Development of a breadboard for a planetary coil tubing drill that will be used for sampling planetary soil down to 20m. The prototype, developed with COTS components, is compatible with principle space constraints and features functions and subsystems to allow a demonstration in a suitable environment

 

EXOMARS features a multi-stem drill, pioneered by the MIRO driller (TRP result in 2001), capable of acquiring samples 2 meters down in the ground.Multi stem drills are the right solution for shallow depths, however for reaching deeper they present problems that are too difficult to solve within the constraint of space missions. Drillers of this type require a cumulated length of pipe as long as the depth reached, which translates into a large mass. Furthermore friction increases with depth so for any drill larger than few meters, the well must be lined. Lining pipes introduce additional mass penalty.

 

An alternative class of Subsurface Explorers or Moles can be considered to serve as deep drillers. These systems eliminate the rigid connection between the surface and the drilling head by allowing the latter to move independently.

ESA, has promoted the use of moles in small missions (BEAGLE mole in 2000) Moles can reach deep but they cannot reliably return samples to the surface, hence this activity will develop a drill system with the sample acquisition capability of multi-stem drill and small resources implied by a mole.

 

In terrestrial mining this system is called a coil tubing drill and can be adapted for space use. The activity shall develop a breadboard of planetary coil tubing drill capable of demonstrating acquisition of 2 cm?3 of pristine sample at a depth of 20 metres.

 

This activity shall

- define requirements for the breadboard

- define a preliminary design of the system and its subsystems

- prototype critical subsystems to validate the functioning

- detail design the prototype

- manufacture assemble and integrate the prototype

- test and demonstrate the prototype in a suitable environment