New Mars

If we did have to restrict ourselves to robots (not my favoured path!) wouldn't it make more sense to have something like the following - an orbiter that sends down mini landers - something like the Titan probe - and takes photos or film as it descends. For say a 3 tonne orbiter you might be able to send down lots of them. You might be able to land them. Has this approach been thought about?

The Cassini-Huygens mission was a flag ship mission which did end up going billions over budget. It is only accomplishable with RTG nuclear batteries and since the U238 production is not going to be restarted can not make any further future missions possible.
That said thou a mission to mars does not need to be nuclear for most areas to which you would land. The concept of going with say 20 MRO in orbit and 60 or more Spirit Opportunity Rover landers would give a huge boost to the response of data gathered in a short period of time.
Of course that would require the Ares V for an all at once style mission or lots of pairings to make it possible with Atlas V or Delta IV....

I agree, I hope we don't get stuck only using robotics, but if we do, their are some awesome robots that could be built.

-Sets of "team" robots on Mars. Basically have Spirit and Opportunity both deployed together. Have 1 go in the front in the front mapping a path for the 1 in the back. The front one would pass 1 target, and go to the next. The one in the back can move between targets much faster because it need only follow the lead robots path. If the front robot get's stuck, the back one can help pull it's sister out. (Ability to do more than twice the science with twice the hardware)

-Martian weather station/ISRU pathfinder. None mobile solar platform launched to the equatorial region of MARS. Upon landing the platform starts spiting water it carried to Mars into Hydrogen and Oxygen. Once it's tanks are full, it fills and releases a weather balloon that carries a small weather platform and camera. Before release the payload would establish contact with both a satellite and the base camp. (1st weather balloon release from Mars, 1st pathfinder for ISRU on mars, Ability to loft a weather balloon into a dust storm)

-Martian sink well. Place an immobile solar or nuclear drilling platform in an area though to have a high content of water. Have the platform drill down as far as it can, then pipe heat to the bottom of the hole. If there is water in the ground the heat will make it flow into the hole. (1st water well on Mars)

-Martian greenhouse. It has been theorized that a plant such as asparagus could grow in Martian soil, if given the right heat and pressure. A small greenhouse that sucks up the soil underneath it and tries to grow asparagus. (First plant grown on Mars)

-Mouse lander. A scaled down version of a human mission to Mars, using mice only. Use prototypes of a manned mars mission for a full up mouse mission to Mars. Include a control group for centrifugal gravity tests, and different levels of radiation shielding. (1st animal on Mars, hopefully 1st animal returned from mars)

Honestly, some of these would be more fun to read about than a flags and footprints mission!

Excellent thought SpacexULA, with the mouse lander as it would be going beyond the current biosat mission scope....I like it

Especially if you could find a long-lived species of mouse. Great idea! I can see the kids movies now!!

That's going to be done, once SpaceX have the capability. It was what Elon wanted to do, but he thought the launch prices were too expensive, and so decided to make his own rockets.

About mice... I've been wondering why they haven't sent MRL mice (Salamander-like regeneration) into orbit, to test their capability for bone regeneration.

I for one think that we shouldn't even consider manned missions before we can do the autonomous stuff reliably, besides we can acomplish much more on the same budget.
I like your idea multiple of robots but I would prefer to see them floating in the atmosphere using balloons. you wouldn't need so many to cover vast areas. It would be cool to have a few at different altitudes though. Imagine the data coming back from those, would be amazing.

U238 production is in the new budget.

Perhaps you mean Pu-238, since U-238 is plain old depleted Uranium?

That is good news, if it's Plutonium. Unless we want a full fledged nuclear reactor (for which you'll hear no complaint from me ), those RTG's are basically the only powersource for outersystem craft.

I believe you are correct. Bolden said in his briefing that the administration asked for "production of nuclear fuels." Of that I am certain, but I'm having trouble finding the line item in the budget.

It's on page 15. And it is Pu-238. MSL proved a problem with our Pu-238 reserves, so that was going to be restarted temporarily anyway, I believe.

The end of the statement is: Restarts Plutonium-238 production w/ DOE to support future missions;

Suggesting to me that they're going to keep our ability to use Pu-238 for future development.