Quote from: jarnu on 03/13/2019 08:47 amFuel 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 assumptions1.)tank diameter = .3 meters2.)tank length = 2 meters3.)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 shown5.)gas temperature = 10 degrees CEach 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.
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?
Quote from: Blackstar on 03/13/2019 12:28 pmThis 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.
This is vaporware. It is going nowhere. If they had proposed something small, I would have believed it.
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.
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.
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 roverFiscal year 2021 Testing and evaluating both the manufactured test parts and the prototype rover...Tentative plan aiming to launch the lunar rover in 2029From 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 regionsFrom 2024 Design, manufacture, and evaluation of an engineering model of the rover; design of the actual flight modelFrom 2027 Manufacture, and performance and quality testing of the flight model
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.
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.
Japan Says It’s Ready To Help With U.S. Lunar Missions As Trump’s Budget Pullback Hits NASAhttps://offthefrontpage.com/japan-says-its-ready-to-help-with-u-s-lunar-missions/
It’s not exactly like the moon — there’s too much gravity and way too much atmosphere. Still, the ranch serves its purpose as a gritty, real-world showcase for how these vehicles may soon ferry astronauts around the surface of the moon.
According to NASA, the rover which is nicknamed ‘Lunar Cruiser ‘ will significantly employ Solar Energy through electrolysis by splitting water into Hydrogen and Oxygen during extended Lunar days,which will be stored in Fuel Cells to power the vehicle during the night.
