Moog’s Miniature Servo Valves Control the New Quadruped Robot of the Istituto Italiano di Tecnologia (IIT)

12 January 2015

Hydraulic Technology Selected over Electric for Greater Performance, Strength and Control of the Legs of the Advanced HyQ Robot. A team of researchers from the Istituto Italiano di Tecnologia (IIT), based in Genova, Italy, selected Moog Industrial Group, a worldwide designer, manufacturer and integrator of precision control components and systems, to provide a miniature servo valve to optimize control of the legs of a new quadruped robot. The robot called HyQ or Hydraulically actuated Quadruped was created to help humans in emergency situations and during search and rescue operations in dangerous areas.

“The project, started in 2007, represents an important innovation in the field of bio-inspired robotics and has the ambitious goal of creating a highly versatile Robot, capable of moving around on its four legs with agility, even over rough terrains, overcoming the obvious limitations of tracked robots being used up to now,” explains Claudio Semini, project leader engineer of the Advanced Robotics Department of the Istituto Italiano di Tecnologia. “For this reason we chose the hydraulic solution for HyQ over the electric one, as it guarantees us higher performance and power, strength and improved control of the legs.”

The design of the “actively compliant” legs was a key element in the development of HyQbecause the miniature valve allowed for the rapid modification of the hydraulic flow to the moving parts, enabling modulation of the rigidity/elasticity of the limbs and absorbing the shock of impact when the legs hit the ground thereby preventing damage to the central body. Moog’s Miniature Valves (E024-LA) fully satisfied the researchers’ need for compact size hydraulic servo valves capable of guaranteeing high performance oil flow control and maximum strength. The E024 series was originally developed for use on F1 automobiles and its key advantage in motorsport applications is the high ‘power density’ of the technology in an ultra-light weight design, weighing just 92 g (3.24 oz.).

HyQ represents a complex engineering project made up of mechanical, hydraulic and IT elements and the results to date have been called remarkable by experts in the industry. This robot can jump or walk on a rocky trail or along a corridor with V-shaped slanted sides, run at different speeds (up to 2 m/s/ 6.56 ft/s) and adjust its speed in response to  different environments. The installation of a perception system and an inertial measurement unit (IMU), enable the robot to plan its own movements, based on a map of the surrounding environment, and correct its steps, in real time, while always maintaining its predetermined posture. HyQ is also one of the few robots capable of doing the “flying trot”, where all four legs lift off the ground. See an example video at

Daniele Masciocchi, sales manager of Moog Italia commented:“Our ongoing cooperation with the Research Team of the IIT for the development of the Quadruped Robot, represents an important best practice, as an indication of Moog’s ability to create specific and highly innovative motion control solutions, such as miniaturized systems and components used in various types of industries from robots to Formula 1.”

Claudio Semini, project leader engineer of the Advanced Robotics department of the Istituto Italiano di Tecnologia says: “We are very proud of the enormous progress we have made, but our work is not finished yet. HyQ currently is almost one metre long (3.28 ft) and weighs about 80 kg (17.63 lbs), and we are still working on the power source system, currently managed through an external unit, in an effort to mount it directly on board, even though it will increase the weight. We are trying to set up new partnerships with companies, like Moog, that are capable of meeting our needs for components that are smaller and lighter, yet high performance.”

 For more information on the robot HyQ please visit

 About Istituto Italiano di Tecnologia

Istituto Italiano di Tecnologia is a private Foundation jointly established by the Ministry of Education, University and Research and the Ministry of Economy and Finance. Its aim is to promote excellence in both basic and applied research and to facilitate the development of economy at the national level.  The number of IIT’s staff people is about 1250. The scientific area accounts for about 85% of personnel, 44% of which is from abroad: 27% are scientists from more than 50 countries and 17% are Italian researchers who have come back to Italy after a professional experience abroad.IIT has produced about 5000 publications and 140 inventions resulting in 301 patent applications. In Genoa, departments include: robotics (“Robotics, Brain and Cognitive Sciences” and “Advanced Robotics”), life sciences (“Neuroscience and Brain Technologies” and “Drug Discovery and Development”) and “Nanochemistry”, “Nanophysics”, “Pattern Analysis & Computer Vision” and “iCub” facilities.  Since 2009 scientific activity has been further supported by 10 subsidiary research centers located elsewhere in Italy (Turin, Milan, Trento, Parma, Rome, Pisa, Naples, Lecce) ITT is committed to developing the platforms foreseen by the 2012-2014 scientific plan.


 Hydraulically actuated Quadruped


Caption: Quadruped. Courtesy of: Agnese Abrusci (IIT)