AGES Of Renewable Energy Storage

March 3, 2023 by Navarre Bartz 26 Comments

As society transitions toward renewable energy sources, energy storage inevitably comes to mind. Researchers at the University of Illinois at Urbana-Champaign have found one way to store renewable energy that re-purposes existing fossil fuel infrastructure.

While geothermal electricity generation shows a lot of promise, it’s currently limited to a select few areas where hot rock is close to the Earth’s surface. Advanced Geothermal Energy Storage (AGES) stores energy underground as heat and recovers it later, even in places without high subsurface temperatures. For this study, the researchers located an old oil well and instrumented it with “flow meters, fiber optic
distributed temperature sensing (DTS) cable, surface pressure and temperature gauges, and downhole pressure and temperature gauges to monitor the thermal and hydraulic changes during the injection test.”

This field study found that AGES system efficiency could be as high as 82% and yield an “economically viable” levelized cost of electricity (LCOE) of $0.138/kWh. Using existing deep hole infrastructure speeds up site selection and deployment of AGES when compared to developing on an undisturbed location, making this a very interesting way to deploy grid-scale storage rapidly.

We’ve covered reusing fossil fuel infrastructure before as well as challenges and unusual solutions to the energy transition if you’re looking for more about what might be on a future smart grid.

A line art schematic of a bicycle CVT drive. Two large green circles at the bottom have the text "1. Increases speed" where the crank arm would enter the system. A series of cam arms highlighted in red say "2. Converts from rotary to reciprocating motion." Finally, a blue highlighted bearing says "3. Converts from reciprocating back to rotary motion."

A Look Inside Bicycle Gearboxes

March 2, 2023 by Navarre Bartz 23 Comments

While bicycle gearboxes date back to at least the 1920s, they’re relatively unseen in bike racing. One exception is Honda’s race-winning mid-drive gearboxes, and [Alee Denham] gives us a look at what makes these unique drives tick.

Honda has developed three generations of bicycle gearbox as part of their company’s R&D efforts, but none have ever been released as a commercial product. Designed as a way for their engineers to stretch their mental muscles, the gearboxes were only used in bike races and seen at a few trade shows. In 2004, the third gen “derailleur in a box” led to the first gearbox victory in the Downhill World Cup Circuit.

The third gen gearbox differs significantly from the CVT drivetrains in the first and second generation gearboxes, but it is unclear why Honda abandoned the CVT. [Denham] has a nice animation detailing the inner workings of these CVTs based on information from the original patents for these rarely seen gearboxes.

Derailleurs remain the primary drivetrain in racing due to their lighter weight and higher overall efficiency. While still expensive, the decreased maintenance of gearbox drivetrains make a lot of sense for more mundane cycling tasks like commuting or hauling cargo, but only time will tell if the derailleur can be supplanted on the track and trail.

For more on bicycle drivetrains, check out this chainless digital drivetrain or the pros and cons of e-bike conversions.

Continue reading “A Look Inside Bicycle Gearboxes” →

A grey car sits in the background out of focus, its front facing the camera. It sits over an asphalt roadway with a metal rail extending from the foreground to behind the car in the distance. The rail has a two parallel slots and screws surrounding the slots running down the rail.

What Happened To Sweden’s Slot Car EV Road?

March 1, 2023 by Navarre Bartz 60 Comments

Many EVs can charge 80% of their battery in a matter of minutes, but for some applications range anxiety and charge time are still a concern. One possible solution is an embedded electrical rail in the road like the [eRoadArlanda] that Sweden unveiled in 2016.

Overhead electrical wires like those used in trolleys have been around since the 1800s, and there have been some tests with inductive coils in the roadway, but the 2 km [eRoadArlanda] takes the concept of the slot car to the next level. The top of the rail is grounded while the live conductor is kept well underground beneath the two parallel slots. Power is only delivered when a vehicle passes over the rail with a retractable contactor, reducing danger for pedestrians, animals, and other vehicles.

One of the big advantages of this technology being in the road bed is that both passenger and commercial vehicles could use it unlike an overhead wire system that would require some seriously tall pantographs for your family car. Testing over several Swedish winters shows that the system can shed snow and ice as well as rain and other road debris.

Unfortunately, the project’s website has gone dark, and the project manager didn’t respond when we reached out for comment. If there are any readers in Sweden with an update, let us know in the comments!

We’ve covered both overhead wire and embedded inductive coil power systems here before if you’re interested in EV driving with (virtually) unlimited range.

Continue reading “What Happened To Sweden’s Slot Car EV Road?” →

A man sits in front of a wooden table. There is a black box with a number of knobs hand-labeled on blue painter's tape. A white breadboard with a number of wires protruding from it is visible on the box's left side. An oscilliscope is behind the black box and has a yellow waveform displaying on its screen.

A More Expressive Synth Via Flexure

February 28, 2023 by Navarre Bartz 13 Comments

Synthesizers can make some great music, but sometimes they feel a bit robotic in comparison to their analog counterparts. [Sound Werkshop] built a “minimum viable” expressive synth to overcome this challenge. (YouTube)

Dubbed “The Wiggler,” [Sound Werkshop]’s expressive synth centers on the idea of using a flexure as a means to control vibrato and volume. Side-to-side and vertical movement of the flexure is detected with a pair of linear hall effect sensors that feed into the Daisy Seed microcontroller to modify the patch.

The build itself is a large 3D printed base with room for the flexure and a couple of breadboards for prototyping the circuits. The keys are capacitive touch pads, and everything is currently held in place with hot glue. [Sound Werkshop] goes into detail in the video (below the break) on what the various knobs and switches do with an emphasis on how it was designed for ease of use.

If you want to learn more about flexures, be sure to checkout this Open Source Flexure Construction Kit.

Continue reading “A More Expressive Synth Via Flexure” →

A series of five cymbals sitting on white and black speckled carpet in front of a green loveseat. Each cymbal is assembled from four printed sections. Their colors from left to right are yellow and grey, red and black, black, teal and black, and white and black. A sixth, grey and black cymbal is sitting in the middle of the loveseat cushion.

Challenging The Limits Of 3D Printing With Cymbals

February 28, 2023 by Navarre Bartz 22 Comments

We’re big believers in 3D printing here at Hackaday, but it’s important to recognize that there are plenty of applications where additive manufacturing (at least, from a desktop machine) just isn’t suitable. But that doesn’t mean we don’t want to see what happens if you try. For example, [The Drum Thing] wanted to test the limits of 3D printing by printing a set of cymbals.

[The Drum Thing] had a friend design a cymbal in CAD and then the printed quarters were glued together. In the name of science, they produced them in six different materials to compare performance. Each cymbal was played for a short period or until it failed, including some very interesting slow motion camera work showing the vibrations traveling through the cymbals.

As one might expect, bashing “wafer thin” pieces of printed plastic with a wooden drumstick didn’t work out well for most of the cymbals, although the TPU, carbon fiber, and nylon cymbals were did largely survive their time in the limelight. The other cymbals all failed, either shattering, cracking, or failing at the glue joints. Based on the video, it seems the same glue was used for all of the cymbals, so making sure to have a better match between material and adhesive could help with the glue failures.

Maybe future testing can involve playing these cymbals with a quadrotor?

Continue reading “Challenging The Limits Of 3D Printing With Cymbals” →

A person holds a bundle of white, black, and blue wires. The left hand side of the wires are wrapped with black tape. The wires are inside a wire wrapping machine with a grey plastic "C" which rotates inside seven small pulleys. A large pulley in the background drives three of the pulleys to rotate the "C" around and wrap the wires with tape from the spool attached to the "C."

DIY Tool Makes Wrapping Wiring Harnesses A Breeze

February 26, 2023 by Navarre Bartz 17 Comments

If you’re making a lot of wiring harnesses, wrapping them can become a bit of a drag. [Well Done Tips] wanted to make this process easier and built a wiring harness wrapping machine.

The “C” shape of this wrapping machine means that you can wrap wires that are still attached at one or both ends, as you don’t have to pull the wires all the way through the machine. The plastic “C” rotates inside a series of pulleys with three of them driven by a belt attached to an electric motor. A foot pedal actuates the motor and speed is controlled by a rotary dial on the motor controller board.

Since this is battery powered, you could wrap wires virtually anywhere without needing to be near a wall outlet. This little machine seems like it would be really great if you need to wrap a ton of wire and shouldn’t be too complicated to build. Those are some of our favorite hacks.

If you’re wanting more wire harness fun, try this simple online wiring harness tool or see how the automotive industry handles harnesses.

Continue reading “DIY Tool Makes Wrapping Wiring Harnesses A Breeze” →

A dark grey couch with a white pegboard on a drawer slide protruding from its arm. The pegboard has a magazine holder, pen holder, and several other miscellaneous bins holding odds and ends on it.

Sofa Armrest Is A Nifty Storage Spot

February 26, 2023 by Navarre Bartz 7 Comments

If you’re like us, you’re always in need of a little more space to store things. [Javier Guerrero] realized his sofa wasn’t living up to its full storage potential and designed this sofa armrest storage.

[Guerrero]’s sofa arms were hiding 80 liters of space, so he really wanted to do something with it. After disassembling them, he found his original plan of just cutting them up wouldn’t work due to the minimal structure inside. Not to be discouraged, he drew up some plans and built replicas from 15 mm plywood.

For one armrest, he made a single giant box that opens from the top where he can store a couple of folding chairs. On the other side, he made a shorter top-opening bin for charging phones and storing the remote. Underneath that is a large pull out drawer with a pegboard for organizational bliss.

The arms were upholstered using the fabric from the original arms plus a little extra from another slip cover. Separate arm modules and easily obtainable matching fabric aren’t a given for every couch, but we expect that almost any sofa with arms could benefit from this hack given a little ingenuity.

If you’re looking for more storage hacks, checkout this Modular Storage from Old Filament Spools, the Last Component Storage System You’d Ever Need, or the ever popular Gridfinity.