Coming robots move gracefully like humans

A team of engineers at Disney Research has developed a system that will help robotic arms move swiftly and gracefully with precise control.

Called hybrid fluid transmission, the system will enable soft interactions between people and the machines in homes and at work places.

"We have combined the best elements of a hydraulic system with the best elements of an electric motor system," said Peter Whitney, associate research scientist at Disney Research Pittsburgh.

The transmission allows robot limbs to be light, strong and graceful while driving them with easily controlled, low-friction motors.

The motors, which normally would add significant weight to the limbs, can be mounted on the robot body instead.

"The result is a system that can efficiently transmit power with little friction. Yet it is also 'backdriveable,' capable of absorbing energy as well as transmitting it," Whitney added.

In contrast to conventional hydraulic systems which are prone to leakage, the new passive fluid transmission uses pairs of rolling diaphragm cylinders connected by fluid-filled lines.

The system transmits force so efficiently that the team found they could build an entirely passive "puppet" system, moving one robot arm by manipulating a second robot arm linked to it with the transmission.

"One possible application of a system would be as a surgical robot compatible with use in a magnetic resonance imaging (MRI) device," Whitney suggested.

The team recently presented a research paper on the project at "IROS 2014", the international conference on intelligent robots and systems in Chicago.