The Secret Behind Husco’s Perfect Circle: Electro-Hydraulic Technology

In 2017, Husco engineers were working on a complex solution for the off-highway market. The goal was to create an electro-hydraulic machine control system to turn an existing pilot operated hydraulic machine into a semi-autonomous, digitally-controlled one.

“The challenge for us was how to bring advanced electro-hydraulic performance to a machine that has been developed for humans, not digital operation” Simon Yardley, Husco Director of Business Development and Corporate Marketing.

This was much more than just a new product offering. Husco wanted to create a turn-key solution for existing off-highway equipment that allowed mobile machine customers to upgrade – not replace – machines in the field with this new technology. In addition, the technology needed to be safe and provide flexibility to have autonomous, augmented, or remote digital control of the machine.

Giotto’s Perfect Circle

There is a legend that Giotto, a famous Italian painter and architect born in the 13th century, drew a perfect circle with a single stroke of his hand to impress Pope Benedict XI. The Pope was amazed by the skill needed to recreate such a basic shape, and the concept of drawing a flawless circle has become a symbol of precision across art, mathematics, and engineering.

The Perfect Circle Experiment

As the team worked through the development of the system, they decided the best proof-of-concept experiment was the same simple but precise challenge as Giotto faced; Getting a machine to complete the motion of a perfect circle using augmented operator assistance. This requires articulation of multiple joints in varying load and speed conditions all to be orchestrated simultaneously with precision – a complex and nuanced engineering challenge.

The HUSCO team, drawing from decades of experience in main control valve design and operation, as well as machine understanding from fully instrumented tests on over 100 pieces of equipment, turned this idea into the plug-and-play system now known as Exacto.

Exacto Product

Their hard work created a subsystem that converts digital control signals to hydraulic actuation. The Exacto product includes a functional safety certified controller, model-based control software, and it seamlessly integrates Husco knowledge and technology to provide original equipment manufacturers (OEMs) and machine control operators a standardized hydraulic application programming interface (API) to digitally control equipment regardless of manufacturer or user.

Welcome to the Future

This story is just one example of how Husco engineers pushed their limits to create a best-in-class solution for the off-highway market. During National Engineers Week 2024, we want to recognize and celebrate how our engineers are making a difference in the world, providing our customers with innovative solutions that enhance productivity, efficiency, and safety. Learn more about Husco’s E-control line here.



Husco’s mission is to be the global leader in products and services that optimize the performance, controllability, and safety of off-highway and automotive equipment. Our engineers, as well as the rest of the Husco team, are a highly-talented, diverse workforce driven by three essential values: intelligent risk-taking, high performance, and practical innovation. Learn more about joining the team here: