Når højteknologi går under jorden

ANYmal, en robot udviklet på ETH, kan se og høre, og endda åbne døre. Et internationalt forskerhold arbejder nu på at sikre, at robotten kan fungere under ekstreme forhold - en mission, der tager dem til labyrinten af ​​afløb og tunneler under Zürich.

To mænd løfter den 30 kilo tunge højteknologiske maskine og sænker den ned i den mørke skakt ved hjælp af et reb. Vi tager reflekterende overalls på, byt vores sko ud med lårhøje gummistøvler og sæt dem godt fast til vores outfits. Så kommer en hjelm, en lommelygte og engangshandsker til hver af os. Fuldt udstyret, vi begynder vores nedstigning, følger trinene ned ad skaktens væg en efter en, indtil vi når Zürichs kloaksystem, fire meter under overfladen.

På denne varme efterårsdag udfører et team af forskere tests under jorden. Deres mål er at afgøre, om ANYmal – en robot udviklet i fællesskab af Robotic Systems Lab og ANYbotics, en ETH-spin-off – kunne en dag blive indsat i kloaksystemer. Det kan bruges, for eksempel, at hjælpe ansatte i byen Zürich, som regelmæssigt må gå eller kravle gennem de omkring 100 kilometer tilgængelige skakter og afløb under byen, og hvis opgave det er at tjekke vægge og gulve for skader. Dette arbejde udgør ikke kun en sundhedsrisiko, men er også potentielt dødelig, givet, at afløbene kan fyldes op med vand meget hurtigt uden varsel. En anden fordel ved robotter i et sådant miljø er, at de kunne operere i smalle kloakker, som ikke kan tilgås med den teknologi, der bruges i dag.

Indledende testkørsel

Forskerne placerer robotten oprejst i bunden af ​​skaftet. Den er omkring 50 cm høj og har fire leddelte ben samt noget, der ligner et hoved, der består af et kamera og forskellige sensorer.

Peter Fankhauser, medstifter af ETH-spin-offen, der kommercialiserer ANYmal, sender sine kolleger i radio på overfladen, som er ansvarlige for at koordinere testen og sende kommandoer til robotten. Fankhauser drejer derefter med et joystick, og robotten suser frem. Da dette er den første test i ukendt terræn, han tager delvis kontrol over robotten, selvom den er i stand til at bevæge sig autonomt. "Det er en forholdsregel, " siger Fankhauser, "Bare fordi noget fungerer i laboratoriet, betyder det ikke altid, at det gør det i den virkelige verden." Trods alt, forholdene under jorden er ikke, hvad robotten er vant til:kammeret er vådt og glat, med lavere temperaturer og højere luftfugtighed end i laboratoriet. Hvad mere er, det er meget, meget mørk.

"Det er svært at skelne meget hernede, " siger Fankhauser, næsten med en antydning af resignation i stemmen, mens robotten bevæger sig i et langsomt tempo gennem den cirka tre meter høje og fem meter brede tunnel. Robotten udsender en ensartet elektromekanisk lyd – en slags rytmisk susen – der blander sig med lyden af ​​brusende vand, der kommer fra hovedkloakken i nærheden. Vi er i en ret stor overløbskloak med kun et dryp vand i. I betragtning af at robotten er på sin første prøvekørsel fire meter under jordoverfladen, forskerne har taget den forholdsregel at undgå store mængder vand.

Finder vej i mørket

Målet med det treårige forskningsprojekt med titlen THING (sub-Terranean Haptic InvestiGator) er at designe robotter, der kan bevæge sig rundt på egen hånd og er bedre i stand til at identificere deres omgivelser. Robotter bruger generelt 3-D-kameraer og lasersensorer til orientering. Men sådanne enheder kan ikke fungere under ugunstige forhold - såsom når jordoverfladen er våd eller luften fuld af støv. Derfor anser forskerne øget haptisk perception – orientering ved berøring – for at være en mulig løsning. Projektet har samlet ETH-forskere med kolleger fra universiteter i Edinburgh, Pisa, Oxford og Poznań.

Alle disse institutioner eksperimenterer med ANYmal robotter, og projektdeltagerne fra de forskellige lokationer mødes med jævne mellemrum. Ud over testene i kloaksystemet, næste år vil forskerne indsætte robotten i en polsk kobbermine. Det vil afgøre, om det kan fungere i et helt andet mikroklima, en karakteriseret ved varm, støvet luft og grusoverflader. ETH er repræsenteret i projektet af Laboratory for Robotic Systems ledet af professor Marco Hutter, som har forsket i robotter med ben i mange år. Han modtog støtte fra ETH kort efter at have påbegyndt denne forskning i form af et ESOP-stipendium og et Pioneer-stipendium.

Et af de centrale spørgsmål på denne første testdag er, om robotten overhovedet kan finde rundt i kloaksystemets mørke. I første omgang, to hjælpere med store LED-lamper oplyser omgivelserne, så vi tydeligt kan se, hvad der foregår. Derefter, Fankhauser asks the helpers to turn off the lamps and radios his colleagues on the surface to tell the robot to use its own lights. The robot's sense of touch isn't the only thing that helps it find its way in the dark, as Hutter explains:"The robot uses laser sensors and cameras to scan its surroundings. By identifying irregularities in the surface of the concrete, it can determine where it is at any given moment."

All that can be seen in the darkness now are the small round LEDs in the robot's "head". The atmosphere is other-worldly:the darkness, the sound of rushing water, the electromechanical whirring, the robot's LED eyes. Then someone breaks the eerie silence momentarily with a droll comment:"Its eyes are a bit like a Rottweiler."

Underground and offshore

Researchers at ETH have been working on quadrupedal robots since 2009. The first ANYmal prototype was completed in 2015 and, one year later, ETH established the spin-off ANYbotics. The fledgling company's mission is to make robots deployable in all types of terrain so that they can be used in a wide range of practical applications. The company's slogan is "Let Robots Go Anywhere". On-site tests are carried out two or three times a month. For eksempel, Fankhauser and some members of his team recently headed to an offshore platform in the middle of the North Sea. The hope is that robots could one day perform inspections on such platforms. On its pilot run at least, ANYmal autonomously completed several inspection routes with flying colours.

After almost ten years of research, there's a lot ANYmal can do. It can not only walk autonomously, but also boasts the sensory capabilities of sight, hearing and touch. These enable it, for eksempel, to read the air pressure display on a machine, identify sounds and recognise objects – for example to determine whether or not a fire extinguisher is in the right place. The robot can even perform certain manual tasks on its own. Equipped with an additional gripping arm, it can open doors, dispose of refuse or press a lift button. It also delivers data that is more precise than our own eyes, ears and noses can perceive. It can identify the ambient temperature and detect the presence of gases in the air. Its latest trick is recognising the composition of the ground beneath it. "Some of its powers are superhuman, " says Fankhauser.

Despite the lack of light in the sewer, the robot seems to be finding its way quite well, plodding through the shallow channel at a leisurely pace. When the high-tech machine reaches a 20-centimetre-high ledge in a dry side arm of the sewer, Fankhauser brings it to a halt with a flick of the joystick. I første omgang, he is reluctant to give the robot the command to climb over the ledge. Although it has easily mastered this manoeuvre in laboratory conditions, down here it is a risky undertaking. "It's an expensive machine, " says Fankhauser. But he gives it a try anyway. ANYmal doesn't manage it at its first attempt. It stops at the ledge like a horse balking at a jump. "Default, start again, " radios Fankhauser. Now the robot elegantly places one leg after another over the ledge.

Huge data volumes

While Fankhauser and Hutter watch the robot continue on its patrol for a while, I return to the surface via the entry shaft. Sitting on a bench under a white canopy, their eyes firmly fixed on a laptop, are two assistants from ETH.

A generator is buzzing and a router is blinking – and many a cyclist passing by along the main road looks on in bemusement at the hubbub around the open manhole at the side of the road. Looking over the researchers' shoulders, I can see an almost constant stream of data flickering across the screen. And thanks to state-of-the-art 3-D and laser technologies, live images constantly transmitted by the robot from underground are visible on a separate monitor.

When Fankhauser radios from below that he wants the robot to touch the wall of the sewer with one of its legs, the two assistants have their work cut out for them. The software they are using has not been programmed for this. They respond quickly, imidlertid, taking an algorithm originally programmed to teach ANYmal to shake hands. But to make sure the robot doesn't hit the wall with force, the researchers have to adapt the parameters. I dette tilfælde, the problem is the angle at which the robot is to raise its leg. One of the assistants types in 100 and then gradually ratchets up the number. At 180 the perfect level is reached and the robot's manoeuvre is successful.

Fankhauser and Hutter emerge from the cool, humid environment of the sewerage system into the warm autumn sunshine. They slowly begin to relax as they take off their reflective overalls. "The robot was in non-stop operation and collected a lot of data, " says Fankhauser as he undoes his high rubber boots and removes his protective clothing. Professor Hutter is satisfied, too:"All the teams will be taking home a huge volume of data to incorporate in their research." They are now one step closer to their goal of delivering a robot that can function properly in challenging conditions underground. But their work is far from finished. The robot recorded 500, 000 measurements per second over the course of the day. "That's enough data to keep us busy for six months, " says Fankhauser with a laugh.