Want to generate some thrust by way of an exposed high voltage discharge that looks great when you turn down the lights? [Integza] has a video showing how to do exactly that with some simple components. His little thruster manages to blow out candles at surprising distances before being pressed into service propelling a model boat.
Here’s how it works: ionic wind is generated when a strong enough electric field causes nearby air to ionize, for example from sharp tips of a conductor carrying a high enough voltage. This discharge creates ionized air molecules with an electrical charge matching the polarity of the nearby conductor. Because matching polarities repel one another, the small cloud of ionized air molecules are repelled from both the nearby conductor, as well as from each other.
The result is a wind-like force from a device with no moving parts, and if the parts are structured right, it’ll blow out a candle with ease. [Integza] attached a cheap DC high-voltage transformer to a nickel strip cut into sharp points and rolled into a circlet. The other half of the thruster — in contrast to the thin crown of sharp points — is a smooth ring shaped a little like a thruster nozzle. 3D models of the parts are available online should you wish to try it yourself without all the trial and error of trying to optimize.
In an effort to minimize mass, [Integza] electroplates a 3D-printed version of the large ring with great results, spraying it with graphite first to make it conductive. Cheap and safe copper electroplating is entirely within the reach of hobbyists, and the resulting unit does a pretty nice job. You can watch it in action in the video, embedded below.
Over the last several months, we’ve been enjoying a front-row seat as [Jay Bowles] of Plasma Channel has been developing and perfecting his design for a high voltage multi-stage ionic thruster. With each installment, the unit has become smaller, lighter, and more powerful. Which is important, as the ultimate goal is to power an RC aircraft with them.
There’s still plenty of work to be done before [Jay] will be able to take his creation skyward, but he’s making all the right moves. As a step towards his goal, he recently teamed up with [RcTestFlight] to attach a pair of his thrusters — which have again been further tweaked and refined since we last saw them — to a custom catamaran hull. The result is a futuristic craft that skims across the water with no moving parts and no noise…if you don’t count the occasional stray arc from the 40,000 volts screaming through its experimental thrusters, anyway. Continue reading “High Voltage Ion Engines Take Trip On The High Seas”→
When [Jay Bowles] demoed his first-generation ion thruster on Plasma Channel, the resulting video picked up millions of views and got hobbyists and professionals alike talking. While ionic lifters are nothing new, this robust multi-stage thruster looked (and sounded) more like a miniature jet engine than anything that had come before it. Optimizations would need to be made if there was even a chance to put the high-voltage powerplant to use, but [Jay] was clearly onto something.
Anyone who’s looked into high-voltage experiments is likely familiar with ion lifters — spindly contraptions made of wire and aluminum foil that are able to float above the workbench on a column of ionized air. It’s an impressive trick that’s been around since the 1950s, but the concept has yet to show any practical application as the thrust generated isn’t nearly enough to lift a more substantial vehicle.
It’s a bit early to suggest that [Jay Bowles] of Plasma Channel has finally found the solution to this fundamental shortcoming of electrostatic propulsion, but his recently completed multi-stage ion thruster certainly represents something of a generational leap for the technology. By combining multiple pairs of electrodes and experimentally determining the optimal values for their spacing and operational voltage, he’s been able to achieve a sustained exhaust velocity of 2.3 meters per second.
While most ion thrusters are lucky to get a piece of paper fluttering for their trouble, [Jay] demonstrates his creation blowing out candles at a distance of a meter or more. But perhaps the most impressive quality of this build is the sound — unlike most of the experimental ion thrusters we’ve seen, the air flowing through this contraption actually makes an audible roaring sound. When the 45 kilovolt supply voltage kicks in it sounds like a hair drier, except here there’s no moving parts involved.
In addition to providing graphs that show how air velocity was impacted by input voltage and the number and spacing of the electrode pairs, [Jay] also pops the thruster on a scale to show that there is indeed a measurable thrust being produced. Admittedly the 22 grams of thrust being generated isn’t much compared to the contraption’s own mass of 490 grams, but in the world of electrostatic propulsion, those are pretty impressive numbers.
[Jay] says he has some improvements in mind that he believes will significantly improve the device’s performance as he works towards his ultimate goal of actually flying an ion-propelled aircraft. We saw MIT do it back in 2018, and it would be great to see an individual experimenter pull off a similar feat. Obviously, there’s still a long way to go before this thing takes to the skies, but if anyone can pull it off, it’s [Jay Bowles].
The field of space vehicle design is obsessed with efficiency by necessity. The cost to do anything in space is astronomical, and also heavily tied to launch weight. Thus, any technology or technique that can bring those figures down is prime for exploitation.
In recent years, mercury thrusters promised to be one such technology. The only catch was the potentially-ruinous environmental cost. Today, we’ll look at the benefits of mercury thrusters, and how they came to be outlawed in short order.
An unfortunate property of science-fiction is that it is, tragically, fiction. Instead of soaring between the stars and countless galaxies out there, we find ourselves hitherto confined to this planet we call Earth. Only a handful of human beings have ever made it as far as the Earth’s solitary moon, and just two of our unmanned probes have made it out of the Earth’s solar system after many decades of travel. It’s enough to make one despair that we’ll never get anywhere near the fantastic future that was seemingly promised to us by science-fiction.
Yet perhaps not all hope is lost. Over the past decades, we have improved our chemical rockets, are experimenting with various types of nuclear rockets, and ion thrusters are a common feature on modern satellites as well as for missions within the solar system. And even if the hype around the EMDrive vanished as quickly as it had appeared, the Alcubierre faster-than-light drive is still a tantalizing possibility after many years of refinements.
Even as physics conspires against our desire for a life among the stars, what do our current chances look like? Let’s have a look at the propulsion methods which we have today, and what we can look forward to with varying degrees of certainty.
It seems as though every week we see something that clearly shows we’re living in the future. The components we routinely incorporate into our projects would have seemed like science fiction only a few short years ago, but now we buy them online and have them shipped to us for pennies. And what can say we’ve arrived in the future more than off-the-shelf plasma thrusters for the DIY microsatellite market?
Although [Michael Bretti] does tell us that he plans to sell these thrusters eventually, they’re not quite ready for the market yet. The AIS-gPPT3-1C series that’s currently under testing is designed for the micro-est of satellites, the PocketQube, a format with a unit size only 5 cm on a side – an eighth the size of a 1U CubeSat. The thrusters are solid-fueled, with blocks of Teflon, PEEK, or Ultem that are ablated by a stream of plasma. The gaseous exhaust is accelerated and shaped by a magnetic nozzle that’s integrated right into the thruster. The thruster is mounted directly to a PCB containing the high-voltage supplies and control electronics to interface with the PocketQube’s systems. The 34-gram thrusters have enough fuel for perhaps 500 firings, although that and the specifics of performance are yet to be tested.