Moon Shot, Japan-Toyota...

[TrevorMonty]

Fuel Cell means tanks of liquid hydrogen, stored in the vehicle long term. Is it not a problem nowadays? And the reason you can't have space hydrogen tanks waiting for a vehicle in orbit?

It may not be liquid hydrogen. This design has 15 tanks. For argument's sake, I will make a few assumptions

1.)tank diameter = .3 meters
2.)tank length = 2 meters
3.)tank pressure = 1000 bar (a bit higher than the consumer grade 700 bar tanks in current hydrogen cars)
4.)the tanks shown are the hydrogen tanks and the O2 tanks aren't shown
5.)gas temperature = 10 degrees C

Each tank therefore is .14 cubic meters of volume and all tanks have a combined volume of 2.1 cubic meters. This translates to ~92,500 moles of hydrogen with a molar mass of 2 grams / mole or a total hydrogen storage capacity of 185 kg. For reference, the Hyundia Nexo is a SUV with a range of 380 miles and a hydrogen storage capacity of 6.3 kg or a fuel economy of 60 miles per kg. If this could get similar fuel economy (because of lower gravity and no air resistance despite the larger size and poor road conditions), the range would be 11,100 miles. 

edit: Adjusting my assumptions, if there are 10 tanks of H2 and 5 tanks of O2, this would reduce the range by a third to ~7400 miles or ~12,000 km. Hydrogen storage capacity would be ~123 kg and O2 capacity would be ~1000 kg.

For life support during lunar night allow for 1kg per 2kwh. I'm not sure if that 2kwh is all 100% electricity or mostly electricity with some waste heat . Either way they should be able to use all of it as heating will be biggest power consumer for life support. Don't how much power is required during lunar night for live support, but needs to survive 336 hours of darkness. Maybe case of sitting out the night to conserve power. Shouldn't have any problems keeping rover from freezing when unmanned, even mobile.

What's not clear is if it will convert water back into H and O for storage during day or be refuelled between missions.

[TrevorMonty]

The market for rover of this size for servicinb lunar base could be dozen or more.
1)Exploration rover to support 2 crew for weeks.
2)Day excursion rover carrying 6-8 around lunar base and servicing landers. Could get away with just battery and solar power.
3)Unmanned mining rovers, with or with fuel cells depending where they are working.
4)Unmanned trucks for supply runs between lunar base and outposts.

 

[ncb1397]

If lunar night is a problem, a rover platform can navigate around it. You have to maintain ~9 miles per hour at the equator and that goes down as you approach the poles.

Probably the best thing to do during lunar night is to keep moving to wherever you are headed. Fuel cells generate quite a bit of waste heat.

edit: Doing some pixel measuring on the solar array - it looks to be ~2.5 meters by ~3.8 meters. This should generate about 3 kw continuously with sun tracking. If we go by the assumption that you might be able to get similar mileage to SUVs, electric vehicles get about 3 miles per kwh. This should be able to produce power for about 9 miles each hour of charge. It may not be able to drive and charge though, so it couldn't out run lunar night continuously at the equator. Polar regions should be fine though.

[su27k]

This is vaporware. It is going nowhere. If they had proposed something small, I would have believed it.

Interesting, $270 billion revenue company proposes rover, it is vaporware. $2 billion revenue company proposes BFS (many times the size), nobody bats an eye lid.

He probably thinks BFR is vaporware too....

Also, it helps that the $2 billion revenue company is already flying something 1/3rd the size of BFR...

But as a fan of SpaceX, I'm glad to see JAXA and Toyota is thinking about rovers like this, we'll need payloads like these once BFR can send 25 to 100 tons to lunar surface. The rover size is not large at all, I think it's just about right for a pressurized long range rover with airlock.

[Lar]

This rover is at the stage of "bending light" (powerpoint), and is a nice distraction/PR effort for a company whose main focus is elsewhere.

SS/SH is at the bending metal stage, and is a parlay of what has been invested and won back so far, as was just about everything else Musk has done, starting from a gift computer.

Totally different credibility levels.

[MickQ]

If lunar night is a problem, a rover platform can navigate around it. You have to maintain ~9 miles per hour at the equator and that goes down as you approach the poles.

Probably the best thing to do during lunar night is to keep moving to wherever you are headed. Fuel cells generate quite a bit of waste heat.

edit: Doing some pixel measuring on the solar array - it looks to be ~2.5 meters by ~3.8 meters. This should generate about 3 kw continuously with sun tracking. If we go by the assumption that you might be able to get similar mileage to SUVs, electric vehicles get about 3 miles per kwh. This should be able to produce power for about 9 miles each hour of charge. It may not be able to drive and charge though, so it couldn't out run lunar night continuously at the equator. Polar regions should be fine though.

They could tow a trailer with a similar sized panel on a gimbal mount.

[Tywin]

Bridgestone, joint to the mission with JAXA and Toyota...

Bridgestone Corporation has announced that it will take part in an international space exploration mission together with the Japan Aerospace Exploration Agency (JAXA) and Toyota Motor Corporation. Recently announced by JAXA and Toyota, the goals of this mission are to expand the domain of human activity and develop intellectual property on space exploration. Bridgestone's mission assignment is to research the performance needs of tires for use on manned, pressurized rovers*1 in order to help these rovers make better contact with the surface of the moon.

http://www.moondaily.com/reports/Bridgestone_Joins_International_Space_Exploration_Mission_with_JAXA_and_Toyota_999.html

[ncb1397]

They recently announced an agreement in July. Toyota's Press release has details on the planned timeline:

Fiscal year 2019   Identifying technological elements that need to be developed for driving on the surface of the moon; drawing up specifications for a prototype rover*
Fiscal year 2020   Manufacturing test parts for each technological element; manufacturing a prototype rover
Fiscal year 2021   Testing and evaluating both the manufactured test parts and the prototype rover

...

Tentative plan aiming to launch the lunar rover in 2029

From 2022   Manufacture and evaluation of a 1:1 scale prototype rover; acquisition and verification testing of data on driving systems required to explore the moon's polar regions
From 2024   Design, manufacture, and evaluation of an engineering model of the rover; design of the actual flight model
From 2027   Manufacture, and performance and quality testing of the flight model

https://global.toyota/en/newsroom/corporate/28866297.html

[gaballard]

It looks like the rover equivalent of the crazy prototype car designs that get shown off at car shows but never get anywhere near production.

[ChrisWilson68]

It looks like the rover equivalent of the crazy prototype car designs that get shown off at car shows but never get anywhere near production.

Yeah, but with some government handouts thrown in for good measure.

It's yet another project where there's a near-term component that is cheap enough for the government to actually fund that builds some hardware that won't actually be used, and a long-term component that is fantasy and won't ever happen.  The only real value would be in the fantasy component.

But the government and the company get their PR and the people working on it get their jobs.  Only the taxpayers lose.

[Zed_Noir]

Will point out that the Toyota Lunar Rover as described by the images so far can only be transported to the Lunar surface in a Chomper Starship. It is too big to go through the Starship cargo hatch.

[JulesVerneATV]

Japan Says It’s Ready To Help With U.S. Lunar Missions As Trump’s Budget Pullback Hits NASA

https://offthefrontpage.com/japan-says-its-ready-to-help-with-u-s-lunar-missions/

[DanClemmensen]

Will point out that the Toyota Lunar Rover as described by the images so far can only be transported to the Lunar surface in a Chomper Starship. It is too big to go through the Starship cargo hatch.

Not quite correct. True, it cannot be transported in an HLS, but we do not know what the configuration of the Ship will be, and "chomper" is unlikely.

[BN]

Japan Says It’s Ready To Help With U.S. Lunar Missions As Trump’s Budget Pullback Hits NASA

https://offthefrontpage.com/japan-says-its-ready-to-help-with-u-s-lunar-missions/

jaxa's annual budget is barely 1 billion usd