Swiss researchers have built an electrically actuated, walking, climbing, running four-legged robot that can handle difficult terrain.
The ‘dog’ robot is called StarlETH - its name pronounced ‘Starlet’ and featuring the acronym for the Swiss Federal Institute of Technology in Zurich (ETH).
It contains 12 actuators and almost 50 on-board sensors, allowing it to work either autonomously or via remote control. According to lead researcher Marco Hutter, “it’s meant to be a robot that can climb over obstacles, so being very versatile. It can run, it’s energetically efficient, so we want to have a robot that can go for multiple hours, and it should be in a size that one human operator can take it by himself, so not using a huge machinery to actually deploy it, but really take it somewhere and deploy it.”
Hutter, who is Assistant Professor for Robotics Systems at ETH, told Reuters that StarlETH contains integrated springs which help it store energy and release it with each bound. The team took inspiration from humans who mechanically recuperate much of their energy while running and sought to replicate this ability in their dog robot.
He said that quadruped models like StarlETH and those designed by Google’s Boston Dynamics will be particularly useful when it comes to locomotion in rough terrain such as search and rescue missions because they can adapt their gait and stepping location. “The big advantage of four legged systems is that we (they) can go on one side statically stable, which means that we’re (they’re) moving one foot at a time,” said Hutter. “So the robot is always stable, so you could just shut down all the motors and it will not fall over. So this is something you apply in a critical situation where you have terrain that you might not know if there is obstacles or something.”
He added: “We can also move dynamically stable, so the system itself just balances from a step-to-step basis and moves several legs at a time and you can even do this if I push it or pull it to the side. So it accordingly plans where to step to the ground, distributes the forces in appropriate way and balances out whatever disturbances they have and that of course works if I put something underneath the foot, so it senses that and accordingly plans where to step and how to resolve these problems that it has.”
The team says the medium-dog sized robot can act fully autonomously and contains three on-board computers, laser sensors, and cameras to perceive the environment. Its batteries allow it to run for more than one hour over a variety of terrain.
“One big advantage of our robot is the energy efficiency, where you are only using 220 watts and with two of those batteries we can walk about one hour,” said project engineer Remo Diethelm.
According to Hutter, StarlETH enjoys low power consumption, is easy to handle by a single trained operator, and is robust.
Although making their robot usable by non-roboticists will take further research and engineering, Hutter says eventually the successors of StarlETH could be used for a variety of real-world scenarios, such as large scale industrial environment inspections, bomb disposal, construction site transportation, search and rescue missions, and demining. He said one could also consider using such robots as security guards, waiters, butlers, and healthcare assistants - or simply for entertainment.
He said: “We are developing a new platform that has the same capabilities, the same skills, but which is way more ruggedised. So it can go outdoors under very harsh conditions - if you have water, if you have dust, and eventually working in an explosive environment - and for this we’re investing a significant engineering effort.”
The team, which is planning to set up a spin-off company, is currently taking part in the ARGOS (Autonomous Robot for Gas and Oil Sites) Challenge, a competition run by oil company Total to find a robot that can be used for oil exploration. The competition will see robots such as StarlETH undertaking autonomous inspection of off-shore oil and gas sites.