Electric Motors Run Continuously At Near-Peak Power

November 26, 2024 by Bryan Cockfield 26 Comments

For a lot of electrical and mechanical machines, there are nominal and peak ratings for energy output or input. If you’re in marketing or advertising, you’ll typically look at the peak rating and move on with your day. But engineers need to know that most things can only operate long term at a fraction of this peak rating, whether it’s a power supply in a computer, a controller on an ebike, or the converter on a wind turbine. But this electric motor system has a unique cooling setup allowing it to function at nearly full peak rating for an unlimited amount of time.

The motor, called the Super Continuous Torque motor built by German automotive manufacturer Mahle is capable of 92% of its peak output power thanks to a unique oil cooling system which is able to remove heat and a rapid rate. Heat is the major limiter for machines like this; typically when operating at a peak rating a motor would need to reduce power output to cool down so that major components don’t start melting or otherwise failing. Given that the largest of these motors have output power ratings of around 700 horsepower, that’s quite an impressive benchmark.

The motor is meant for use in passenger vehicles but also tractor-trailer style trucks, where a motor able to operate at its peak rating would mean a smaller size motor or less weight or both, making them easier to fit into the space available as well as being more economically viable. Mahle is reporting that these motors are ready for production so we should be seeing them help ease the transportation industry into electrification. If you’re more concerned about range than output power, though, there’s a solution there as well so you don’t have to be stuck behind the times with fossil fuels forever.

Thanks to [john] for the tip!

3D Printed Boat Uses Tank Tracks For Amphibious Propulsion

November 23, 2024 by Lewin Day 15 Comments

Boats normally get around with propellers or water jets for propulsion. Occasionally, they use paddles. [Engineering After Hours] claims he is “changing the boat game forever” with his new 3D printed boat design that uses a tank tread for propulsion instead. Forgive him for the hyperbole of the YouTuber. It’s basically a modified paddle design, but it’s also pretty cool.

It works on land, even if it doesn’t steer well!

The basic idea is simple enough—think “floating snowmobile” and you’re in the ballpark. In the water, the chunky tank track provides forward propulsion with its paddle-like treads. It’s not that much different from a paddle wheel steamer. However, where it diverges is that it’s more flexible than a traditional paddle wheel.

The tracked design is actually pretty good at propelling the boat in shallow water without getting stuck. In fact, it works pretty well on dirt, too! The video covers the basic concept, but it also goes into some detail regarding optimizing the design, too. Getting the float and track geometry right is key to performance, after all.

If you’re looking to build an oddball amphibious craft, maybe working with the snowmobile concept is worth your engineering time. Continue reading “3D Printed Boat Uses Tank Tracks For Amphibious Propulsion” →

Transforming Drone Drives And Flies

November 22, 2024 by Danie Conradie 8 Comments

Vehicles that change their shape and form to adapt to their operating environment have long captured the imagination of tech enthusiasts, and building one remains a perennial project dream for many makers. Now, [Michael Rechtin] has made the dream a bit more accessible with a 3D printed quadcopter that seamlessly transforms into a tracked ground vehicle.

The design tackles a critical engineering challenge: most multi-mode vehicles struggle with the vastly different rotational speeds required for flying and driving. [Michael]’s solution involves using printed prop guards as wheels, paired with lightweight tracks. An extra pair of low-speed brushless motors are mounted between each wheel pair, driving the system via sprockets that engage directly with the same teeth that drive the tracks.

The transition magic happens through a four-bar linkage mounted in a parallelogram configuration, with a linear actuator serving as the bottom bar. To change from flying to driving configuration the linear actuator retracts, rotating the wheels/prop guards to a vertical position. A servo then rotates the top bar, lifting the body off the ground. While this approach adds some weight — an inevitable compromise in multi-purpose machines — it makes for a practical solution.

Powering this transformer is a Teensy 4.0 flight controller running dRehmFlight, a hackable flight stabilization package we’ve seen successfully adapted for everything from VTOLs to actively stabilized hydrofoils. Continue reading “Transforming Drone Drives And Flies” →

A Vintage Radiator Core, From Scratch

November 13, 2024 by Jenny List 25 Comments

There are sadly few 1914 Dennis fire engines still on the road, so when the one owned by Imperial College in London needs a spare part, it can not be ordered from the motor factors and must be made from scratch. Happily, [Andy Pugh] is an alumnus with the required metalworking skills, so in the video below we see him tackling the manufacture of flattened brass tubes for its radiator core.

Forming a round tube to a particular shape is done by pulling it through a die whose profile gradually changes from round to the desired shape. We see him make a couple of tries at this, finally succeeding with one carefully designed to have a constant circumference. The use of CNC machining is something that wouldn’t have been available in the Dennis works in the early 20th century, so we can marvel at the skills of the machinists back then who made the original. Here in 2024 he makes a drawing rig with a geared chain drive suitable for larger scale production.

The video is both a fascinating look at tube drawing and a mind-cleansing piece of workshop observation, and we have to say we enjoyed watching it. If [Andy]’s name sounds familiar to you, this might be because this isn’t the first go he’s had at manufacturing vehicle parts.

Continue reading “A Vintage Radiator Core, From Scratch” →

All Aboard The Good Ship Benchy

November 9, 2024 by Jenny List 26 Comments

We’ll go out on a limb here and say that a large portion of Hackaday readers are also boat-builders. That’s a bold statement, but as the term applies to anyone who has built a boat, we’d argue that it encompasses anyone who’s run off a Benchy, the popular 3D printer test model. Among all you newfound mariners, certainly a significant number must have looked at their Benchy and wondered what a full-sized one would be like. Those daydreams of being captain of your ship may not have been realized, but [Dr. D-Flo] has made them a reality for himself with what he claims is the world’s largest Benchy. It floats, and carries him down the waterways of Tennessee in style!

The video below is long but has all the details. The three sections of the boat were printed in PETG on a printer with a one cubic meter build volume, and a few liberties had to be taken with the design to ensure it can be used as a real boat. The infill gaps are filled with expanding foam to provide extra buoyancy, and an aluminium plate is attached to the bottom for strength. The keel meanwhile is a 3D printed sectional mold filled with concrete. The cabin is printed in PETG again, and with the addition of controls and a solar powered trolling motor, the vessel is ready to go. Let’s face it, we all want a try!

Continue reading “All Aboard The Good Ship Benchy” →

Disposable Vape Batteries Power EBike

November 7, 2024 by Bryan Cockfield 15 Comments

There are a lot of things that get landfilled that have some marginal value, but generally if there’s not a huge amount of money to be made recycling things they won’t get recycled. It might not be surprising to most that this is true of almost all plastic, a substantial portion of glass, and even a lot of paper and metals, but what might come as a shock is that plenty of rechargeable lithium batteries are included in this list as well. It’s cheaper to build lithium batteries into one-time-use items like disposable vape pens and just throw them out after one (or less than one) charge cycle, but if you have some spare time these batteries are plenty useful.

[Chris Doel] found over a hundred disposable vape pens after a local music festival and collected them all to build into a battery powerful enough for an ebike. Granted, this involves a lot of work disassembling each vape which is full of some fairly toxic compounds and which also generally tend to have some sensitive electronics, but once each pen was disassembled the real work of building a battery gets going. He starts with testing each cell and charging them to the same voltage, grouping cells with similar internal resistances. From there he assembles them into a 48V pack with a battery management system and custom 3D printed cell holders to accommodate the wide range of cell sizes. A 3D printed enclosure with charge/discharge ports, a power switch, and a status display round out the build.

With the battery bank completed he straps it to his existing ebike and hits the trails, easily traveling 20 miles with barely any pedal input. These cells are only rated for 300 charge-discharge cycles which is on par for plenty of similar 18650 cells, making this an impressive build for essentially free materials minus the costs of filament, a few parts, and the sweat equity that went into sourcing the cells. If you want to take an ebike to the next level of low-cost, we’d recommend pairing this battery with the drivetrain from the Spin Cycle.\

Thanks to [Anton] for the tip!

Continue reading “Disposable Vape Batteries Power EBike” →

An Electric Vehicle Conversion With A Difference

October 30, 2024 by Jenny List 25 Comments

For a first try at an electric vehicle conversion we’re guessing that most would pick a small city car as a base vehicle, or perhaps a Kei van. Not [LiamTronix], who instead chose to do it with an old Ferguson tractor. It might not be the most promising of EV platforms, but as you can see in the video below, it results in a surprisingly practical agricultural vehicle.

A 1950s or 1960s tractor like the Ferguson usually has its engine as a structural member with the bellhousing taking the full strength of the machine and the front axle attached to the front of the block. Thus after he’s extracted the machine from its barn we see him parting engine and gearbox with plenty of support, as it’s a surprisingly hazardous process. These conversions rely upon making a precise plate to mount the motor perfectly in line with the input shaft. We see this process, plus that of making the splined coupler using the center of the old clutch plate. It’s been a while since we last did a clutch alignment, and seeing him using a 3D printed alignment tool we wish we’d had our printer back then.

The motor is surprisingly a DC unit, which he first tests with a 12 V car battery. We see the building of a hefty steel frame to take the place of the engine block in the structure, and then a battery pack that’s beautifully built. The final tractor at the end of the video still has a few additions before it’s finished, but it’s a usable machine we wouldn’t be ashamed to have for small round-the-farm tasks.

Surprisingly there haven’t been as many electric tractors on these pages as you’d expect, though we’ve seen some commercial ones.

Continue reading “An Electric Vehicle Conversion With A Difference” →