Prague’s underground tunnels being mapped by robot dogs

SPOT robots in the underground tunnels of Kolektory Praha

The Faculty of Electrical Engineering at Prague’s Czech Technical University recently acquired two new assistants – agile dog-like machines with robotic arms that can navigate terrain and capture data – and is using them to create a digital 3D map of Prague’s underground tunnel network.

Spot, as its name suggests, is somewhat reminiscent of a bright yellow robotic dog. But this ‘robodog’ from US company Boston Dynamics can do a lot more than sit and come when called, as professor Tomáš Svoboda explains:

SPOT robots in the underground tunnels of Kolektory Praha | Photo: ČVUT

“It’s a quadruped robot with an integrated robotic arm, that’s essentially able to manipulate objects, even open and close doors. One of the unique features is that the arm, and more precisely the gripper, is equipped with sensors in the palm, so the robotic arm can perceive the environment – it can see, it has an RGB camera and also a depth sensor, so it can measure the distance to the object it is going to grasp.”

The two robots have already been put to use in Prague’s network of underground tunnels, managed by the firm Kolektory Praha. The network essentially contains the infrastructure of the city – gas pipes, electricity, sewage, and so on. The robots are being used to create a 3D map which will allow for a virtual tour of the system, accessible to the public. Tomáš Svoboda again:

“The network used to be accessible to the public but it’s not anymore, so as a replacement the company wanted a 3D model to allow people to see it virtually. More or less like you can walk through a map using Google Street view.”

SPOT robots in the underground tunnels of Kolektory Praha | Photo: ČVUT

This provided a unique opportunity for the computer scientists to test the four-legged robot's ability to move autonomously, without any human intervention, in an unfamiliar labyrinth-like environment, which is among the least explored areas of contemporary robotics.

“The ability to move, sense and plan in an unknown environment – this is something that the robots you can buy can’t do by themselves. You really need to do something more to allow them to move independently.”

SPOT s robotickou rukou připravuje digitální 3D mapu pražského podzemí

The researchers built on their experience in last year’s DARPA Subterranean Challenge in Kentucky, where competitors had to devise the most innovative and reliable way of transmitting information for their rescue robots in an environment without a communication infrastructure. Svoboda was part of the team that brought home silver.

“The underlying idea was pretty simple – bring your robots to an unknown underground space, let them in, and let the robots find objects of interest. The robots had 60 minutes to do that, and the team who found the most objects won.”

SPOT robots in the underground tunnels of Kolektory Praha | Photo: ČVUT

Thanks to its robotic arm, Spot can, for example, read labels on cables and thus find out where the cable leads, and is then able to enter the data onto the digital map. Tomáš Svoboda says that this is a project that has exciting possibilities for the future.

“This is looking to the future – creating a 3D map is one task the robot can do, but probably more importantly, in future the robots could do regular inspections of the network – checking everything is working correctly, that there are no leaks, they can measure the gas concentration, and so on.”

The ability of robots to create a communication infrastructure very quickly and efficiently will find application not only in underground spaces, but also, for example, during natural disasters, when the existing infrastructure is disrupted or has completely broken down.