Suggested Searches

Robots Lend a Hand

Season 1Nov 13, 2018

Ashitey Trebi-Ollennu is in charge of the InSight mission’s robotic arm and hand. His work on space robots has led him to give a helping hand back home.

On a Mission podcast cover art

[0:03] (music)

[0:03] International Space Station robot CIMON:

“Should I contact the ground station?”

[0:08] Narrator: The International Space Station flies 250 miles above our heads, circling the Earth once every 90 minutes. The size of a football field, a lot of work goes into keeping this high-tech research center running. Astronauts on the space station have various robot helpers to lend them a hand.

On a Mission podcast cover art

One of those robots is actually a large arm on the outside of the station. The robot arm moves large equipment and performs other maintenance tasks. Because the robot arm was built by Canada’s Space Agency, it’s known as the Canadarm.

The NASA podcast, “Houston, We Have a Podcast,” talked about the Canadarm with Tim Braithwaite of the Canadian Space Agency, in 2017. He said it can be tricky having a robot arm that’s more than 50-feet long sticking out of the side of the space station.

[0:57] (“Houston, We Have a Podcast” excerpt)

Tim Braithwaite: You know, people often joke that these robots, gosh, they move so slowly.

Host: Right.

Tim Braithwaite: And that’s not to say that they couldn’t move faster, but if they did, there would be consequences. We have seen – you get modules moving really quickly and all of that momentum then has to be taken out at the other end of the motion.

Host: You’ve got to stop, yeah.

Tim Braithwaite: Otherwise the station’s orientation would have to adjust to that.

Host: You don’t do it right and you can fling – you can –

Tim Braithwaite: You could flip the station over.

[1:24] Narrator:As difficult and cool as it is to operate a giant robot arm in space, the technology has been helpful down here on Earth.

[1:32]] (“Houston, We Have a Podcast” excerpt)

Tim Braithwaite: It’s possible to do very, very fine, even microscopic surgery with versions of robotic arms. And the technology that that’s based on, as it turns out, is directly derived from the work that we’ve done on space station with Canadarm2.

And it’s not even just the physicality of it. It is the technology of controlling coordinated motion in very refined ways. Because we humans – if you reduce everything to a small enough scale, it’s actually difficult to control things that precisely. But the robot – if you gear everything down, the robot can really help you with that.

So if – your hands may not tremble, but when you’re at the micron level your hand’s really trembling and you’re not even aware of it. But that’s the level of control that they’re able to provide with these microscopic brain surgery robots. And that’s really helping people, and that’s exciting.

[2:31](intro music)

[3:03] Narrator:We’re “On a Mission,” a podcast of NASA’s Jet Propulsion Laboratory in Pasadena, California. I’m Leslie Mullen. This season is all about the InSight mission to Mars. Like the International Space Station, the InSight lander has a robotic arm. The robot arm is also tricky to use, and, as we’ll hear later, it’s led to joint benefits for folks back here on Earth. But today’s story is not just about InSight’s robot arm. It’s also about the person in charge of building it.

[3:33] Ashitey Trebi-Ollennu:My name is Ashitey Trebi-Ollennu, and I’m the Instrument Deployment Systems Lead on Insight.

[3:41] Narrator:Insight’s robotic arm is called the Instrument Deployment System because its job is to take scientific instruments off of the InSight lander, and put them on the ground. There are also cameras on the arm to help it see what it’s doing. Having this arm perform its task correctly is crucial, because if the instruments aren’t placed on the ground, InSight won’t be able to achieve its mission.

[4:02] Ashitey Trebi-Ollennu:The goal of Insight is to understand how terrestrial planets are formed. To understand how terrestrial planets are formed, you have to go and look deep beneath the surface. You have to look at the core of the planet. When I talk to kids they say, “Wow, you guys are going to dig all the way to the core?” And I say, “No, we’re just going to do an old-fashioned medical checkup.” Right? You go to your doctor, they have their stethoscope. They put it around your chest or your back or your lungs and then they read your pulse and then what do they do? They take your temperature. So Insight is going to do that. Insight is going to take the heartbeat of Mars. So for the doctor to be able to do that the doctor obviously needs a hand to grab his stethoscope or his thermometer. The doctor needs eyes to know where to place it and this is what the Instrument Deployment System is. The Instrument Deployment System on Insight is the hand of the doctor, the arm of the doctor, the fingers of the doctor, and the eyes of the doctor.

[4:58] (music)

[5:08] Narrator:Ashitey has come a long way to get to the Jet Propulsion Laboratory, also known as JPL. One of JPL’s other nicknames is “The Center of the Universe,” because JPL coordinates radio signals to and from all space missions beyond the Moon through connected antennas called the Deep Space Network. Ashitey came to the Center of the Universe from what could be considered the Center of the Earth. He grew up in Accra, Ghana, in Africa.

[5:35] Ashitey Trebi-Ollennu:The British Meridian or Zero Longitude rides right through Ghana. So Ghana is not in the Western Hemisphere or in the Eastern Hemisphere, it’s right in the middle and just above the equator. Ghana is a cross between… honestly, a country in the Caribbean and the Amazon rainforest. Very beautiful long white beaches along the Atlantic Coast, and the castles and forts in Ghana are older than what you find in the United States. There are castles and forts from the Danish, from the Portuguese, from the Dutch every country because Ghana used to be the Gold Coast because there was gold all over. And as you move from the coast to the inland you find rainforest. So you move from beautiful coast beaches to rainforest, from rainforest to savannah because as you get further north, you’re approaching the Sahara Desert. So it covers it all.

So one of my uncles, Justice Nii Amaa Ollennu, he became acting president a few times and was the Speaker of Parliament during the second Republic of Ghana.

[6:39](UCTV History news report)

“To the people of the Gold Coast, there came last week a day that will always be remembered in their history. For here, in what’s been a British colony for more than a century, nearly a million people went to the polls in their first general election. The main issue in the election lay between those who want self-government sometime in the future, and those who want it now, like the Convention People’s Party, the CPP. Their leader, Kwame Nkrumah, spent election day in jail, serving a sentence for incitement and sedition.”

[7:07] Ashitey Trebi-Ollennu:So when Ghana gained independence from the British in 1957, the Queen was the head of state and we had a Prime Minister: Kwame Nkrumah. So during the transition, Ghana became a republic three years after that.

[7:18] (BBC Four news report)

Newsreader: “Leaders from East and West came to Accra to see the hand-over. Vice President Nixon represented the United States. He arrived with a delegation that included civil rights leader Martin Luther King.”

Martin Luther King, Jr.: “A new order is coming into being and an old order is passing away. It seems to me that this is fit testimony to the fact that eventually, the forces of justice triumph in the universe, and somehow, the universe itself is on the side of freedom and justice.”

[8:02] Ashitey Trebi-Ollennu:Kwame Nkrumah became the President and during those times we had the Cold War. We had the East-West struggle and the government at that time was leaning a little bit East and that was the first coup d’état in Africa, to overthrow the government to replace with a military government.

[8:17](News clip: A&E classroom)

“The redeemer, the savior, is now the fallen idol. Newspaper headlines report the spectacular overthrow of Kwame Nkrumah. And jubilant crowds celebrate his downfall in the streets of Accra.”

[8:33] Ashitey Trebi-Ollennu:And then subsequently there were elections for the second republic. And my uncle’s party won. And my uncle became the Speaker of Parliament for a while. Then he became Acting President during the absence of the President a few times. He was a very well-known justice. If we go into the history of Ghana laws, most cases will cite his cases, or if you go to law school in Ghana, you see a lot of cases that is based on precedence of what he has done, so he’s very prominent in that sense.

When I was a teenager, I spent a lot of time with my uncle. He had already retired by then, but he was writing. He wrote a lot of the laws of the country in terms of inheritance, so he changed the inheritance laws so that females could inherit from their parents. Before, females were banned from inheriting from their parents.

I was brought up in a family that took civic responsibility very seriously. We would volunteer to do things to just help other people in need, and we had a volunteer organization. My dad was an economist. My mom was teacher. My dad formed associations to help towns to mobilize themselves to be able to solve their own problems. Everybody in my family leaned a lot more towards the art and law and I leaned more towards engineering, so I’m kind of a standout.

When I was growing up, our house was very close to the international airport, so I always saw planes coming in and out and I was always fascinated by them. So I usually knew the schedule of all the planes. So back then we had British Caledonian and now British Airways, and I knew Pan Am when Pan Am was going to land and when it was going to take off. I just memorized all the different schedules for the planes that I could tell the different types of planes. Boeing 747, Boeing 737, and all the Aeroflot and all the Russian planes as well. So I had a Pan Am little model because I think my dad flew Pan Am and then they gave him the model.

I always wanted to go to England to do my aerospace degree. When I was in secondary school probably about 12 to 14 years old, I used to write to British Aerospace and they’d send me posters of the Harrier. I was very fascinated by the Harrier aircraft. That’s an aircraft that could take off vertically and it lands vertically. It’s one of the cool British inventions so I got a lot of posters of it in my bedroom and I used to read about it. I used to write those days you write letters, right? and they’d send you a whole brochure about it. I was very fascinated by that kind of technology.

[11:06] Narrator:Ashitey’s dream to study aerospace in England came true, and he traveled far from his home country. But in some ways, England felt very familiar.

[11:15] Ashitey Trebi-Ollennu: Culturally, it wasn’t a shock because Ghana was a former British colony. The language of instruction in school was English. That’s the official language of Ghana, is English. There are about 14 other dialects, at least. But English is the medium of communication. So most of the TV shows that we watched were all from England. So in that sense it wasn’t different. And in terms of studying, it wasn’t different because we had the same syllabus. I took my Advanced Level from the University of London, so we do the same test. But obviously, the weather was different. You have low clouds, grey, what the British call “bad light.” (laughs) And you got to use the train; you have to use the metro. So there were things that were quite different in that sense.

[11:56] (London Underground announcement)

“Please mind the gap between the train and the platform.”

[12:01] Ashitey Trebi-Ollennu:So I went to university at Queen Mary College, University of London. I was very much interested in those days in what we used to call “the glass cockpit.” That is where we automate the cockpit. It’s all touchscreen and it’s all computerized. So I majored in avionics and then went straight to my Ph.D. to do controls, basically automation for missiles and autopilots and vehicles, underwater vehicles.

[12:25] Narrator:After getting his PhD, Ashitey came to the United States, to pursue his interest in robotics at Carnegie Mellon University.

[12:33] Ashitey Trebi-Ollennu:When I arrived at the U.S. at Carnegie Mellon University in Pittsburgh, I applied control techniques to a DARPA project that was basically multiple autonomous vehicles doing surveillance and recognizance for, those days it was the Bosnian war where they wanted to put these robots on the streets to avoid snipers, to be able to figure out where the snipers are. We developed that technology for a while. So I joined JPL in 1999, to work on multi-robot systems.

[13:00] (music)

[13:07] Ashitey Trebi-Ollennu:I’ve always been interested in space. When I was a kid, I was always fascinated by the Moon, so I usually stand on my porch and look at the different phases of the Moon throughout the year. And I was fortunate that I lived very close to the center of Accra where we have most of the embassies like the U.S. Embassy and the British Consulate and things like that. And they usually have a weekly newsreel that you can go in and watch the news from the “Voice of America” or from the BBC. So I saw a little bit about the Moon landings and documentaries.

[13:49](BBC “Panorama” coverage of Apollo 11)

“Good evening. The first men on the Moon lifted off on the first stage of their journey home an hour and 6 minutes ago. The Stars and Stripes flies proudly now over the Sea of Tranquility. A new chapter in human history has opened. The race for the Moon is over. Man’s probe into the universe has begun.

[14:10] Ashitey Trebi-Ollennu:JPL and NASA were interested in what they call “precursor missions.” So these are missions to Mars where we will send robots to build infrastructure for humans. Because the human time is very precious, right, so when they get there they want them to start doing exploration and collecting rocks and doing all that stuff. They don’t want them to build an infrastructure. So I joined JPL and I worked with a team of people and we started doing robots transporting very long loads. So you have a payload of about two to three meters and you have very small robots. You want them to pick them up and transport them to the deployment site, so we did a lot of these tests and we were very, very successful at it. Then obviously, NASA goes through transitions and the precursor mission kind of fell off the rail.

[14:52] Narrator:Although his first NASA project didn’t work out, over the years Ashitey has been able to send his robots to Mars four times. One of the missions he worked on, the Mars Phoenix lander, also had a robot arm. The arm had a big scoop at the end of it, to dig into the soil near the Martian North Pole, and then transfer that soil to instruments on the lander for testing. Ashitey was part of the team operating the arm.

[15:17] Ashitey Trebi-Ollennu:We’re going to do experimentation to dig and look at icy soil materials and then try to figure the soil composition. We’re very fortunate to be one of five people to be able to dig ice on another planet. We call ourselves “the gravediggers on Mars.”

So it was an exciting mission because the lander was going to die because we only had a year, because winter was coming in, right? So it was a race against time. So we landed and we had to work very fast. We had a lot of excitement because we know from orbital data that if we dig five centimeters were going to see ice, and lo and behold, we could see the icy material. It was a lot of fun and it was really exciting. A lot of discovery, a lot of challenges. As you know from actual exploration, not everything works, so we had challenges with our instrument, but we were able to persevere and fight it to the very end.

[16:09] Narrator:Many parts for InSight are the same as for Phoenix, but the arm for InSight actually comes from a mission called Mars Surveyor 2001, also known as Mars ’01.

[16:19] Ashitey Trebi-Ollennu:Mars ’01 was canceled, and they had a flight robotic arm sitting in the warehouse. I think of the arm as a pre-used car, but not that used. (laughs)

But the challenge here is that Mars ’01 was built on the NASA philosophy of “Faster, Better, Cheaper,” so that means you skipped a few steps to make things a little bit faster and to make things a little bit cheaper. And Insight is working in the new regime where we’re more rigorous in our processes. So the challenge is, how do you take something from a different era and make it compliant to the current system?

So there’s a few things we’ve changed on the arm for InSight. First of all, the lengths of the arm which are the upper arm and forearm tubes, we’ve replaced them with titanium, they used to be composite. We’ve also taken the actuators and cleaned them up and re-lubricated them. We’ve replaced the camera. We’ve put in a new scoop and then we’ve put in the most important thing, the grapple.

[17:20] Narrator:The robot arm for Mars ’01 had been designed to pick up a little toaster-oven-sized rover off the lander and place it on the ground. InSight’s robot arm has a similar task : it will pick up three scientific instruments off the lander and place them on the ground. Despite the seeming simplicity of this task, robots actually aren’t that good at picking things up. In fact, developing a robot hand has been one of the biggest challenges in robotics. Robotic designers have made hands in different ways, from more human-looking hands with a palm and fingers, to grippers that look like various tools. In the 2017 Amazon Robotics Challenge, robots had to sort items like bottles, toys, and sponges and place them in boxes. The winning team had a hand resembling the “claw crane” arcade game.

(claw crane sound effect)

[18:08] Narrator:The hand on the end of InSight’s arm, called the grapple, also resembles a claw crane.

[18:14] Ashitey Trebi-Ollennu:The grapple is something that you see in the arcade where you take your kids and then they’re trying to pick those teddy bears, and they usually fall out of the grapple. This grapple wouldn’t do that. This grapple is really good. Once you pick up something it’s not going to let go until you tell it explicitly to let it go. I don’t think the people in the arcade would like our grapple. They’re not going to make any money.

[18:34] Narrator: The grapple’s five-fingered “hand” opens by melting wax: the same kind of wax used in candles and crayons. Nick Haddad, one of the engineers who worked on the grapple, explains.

[18:44] Nick Haddad: It uses a wax actuator to open the fingers. It’s actually a thoroughly proven technology. It’s used in space applications like the InSight grapple, but it’s also used for decades in things like our car thermostats and our appliances at home. It uses a heater to melt some wax inside of a little housing. And when this wax melts, it expands. And it develops this hydraulic pressure. And that pressure pushes out a rod, which we use to actuate our mechanism.

[19:11] Narrator:To get the fingers to close again, you just need to switch off the heater. As the wax cools, it contracts and causes the fingers to tighten their grip. The first instrument the robot arm and grapple will need to place on the ground is a seismometer, which will be used to detect marsquakes. Here’s Ashitey again:

[19:30] Ashitey Trebi-Ollennu:The seismometer is tethered to the lander. We first image where we land. The scientists can pick exactly where they want put this instrument to get the right measurement, just like a doctor does. A doctor tries to put it on your heart or your lungs somewhere to get the right information. Once they’ve done that, my team, with the rest of the mission operations team, they’ll set off sequences to pick up the seismometer, peel the tether that links it to the lander to send data and power back and forth, and put it on the surface.

The seismometer is very, very sensitive. If a butterfly lands on it and flaps its wings it’s going to detect it. So the winds of Mars and the temperature fluctuations would swamp the signal of the sensors. So what we have is what we call the “Wind and Thermal Shield.” So this Wind and Thermal Shield is a big dish that we’re going to pick up and then put it on top of the seismometer.

Once we’ve done with that, we have to take the temperature of Mars. We have an instrument a mole, which is basically a self-hammering nail that will hammer itself up to five meters into the ground. And behind it it’s got a tether with thermocouples that will take the temperature of Mars for a year. Combining these two seismometer and heat flow we can tell you something about the core of Mars, the materials of the core, the mantle, and the crust.

We’re doing all this blindfolded, hundreds of millions of miles away. So the other way you can think of this deployment is like you have a fish pole with an instrument at the end, and you want to put it within the location.

[21:02] Narrator: Growing up in Ghana, Ashitey never dreamed someday he’d be operating robots on Mars. His work for NASA and JPL has led him to also become involved with FIRST, an organization which holds robotics competitions for students.

[21:15] Ashitey Trebi-Ollennu:Two years after I joined JPL, we started supporting FIRST Robotics in Southern California. So I participated for two or three years and I could see how that was kind of helpful to middle school and high school kids. So I took the same concept and I went to Ghana and I formed the Ghana Robotics Academy Foundation, with the help of the State Department and the U.S. Embassy in Ghana, and it’s based on FIRST. And the goal there is to connect science theory to practice.

Most people in the developing world, or in very low socioeconomic status, don’t have the necessary resources to be able to do experimentation. They see science as very remote. They don’t see it in their everyday life.

So what we’ve done is there are robotics clubs in most of the schools now. We also allow private teams, so if you’re a religious organization [you can form a team].

[22:06](TV3 Ghana news report)

“Some of these students may well be the future of African-led missions in space. But a step at a time. First, building robots out of LEGO blocks and programming them to navigate through a maze using light and sound. It’s a chance for them to connect scientific theory with hands-on learning to fix real problems.”

[22:24] Ashitey Trebi-Ollennu:So we’ve been going for about seven years now. We started in 2011. And every region of Ghana has a club or have schools and we have competitions throughout. We’ve been able to send teams to the World Robotics Olympiad, to the Robofest, and to several many international events that have done very well.

Also, we usually encourage a lot of girls. So we have more girls’ teams than boys’ teams. We have more girls’ teams winning the competition.

You know, you go and talk to kids, kids that are not really interested in school and not interested in science. As soon as they start building, they start connecting theory to practice. Some light bulb goes off in their head and their grades improve. And we’ve seen that from the statistics that as kids participate their rate of engagement goes high in class and their attention span. Because they can see the usefulness of what you’re doing in class, and not having that connection I think is a disservice to a lot of kids.

We try to take things that you’re learning in school – a very simple one is the equation of a line. Most people say, “Why do I need an equation of the line?” And we take that and we can show them you can build a robot that can follow a line, and this is what is done in Amazon warehouses where the robots follow the lines. and then pick up the thing and then we can show them, “Look, this is what people are doing in real life.” This is how you can take the theory you’re learning and use it to develop new technologies to make things work, and help your society.

[23:52] Narrator: Next time, On a Mission:

[23:54] Cody Colley:The spacecraft is set to turn off at a certain time. So we got messages down from Wall-E saying, “Yeah, I’m leaking; I’m leaking; I’ve got to go now; I’ll talk to you in eight hours.” It’s like, “Oh, man.”

[24:09] Narrator:If you like this podcast, please subscribe, rate us on your favorite podcast platform, and share us on Facebook, Instagram, and Twitter. We’re “On a Mission,” a podcast of NASA’s Jet Propulsion Laboratory.

(end music: finis)

[run time: 24:26]