Tunneling robot

Tunneling Robots (TR), sometimes also called "moles" after the Terran animal by that name, are specialized robots used to excavate tunnels with a circular or oval cross section through a variety of soil and rock strata. They can bore through anything from hard rock to sand. Tunnel diameters produced by mass produced units range from a metre to over 50m to date. Tunnels of less than a metre or so in diameter are typically done using trenchless construction methods or horizontal directional drilling rather than TRs.

Tunneling robots are used as an alternative to drilling and blasting (D&B) methods in rock and conventional "hand mining" in soil. TRs have the advantages of limiting the disturbance to the surrounding ground and producing a smooth tunnel wall. This significantly reduces the cost of lining the tunnel, and makes them suitable to use in heavily urbanized areas. The major disadvantage is the upfront cost. TRs are expensive to construct, and can be difficult to transport. However, as modern tunnels become longer, the cost of tunnel boring machines versus drill and blast is actually less—this is because tunneling with TRs is much more efficient and results in a shorter project.

Multiple TRs can be programed to work together to create wider voids than what is possible with a single TR for a given height.

The most sophisticated TRs by the mining divisions of SII, Enroe, and WURGUS Engineering amoung others are capable of creating bridges automatically   if need be.