One of the challenges of field testing planetary rovers on Earth is the difference in gravity between the test and the intended operating conditions. This not only changes the weight exerted by the robot on the surface but also affects the behaviour of the granular surface itself, and unfortunatly no field test can fully address this shortcoming. This research introduces novel experimentation t...

Burrowers and borers are ecosystem engineers that alter their physical environments through bioturbation, bioirrigation and bioerosion. The mechanisms of moving through solid substrata by burrowing or boring depend on the mechanical properties of the medium and the size and morphology of the organism. For burrowing animals, mud differs mechanically from sand; in mud, sediment grains are suspend...

OBJECTIVE To compare the morphology of normal, healthy Gottingen minipig retinal vessels of the optic disk with experimentally induced glaucomatous optic disks in order to identify the glaucomatous excavation. Present results were compared to human glaucoma findings. PROCEDURE Sixteen eyes from eight Göttingen minipigs were studied using fundoscopic photography and fluorescein angiography. Ex...

US gas companies spend over $300 million annually detecting and repairing gas leaks in urban and suburban settings. The current approach is one of above ground leak detection and pinpointing, followed by excavation, repair and restoration. The major cost incurred is typically that of digging and restoring the excavation site. The Gas Research Institute (GRI) and the National Aeronautics and Spa...

According to construction scheme of some weak surrounding rock large span double and multi-arch tunnel works, finite element value simulation method is adopted to research weak surrounding rock deformation characteristic, anchor bolt mechanics characteristic, preliminary support and secondary lining structure mechanical characteristics, etc, and the research result shows that: repeatedly distur...

A novel experimentation and analysis technique has been developed to enable detailed investigation of robot interactions with granular regolith. This technique, the Shear Interface Imaging Analysis Tool, provides visualization and analysis capability of soil shearing and flow as it is influenced by a wheel or excavation tool. The method places an implement (wheel, excavation bucket, etc.) in gr...

Nowadays, excavators play an important role in construction machinery. Among them, pneumatic excavators are suitable selections for some specific applications, because of their advantages. As a new trend, automation of excavation helps improving productivity, safety, and reducing of operation costs, consequently, making construction works become feasible even in hostile environment. In traditio...

Characterization of Excavation Damaged Zone (EDZ) around an underground excavation is a major research topic for deep geological disposal of medium to high level radioactive waste. Rock fracturing due to excavation and thermal loading and its resultant rock mass permeability change in the EDZ are important aspects in the EDZ characterisation. A new function to predict rock mass permeability cha...

Current spacecraft need to launch with all of their required fuel for travel. This limits the system performance, payload capacity, and mission flexibility. One compelling alternative is to perform In-Situ Resource Utilization (ISRU) by extracting fuel from small bodies in local space such as asteroids or small satellites. Compared to the Moon or Mars, the microgravity on an asteroid demands a ...

-Soil is the most abundantly available construction material on the earth. At places it is found to be the only locally available construction material. Backfilling of utility trenches is done with the soli available from the excavation of the trenches. Properties of this backfill soil vary from site to site depending upon the material available from excavation. Many times due to use of poor so...