Engineering news
Four amorphous robot designs: Bladder bot (amoeba design), inchworm robot, electromagnetic sphere robot, and polymer cell robot (from left to right, top to bottom)
Nasa has been awarded a patent for a range of malleable, amorphous robots that could one day be used for search and rescue missions or for space missions on more-extreme environments on the moon or Mars.
Nasa engineer Dr. Arthur Bradley and a team of students at the NASA Langley Research Centre worked on four different amorphous robotic designs that are able to autonomously move across a surface without needing conventional wheels or legs.
Dr Arthur Bradley and his team proposed four designs: the bladder bot, the inch worm, the electromagnetic sphere robot and the polymer cell robot.
The bladder bot moves in a multi-stage process that makes use of a fluid-filled bladder with circulating high-viscosity fluid. Movement of the robot is not based on external moving parts, but due to the propulsion of the contained fluid by an internal valve system. The Bladder Bot can be designed as an amoeba or with rotating fluid compartments.
Mimicking the movement of its invertebrate namesake, the inchworm robot has a tube-like design and locomotion occurs when internal ferro fluid moves through an electromagnetic ring.
The electromagnetic sphere robot design consists of multiple electromagnetic spheres inside a fluid-filled flexible bladder. Motion is initiated when the polarity of the electromagnets are altered sequentially to move the magnetic balls internally, which causes the robotic locomotion.
Finally, the polymer cell robot design consists of multiple polymeric cells encapsulated in a larger flexible outer shell. The cells individually either swell or contract, causing the centre of gravity to change, and the object rolls accordingly.
The scientists said that amorphous robots are particularly useful in dusty and sandy environments in which “greater mobility, passive shape changing, and immunity to dust and contamination are important”. This includes both surface and subsurface robotic exploration.
The research team added: “Amorphous robots are also useful in emergency and industrial activities, such as search and rescue, e.g. exploring rubble following an earthquake, and inspection of oil pipelines or sewage systems.”
The robots would be self-contained, sealed from the environment, scalable and not restricted to a particular robot size. They would also provide a wheel / leg alternative for locomotion and eliminate robot immobility risks associated with locked wheels or legs due to dust or sand accumulation, a problem that the Nasa Mars rover Spirit experienced in 2009.
Bradley is seeking funding to further develop the robotic designs from Nasa or public or private organisations who wish to license the technology for their own purposes.