Check this article from the NASA Science News (link).
Five years and they are still operating. They must have used Barry’s drives with Tony’s controls, all put together by TOC!!
Happy RRing,
Jerry
Kindof amazing, eh?
I wonder if they’re going to stumble over the little pathfinder wandering around.
Methinks the next generation of rovers will be designed knowing that if so designed, they can operate almost indefinetly on the Martian surface. These little buggers were only supposed to operate for 3 months, but they’ve become NASAs Energizer Bunny’s.
(http://science.nasa.gov/headlines/y2009/images/marsroverupdate/sunset.jpg)
Martian sunset
You have no idea.
The guy who designed the control circuitry and drivers for the Mars Rover is, well, known to Tony.
One of the reasons our controllers are so bullet-proof.
See! I knew there had to be some connection to get that kind of range, battery life and performance.
Actually, I have a vague memory of that connection being mentioned in the past.
Happy RRing,
Jerry
So what kind of batteries do they use?
They have to be solar re charged.
John Bouck said:That's what I want to know. It seems I'm lucky to get a year out of any rechargable batteries I use. I'm ready to junk all my cordless tools. Tired of replacing batteies and chargers. Ralph
So what kind of batteries do they use? They have to be solar re charged.
The Mars Rovers, Spirit and Opportunity, have several batteries, but the main power system batteries are lithium-ion technology. Silicon solar panels are the primary power source. When launched in 2003, these two Mars missions were the first use of Li-Ion technology in space applications. This combination has obviously worked well, but there is a lot more to consider.
First, this battery type was chosen for factors such as the high available power density and the ability to work at freezing temperatures. The rovers needed lots of power during the landing and un-stowing phase, where the solar panels were not yet in use, so the relatively high amount of stored energy was a big plus. The Li-Ion’s higher (than other technologies) cell voltage allows for better power use, with less need for voltage dropping appliances.
The rovers can draw up to 150W when on battery power, but for most of the time they are in operation, including in motion, they use solar power directly, with the batteries being charged using the excess. The rover batteries do provide power during the night, but those needs are relatively small. Note the linked article’s comment, “Sticky dust on Spirit’s solar panels has reduced power to the rover.” That is limiting how far and fast Spirit can travel, regardless of the batteries.
Another consideration is that the rover batteries will never be subject to accidental over charging, nor will they ever catch fire in someone’s car trunk. Before anyone challenges that, be assured that I do believe that using the correct charger system on Li-Ion technology batteries will totally prevent these occurrences.
The bottom line on batteries is appropriate technology. I still use Ni-Cd batteries for my engines, as they are highly available, cheap, and reliable. As Li-Ions become more available and cheaper (as is currently happening), I will probably use some.
Happy RRing,
Jerry
Li-ons!
Then TOC would have nothing to do with it!
It’s niCads or nothing over there. 
Curmudgeon said:
You have no idea. The guy who designed the control circuitry and drivers for the Mars Rover is, well, known to Tony.One of the reasons our controllers are so bullet-proof.
The initial ELITE-3 design, component specifications and operating program was made by Mike Zemek, who at the time was a senior design engineer with Texas Instruments in Houston. Before they got taken over by Micron.
Mike then went to NASA to design the eyes for robots to remotely fix satellites in space controlled by operators on the gound.
M. Verbrugge said:
Not sure things are going as well as you may think...
That October 2008 article in The Onion is a hoot!
John Bouck said:In spite of my lame attempts at humor above, I truly didn't know TOC & company actually built space exploration devices, much less that they recommended a specific battery technology for said space explorers.
Li-ons! Then TOC would have nothing to do with it! It's niCads or nothing over there. :) :) :)
I do know that RCS generally recommends Ni-Cad battery technology for more earthly systems. I also know that I have been operating said RCS earthbound systems using the recommended Ni-Cad technology for well over 15 years with total satisfaction.
As I wrote above, the key is to use appropriate technology in each application. As an example, no one would recommend a group 58 12V lead acid car battery for a flashlight regardless of the fact that I can list several advantages to using that technology in the flashlight application. In battery power applications, one size (or technology) does not fit all.
The radio controlled firefighting machine my company designed & prototyped last year uses absorbed glass mat (AGM) batteries. The customer’s stated design goal was to be able to position the machine out to ~700 feet, do some minor repositioning, then be able to operate the fire suppression appliances at 50% duty cycle for ~8 hours. The machine we designed and built using AGM batteries is actually able to position out to 1200 feet, reposition another 1200 feet, and operate at 50% duty cycle for ~48 hours. At that time, it is still operational and has ~20% of its battery capacity remaining. Three things have combined to arrive at the high performance values: 1) Careful analysis and design of the total power system, including batteries, charger, motors, R/C gear, etc.; 2) Exceptional charging, power storage, and power output capability of the chosen AGM batteries; 3) The successful application of an on-board micro-PLC for management of all vehicle systems and functions. In spite of this success, I do not envision using AGM batteries in my locomotives at anytime in the future.
Happy RRing,
Jerry
Hi Jerry.
I am one of those people who listen to good advice and try and put it into practice.
Most of the stuff ups RCS has experienced over the years have been down to me playing around with what Mike Zemek designed in the first place. The LMD18200T solid state motor driver IC Mike stipulated was apparently submitted by NSD for use with the space program. Mike Z realised it could be used for our purposes and it has proven to be extremely reliable. I know using that 11 pin IC makes my stuff expensive, but they sure are bullet proof.
It has only one drawback in that, if the input battery voltage drops below a 12 volt threshold, it can behave erratically.
This is where battery chemistry and cell size comes in.
If an operator tries to draw too much current from el cheapo AA size NiCd and NiMh batteries the voltage will sag. Quite dramatically at times.
Sub C size cells can handle high current draws and these are the ones experience has taught me are the way to go. At least for now.
Elsema make the TX’s and RX’s. They have been doing the same basic RF output design since 1974 when it was first approved. These are generally pretty reliable but do not like being dropped. The crystals an be damaged.
Mike married the Elsema equipment to his controller design.
I keep an open mind about other battery chemistry and ultimately expect LI-Ion & Li-Poly to provide value for money for our purposes.
I love the onion! Amazing how true made-up news can be 
<< I also know that I have been operating said RCS earthbound systems using the recommended Ni-Cad technology for well over 15 years with total satisfaction.>>
That’s all I use as well.
I do listen and absorb information from Tony and TOC.
They may (NiCad) be a little heavier than others, but they run and run and run…
without all the safety rules you need to follow when re-charging.
Sorry for the hi-jack.
Should be in the Battery forum.
TonyWalsham said:
Hi Jerry.I am one of those people who listen to good advice and try and put it into practice.
Bolshevic!
You’ve never listened to me, have you? :lol: