An earthworm-like modular soft robot for locomotion in multi-terrain environments

Robotic locomotion in subterranean environments is still unsolved, and it requires innovative designs and strategies to overcome the challenges of burrowing and moving in unstructured conditions with high pressure and friction at depths of a few centimeters. Inspired by antagonistic muscle contractions and constant volume coelomic chambers observed in earthworms, we designed and developed a modular soft robot based on a peristaltic soft actuator (PSA). The PSA demonstrates two active configurations from a neutral state by switching the input source between positive and negative pressure. PSA generates a longitudinal force for axial penetration and a radial force for anchorage, through bidirectional deformation of the central bellows-like structure, which demonstrates its versatility and ease of control. The performance of PSA depends on the amount and type of fluid confined in an elastomer chamber, generating different forces and displacements. The assembled robot with five PSA modules enabled to perform peristaltic locomotion in different media. The role of friction was also investigated during experimental locomotion tests by attaching passive scales like earthworm setae to the ventral side of the robot. This study proposes a new method for developing a peristaltic earthworm-like soft robot and provides a better understanding of locomotion in different environments

Distributed Driving System For The Excavation Unit Of A Lunar Earthwarm-Type “Leavo” Excavation Robot

The authors have developed a small excavation robot called the “LEAVO” for lunar exploration, and they have confirmed its usefulness as an excavation robot. They then attempted to add a curved excavation function in order for the LEAVO to increase its exploration field. To achieve this goal, it was necessary for the LEAVO’s excavation unit to transmit the motor output torque to the excavation head without any losses. In this paper, therefore, the authors proposed a new driving system called the “distributed driving system,” which reduced the transmission losses by distributing the actuators and arranging them in the frontal part of the robot. Moreover, the authors developed the prototype of this system and measured its output torque as an operational check

Proposal Of Propulsion Unit Based On Earthworm Setae For Underwater Excavation Robot

In this paper, we developed a propulsion unit with bristles imitating the setae of earthworm. This propulsion unit is installed in SEAVO: sub-seafloor excavation robot. To realize underwater excavation by SEAVO, it is necessary to move the soft and fluid sedimentary layer of seafloor surface. As a solution, we focused on the setae of earthworm which live in mud and soft soil. Then, we developed the propulsion unit with bristles imitating the earthworm's setae and measured the performance of the bristlesattached propulsion unit. Comparing the measurement result of the bristles-attached propulsion unit with the previous propulsion unit, we confirmed the usefulness of the bristles-attached propulsion unit

Science on a Deep-Ocean Shipwreck

Author Institution: Departments of Geological Sciences and Zoology, Museum of Biological Diversity, The Ohio state University ; Columbus-America Discovery GroupA five-year scientific investigation of a site on the North Atlantic seafloor, 270 km off Cape Fear, NC, at a depth of 2,200 m, was undertaken in conjunction with recovery operations on a nineteenth-century steamship (SS Central America which sank in an 1857 hurricane while carrying passengers and cargo en route to New York from the California gold fields). Activities in the disciplines of oceanography, marine geology, marine biology, materials science, and undersea archaeology were undertaken with the tele-directed submersible robot, Nemo. The study included field observations at the site (recorded in over 3,000 hours of videotape and 25,000 still photographs), examination of hundreds of deep-ocean specimens and artifacts, and analysis of several experiments deployed on the seafloor. Resting on a gentle slope of the Blake Ridge, the shipwreck environment was cold, lightless, oxygen-rich, and flushed by moderate currents. The sediments were a foraminiferal-pteropod ooze, deposited at a slow rate (1.7 cm/1,000 years). A diverse community of errant and sessile benthic invertebrates and benthopelagic fishes colonized the shipwreck deriving from it food, cover, and a place of attachment. This deep-ocean oasis supported a greater variety and concentration of animal life than did the surrounding ooze habitat. The timbers of the shipwreck were degraded by woodboring bivalves. The iron machinery was extensively corroded and mobilized into flow structures (rusticles) by iron-oxidizing bacteria. Passenger luggage recovered from the shipwreck contained artifacts which provided insight about the life styles of the voyagers during the Gold Rush. This project demonstrated that a holistic approach to a deep-ocean site of historic importance can provide understandings of the interrelated processes which affect cultural deposits on the abyssal seafloor and the marine life that they foster