Mechanical engineers at Rice University have developed a handy extra limb for better grasping of objects. These arms are powered by compressed air.
The prototype ’arm’ is a piece of fabric that hugs the body and extends outward upon activation. The elastomer lining on it enables gripping the slippery objects. The team has also built a shirt with a bellows-like actuator that is attached to the armpit. This attachment enables the wearer to pick up a 10-pound heavy object. The researchers demonstrated this on a mannequin which showed that these extensions do not require human muscles for activation.
The researchers from Preston labs also tested these materials with the football players. The system requires textile pumps that are embedded in the soles of shoes. These pumps harvest air pressure while walking and the pneumatic actuators use this pressure when required. These pumps are filled with open-cell polyurethane foam. This foam enables them to recover their shape after every football game.
The results of the tests by Rice lab showed that these devices can produce an equivalent of watts power. The conversion efficiency was more than 20%, outperforming other strategies used for foot-strike energy harvesting.
The components for making a single device costs USD 20. These products are simple to assemble and can be washed in washing machines without degrading its future performance. The lab also developed mathematical models for predicting the performance based on weight, walking speed and other parameters. These devices are expected to make a huge difference in the robotics industry in the future.
“Census statistics say there are about 25 million adults in the United States who find it difficult to lift 10 pounds with their arms,” said Rajappan, a postdoc supported by the Rice Academy of Fellows. “That’s something we commonly do in our daily lives, picking up household objects or even a baby.”