Updated July 6 to reflect change in Psyche’s launch date.
A spacecraft called Psyche is under development by NASA. The launch date is uncertain, but could be as soon as 2023 or 2024. If all goes well, Psyche will rendezvous with a metal-rich asteroid, also called Psyche.
Built at NASA’s Jet Propulsion Laboratory, Psyche, like other spacecraft, consists of thousands of parts which must perform correctly to avoid a failure which could ruin some or all of a nearly $1 billion mission.
One of the parts builders for Psyche is Dan Sable of Blacksburg’s VPT, Inc. When Psyche rises atop a SpaceX Falcon Heavy rocket at NASA’s famed Launch Complex 39A, Sable’s good reputation in the industry will be riding with it.
Said Sable in an interview with Cardinal News: “The business is not for the faint of heart. I’ll just say that.”
VPT was founded in 1993 by Sable, Fred Lee and Gary Hua. The company was sold to Heico Corporation in 2009 but Sable remains as CEO.
Sable said that due to a legal agreement he could not say what the VP in VPT stands for, or used to stand for, but that it does not stand for Virginia Power.
Headquartered at Virginia Tech’s Corporate Research Center, VPT is the world’s leading supplier of advanced DC-DC power converters for military and space applications, according to its website. The parts are designed in Blacksburg; most of the manufacturing is in Taiwan.
Power converters change a given DC voltage to another. They are used in all sorts of products, like cars and computers, where conversion of voltage is needed. But VPT’s are no ordinary power converters.
Outer space, seemingly so empty, is bathed in radiation.
“Occasionally, giant explosions, called solar flares, occur on the surface of the Sun and release massive amounts of energy out into space in the form of X-rays, gamma rays, and streams of protons and electrons,” according to “Why Space Radiation Matters” on nasa.gov. “These solar flares can have serious consequences to astronauts and their equipment, even at locations that are far from the Sun.”
Solar flares “can really upset semiconductors,” Sable said.
Another hazard is galactic cosmic radiation. “GCR comes from outside the solar system but primarily from within our Milky Way galaxy,” the NASA site said. “GCR is composed of the nuclei of atoms that have had their surrounding electrons stripped away and are traveling at nearly the speed of light … the nucleus of any element in the periodic table from hydrogen to uranium. Now imagine that same nucleus moving at an incredibly high speed.”
Much radiation in space is ionizing, meaning it knocks electrons from their orbits. “Ionizing radiation is like an atomic-scale cannonball that blasts through material, leaving significant damage behind,” the NASA article said.
VPT’s converters have to be radiation-proof. “That’s a very involved process, and it gets very expensive too,” Sable said. “A power converter that may cost $50 in a commercial world may cost $5,000 to be radiation-hardened.
“We spend a lot of time on design, analysis, testing, retesting, qualification, just for the radiation requirements alone. We actually spent years developing what they call a Radiation Hardness Assurance plan that could be blessed by NASA. And we were spending a fortune on radiation testing. And so we actually wound up buying our own radiation test lab.”
VPT Radiation Laboratory and Test Services (VPT Rad), located in Massachusetts, uses cobalt-60 irradiators to test aerospace devices.
VPT devices power the two main imagers on Psyche, according to Mike Malin of Malin Space Science Systems, which built the imagers.
Psyche, the asteroid, is about 140 miles in diameter and composed mostly of metal. After a 3.5 year journey, including a gravity assist from Mars, the spacecraft will orbit the asteroid for 21 months. The imagers will study Psyche in the visible-light spectrum and also in the ultraviolet and infrared bands. Among other things, scientists hope the study of the giant potato-shaped lump of metal will help them better understand Earth’s metallic core.
Psyche isn’t the only NASA mission to use VPT parts. The Perseverance rover, launched in 2020 and still roaming the Red Planet, incorporates a VPT converter. It powered the Lander Vision System Camera (LCAM) which was critical in helping Perseverance land safely on Feb. 18, 2021. Had the VPT part failed, Perseverance could have ended up as $2.7 billion worth of rubbish strewn over Mars’ red dust.
Like many other spacecraft Perseverance is powered by the radioactive decay of plutonium — in this case, 10.6 pounds of plutonium dioxide. The VPT part takes voltage from the main power circuit and converts it to the level required by the camera.
The camera was a key component of a system called Terrain Relative Navigation, which was developed by Andrew Johnson and his team at Jet Propulsion Laboratory.
TRN “is used during landing to figure out where the lander is, so that it can avoid large hazards that are there on Mars, so it doesn’t land on top of them,” Johnson said. During rocket-powered descent, the camera takes pictures which are compared to images taken from orbit.
“Once we got to about 4.2 kilometers [altitude], that’s when we started using the camera for its intended purpose,” Johnson said. “Those images were taken about once a second, and then all the way down to 500 meters altitude. And then, we took some images all the way down to the ground as well.”
The camera is located on the front left corner of the rover, pointing down. Having fulfilled its purpose, it is no longer in use.
Closer to home, VPT parts are used in GPS satellites. Sable admitted he was nervous when the first GPS orbiter launched with a VPT part, in 2005.
“Since then they have launched another 23 GPS satellites with our parts,” he said. “You don’t really get used to it for big, high visibility programs like that. I tell folks that if their GPS ever stops working, it’s probably because our power converters have failed. Knock on wood, that has not happened as of yet.”
Sable, 64, has been involved in the space industry since 1978 when he was a co-op student at RCA Astro-Electronics. He went on to get a Ph.D. in electrical engineering from Virginia Tech.
To succeed, like Sable has, as an engineer/entrepreneur, “it takes a visionary who is not afraid to put in the long hours to realize a dream,” said Brett Malone, president and CEO of the CRC.
Many have dreamed of setting foot on Mars or visiting the asteroid belt. Until that happens, orbiters like Psyche and rovers like Perseverance serve as our eyes and hands.
Said Sable: “I really do get a kick out of seeing our products help in exploring the solar system.”