Scientists create human-robot hybrid that turns people into bionic centaurs

Scientists in China have developed a wearable robot that turns humans into ‘bionic centaurs’ by giving them two extra mechanical legs behind a person.

The system effectively creates a human-robot hybrid that moves in a four-legged configuration, similar to the mythical half-horse half-man creatures.

Developed by a team at Southern University of Science and Technology in Shenzhen, the wearable platform is designed to walk in step with a user while supporting part of the weight normally carried in a backpack.

The team behind the robot, led by Zhixin Tu, Yihao Jiang, and Chenglong Fu, write: ‘The Centaur robot comprises two independent three-DoF robotic legs and a robotic torso, coupled with the human via a passive softening elastic mechanism, forming a human-Centaur quadruped system.

‘This configuration optimises vertical load distribution and provides horizontal forward force acting through the centre of mass of the human during walking. The compliance-based interaction.’

The robotic legs move alongside the wearer, sharing the load and assisting forward motion.

The team add: ‘Experimental evaluation results demonstrate that the Centaur robot effectively adapts to varying human walking directions and speeds while seamlessly collaborating with the human to traverse diverse terrains.’

Unlike traditional exoskeletons, which attach directly to a person’s legs, the new system acts as a separate robotic pair of limbs connected to the user through an elastic interface worn on the back.

Researchers say this allows the robot to take on much of the load-bearing task while the human remains responsible for balance and navigation.

Tests showed the system could significantly reduce the effort required to carry heavy items.

When participants carried a load of about 44lb (20kg), their metabolic energy use fell by roughly 35%, while pressure on the feet dropped by around 52% compared with walking without assistance.

It forms a hybrid walking system in which the robotic legs provide both propulsion and weight support.

Under lighter loads the connection remains relatively firm, helping the user and robot stay coordinated. As the load increases, the system becomes more flexible, allowing the robotic legs to absorb more of the force and carry a greater share of the weight.

This means the human focuses on steering and maintaining balance, while the robot performs much of the mechanical work required to move the load.

The team also developed motion-planning and control systems so that the robotic legs can match the user’s speed and direction of travel.

During trials, the researchers found the robotic legs could support more than half of the weight being carried while allowing participants to maintain a natural walking pattern.

The research team believe such wearable robots could help workers who regularly transport heavy equipment.

Possible applications include military logistics, disaster-relief operations, and industrial transport tasks where supplies must be carried across difficult terrain.

The research was published in the journal The International Journal of Robotics Research.