A conversation with Jose Benavides, engineer with the Advanced Control and Evolvable Systems Group in the Intelligent Systems Division at NASA’s Ames Research Center in Silicon Valley.
Transcript
Matthew Buffington (Host): Welcome to NASA in Silicon Valley episode 37 and more importantly for today, May the fourth be with you. To honor our space counterparts in a galaxy far, far away, we have with us NASA engineer, Jose Benavides. Jose works on a project called SPHERES, which is a clever acronym for the Synchronized Position Hold Engage and Reorient Experimental Satellite. SPHERES is a small, semi-autonomous robot about the size of a volleyball that floats around the International Space Station running experiments. It is a really cool testament to how technology drives exploration and also how the ISS is working off the Earth, for the Earth. So put away your blasters and lightsabers and witness the firepower of this fully armed and operational battle station… er I meant podcast. Anyways, here is Jose Benavides.
[Music]
Host:We always like to start it off, tell us a little bit about yourself. How did you join NASA? How did you get to Silicon Valley?
Jose Benavides: Right out of school, actually.
Host:Nice.
Jose Benavides: Actually, I hadn’t even graduated yet. A professor I work with at Arizona State got me an interview with a person here at NASA Ames, and I got the job. I was really excited. Like many people, I idolize NASA and really excited. I did grow up there outside of Phoenix. I went to school at Arizona State there in Tempe. I was more than happy to move out to NASA Ames for a job.
Host:It didn’t start off as an internship or anything? You just saw a job posting?
Jose Benavides: Actually, I didn’t see the job posting. I was referred by my professor. My advisor, actually, there at Arizona State knew a friend here at NASA Ames looking for someone with my background and got me the interview. I flew out here for the interview.
Host:So it just worked out perfectly?
Jose Benavides: Yeah, it worked out really well. It was a contractor position in a controls group here at NASA Ames working on hypersonic aircraft.
Host:Wow.
Jose Benavides: To my mind, how cool is that? Right? So I jumped on it and together with my wife came out here and I started the job.
Host:What was it like those early days? You came out. You work on a hypersonic aircraft.
Jose Benavides: Yeah, so that was really cool.
Host:Yeah.
Jose Benavides: That actually stemmed out of work my advisor was working on, and I got to support him a little bit on that. It focused on the design of scramjet-powered hypersonic aircraft. So more specifically, the controls-centered design. So how do you design an aircraft to be more easily controlled?
Host:Okay.
Jose Benavides: As it turns out, that was a very important aspect for these hypersonic aircraft because their performance margins are razor thin and very high performance. Their controllability was very different than a standard aircraft, right? A standard aircraft, you have a pilot, they control them this way and that. But when you’re going Mach 10.
Host:I was going to say, you’re going faster than a speeding bullet.
Jose Benavides: Yeah, you’re going Mach 10. And then compounding that is the fact that you’re using scramjet engines, which pull the oxygen out of the air
Host:Wow.
Jose Benavides: The combustion doesn’t involve any moving parts. Once you’re going those speeds, you can compress your air into a combustible form. And the angle at which the aircraft is going has a huge impact on how that engine performs. So you have to control the aircraft in a very special way.
And so we were looking at,how can the whole aircraft be designed in such a way that it’s more easily controlled, allow the standard processes for aircraft designs involve designing aircraft to meet certain static performance measures, so it can hold a certain amount of weight, it can fly straight and static really well. But then they throw it over the fence to controls engineers who then look at it in a more dynamic way. When you control it this way and that, is it not going to pitch too much and explode.
Host:Wow.
Jose Benavides: We were looking at how do you design these things to be more easily controlled.
Host:One of the fun things about being at NASA at a research center is there’s such a really diverse portfolio where you have aeronautics, wind tunnels and hypersonic aircraft, but on the other side also robotics and astrobiology and exoplanets. So how did that move from you working on these aircraft into right now being in the robotic division? How did that process happen?
Jose Benavides: I am working on a project called SPHERES and what’s going to become the Astrobee facility.
Host:So for folks listening who have no clue what SPHERES is.
Jose Benavides: Yeah. I did recommend anybody to go out and take a look. It’s made the headlines a few times. NASA.gov/SPHERES, easy enough.
Host:It’s spelled correctly, though it’s still an acronym.
Jose Benavides: Right. Right. So just like the shape, it’s spelled in the same way. It is an acronym. It’s basically a volleyball-sized small satellite that operates inside the International Space Station. So the common reference I’ll use in referring people is it’s exactly like the droid on Star Wars.
Host:This is the little floating ball.
Jose Benavides: It’s a floating ball on the Millennium Falcon where Luke Skywalker is —
Host:Training with his lightsaber.
Jose Benavides: — training with his lightsaber, absolutely.
Host:It’s true. It’s a little ball that’s floating around.
Jose Benavides: And as the story goes, there was an MIT professor who showed that clip of Star Wars to his senior design class and said, “Hey guys, I want you to build this.” And sure enough, together with some DARPA funding, that’s exactly what they did. They built three of these things, sent them up to the space station. First operated in 2006.
Host:Okay.
Jose Benavides: They’ve been in continuous operation ever since. Well over 10 years now that SPHERES has been in operation on ISS, initially designed by MIT to look at things like automated docking, formation flight, controls algorithms. It’s since then been used for all kinds of research because in 2010, it was transitioned to NASA Ames to be managed as a facility on the Space Station.
Host:Okay.
Jose Benavides: Where we cater to researchers all around the country that use SPHERES as a testbed on ISS to study all kinds of different things from the sloshing of upper stage rocket fuel to electromagnetic formation flight, different kinds of propulsion, in-space assembly, robotic interactions with crew on ISS. So all kinds of really cool research, even outreach. There’s this really cool program MIT leads called Zero Robotics.
Host:Okay.
Jose Benavides: Yeah, it’s very similar to FIRST Robotics, if you’ve heard of that.
Host:High schools. Yeah, robotic competitions.
Jose Benavides: Exactly. They form robot clubs and they compete with other high schools all around the country and the robots they build. Except with Zero Robotics, it’s more programing-focused. And then of course the finals takes place on the space station.
Host:Really?
Jose Benavides: Narrated by the [astronaut] crew themselves in real time. The students travel to MIT and witness their code operating on the International Space Station.
Host:So it’s like you have these balls floating around in the space station. Students, folks, could be like, “All right, we’re going to take over. We have a science experiment and we’re going to take over these balls.”
Jose Benavides: Absolutely. Just like FIRST Robotics, the game changes every year. There’s actually a virtual game overlaid onto the SPHERES hardware where the students, for example, one year were programming the SPHERES to repel asteroids from crashing into Earth, or this latest year they were deploying GPS satellites on Mars. So this whole virtual game that they’re programming to. And then they earn points and compete with the other teams across the country and across the world. There are teams in Europe and Australia. So it’s a truly international competition.
Host:And so just slightly going back to question before, I’m just fascinated by SPHERES, how did you end up going from working on the planes to working on SPHERES? Yeah, how does that go?
Jose Benavides: Also my background is in controls engineering. My Bachelor’s and Master’s degree is in electrical engineering, but emphasizing controls. And that gives me the flexibility to work on all kinds of different projects that may utilize my controls training as well as my background in embedded systems.
So I actually did intern for many years at a company. They specialize in embedded systems. Those are the small computers that go into appliances, small computers that go into anything intelligent, right? I got to learn about how to program those things, how to design circuits, how to design those types of applications.
I had a background in both controls engineering, electrical engineering, as well as hardware design and software development. So with that kind of background, I was able to come to NASA initially working on hypersonic aircraft. Where we were looking at the mathematical models that dictate how a hypersonic aircraft flies, and then the ensuing controls algorithms needed to keep that stable.
From there, I went to a project called TFMS, Tactical Flight Management System, where we were looking at the autopilot in general transport aircraft, the kind we would fly any day of the week. The 747, 737 Boeing aircraft where there is this flight management computer in the cockpit that a pilot programs his flight plan into and then can turn on the autopilot to fly a particular flight plan.
And we were looking at ways of making that more intelligent, more safe, basically so that the pilot can be better aware of what the autopilot is doing.
Host:Okay.
Jose Benavides: There are scenarios where the pilot might not be aware of exactly which mode or what objectives the autopilot is doing. So is there a way to put more intelligence into a flight management computer and the autopilots to better communicate that information to the crew of an aircraft? And so I worked on that for a little while.
But in 2010, I came on as an engineer with the SPHERES facility project here at Ames when it was transitioned here from MIT. Yeah, I’ve been with that project ever since, really. And to this day, I’m now the project manager for that SPHERES facility. Support researchers all over the country utilize the SPHERES platform.
Host:I know whenever we bring people over, like tours or the press come over, it’s like showing off SPHERES, it’s always the go-to place because you can actually see it in your lab and see the balls and then see video of how they operate up on the Space Station.
Jose Benavides: Yeah, yeah. It’s great to do those tours. It certainly draws the eyes as you see these things that can move across our granite table where we test these out, as well as our MGTF, our Microgravity Test Facility, where they can be operated on a gantry and where they can really be tested at least kind of like they might fly in space.
Host:I was going to say, that seems to be the biggest difference. Even for students or people who are putting code into the SPHERES, into the robotics, how do you even test that in a lab when you have gravity? Obviously, the thing that makes it float up on the space station is that there is zero gravity.
Jose Benavides: No gravity.
Host:How do you do that?
Jose Benavides: First off, it is very much a unique environment, and that’s why we have the space station. We have a very risk tolerant environment on the space station. It’s basically a lab up in space where we can prototype things, test things. And that’s the big benefit of SPHERES on station is we can test out algorithms and software that may have a bug, some things might go wrong, where we just ask the crew to go over and push a reset button. No big deal. But if something like that happens on a dedicated satellite or far more expensive item, then you’re having a really bad day.
Host:Yeah.
Jose Benavides: So the big benefit of having ISS is being able to do prototypes and testing of technologies in a very risk-tolerant environment. So that’s a big part of what SPHERES can do on ISS is take advantage of that microgravity environment. But we still want to do our testing on the ground as much as we can before we send it up to ISS, and that’s where our labs come in. The granite lab is where we can do that in part where basically we have a reverse air hockey table. If you’ve ever been to an arcade, you’ve played air hockey.
Host:Air blowing up.
Jose Benavides: Exactly.
Host:Keeps it afloat.
Jose Benavides: Air blowing up and it allows the puck to move across the surface with almost no friction.
Host:Friction, yeah.
Jose Benavides: It’s really smooth. And that’s what we need to be able to approximate microgravity in at least three degrees of freedom. Right? So left, right, up, down and then in rotation.
Host:Okay.
Jose Benavides: It can move across the table as if it’s in space because there’s no friction. Right? Up in space, in microgravity, you set something going, it’s going to keep going forever until something slows it down. Right? On the table, that’s what we have is a very flat, very smooth granite table. And then it’s the air carriage on the table that has these pucks fed by a compressed CO2 that forms that cushion of air between the air carriage and the table, and it can slide across with almost no friction. And then it’s the built-in propulsion of the SPHERES unit that moves it around just like it would up on space.
Host:Even on that, you figure that you have the gravity pulling down and then you have the air hockey table, pulling up.
Jose Benavides: Right. Again, it’s that gravity, that pesky gravity vector that gets in the way. And that’s why the granite table has to be to within half a paper’s width difference from one end of the table to the other. And we’re talking a good three meters across.
Host:Wow.
Jose Benavides: Because the slightest incline in that table, the air carriage is going to start —
Host:It’s just going to fall.
Jose Benavides: Yeah, the air carriage is going to start moving. If we want to approximate space, if something sat still, it’s going to remain still forever.
Host:Yeah.
Jose Benavides: And that’s what we need it to do on the table. So a very flat, very smooth surface with no incline, or at least as small as we can get.
Host:And so basically no friction, but you want to put it so if it’s going to move, it’s going to move on its own accord.
Jose Benavides: Exactly.
Host:Yeah.
Jose Benavides: Exactly.
Host:But even still, you figure that’s still almost like a 2-D kind of plane because it’s not going vertical.
Jose Benavides: Right. There’s no vertical motion. It’s all 2-D. And then together with it’s rotation, we can consider it at 3-DOF, 3-degrees-of-freedom motion.
Host:Yeah.
Jose Benavides: And so that’s where we then go over to our MGTF.
Host:Okay. What is that? Tell me.
Jose Benavides: Just like the granite table, it gives us the world’s best air hockey table. In the MGTF we have the world’s best crane game.
Host:Okay.
Jose Benavides: I’m just joking about that. But it’s basically a big gantry, a bit contraption that can move something in a full 6 degrees of freedom across a module. What we have there is the mockup of the JEM module on ISS and this big gantry that can move free flyer, like SPHERES, across the module together with the gantry built in that can rotate it in any given way.
Host:Describe the gantry. What are you looking at?
Jose Benavides: When it comes to the gantry, think of, again, an arcade where you have this big hook that comes down.
Host:With the claw that comes down to grab the thing.
Jose Benavides: Yeah, exactly. A claw comes down, picks something up, and can move it any which way. Right?
Host:Yeah.
Jose Benavides: And then replace that claw with a gimbal where you have something that can rotate any which way.
Host:Okay.
Jose Benavides: And then inside that gimbal is SPHERES.
Host:But then it’s still SPHERES is the thing that controls where it goes.
Jose Benavides: With this gantry, the way we have it these days is it’s actively controlled. We actually have motors in the gimbal that will move it the way we want it to move.
Host:Okay.
Jose Benavides: Together with the gantry, actually. It’s actively controlled. There were initial ideas where this gantry, in fact, could be completely passive, and it’s the free-flyer doing the moving. And then we have very specialized sensors in there that would sense where it’s going, and then actively move it as if it’s in microgravity. So this whole gantry was trying to cancel out the gravity vector so that if the propulsion were moving a certain way, then the gantry would follow it along as if it were in microgravity.
This whole setup was actually first built and developed here at Ames for a project called PSA [Personal Satellite Assistant]. It was a previous incarnation of a free-flyer project developed here at NASA Ames. They first developed this whole lab setup to be able to do these kinds of simulations.
Host:And so you talked about the robotics competition that people participate in and some of the experiments. Go into a little detail. What is a typically kind of experiment that you would do on SPHERES that comes to mind?
Jose Benavides: It’s hard to say there’s anything typical considering the different kinds of research we’ve done using SPHERES. But one typical one might be one MIT is doing these days where they’re looking at, in space, automated docking of two satellites, or multiple satellites, where they’ve outfitted SPHERES with additional hardware that includes a rigid docking mechanism together with some cameras that aid the navigation of two of these units.
And so they put together and plan out what’s called a test session, the SPHERES test session, that we’ll conduct on the space station where the crew will pull out the SPHERES, pull out any addition hardware needed, do the assembly, program the SPHERES with software that was developed beforehand, push a few buttons, let them do what they need to do.
So there’s a test plan that calls out a series of test runs that we’ll do over the course of about two to five hours depending on the test session. And that’ll take up a good chunk of the crew’s day on ISS where they’ll be working with SPHERES doing these different test runs that we’ve outlined and trying to achieve the objectives that the researcher, in this case MIT, with looking at automated dockings. So they’ve got these rigid docks attached to SPHERES and they’ll try to get the two SPHERES to dock with each other.
Host:To match together.
Jose Benavides: Yeah.
Host:And that’s simulating what, ideally in the future, two satellites that are floating out in orbit.
Jose Benavides: Two satellites or two spacecraft, right?
Host:Wow.
Jose Benavides: One of the big objectives going to Mars is going to be sending things to Mars ahead of time, and then sending people later on. As people get there, they’re going to need to be docking with other things, different automated spacecraft with things may already need to be docking at Mars without our intervention. So that’s when you need to build in the intelligence to be able to dock with each other all by themselves when they’re, what, 10-minutes communication away, at Mars? They’re not as close as, say, ISS is here in orbit.
Host:I know the International Space Station they always love to say, “Working off the Earth, for the Earth.” But they’re doing things that you literally could not do here on Earth. Maybe in some simulations or something. But that kind of docking, you’re not going to want to test that on multimillion dollar satellites to figure, “Let’s just see if this works.” It’s very beneficial to have these prototypes floating in space where you can play around with that software and figure out how to do that.
Jose Benavides: That’s exactly right. Like I was saying, ISS is a risk-tolerant environment to be testing out these technologies that are eventually going to go to Mars or to other deep space destinations. And just another example of something you can only do on ISS is an investigation called Slosh where these researchers out of KSC [Kennedy Space Center] put up tanks of fluid, colored fluid, that would be sloshed around by two SPHERES units monitored by some HD cameras.
What they’re looking at is the movement of fluid in microgravity and trying to validate models that they already have that predict how these fluids can impart forces on, say, an upper stage rocket. Right? An upper stage rocket going up to space is going to have these huge tanks of fuel, and as they transition from, say, one stage to another stage, there’s these huge jolting forces. Right?
Host:Yeah.
Jose Benavides: And then you got the sloshing fuel in their tanks that may impart forces that take the rocket completely off course. Right?
Host:Yeah.
Jose Benavides: So they need to understand those forces. And they have software that predicts that.
Host:Yeah, to test it.
Jose Benavides: But very rarely, if ever before, have they been able to test these in real life, because we don’t have microgravity here on Earth.
Host:Yeah.
Jose Benavides: That’s just not something you can test here on the ground.
Host:Even in the airplanes that will go up high and then fall. You have seconds.
Jose Benavides: You have 20 seconds. Yeah, that’s really not enough. They did do that with some testing, but you just can’t get the kind of testing and fidelity you can as on ISS. So you got what’s basically a big fish tank of fluid being sloshed around by two SPHERES units and by crew, actually.
More recently, if you look at our website, you can see clips of a crew member taking two Slosh tanks, because they had actually sent up two at 40 percent fill and the other at 20 percent fill, duct-taped them together, and then sloshed around these tanks in very specific maneuvers in front of an HD camera to look at how this fluid moves around. And it’s some really cool clips you can see of how air bubbles might move around in there and how the fluid might move around in response to, say, a jolt on the side of the tank. Really cool. Just gushers of fluid you see spraying out in response to, say, a tap on the edge of the tank.
Host:Yeah.
Jose Benavides: And then these orbiting bubbles you see going on inside these tanks and really cool footage they got. I’d recommend anyone to go take a look at that.
Host:You had briefly mentioned Astrobee as what’s going to be following SPHERES.
Jose Benavides: Yeah, so Astrobee is a ground up redesign of a next generation free-flyer that’s to replace SPHERES here in 2018.
Host:Okay.
Jose Benavides: It’s more cubed in shape versus the orbital, spherical. It’s not quite a sphere. It’s actually more of a —
Host:Octagonal.
Jose Benavides: — dodecahedron, actually.
Host:An octagon, but in a sphere shape.
Jose Benavides: Right. Yeah, and I think someone once told me, it was technically an octadecahedron shape.
Host:All right. That just rolls of the tongue.
Jose Benavides: I had to practice that one a bit.
Host:Yeah.
Jose Benavides: But yeah, so SPHERES as its propulsion system uses compressed CO2 to move around.
Host:Okay.
Jose Benavides: So Astrobee is being designed to use a blower-based system, which is actually powered by batteries, which makes it far more automated, right? It has its own docking station where it can recharge its batteries and not need any external fuel to move around like SPHERES does. Because actually we filled those CO2 tanks here at Ames and send them up every time to replenish SPHERES.
Host:It’s like the vacuum cleaner. They’re like, “It goes out and vacuums and then redocks itself.”
Jose Benavides: Exactly. It wouldn’t be the first time that Astrobee is compared to the Roomba.
Host:The Roomba.
Jose Benavides: The Roomba of ISS.
Host:But it’s floating in ISS. It floats around, does its job, and goes back home at the end of the day.
Jose Benavides: Exactly. And so that’s a big goal of Astrobee is to automate these things that crew doesn’t have to do.
Host:Awesome.
Jose Benavides: Astrobee really has three objectives. First off, to replace SPHERES as a research platform to do any number of different research investigations. Second, to be a mobile camera platform. So ground controllers can control this thing on ISS and get different views and camera feeds from ISS without having to bother crew. And then as well as a mobile sensor platform.
So you can put any number of different sensors on this thing and it can do sensor sweeps all around ISS that crew doesn’t have to do. Because that’s actually something they do occasionally is do different kinds of sensor sweeps of ISS to measure radiation or CO2 or any number of other things, and this can be automated by a free-flyer like Astrobee. And so we’re trying to optimize crew time because that’s a very valuable thing on ISS.
Host:Cool. So for folks listening who want more information, I imagine NASA.gov/SPHERES is best place to get the SPHERES information. Is there a similar one for Astrobee yet or it’s incoming, I’m guessing?
Jose Benavides: It’s incoming. Actually if you do go to NASA.gov/Astrobee, there is a placeholder website right there.
Host:Okay, there’s a landing page.
Jose Benavides: There is a landing page. It’s got about a paragraph.
Host:“Coming soon.”
Jose Benavides: There’s about a paragraph of information there about Astrobee, but it’s slightly outdated here. In the days to come, we will be outfitting it with additional information. You actually find other resources and papers that have already been published through AIAA, though IEEE, that do outline a lot of the details of what Astrobee is going to be capable of. It’s a great source of information to learn about what’s Astrobee going to do, what it’s capable of, and what it can do in the future.
Host:And so in the short term of folks have questions for Jose, we are on Twitter @NASAAmes. We’re using the #NASASiliconValley. Go ahead and shoot us any kind of questions for Jose. We’ll loop back to him and get some responses for you.
Jose Benavides: Absolutely.
Host:Thanks for coming over.
Jose Benavides: Yeah, happy to be here.
[End]