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Getting to sit on the Rover seat in a stiff pressure suit from the lurain was not so easy. The astronauts found they had to stand facing forward, then with an upward and sideways kick, jump up with their legs and arms stretched out ahead to hopefully land in the middle of their seat.http://www.honeysucklecreek.net/msfn_missions/Apollo_15_mission/hl_Apollo15.html [nofollow]
"They had ample power driving a 1500lb mass with a 1hp vehicle?"So, a bit like a horse then?
Ok,Let's compare the specs of your typical lunar rover to my car.1957 Fiat 500.Curb Weight: 499 kg (1,100 lb).HP: 13 (original 479cc, later upgraded to 499cc, and 17 HP).Top speed of about 55 MPH.Construction, Steel.Lunar RoverCurb Weight, 209 kilos, 462 lbs.Loaded weight, max of about 1600 lbs.Power, 1 HP.Top speed of about 8.7 MPH, or 14 KPH.Construction: aluminum alloy.If you notice while driving, getting up to about 10 MPH doesn't take much power, and many vehicles can do it at idle. In fact, it is hard to hold some vehicles down to 10 MPH.And, with my Fiat, while it does seem a bit under powered on the Freeway, I've always thought it had excellent 0 to 10 MPH acceleration.It may be that for a standard gasoline powered vehicle with transmission, the engine to wheel power conversion would be close to 50%, or less, giving the original Fiat 500 the equivalent of about 6 HP at the wheels. Direct drive, 1/4 HP to each wheel may give a higher power ratio, perhaps even 100% to the wheels.I have never felt particularly unbalanced in my Fiat 500, although I might consider a different design for a lighter car. I have been thinking of a design for a multi-passenger pedal car, and have thought about a 3 person design with a single person in the middle position, 2 people at the sides, and 3 people across when at capacity.The weakest point on the frame would be the vertical load. Starting, stopping, and turning, it is likely much stronger. It isn't flying over bumps very fast.I've taken a 2wd drive vehicle in some pretty extraordinary places. While there are a few surfaces that one looses traction, I don't worry too much about dry ground. It is the wet mud (not on the moon) that is the biggest problem. Some wheel weight, of course, is good for traction, but a lightweight vehicle would also be much easier to get moving. I probably would have chosen wide paddle tires like a dunebuggy, or perhaps a more aggressive agriculture tread. However, narrow tires can actually get good grip by concentrating the weight in a smaller area.Anyway, I don't see why that vehicle couldn't be able to do a speedy 10 MPH on the moon.
LOL"They had ample power driving a 1500lb mass with a 1hp vehicle?"So, a bit like a horse then?
You can see where one has been driving about and where it is parked ...http://www.nasa.gov/mission_pages/LRO/news/apollo-sites.html [nofollow]http://www.nasa.gov/images/content/584392main_M168000580LR_ap17_area.jpg [nofollow]
On the Moon, the rover only has to support 1/6 of its own weight, plus 1/6 the weight of its heavily-garbed passengers.
The wheels don't have to hold up so much weight on the Moon, so you can make them very much "softer".
I could imagine a structure that could absorb the vertical impact of say tossing a 67 lb of grain on it, by using well designed springs, but would be unable to support 800 lbs of weight applied to the middle of the frame.Assuming a left hand drive, you might instruct your drivers not to do hard right hand turns with a single driver, and no passengers. It wouldn't take much to convince the astronauts that their lives depended on safe driving. They might survive a roll-over, but damage to their spacesuits could be fatal.
Ok,So the astronaut on the moon will act both as a 67 lb weight, and a 400 lb mass.Just sitting on the rover, the astronaut would exert a downward weight of 67 lbs. Going over a bump, however, the astronaut would provide the same resistance to change as a 400 lb mass.That would play both ways.When you go over a bump, it would take essentially the same amount of force to get a wheel airborne as on the Earth. However, it will fall back down 6 times as fast on the Earth.That may give one a strange sense of stability, that the rover would in fact exhibit similar resistance to flipping on the Earth and the moon., although it would be easier to maintain a wheelie on the moon as there would be less force bringing the airborne tire back down. Some things might feel like they were happening in slow motion.
Ok,So the astronaut on the moon will act both as a 67 lb weight, and a 400 lb mass.Just sitting on the rover, the astronaut would exert a downward weight of 67 lbs. Going over a bump, however, the astronaut would provide the same resistance to change as a 400 lb mass.That would play both ways.When you go over a bump, it would take essentially the same amount of force to get a wheel airborne as on the Earth. However, it will fall back down 6 times as fast on the Earth.
The construction:It is often said that if astronauts could not even sit on a Lunar Rover here on Earth because the Rovers were built of such lightweight construction that they "would have collapsed in 1 g if the crew sat on it." (1), and that the " The vehicle could support its own weight on earth, but no more" (2).
... See the two astronauts sitting inside one on Earth at ...sorry, you cannot view external links. To see them, please
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For the lunar rovers, traction in 1/6g is a massive problem to overcome, the vehicles only have approx 250lbs weight on the ground an yet have to propel a 1500lb mass, and to make things more difficult it is a loose surface they have to do this on.
I doubt many of us would want to drive such an unbalanced vehicle over an uneven terrain
Quote from: Anywho on 01/04/2013 01:53:43I doubt many of us would want to drive such an unbalanced vehicle over an uneven terrainwhich is why it takes a lot of selection and several years of intensive training to produce an astronaut.
constantly arguing in the face of overwhelming facts is not just stubbornness, it is borderline mental illness.
Here's the reality: We went to the Moon. PERIOD!We sent rovers to the Moon. PERIOD!The Russians sent a rover to the Moon. PERIOD!We sent and continue to send rovers to Mars. PERIOD!Your arguments are all easily and completely refutable. And don't delude yourself into thinking you are simply being determined or resolute in your assertions; constantly arguing in the face of overwhelming facts is not just stubbornness, it is borderline mental illness.
The vast majority of the Apollo moon footage was faked.
Quote from: KubricksOdyssey on 11/11/2013 22:24:27The vast majority of the Apollo moon footage was faked. Why only fake "the vast majority" ? , either fake it all and don't bother going , or it's real ...http://www.thenakedscientists.com/forum/index.php?topic=27912.msg293914#msg293914 [nofollow]
I'm not saying NASA didnt go to the moon. I am saying the photos NASA released were faked.
It's totally nonsensical to only fake some photos/ films.
Another fake rover pic.40 years ago they never envisioned an internet that would uncover careless mistakes such as re-using the same background slide...
You're shooting yourself in the foot : the hill in the background is lit differently between the two frames and the viewpoint is slightly different too, i.e. not "the same background slide".
Patallax issues aside ...
Case of the magically appearing rovers.
Looking for LRVs ? , here's a link to a picture of one on the moon taken in 2011 ...http://www.nasa.gov/sites/default/files/images/584392main_M168000580LR_ap17_area.jpg [nofollow] [ the "parked" LRV is very close to the right edge of the image]On that image you can also see the tyre tracks it has made on the moon's surface.End of story.
If ektachrome film cannot survive space radiation/magnetic/lunar surface heat extremes ...
If ektachrome film cannot survive space radiation/magnetic/lunar surface heat extremes and SSTV cannot be transmitted 270,000 miles (the length of 30 earths) by a lunar module running on obsolete vacuum tubes and weak Exide batteries, why not fake it, eh?
... call this phenomena the "Kubrick Horizontal"...
RD (or anyone), show me an Apollo 17 photo (with a background) that does not contain a Kubrick Horizontal terrain separation.
Quote from: KubricksOdyssey on 12/11/2013 19:25:12RD (or anyone), show me an Apollo 17 photo (with a background) that does not contain a Kubrick Horizontal terrain separation.Only if you ask nicely and promise never to post in this forum again.
... Surely it must be a simple task to find just ONE photo without the terrain line? Just ONE? How hard can it be to find just ONE?