January 30, 2013
Curiosity Conducts “Pre-Load” Tests As It Prepares To Drill Into Martian Rock For First Time
Lawrence LeBlond for redOrbit.com - Your Universe Online
NASA´s Curiosity rover is preparing to use its drill to bore into a Martian rock in the coming days. The rover carried out “pre-load” testing on January 27, placing the drill tip on a series of four locations on the rock and pressing down to test whether the amount of force applied to the hardware matches predictions formulated by NASA engineers.
The team next planned to have Curiosity conduct an overnight pre-load test, into Monday morning January 28, to gain assurance that the large temperature change from day to night at the location doesn´t add excessive stress on the arm while pressing on the drill. The temperature is a real issue as daytime highs of 32 degrees F can plummet to -85F overnight. During this temperature shift, the rover´s arm, chassis and mobility system can grow and shrink by close to a tenth-of-an-inch.
Daniel Limonadi, JPL lead systems engineer for Curiosity´s surface sampling and science system, said that the team does not plan to leave the drill in a rock overnight once drilling commences, “but in case that happens, it is important to know what to expect in terms of stress on the hardware.”
Limonadi said the “pre-load” testing used lower values than will be used during actual drilling so the team can learn about temperature effects without putting too much unneeded strain on the hardware.
He said remaining prep tests will take pretty much all week, some of which will consist of hardware checks and evaluations of the material at the drill site.
"We are proceeding with caution in the approach to Curiosity's first drilling. This is challenging. It will be the first time any robot has drilled into a rock to collect a sample on Mars,” Limonadi remarked.
The tests will also include a “drill-on-rock checkout” that will use the hammering action of Curiosity´s drill briefly, without rotating the drill bit, to assure that the back-and-forth percussion mechanism and control system are properly tuned for drilling into the veined rock, which has been named “John Klein,” in honor of former Mars Science Laboratory deputy project manager John W. Klein, who died in 2011.
They will also perform a “mini-drill” designed to produce a small ring of tailings (drilling residue) on the surface of the rock while penetrating less than eight-tenths of an inch into it. "The purpose [of this procedure] is to see whether the tailings are behaving the way we expect. Do they look like dry powder? That's what we want to confirm," added Limonadi.
The upcoming drill experiment, along with other experiments inside the Gale Crater, is being completed by NASA´s Mars Science Laboratory Project to look for signs that Mars may have once offered the conditions for a habitable environment for microbes and other organisms.