A photo of the arm fully extended (on Mars in 2012). The 7-ft-long (2.1m) arm maneuvers a turret of tools including a camera, a drill, a spectrometer, a scoop, and mechanisms for sieving and portioning samples of powdered rock and soil. (Source: NASA/JPL-Caltech)
Excellent post Dave. It's amazing to me how dedicated engineers always find a way to make it work. Also its obvious NASA appointed the right individual to lead this team. I wonder if Congress would be so accommodating today if delays of this type presented themselves for comparable programs.
Mechanical, electrical and power management issues are common to many designs, but not many engineers have such a hard deadline as a launch window to contend with. The men and women who work on these extra-terrestrial projects have a lot to contend with and my hat's off to them and the managment team that make these projects happen - despite the long odds for success. Thanks for the post.
Rob Manning asked me to convey that Howard Eisen and his team were mainly responsible for the successful resolution of the issues described in the article. Eisen is the Deputy Flight System Manager, and like Manning, has been closely involved in all of NASA's Mars rover missions, from Sojourner in the late '90s to the Curiosity rover today.
Of course, the success of the Curiosity rover is the product of the work of literally thousands of people, at NASA and at their suppliers (including Aeroflex and Yardney, among others) and other partners.
Dave; thanks for that. Yardley website indicates the Lith-Ion cells are good to 2100 deep cycles. That's unheard-of in the consumer electronics industry. I had been making vague assumption's that, while the Consumer Market and the Aerospace industries have vastly different needs, that the basic physics and chemistry of the batteries would be a common denominator. Certainly NOT the case at 2100 cycles. That's approximately 3-4 times better than the high-end expectations for Consumer portables at about 600 cycles. I'm book-marking that Yardley site, for sure. Thanks!
@JimT: I don't have a definite answer on the battery life, but this status report says that "the batteries are expected to go through multiple charge-discharge cycles per Martian day." The rover is supposed to last at least one Martian year, or about 669 Martian days. So it sounds like the batteries are expected to last well over a thousand charge-discharge cycles.
Great article, Dave. The obvious emotion among the engineers in image #6 is a reminder of the comments from NASA engineers in the late '60s and 70s, who used to go outside and look at the moon for inspiration during late night work sessions. As you point out, this is a dream job for most engineers.
Good article, Dave. One detail that caught my attention was the description of the thermoelectric generator used to charge (and repeatedly re-charge) lithium batteries. I didn't realize the Curiosity was stocked with multiple Li-Ion cells, and knowing that this type of chemistry has a relatively finite life span of charge/discharge cycles (about 500-600 times) that definitely seems to dictate a finite life span. Of course, that span could be measured in decades if one cycle were several weeks long. Is that the case-?
A really interesting article on what happens behind the scenes to design a better machine by learning from what didn't work in the past, and also having the patience to see it through. That it's about one of the most interesting and well-known robots to be created in the last decade also makes it a worthwhile read. Thanks for the blog post, Dave.
That's what it takes. The problems in space systems are generally very difficult becuase the conditions do not occur, in general, on earth. In addition, except in a limited number of cases, once a system is launched, that's it.
Generally, the budgets are a lot bigger than for terrestial based systems. They are not unlimited, but sometimes they seem to be. The comment about missing the date is instructive. In a normal engineering situation, you might actually abandon a product development if you miss a key date. This could be a model year or a selling season (e.g., XMAS). When RIM announced that their Blackberry 10 phones would not come out until late January 2013, their stock fell. This is equivalent to the constant threat of Congress cancelling or delaying a program. It can be really frustrating for the engineers involved.
Many diverse markets take advantage of semiconductor IP; so many that no one can recite the entire list without leaving off several. So why do we track all the vertical markets? They all have a unique set of requirements and value attributes differently. One major vertical market segment is automotive.
In November, a European space probe will try to land on the surface of a comet moving at about 84,000 mph and rotating with a period of 12.7 hours. Many factors make positioning the probe for the landing an engineering challenge.
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