Transformer Meet Aquanaut, the Underwater · 8/20/2019  · support vessels and used for underwater manipulation. HMI wants to combine both of these modes into a single robot. It’s

Meet Aquanaut, the UnderwaterTransformer

Houston Mechatronics built a robot sub that transforms into askilled humanoid

By Evan Ackerman

Posted 25 Jul 2019 | 15:00 GMT

Photo: Ken Kiefer

The robot Aquanaut floats underwater during a test at NASA’s NeutralBuoyancy Laboratory.Into the Blue:

away from me, two astronauts are practicing for aspacewalk. I’m drifting weightlessly, in a silence broken only by my ownbreathing and the occasional update from Mission Control in my headset. Butthis isn’t the dark void of space. I’m in Houston, scuba diving in a massiveswimming to train astronauts for zero-gravityenvironments. And though it’s a thrill to watch the space-suited figures atwork, I didn’t come to see them. I’m here for a peek at Aquanaut, the brightorange robot that we’re sharing the pool with.

Just a short distance

pool that NASA uses

Aquanaut glides smoothly through the water like a miniature submarine. Atfirst, it doesn’t seem all that different from other unmanned underwatervehicles, or UUVs, equipped with sensors for gathering data and thrusters forpropulsion. Then, in what could be a scene from the movie , thetop part of the robot’s hull rises up from the base, exposing two massive armsthat unfold from either side. A wedge-shaped head packed full of sensorsrotates into place, and in a matter of seconds, the transformation is complete.The sleek submarine is now a half-humanoid robot, ready to get to work.

Transformers

represents a radical new design that its creators, at a startupcalled (HMI), hope will completely change subsearobotics. Conventional UUVs typically fit into two categories: torpedo-likefree-swimming submersibles, which are used for long-distance surveymissions, and boxy remotely operated machines, which are tethered tosupport vessels and used for underwater manipulation. HMI wants tocombine both of these modes into a single robot. It’s a bold approach that noone has attempted before.

AquanautHouston Mechatronics Inc.

Video: Evan Ackerman/IEEE Spectrum

The HMI engineers, who often joke that building a Transformer has been oneof their long-term career objectives, are convinced that it can be done.Aquanaut has been designed primarily for servicing subsea oil and gasinstallations. The companies that own and operate this infrastructure spendvast sums of money to inspect and maintain it. They rely on robotictechnologies that haven’t fundamentally changed in decades, largely becauseof the challenge of working in such an extreme environment. For HMI,however, that’s not a problem: Of its 75 employees, over two dozen used towork for NASA. Extreme environments are what they’re best at.

HMI cofounder and chief technology officer spent 14 yearsworking on advanced robotics projects at , inHouston. “I’ll grant you that getting into space is harder than gettingunderwater,” he says. “But space is a pristine environment. Underwater,things are extraordinarily dynamic. I haven’t decided yet whether it’s 10 timesharder or 50 times harder for robots working underwater than it is in space.”

Nic RadfordNASA’s Johnson Space Center

More Than Meets the Eye

Aquanaut is unique among unmanned underwater vehicles because it cantransform itself from a nimble submarine designed for long-distance cruisinginto a half-humanoid robot capable of carrying out complex manipulationtasks. Here’s how the transformation happens.

Illustrations: Houston Mechatronics

1. Aquanaut travels in streamlined submarine mode to a subsea worksite.

2. Once the robot arrives at the site, the top part of its hull rises up,exposing two massive arms and a wedge-shaped head.

3. The head, carrying stereo cameras, a 3D sensor, and a sonar system,rotates into place.

4. The robot unfolds its powerful arms, equipped with force sensors andclawlike grippers.

Radford and fellow cofounders and have raised morethan US $23 million in venture capital since starting HMI in 2014. Now, aftercountless design iterations, Aquanaut is finally coming together. Before takingto the open ocean, though, the robot needs to prove itself in more controlledconditions, and that means a swim in NASA’s pool.

Matt Ondler Reg Berka

of water and with a maximum depth of12 meters, NASA’s , or NBL, is large enough tocontain a full-scale mock-up of most of the , withroom to spare. Astronauts train for spacewalks at the NBL, coming just aboutas close to weightlessness as you can get here on the ground. On this late-March morning, HMI has taken over the north end of the facility to testAquanaut.

Holding 23.5 million litersNeutral Buoyancy Laboratory

International Space Station

Ten meters down and with two tanks of nitrox on my back, I try to keepmyself steady as I track the robot moving through the water. Aquanaut hasbeen in one piece for only about eight days now, but the testing is going well.The only hiccup is a communication glitch with the arms, but the HMI team isunfazed; they know there’s still a lot of work to do, and the robot will be backhere early tomorrow.

Radford tells me he enjoys the frenetic routine of running a startup, a sharpcontrast with the typical pace of a huge government agency like NASA. BeforeHMI, he spent five years as chief engineer of NASA’s program,developing a humanoid robot that flew to the International Space Station, andhe later led the development of , an even more sophisticatedhumanoid platform. In his office at HMI, small 3D-printed models ofAquanaut prototypes fit right in with wall art featuring Valkyrie and Marvel’sIron Man.

Robonaut

Valkyrie

“The type of skills that we have at NASA,” he says, “putting robots in remotelocations, and getting them to do useful work in austere data environments,best matched this big problem: working offshore.”

Most of what we see and hear about the offshore oil and gas industry involveswork done from platforms, where people conduct underwater drillingoperations from the surface. The platforms are the most visible part of theprocess, but there’s an enormous amount of complex infrastructure on theseabed as well.

Wellheads on the ocean floor are capped by metal assemblies used to controlthe flow of hydrocarbons to the surface. These structures, covered with pipes,valves, manifolds, and gauges, are so intricate they are commonly knownas . Some are the size of a four-story building.Christmas trees

Illustration: James Provost

In submarine mode, Aquanaut surveys and inspects oil and gasAquatic Handyman:

equipment deployed on the seabed. In humanoid mode, the robot uses its arms tograsp specialized tools and operate valves that control the flow of hydrocarbons to thesurface.

To perform routine maintenance on a wellhead, or to change the output of thewell, some of the valves on the tree have to be turned, and with wells in deepwater—below 300 meters, where divers normally don’t operate—the only wayto do that is with a robotic vehicle.

For decades, the established procedure for working on deepwater wells hasbeen to send out a remotely operated underwater vehicle, or , to the wellsite. But you can’t just send the ROV by itself—you also have to send a largesupport vessel packed with highly trained people to serve as a base ofoperations for the ROV, which has little or no autonomy and is tethered to thesurface for power and control. This gets very expensive very quickly, withtypical jobs costing tens to hundreds of thousands of dollars per day.

ROV

HMI’s plan is to cut the cord—cutting out most of the need for people alongwith it. Aquanaut will not require a tether or a support ship. It will travel insubmarine mode to its deepwater destination, where it’ll transform into itshumanoid form, unfolding its powerful arms. Each arm is equipped withforce-torque sensors and has eight axes of motion, similar to that of a humanarm. The arms on Aquanaut also have grippers capable of turning valves onthe subsea “trees” and even operating specialized maintenance tools that therobot carries with it in an internal payload bay.

Aquanaut will carry out tasks with human operators supervising but notdirectly controlling it. And once the job is finished, the robot willautonomously return home. Radford says the approach will make Aquanautboth faster to deploy and cheaper to operate than today’s ROVs. He estimatesthat costs could be well below half the market rate of a traditional operation.

The timing seems right. According to , a subsea technologypioneer who is currently chair of the of the

, based in Washington, D.C., the low price of oil over thepast several years has cut profits and led to increased competition among oilcompanies, driving the adoption of new technologies. Richards, whosefirm, , in Houston, supplies equipment to dozens ofsubsea companies—HMI among them—explains that while the industry willlikely be cautious about an innovation like Aquanaut, it will also be excited tosee what the robot can do.

Chuck Richards ROV Committee Marine

Technology Society

C.A. Richards & Associates

Richards explains that when the benefits of became evident after its introduction in the 1970s, the industry

was eager to embrace it, even though things were a little rough in thebeginning. “The oil companies were very helpful and patient with the ROVindustry as it matured,” he says, “and I think they’ll be the same way with amore autonomous vehicle.”

commercial ROVtechnology

Photos: Evan Ackerman

Engineers from Houston Mechatronics inspect Aquanaut’s head, wherethe robot’s main sensors are located, in preparation for an underwater test [top]. Whileconventional unmanned underwater vehicles require human operators to maneuverthem in real time, Aquanaut uses its sensing and computing systems to behave withgreater autonomy, able to carry out tasks with operators supervising but not directlycontrolling it [above].

Smart Sub:

over conventional ROVs depends on itsuntethered operation, and HMI had to solve several key problems to enablethat capability. The first is simply getting the robot to the offshore work sitewithout a large support vessel. While Aquanaut could be deployed from arelatively small boat, or even dropped out of a helicopter, the robot can travel

Aquanaut’s main advantage

more than 200 kilometers in submarine mode. Once it arrives, the robottransforms into ROV mode, with additional thrusters hidden inside the hullfolding out to make it more maneuverable.

The transformation itself was another major challenge—and a source of muchinternal debate. “We fought ourselves the whole way trying to prove that wedidn’t need to do it,” says , Aquanaut’s chief engineer, whoprior to HMI was the power lead on the rover at NASA. Butthe group eventually decided that the benefits outweighed the addedcomplexity: They were going to build their underwater Transformer.

Sandeep YayathiLunar Prospector

To enable Aquanaut to alter its shape so drastically, the robot is equippedwith four custom linear actuators that separate the top and bottom halves ofits body. Additional motors, also highly customized and housed in waterproofcases, drive the arms and the head. For power, Aquanaut uses a lithium-ionbattery similar to those found in electric cars. The full transformationcurrently takes just 30 seconds.

But perhaps none of these challenges is as significant as designing Aquanaut’scontrol system. Traditional ROVs have multiple live camera feeds, and humanoperators maneuver these vehicles with joysticks in real time. Without atether, the only way to communicate with Aquanaut is through an acousticmodem. This well-established technology has a range of a few tens ofkilometers underwater, at the price of high latency and very low bandwidth,in the neighborhood of a few kilobytes per second, at best. HMI plans to relyon small unmanned surface vessels to act as relays between the robot andcommunication satellites, and from there, Aquanaut can be controlled fromanywhere in the world. However, these constraints make direct humancontrol impractical, so Aquanaut will need to do as much as it can on its own.

“There’s a lot of autonomy that has to be built in,” Yayathi explains. “You trustthe robot to do a lot.”

HMI is planning on maintaining high-level supervisory control overAquanaut, while delegating most of the low-level decisions to the robot’spowerful onboard computers, which run the , orROS, a popular software platform for research and commercial robots. Usingthe sensor suite in the head, which includes stereo cameras, a structured lightsensor, and a sonar system, the robot constructs a detailed 3D rendering of itssurroundings. But instead of trying to send the entire 3D map back to theoperator, only very small and highly compressed subsections are transmitted,and the operator can then match them to an existing model of the structurethat Aquanaut is looking at.

Robot Operating System

The operator then sends simple commands, such as “Turn the valve at thesecoordinates 90 degrees clockwise.” The robot will autonomously decide howto grasp the valve and how much force to apply while turning, and it will sendback a confirmation when the task is complete. The operator is still directingthe robot’s actions, but in a way that doesn’t require steering the robot byhand, or a bandwidth-intensive live video feed.

HMI’s long-term plan is to sell Aquanaut interventions as a service. Usingsmall fleets of robots distributed across areas like the North Sea or off thecoast of California, oil and gas companies would simply need to request that agiven task be completed, and HMI would then schedule the nearest robot totake care of it. Radford says it takes about seven people to operate a singletraditional ROV. “We think we can invert that,” he says. “We think oneoperator could run seven Aquanauts.”

With a low-bandwidth connection and an operator only intermittently in theloop, there may be a greater risk of something going wrong, says

, a professor of mechanical engineering at the and director of the . “The uncertainty is there,” he says. “I’m worried about a

malfunction during an operation, which could have both financial andenvironmental consequences. Although the technology is exciting, they’regoing to need to prove that it’ll work.”

Matthew A.Franchek University ofHouston International Subsea Engineering ResearchInstitute

Photo: Ken Kiefer

To test Aquanaut under controlled conditions, Houston Mechatronicsbrought the robot to one of the biggest indoor pools in the world. NASA’s NeutralBuoyancy Laboratory, where astronauts train for zero-gravity environments, is largeenough to contain full-scale mock-ups of the main modules of the International SpaceStation [seen in the background].

Gone Swimming:

testing Aquanaut at the NBL, the teamcelebrates with a crawfish boil in the parking lot behind the HMI office,accompanied by improbable cans of , which came all the wayfrom a brewery in Brooklyn, N.Y. Stories about robotics at NASA flow asquickly as the beer, while I learn how to play cornhole and suck the juice outof crawfish heads.

After three exhausting days

Robot Fish IPA

A sense of relief that the testing went well transitions easily into excitementabout the future. Radford explains that the current version of Aquanaut isprimarily a demonstration and testing platform, designed for relativelyshallow water with a maximum operational depth of 300 meters. While thisversion could perform commercial operations in many parts of the world,HMI is already in the process of designing a scaled-up version that will beable to travel several hundred kilometers and reach depths of 3,000 meters,necessary for servicing areas like the Gulf of Mexico.

And of course, commercial operations aren’t the only things that HMI isexploring for Aquanaut. Radford couldn’t talk to me on the record about anypotential work with the U.S. Department of Defense, but in late 2018 theDefense Advanced Research Projects Agency announced a programcalled seeking proposals to “develop an undersea autonomous systemthat can navigate to and physically manipulate objects on the sea floor.”DARPA’s illustration accompanying the announcement features a streamlinedrobotic submarine with two arms, a concept that bodes well for a certainHouston company.

Angler

The party continues outside, but folks are already starting to trickle back totheir desks, intent on getting Aquanaut ready for its next NBL test. Its firstopen-water demonstration will likely take place at a naval technology exercisein Rhode Island in August. For a robot that was in pieces in March, it’s anaggressive timeline, but Radford is confident that his team can handle it.

“It’s fun to come to work on something that’s audacious,” he says. “We thinkthere’s a better, more cost-effective way to do work underwater. And we’regoing to prove it.”

This article appears in the August 2019 print issue as “The UnderwaterTransformer.”