Back in November, ESA astronaut Luca Parmitano made history by taking command of a rover from the International Space Station (ISS). As part of the Analog-1 experiments, this feat was made possible thanks to a “space internet” command infrastructure and a force-feedback control setup. This allowed Parmitano to remotely operate a rover 10,000 km (6,200 mi) away while orbiting Earth at a speed of 8 km/s (28,800 km/h; 17,900 mph).
These experiments, which are part of the ESA’s Multi-Purpose End-To-End Robotic Operation Network (METERON) program, took place in a hangar at Valkenburg in the Netherlands – near the ESA’s European Science Research and Technology Center (ESTEC). The first test, which happened on Nov. 18th, involved Parmitano guiding the rover through an obstacle course designed to look and feel like the surface of the Moon.
The tests validated the sophisticated control network as well as the controls, which provide astronauts with the sense of touch. For the second test, which took place on Nov. 25th, involved the rover navigating through a full-on simulated lunar environment, picking up and collecting rock samples. This test assessed the ability of a remotely-operated rover to conduct geological surveys on alien worlds.
As ESA engineer Kjetil Wormnes, who is leading the Analog-1 test campaign, said in a recent ESA press release:
“Imagine the robot as Luca’s avatar on Earth, providing him with both vision and touch. It was equipped with two cameras – one in the palm of its hand, the other in a manoeuvrable arm – to let Luca and the remotely-located scientists observe the environment and get a close-up on the rocks.”
Using the Sigma 7 force-feedback device (which gives the user six degrees of freedom) and a pair of monitors, Parmitano guided the rover through narrow pathways to reach three different sampling sites and select rocks for analysis. All the while, a team fo geological experts based at the European Astronaut Center (EAC) in Cologne, Germany, was in contact with him and advised him on which rocks were promising research targets.
This was the first time that this sort of technology has been used on the ISS to control a robot on the ground. It also built on a previous project conducted by the ESA designed to familiarize astronauts with geological studies. As Jessica Grenouilleau, METERON project lead at ESA’s Exploration Systems Group, indicated:
“We benefitted from Luca’s previous training through our Pangaea program, giving astronauts practical experience in geology. It helped tremendously in having an efficient discussion between the crew and the scientists.”
The two-way control link between the rover and the ISS was made possible thanks to communication satellites placed in geostationary orbit (GSO). These connected Parmitano to the EAC and on to the hangar where the test took place, and with a latency (or time lag) of just 0.8 seconds. Thanks to the revolutionary interface, Luca was able to feel the robot touching the ground or picking up a rock.
The METERON hardware and software used in these experiments was developed by the ESA’s Human Robot Interaction Laboratory, located in Noordwijk, The Netherlands. Support was provided by the German Aerospace Center’s (DLR) Institute for Robotics and Mechatronics, which was responsible for integrating the control software and optimizing the system’s feedback to take into account the time delay.
ESA robotic engineer Thomas Krueger, who heads the HRI Lab, explains:
“For this exploration scenario, involving a relatively short time delay, we’ve been able to combine the relative advantages of humans and robots: a human for their ability to deal with complex and unstructured environments and decision making, and a dexterous robot able to cope with harsh environments and to precisely execute its operator’s commands.
“By enhancing the operator experience with force-feedback and intuitive controls we can make previously impossible robotic control tasks feasible, and open up new methods of exploring space. We are now keen on analysing the data and feedback from Luca to see the details of how he performed, and find out where we can improve and prepare future exploration plans.”
The Analog-1 experiments are the latest in a series of progressively more challenging METERON human-robot test campaigns involving the ISS. The first force-feedback test (which involved one-degree of freedom) took place back in 2015 as part of the Haptics-1 experiment. This was followed in 2016 by the DLR’s Kontur-2 two-degrees of freedom experiment. All of these culminated in these latest, six-degrees of freedom experiments.
The next step will take place sometime next year and will involve an outdoor simulation in a Moon-like environment (located TBD at the moment). For this phase of testing, the rover will collect and examine local rocks samples in a scenario designed to resemble a full lunar surface mission as closely as possible.
When robotic explorers are sent to the Moon and Mars in the near future, METERON will let astronauts control them from orbital habitats – such as the Lunar Gateway and the Mars Base Camp – rather than having to send signals all the way from Earth. The technology will also allow for the exploration of inaccessible or potentially dangerous environments astronauts are not able to reach.
Be sure to check out this video of the latest Analog-1 test as well, courtesy of the ESA:
Further Reading: ESA