Quote from: Robotbeat on 01/14/2014 10:45 pmRight, but greasing a bearing is just a /tad/ less complicated than the oil system in a car, for instance.The moving parts in oil system of regular car engine:1. oil2. two rotors making up a gerotor pump3. uh .. that was it.
Right, but greasing a bearing is just a /tad/ less complicated than the oil system in a car, for instance.
Quote from: Dalhousie on 01/14/2014 09:33 pmQuote from: Mikesicles on 01/14/2014 04:52 pmAlso I would like to point out that if you were simply moving from one colony to another cable cars would be the most efficient as you could use power centralized at the colony by moving the cable.Is there a maximum length limit for a cableway? The longest on Earth was just under 100 km. I imagine there would be, unlike road or rail, given the need to move the capble.Also have lower gravity, remember.Cableway would make more sense if faced with steep slopes, though, like on Earth. Like from the deep parts of Hellas Basin to the rim. Probably too steep for conventional rail there.
Quote from: Mikesicles on 01/14/2014 04:52 pmAlso I would like to point out that if you were simply moving from one colony to another cable cars would be the most efficient as you could use power centralized at the colony by moving the cable.Is there a maximum length limit for a cableway? The longest on Earth was just under 100 km. I imagine there would be, unlike road or rail, given the need to move the capble.
Also I would like to point out that if you were simply moving from one colony to another cable cars would be the most efficient as you could use power centralized at the colony by moving the cable.
Cableway would make more sense if faced with steep slopes, though, like on Earth. Like from the deep parts of Hellas Basin to the rim. Probably too steep for conventional rail there.
Problem with batteries is they're useless when you need lots of power.
...However if you need lots of energy it still matters. In addition you can quickly refill your tanks, which is of particular importance for machinery that is operating non stop for hours....
Fast, automated battery swap (more automated than fueling) is already commercially deployed on Earth:
Charging is not an issue as it takes only 20–30 minutes to recharge battery.
1) fuel (fuel filter, fuel pump, injectors, fuel tank, fuel lines)2) air (air filters, possibly turbo or supercharger, radiator fan, etc)3) exhaust system (needs to run through the turbo, possibly needs catalytic converter or muffler if on a place like Earth, on the Moon and Mars you might want to capture the water exhaust)4) oil system (all the things you mentioned plus oil reservoir, filter, oil lines, oil channels in engine, oil pressure gauge, etc)5) another system for brakes (including brake oil), which gets used less often in an electric vehicle because of regen braking doing vast majority of the work... you could probably get by with a simpler brake system in an electric vehicle, and electric brakes certainly exist.6) cooling system (if not air-cooled) (sometimes needed for high-performance electric vehicles, but generally optional for electric vehicles), pump and radiator and reservoir, etc.7) In a gasoline vehicle, you need a spark generation/distribution system. Plus, you still need a complicated mechanical system for converting the mechanical energy of the pumping cylinders to rotation, then a transmission and clutch to convert to the right rpm to be suitable for the wheels (and you need transmission oil).9) Plus you still need a starting motor and alternator and a decent battery, basically duplicating in miniature all the systems needed for an electric car.
I say with honesty that it is remarkable that we've gotten the price of ICEs down as low as they are, considering how complicated they are. There are just SO many systems that you need for them to work reliably and with decent performance and/or efficiency. Getting all those systems to work on another planet is going to be an enormous challenge. An ICE vehicle needs 5 or 6 different fluid systems to work reliably. An electric vehicle needs basically none (just electricity), enormously simplifying the entire thing.
Charging an electric vehicle is vastly simpler than mining water, purifying it, electrolyzing it, liquifying the gases, storing the fuel cryogenically, and then transferring it to a vehicle (in a vacuum, far below the boiling point of the liquid).
Quote from: Oli on 01/15/2014 09:12 amProblem with batteries is they're useless when you need lots of power.This cannot be further from the reality. Electric drivetrain offers huge torque and this is very useful for super heavy duty vehicles. Electric vehicles can easily output megawatt level power and on
Energy density of lithium sulphur batteries is about 1 MJ per kg
The problem with ICE vehicles on Moon and Mars is not heating, but it is cooling. Due to 100 times thinner atmosphere, the radiator of cooler must be huge and very heavy in order to prevent IC engine from overheating.
Mars conditions cooling of electric drivetrain is easier than the cooling of comparably powerful ICE drivetrain.
Fast, automated battery swap (more automated than fueling) is already commercially deployed on Earth:*Tesla stage(d) show utub link removed*
As if filling Audi A8 running on fumes (gas tank is 23.8 gallons) is equal to Model S battery switch. Pump delivered 23.22 gallons after which the sloth spent a minute meditating or something before getting the car moving again. A8 does 21 mpg combined so the fuel load gives 488 miles, 650 miles if highway. Had the sloth pumped the mileage equivalent of model S larger battery pack (265 miles) he would have pumped 75 seconds + meditating. OT I know but the stench of marketing horse excrement overwhelmed me.
Also I wonder what the effect on the lifetime of the battery is if you do it often.