Enormous Metal Sculpture Becomes An Antenna

March 23, 2023 by Bryan Cockfield 16 Comments

Those who have worked with high voltage know well enough that anything can be a conductor at high enough voltages. Similarly, amateur radio operators will jump at any chance to turn a random object into an antenna. Flag poles, gutters, and even streams of water can be turned into radiating elements for a transmitter, but the members of this amateur radio club were thinking a little bit bigger when they hooked up their transmitter to this giant sculpture.

For those who haven’t been to the Rochester Institute of Technology (RIT) in upstate New York, the enormous metal behemoth is not a subtle piece of artwork and sits right at the entrance to the university. It’s over 70 feet tall and made out of bronze and steel, a dream for any amateur radio operator. With the university’s permission and some help to ensure everyone’s safety during the operation, the group attached a feedline to the sculpture with a magnet, while the shield wire was attached to a ground rod nearby. A Yaesu FT-991 running on only 5 watts and transmitting in the 20-meter band was able to make contacts throughout much of the eastern United States with this setup.

This project actually started as an in-joke within the radio club, as reported by Reddit user [bbbbbthatsfivebees] who is a member. Eventually the joke became reality, as the sculpture is almost a perfect antenna for certain ham bands. Others in the comments noted that they might have better luck with lower frequency bands such as the 40-meter band or possibly the 60-meter band, due to the height of the structure. And, for those who are still wondering if you really can use a stream of water to transmit radio waves, it is indeed possible.

Illuminating Origami Is Just Around The Corner

January 12, 2022 by Michael Shaub 13 Comments

Pop-up greeting cards are about to get a whole lot more interesting. Researchers at Seoul National University in Korea have created glowing 3D objects with a series of prototypes that fold thin QLED (Quantum Dot LED) sheets like origami. They used a CO₂ laser to etch “fold lines” in the QLED so the sheets could be formed into 3D shapes. The bends are actually rounded, but at 5μm they appear to be sharp corners and the panels continue to illuminate across the fold lines for at least 500 folds. Some glow in solid colors, while others use smaller addressable areas to create animated matrix displays of patterns and letterforms. See the short video after the break, read the Physics World article or to see all the prototypes and dig into details of the full research paper in Nature (freed from the paywall by SharedIt).

Folded QLED Panels – forming a pyramid and a cube

Folded QLED Panels – various patterns and the 3D forms they fold into

We’re not sure how soon this technique can be duplicated in our home labs, but we can’t wait to fold up our own 3D lights and matrices. Until then, check out some glowing origami you can make right now from [Charlyn Gonda] at Remoticon 2020 and earlier that year and this amazing origami lamp.

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My Major Is Gaming…

December 6, 2021 by Al Williams 12 Comments

Times have changed. You can now take a university class in writing games. In fact, YOU can now take a university class about writing games because [Dave Churchill] of Memorial University has put all 22 of his lectures up for your enjoyment. [Dr. Churchill] isn’t planning on releasing the assignment files, but you can still get a lot from watching the videos. Apparently, the classes were also live streamed on Twitch.

The games build on SFML so the resulting games can be portable. The library abstracts input, graphics, sound, and networking.

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Grab A Stanford Computer Science Education

October 14, 2020 by Al Williams 18 Comments

There are two reasons to go to school: learn about something and to get a coveted piece of paper that helps you get jobs, or at least, job interviews. With so many schools putting material online, you can do the first part without spending much money as long as you don’t expect the school to help you or grant you that piece of paper. Stanford has a huge computer science department and [Rui Ma] cataloged over 150 computer science classes available online in some form from the University. Just the thing to while away time during the quarantine.

Apparently, [Rui] grabbed the 2020 course catalog to find on-campus classes and found the companion website for each class, organizing them for our benefit. The list doesn’t include the actual online class offerings, which you can find directly from Stanford, although there is another list for that.

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Quadcopter With Stereo Vision

June 30, 2020 by Bryan Cockfield 5 Comments

Flying a quadcopter or other drone can be pretty exciting, especially when using the video signal to do the flying. It’s almost like a real-life video game or flight simulator in a way, except the aircraft is physically real. To bring this experience even closer to the reality of flying, [Kevin] implemented stereo vision on his quadcopter which also adds an impressive amount of functionality to his drone.

While he doesn’t use this particular setup for drone racing or virtual reality, there are some other interesting things that [Kevin] is able to do with it. The cameras, both ESP32 camera modules, can make use of their combined stereo vision capability to determine distances to objects. By leveraging cloud computing services from Amazon to offload some of the processing demands, the quadcopter is able to recognize faces and keep the drone flying at a fixed distance from that face without needing power-hungry computing onboard.

There are a lot of other abilities that this drone unlocks by offloading its resource-hungry tasks to the cloud. It can be flown by using a smartphone or tablet, and has its own web client where its user can observe the facial recognition being performed. Presumably it wouldn’t be too difficult to use this drone for other tasks where having stereoscopic vision is a requirement.

Thanks to [Ilya Mikhelson], a professor at Northwestern University, for this tip about a student’s project.

A Car That Runs On Homemade Chemical Reactions

December 25, 2019 by Sharon Lin 10 Comments

The race for chemical engineering is quite literally on. Every year, the American Institute of Chemical Engineers (AlChE) brings together hundreds of university students to face-off to design the fastest car using techniques they’ve learned from chemical engineering courses.

The Chem-E-Car competition races cars which are only powered by chemical reactions. The goal is to come up with an elegant solution – you can’t simply jettison matter out the back as the method of locomotion. In particular, the rules don’t allow the use of liquid or obnoxious odor discharge, commercial batteries, brakes, or electrical/mechanical timing devices. However, this doesn’t mean that electronics are absent from these designs. Many teams must gather data in order to design a control system to improve the performance of their car.

Students have to build a power system, stopping mechanism, circuitry, and mechanical assembly for the body of the car, all to fit in a size constraint not much bigger than a shoebox. The competition primarily judges the accuracy of the chemical reaction for stopping the car more so than speed or power. Given that the load the car must carry is typically unknown until the day of the competition, this is a significant challenge, allowing teams to find a way to design a flexible reaction that can accommodate a range of loads and distances.

For example, this 2015 entry from the Rice University team (PDF) uses a fuel cell for locomotion and an iodine clock reaction as a timer for braking. The fuel cell powers an Arduino which monitors a light-dependent resistor. In between the LED and that LDR, the clock reaction turns opaque at a predictable time and triggers the motors to stop turning.

While many schools choose not to disclose their designs in order to gain a competitive edge, we applaud the teams who have shared the story of their builds. Kudos to the Rice team mentioned above, to the 2014 Rutger’s team whose white paper outlines the construction of aluminum air batteries worthy of Walter White, to the car from the Universitas Negeri Semarang, Indonesia powered by a thermoelectric generator (PDF), the UC Berkeley team for outlining numerous approaches to developing their power system, and the two Ohio State team’s entries seen winning the regional competition in the video below.

If you were on a team that compete the the Chem-E-Car, we want to hear about it!

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The Young Engineers Guide To University Capstone Projects

November 26, 2019 by Lewin Day 8 Comments

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” →