The Sample Handling System for the Mars Icebreaker Life Mission: From Dirt to Data

Abstract

The Mars Icebreaker Life mission will search for subsurface life on Mars. It consists of three payload elements: a drill to retrieve soil samples from approximately 1 m below the surface, a robotic sample handling system to deliver the sample from the drill to the instruments, and the instruments themselves. This paper will discuss the robotic sample handling system. Collecting samples from ice-rich soils on Mars in search of life presents two challenges: protection of that icy soil--considered a "special region" with respect to planetary protection--from contamination from Earth, and delivery of the icy, sticky soil to spacecraft instruments. We present a sampling device that meets these challenges. We built a prototype system and tested it at martian pressure, drilling into ice-cemented soil, collecting cuttings, and transferring them to the inlet port of the SOLID2 life-detection instrument. The tests successfully demonstrated that the Icebreaker drill, sample handling system, and life-detection instrument can collectively operate in these conditions and produce science data that can be delivered via telemetry--from dirt to data. Our results also demonstrate the feasibility of using an air gap to prevent forward contamination. We define a set of six analog soils for testing over a range of soil cohesion, from loose sand to basalt soil, with angles of repose of 27° and 39°, respectively. Particle size is a key determinant of jamming of mechanical parts by soil particles. Jamming occurs when the clearance between moving parts is equal in size to the most common particle size or equal to three of these particles together. Three particles acting together tend to form bridges and lead to clogging. Our experiments show that rotary-hammer action of the Icebreaker drill influences the particle size, typically reducing particle size by ≈ 100 μm.

Robotics and Automation for “Icebreaker”

“…Icebreaker's performance in permafrost in field conditions meets the design constraints and requirements for the subsequent Icebreaker and/or Red Dragon flight drills. Through Mars chamber and field tests in relevant analog environments, NASA and Honeybee have increased the technical maturity of planetary drilling, improved the potential astrobiology science quality (through mitigation of sample contamination), and reduced planetary‐protection mission risks in Category IVc areas to acceptable levels (Dave et al., ).…”

“…A relatively simple four degree of freedom (DOF) manipulator arm moves the samples from the catchment up to the spacecraft deck with input hoppers, and places the samples in them. A separate recent paper (Dave et al., ) discusses the sample transfer arm and its end‐effector designs in more detail.…”

“…JPL's Mojave Mars Simulant (MMS) (Beegle et al., ) was mixed with 1% perchlorate (ClO 4 ) by mass, then the top 20 cm of each test section was mixed with 30% water by mass, creating alternating ice layers with ice‐cemented simulant, and then a cap of 7 cm dry MMS was emplaced. As described in Dave et al (), this was intended to approximate the Mars polar conditions encountered by Phoenix.…”

Intelligent Drilling and Coring Technologies for Unmanned Interplanetary Exploration

“…So far, the former Soviet Union's Luna series is the only unmanned detectors that successfully implemented the lunar subsurface soil's sampling and returning [17,18]. Among them, the Luna 16 detector launched in 1970 with a stretched out arm mounted rig sampling method successfully drilled into 350 mm beneath the lunar surface, acquiring 101 g soil sample finally [19]. The following Luna 20 detector launched in 1972 landed on a lunar plateau with a similar sampling device to the Luna16 and was forced to stop drilling at 250 mm depth due to multiple times of overheat fault, eventually sampling only 55 g lunar soil [20].…”

Drilling Load Model of an Inchworm Boring Robot for Lunar Subsurface Exploration

“…Drilling is an effective method and is widely utilized in the planetary subsurface exploration missions [2,3]. Though these missions are capable of sampling the regolith or rack by using of the drill with its inbuilt coring tube, these drills are generally designed less than two meters because of the constraints of power, payload, and volume.…”