Design of a bimodal self-burying robot
Subterranean exploration so far has primarily been performed with the assistance and involvement of human beings. As more ground is broken and more layers are explored, the need for a robotic solution to make digging both easier and safer becomes greater. The applications of a self-burying robot extend from mining and military applications to humanitarian applications. This paper elucidates design principles that form the foundation for self burying robots. In this paper, a bimodal robot is described which is capable of travelling above-ground in one mode and capable of burying itself in the other mode. The variables that affect digging are examined, as well as the design decisions made in order to optimize the resources available to the robot. Finally, future work in the area of self-burying robots is discussed.
Subsurface Explorer Robot with Peristaltic Crawling Mechanism
In recent years, unmanned planetary explorations have received a lot of attention in the world. Direct exploration missions to land softly and traverse on the surface of the moon or other planets have been studied and planned in the world. Japan has earnestly studied lunar lander-rover missions. In these missions, it is required to conduct in-situ analysis of geological samples and deploy devices for measurement and observation. Recently deep drillers or penetrating systems have been required to obtain deep data for subsurface exploration. In lunar or planetary missions, it is needed to excavate the regolith layer, which covers the lunar surface, in depth of several meters. This paper, describes lunar or planetary mission scenarios and scientific requirements. A detailed surface and subsurface exploration by a mobile explorer is presented. Then this paper proposes a worm-typed drilling robot which is maneuverable in regolith by peristaltic crawling and the developed earth auger. A new mechanism to move forward in the soil is described. A propulsion unit using dual pantographs with a large area of an expansion plate is developed. The drilling function is studied by analyses and some experiments. The experimental results show the feasibility of the proposed robot.
The Dynamics of Burrowing of Some Common Littoral Bivalves
1. The burrowing activity of Donax vittatus, Tellina tenuis, Macoma balthica and Cardium edule consists of a cyclical series of changes, termed the digging cycle, involving protraction of the foot, closure of the siphons, adduction of the valves and retraction of the foot. 2. Detailed comparison shows marked difference in the time involved in pedal protraction and a see-saw motion of entry to the sand by Cardium and Macoma with bulging shells in contrast to a more direct downward movement of Donax and Tellina with slim shells. 3. The structure of the foot and the hydrostatic fluid-muscle mechanism is described. 4. Recordings were made of the hydrostatic pressures directly by cannulation of the mantle cavity or pericardium and indirectly from the sand adjacent to the foot. 5. While extension and probing occurs at relatively low pressures dilation of the foot and ejection of water from the mantle cavity occur simultaneously at pressures of 25 cm. of water and are caused by the adduction of the valves. 6. The foot obtains a firm anchorage by means of the dilation while the pedal retractors pull the shell downwards and so sustain the pressure in the haemocoele. 7. Water ejection from the mantle cavity loosens the adjacent sand so that penetration by the shell is facilitated.