about after the fact. During the project, everyone is usually far too busy to talk about it. My experience was very much along these lines, when I undertook the Submarine That Can Fly project back in 2012.  The project taught me a lot about engineering, in a way that solving problems out of textbooks never could. What follows are some of the lessons I picked up along the way. Continue reading “The Young Engineers Guide To University Capstone Projects”

Jubilee: A Toolchanging Homage To 3D Printer Hackers Everywhere

I admit that I’m late to the 3D printing game. While I just picked up my first printer in 2018, the rest of us have been oozing out beautiful prints for over a decade. And in that time we’ve seen many people reimagine the hardware for mischief besides just printing plastic. That decade of hacks got me thinking: what if the killer-app of 3D printing isn’t the printing? What if it’s programmable motion? With that, I wondered: what if we had a machine that just offered us motion capabilities? What if extending those motion capabilities was a first class feature? What if we had a machine that was meant to be hacked?

One year later, I am thrilled to release an open-source multitool motion platform I call Jubilee. For a world that’s hungry for toolchanging 3D printers, Jubilee might be the best toolchanging 3D printer you can build yourself–with nothing more than a set of hand tools and some patience. But it doesn’t stop there. With a standardized tool pattern established by E3D and a kinematically coupled hot-swappable bed, Jubilee is rigged to be extended by anyone looking to harness its programmable motion capabilities for some ad hoc automation.

Jubilee is my homage to you, the 3D printer hacker; but it’s meant to serve the open-source community at large. Around the world, scientists, artists, and hackers alike use the precision of automated machines for their own personal exploration and expression. But the tools we use now are either expensive or cumbersome–often coupled with a hefty learning curve but no up-front promise that they’ll meet our needs. To that end, Jubilee is meant to shortcut the knowledge needed to get things moving, literally. Jubilee wants to be an API for motion.

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Lessons In Li-Ion Safety

If you came here from an internet search because your battery just blew up and you don’t know how to put out the fire, then use a regular fire extinguisher if it’s plugged in to an outlet, or a fire extinguisher or water if it is not plugged in. Get out if there is a lot of smoke. For everyone else, keep reading.

I recently developed a product that used three 18650 cells. This battery pack had its own overvoltage, undervoltage, and overcurrent protection circuitry. On top of that my design incorporated a PTC fuse, and on top of that I had a current sensing circuit monitored by the microcontroller that controlled the board. When it comes to Li-Ion batteries, you don’t want to mess around. They pack a lot of energy, and if something goes wrong, they can experience thermal runaway, which is another word for blowing up and spreading fire and toxic gasses all over. So how do you take care of them, and what do you do when things go poorly?

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RISC-V: Why The ISA Battles Aren’t Over Yet

A computer processor uses a so-called Instruction Set Architecture to talk with the world outside of its own circuitry. This ISA consists of a number of instructions, which essentially define the functionality of that processor, which explains why so many ISAs still exist today. It’s hard to find that one ISA that works for as many distinct use cases as possible, after all.

A fairly new ISA is RISC-V, the first version of which was created back in 2010 at the University of California, Berkeley. Intended to be a fully open ISA, targeting both students (as a learning tool) and industrial users, it is claimed to incorporate a number of design choices that should make it more attractive for a number of applications.

In this article I’ll take a look behind the marketing to take stock of how exactly RISC-V differs from other open ISAs, including Power, SPARC and MIPS.

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5G Is For Robots

Ecclesiastes 1:9 reads “What has been will be again, what has done will be done again; there is nothing new under the sun.” Or in other words, 5G is mostly marketing nonsense; like 4G, 3G, and 2G was before it. Let’s not forget LTE, 4G LTE, Advance 4G, and Edge.

Just a normal everyday antenna array in a Seattle parking garage.

Technically, 5G means that providers could, if they wanted to, install some EHF antennas; the same kind we’ve been using forever to do point to point microwave internet in cities. These frequencies are too lazy to pass through a wall, so we’d have to install these antennas in a grid at ground level. The promised result is that we’ll all get slightly lower latency tiered internet connections that won’t live up to the hype at all. From a customer perspective, about the only thing it will do is let us hit the 8Gb ceiling twice as faster on our “unlimited” plans before they throttle us. It might be nice on a laptop, but it would be a historically ridiculous assumption that Verizon is going to let us tether devices to their shiny new network without charging us a million Yen for the privilege.

So, what’s the deal? From a practical standpoint we’ve already maxed out what a phone needs. For example, here’s a dirty secret of the phone world: you can’t tell the difference between 1080p and 720p video on a tiny screen. I know of more than one company where the 1080p on their app really means 640 or 720 displayed on the device and 1080p is recorded on the cloud somewhere for download. Not a single user has noticed or complained. Oh, maybe if you’re looking hard you can feel that one picture is sharper than the other, but past that what are you doing? Likewise, what’s the point of 60fps 8k video on a phone? Or even a laptop for that matter?

Are we really going to max out a mobile webpage? Since our device’s ability to present information exceeds our ability to process it, is there a theoretical maximum to the size of an app? Even if we had Gbit internet to every phone in the world, from a user standpoint it would be a marginal improvement at best. Unless you’re a professional mobile game player (is that a thing yet?) latency is meaningless to you. The buffer buffs the experience until it shines.

So why should we care about billion dollar corporations racing to have the best network for sending low resolution advertising gifs to our disctracto cubes? Because 5G is for robots.

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Hacking Mars: InSight Mole Is On The Move Again

Your job might be tough, but spare a thought for any of the engineers involved in the Mars InSight lander mission when they learned that one of the flagship instruments aboard the lander, indeed the very instrument for which the entire mission was named, appeared to be a dud. That’s a bad day at work by anyone’s standards, and it happened over the summer when it was reported that the Mars Interior Exploration using Seismic Investigations, Geodesy and Heat Transport lander’s Heat Flow and Physical Properties Package (HP³), commonly known as “The Mole”, was not drilling itself into the Martian regolith as planned.

But now, after months of brainstorming and painstaking testing on Earth and on Mars, it looks as if the mole is working again. NASA has announced that, with a little help from the lander’s backhoe bucket, the HP³ penetrator has dug itself 2 cm into the soil. It’s a far cry from the 5-meter planned depth for its heat-transfer experiments, but it’s progress, and the clever hack that got the probe that far might just go on to salvage a huge chunk of the science planned for the $828 million program.

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