SFU students are sending a tiny centrifuge into space. It could help long-haul astronauts stay healthy
The model is only a couple of inches in diameter, while the full-scale version they hope to fit future spacecrafts with would have a two-metre radius.
A tiny SFU-built centrifuge is heading into low-earth orbit later this year or early next, and it could have a big impact on the health of future astronauts.
AleaSat is a joint project between the SFU Satellite Design Team and UBC Orbit, and the group’s small satellite will allow them to test out a scaled-down model of centrifuge that could ultimately help astronauts maintain muscle mass and bone density.
The name AleaSat combines “satellite” with the Latin word “alea,” the Latin word for dice or a game of chance. SFU said in a news release that the name was chosen because the project “represents a unique opportunity for students” to see something they’ve worked on sent out beyond Earth’s atmosphere.
Donya Divsalar is a masters student in science with SFU’s Aerospace Physiology Laboratory and the science lead on AleaSat, a joint project between the SFU. Speaking from Toulouse, France, she told Burnaby Beacon the project has included up to nearly 80 people working on it in various capacities, including students in business, engineering, and sciences.
Not like in the movies
The project itself is to launch a miniature prototype of a short-arm centrifuge—something they believe will help mitigate some of the effects of space on the human body.
“When we go to space, all the fluids in our body shift upwards because there is microgravity,” Divsalar said.
“So for long-term space missions—going to the moon or Mars—we need a mechanism that would simulate Earth-like conditions.”
Short-arm centrifuges have been designed elsewhere in the world, particularly through the European Space Agency. But this one would be the first to be entirely built and designed in Canada.
In movies like The Martian or 2001: A Space Odyssey, spacecraft are often seen with some version of a centrifuge to generate a gravity-like force in sections of a spaceship.
But Andrew Blaber, an SFU professor and head of the Aerospace Physiology Lab, said they don’t exactly comport with science.
“If you do the calculations, he would be tripping when he’s climbing down the ladder. His feet would fly out from under him, because his feet would be traveling faster than his hands on the ladder,” he said of 2001.
“You need a much bigger radius for that.”
Prepare for liftoff! @SFU_Satellite & @UBCOrbit have partnered to design & build a satellite that will be launched into orbit onboard a @SpaceX rocket. @MDA_space @SFU_Science https://t.co/jR59OGi5N0 pic.twitter.com/j631OINdl0
— Simon Fraser University (@SFU) April 4, 2022
Exercise in a centrifuge
Blaber compared the centrifuge the AleaSat team is working on to a merry-go-round.
“If you lie down with your head at the centre of the merry-go-round and hold on tight, and they spin it, that’s basically a short arm centrifuge,” Blaber said.
“So the head is near the centre, and the feet are on the outside. And of course, what that does is that shifts your bodily fluids towards the feet, which is similar to what happens with gravity when you’re standing.”
Blaber said the direction in which the force is applied, between gravity and a centrifuge, is different, but it “does the job in terms of applying forces on the body similar to what we would see with gravity.”
What, exactly, the difference is, however, is being looked at now—and that’s why Divsalar is in Toulouse.
In the tests she is running, including a full-scale centrifuge, participants are staying in bed for 60 days to simulate the flow of bodily fluids during spaceflight. And some of the participants will exercise in artificial gravity generated by the centrifuge.
The effects of that exercise on their health will then be compared to those who don’t do the exercise.
“We already know what happens when you don’t do it—it’s very drastic, in terms of degradation of the bone, muscle mass, and cardiovascular system,” Blaber said.
“So it’s hoped that artificial gravity with exercise is going to help that, but we don’t know the dose that will do it.”
Divsalar said the data she collects in Toulouse will be “vital” to the work on the centrifuge they design at SFU.
“It is fundamental to the design of the device itself and to give us more information on how we can better improve astronaut health when going to the moon and Mars,” she said.
Floating in a most peculiar way
The next big experiment, however, will actually take the group’s work into space.
The reason the group is sending a miniature model—measuring a cube of 10cm by 10cm by 10cm—of the centrifuge into space is to gauge how it would impact the vessel it’s integrated into.
The group needs to study how the spin of the centrifuge to generate that gravity-like force will impact a vessel in microgravity to help inform the design.
The group’s centrifuge will, at full scale, have a radius of two metres, Blaber said.
AleaSat project manager Kevin Burville, a recent SFU alum and co-founder of SFU Aerospace, said the small satellite will include a scale model of the centrifuge, about a couple of inches in diameter.
“Really, what we’re trying to do is look at the effects that this has on a spacecraft in orbit at a small, affordable scale,” Burville said.
“We want to look at things like vibration and torque and how this affects the spacecraft. … Measuring the orientation of the craft and how that changes because of these spinning systems, it’s not something you necessarily think about, but with the complex physics of the momentum and inertia involved in these systems, you actually have major effects on the spacecraft itself.”
Sitting in a tin can
On the International Space Station, astronauts do exercise on treadmills, often referred to as Colbert treadmills, in an effort to maintain some of their bone density and muscle mass. But it has to be done with a Vibration Isolation Stabilization System to keep the vibrations from their exercise routines from disrupting the delicate microgravity experiments being conducted on the station.
“The device[s] that’s currently on board the ISS are pretty impressive, and they’ve been there for a long time. There’s a lot of research that’s been done with them,” Divsalar said.
“However, what we found is that none of them really fully activates all the body systems in order to combat those effects, those downsides that happened to the human body through microgravity and [a] long-term stay in space.”
This is particularly important for longer times in space. The average mission on the ISS is six months—by comparison, a trip to Mars is expected to take about seven months, and that’s not including a return trip.
“With that comes the need for a different exercise module, different countermeasures for space health,” Divsalar said.
A little weight, a lot of fuel
The design of the device is also going to need to take into account its mass, Blaber noted. While the ISS was built over 20 years with numerous launches carrying payloads of various items and equipment, including the specialized treadmill station.
A mission to Mars, however, is going to be done with just one launch, so the weight of the equipment included in the vehicle is important—particularly when it comes to fuel.
To achieve orbit, or escape it entirely, a rocket needs to reach speeds of about 40,000 km/h, which means a lot of fuel is necessary. In fact, generally speaking, experts say a rocket’s fuel should account for about 90% of the rocket’s overall weight, including payload.
That means each kilogram added to the payload requires more than nine kilograms of fuel.
The scaled-down model of the centrifuge is effectively ready for launch—though the model they currently have will probably be replaced with a new model made and kept in a cleanroom to keep any issues like dust or other potentially problematic particles from infiltrating it.
And the craft will head into space either sometime late this year or early next year.
And it will do it through “essentially a rideshare with a SpaceX rocket,” Burville said.
‘We do it because we love it’
While spaceflight slowed in the 2000s and 2010s, privatization in the industry has significantly increased the number of opportunities for researchers to get their projects into space.
And those working on the AleaSat project say they’re more than pleased to have the opportunity.
“It feels out of this world—not to be too punny about it, but it feels great,” Divsalar said.
What makes the achievement even sweeter, she said, is that the funding for the project was entirely raised by those involved.
“Most of these projects are done through student competitions, where we had to basically go through everything ourselves—secure our own funding, secure our own launch, do all of our own licensing, and we’re learning a lot,” Divsalar said.
“And it is a lot of volunteer work. None of us are really paid to do it. We do it because we love it.”
On top of getting a piece of their labour into space, the group is also looking at getting something a little more symbolic into orbit as well.
“We’ve talked about a few interesting things that we want to do,” Burville said.
“We talked about trying to make sure that we can get student names inscribed in the satellite, and we’re going to have our sponsors’ logos and stuff like that. So we’re working to try and have fun things like that.”