HyQ is a quadruped robot that was developed at the Advanced Robotics Department of the Istituto Italiano di Tecnologia (IIT) (Semini, 2010 Semini, 2011). The robot weighs 80kg, is about 1 meter long and is constructed in aerospace-grade aluminum alloy and stainless steel. Each of its four legs has 3 joints that are actuated by hydraulic cylinders and motors. High-performance Fomula 1 valves are used to control each joint’s position and force. The force control in the legs enable a smooth interaction between the feet and the ground. Onboard cameras and laser range sensors create 3D maps of the surroundings. These maps are used by the robot control framework to plan its steps and avoid obstacles.
Since 2011, HyQ has been extensively tested in the laboratory on a custom, large-scale treadmill and in an outdoor test site. The robot has demonstrated various gaits and motions ranging from highly dynamic motions like running and jumping to careful walking over rough terrains. The robot uses a trotting gait with reflex and balancing skills on flat or moderately rough terrain. On more difficult terrains, the robot uses a crawling gait that allows to carefully put the foot on suitable spots. HyQ is one of very few robots in the world that have demonstrated such a wide repertoire of behaviors. A copy of HyQ has been sold to ETH Zurich in the summer of 2013. IIT and ETH Zurich have strong research collaborations in the fields of robot modelling, control and machine learning.
Legged robots are vehicles with the potential to replace humans in dangerous and dirty tasks where vehicles with wheels and tracks cannot go. Possible applications are disaster recovery (such as the clean-up of the Fukushima nuclear power plant), search and rescue, forestry technology and construction.