Author Topic: Were the Lunar Rovers faked?  (Read 270154 times)

Offline ka9q

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Re: Were the Lunar Rovers faked?
« Reply #720 on: April 21, 2013, 08:49:42 AM »
Yeah. On an ordinary EV, engaging reverse while going forward would be one way to do regenerative braking. But the LRV batteries were not rechargeable, so you probably wouldn't want to do that. You'd have to dump your kinetic energy in the brakes.

Offline Noldi400

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Re: Were the Lunar Rovers faked?
« Reply #721 on: April 21, 2013, 10:37:34 AM »
I seem to be missing something. How do you pivot the controller backward to brake if the controller can only be pivoted forward? Are there two different pivot points? How does the driver control which one he pivots the controller around?
I think the difference is that you tilt the controller handle back to drive the motors in reverse, and you "translate" (slide) the entire handle backward without tilting it to engage the brakes.

That was my tentative conclusion - see the blue arrow in the diagram - but I'd like to be sure before I start in on Hunchy.

I seem to be missing something. How do you pivot the controller backward to brake if the controller can only be pivoted forward? Are there two different pivot points? How does the driver control which one he pivots the controller around?
I think the difference is that you tilt the controller handle back to drive the motors in reverse, and you "translate" (slide) the entire handle backward without tilting it to engage the brakes.

...and the inhibit switch stops you inadvertently selecting reverse when applying the brakes.

Must make driving in reverse and braking an interesting exercise in coordination. Of course, they were pretty much all Naval aviators, so it can't have been that challenging.  I think it's interesting that NASA classes the LRV as a spacecraft, which I guess it technically is, even though it can't lift off (well, not very far) from the surface.
"The sane understand that human beings are incapable of sustaining conspiracies on a grand scale, because some of our most defining qualities as a species are... a tendency to panic, and an inability to keep our mouths shut." - Dean Koontz

Offline Tedward

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Re: Were the Lunar Rovers faked?
« Reply #722 on: April 22, 2013, 02:00:05 AM »
Not making a direct comparison but when I first towed a trailer is was completely new and you had to think about reversing (pivot point and which way will it go etc). Also the hitch was braked so that could cause issues so reversing up slopes was fun. They sent me to the far side of the yard and said "practice".

I just saw it as a new set of skills and got quite handy slotting the trailer into the bays allocated etc.

Offline Echnaton

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Re: Were the Lunar Rovers faked?
« Reply #723 on: April 22, 2013, 10:22:00 AM »
The first trailer tow I did was a small RV, which I had to back into a slot that was behind my corner garage.  After entertaining the neighbors for some time, one of them offered to guide me.  That didn't work either so I asked him to do it.   He hit it the first time.  At the next opportunity, I took the trailer to a parking lot and spent hours practicing turning and backing around buckets.  It is a nice skill to have  and the confidence really makes a difference on the road.   I also learned to pay attention when parking for a way out of the spot.  Every trailer is different and short ones are particularly difficult because they jack knife so easily.

As you said, Tedward, it is not a direct comparison, but an example of how new experiences will lead one to appreciate the unsuspected difficulty in doing something new, even when it is a familiar activity that others do every day.  Now put that into novel activity in a completely different environment and it is no wonder that NASA completely misunderstood what was needed to do orbital rendezvous and EVA requirements on the first try.

My new RV (when it arrives) is the same length as the old one but is lighter and we widened the driveway so that the backing path is now fully paved.  Parking should now be a breeze.
« Last Edit: April 22, 2013, 10:28:56 AM by Echnaton »
The sun shone, having no alternative, on the nothing new. —Samuel Beckett

Offline Noldi400

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Re: Were the Lunar Rovers faked?
« Reply #724 on: April 23, 2013, 11:45:58 AM »
Not making a direct comparison but when I first towed a trailer is was completely new and you had to think about reversing (pivot point and which way will it go etc). Also the hitch was braked so that could cause issues so reversing up slopes was fun. They sent me to the far side of the yard and said "practice".

I just saw it as a new set of skills and got quite handy slotting the trailer into the bays allocated etc.

I finally learned the skill by holding the steering wheel at the bottom - then the direction I moved my hand was the direction the rear of the trailer took.
"The sane understand that human beings are incapable of sustaining conspiracies on a grand scale, because some of our most defining qualities as a species are... a tendency to panic, and an inability to keep our mouths shut." - Dean Koontz

Offline Echnaton

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Re: Were the Lunar Rovers faked?
« Reply #725 on: April 23, 2013, 06:18:24 PM »
That is the only way I can do it.  A misplacement of the hand, even on the side of the steering wheel, makes for a disaster.  Or at least more entertaining for those watching.   
The sun shone, having no alternative, on the nothing new. —Samuel Beckett

Offline ka9q

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Re: Were the Lunar Rovers faked?
« Reply #726 on: April 24, 2013, 03:48:34 AM »
I think it's interesting that NASA classes the LRV as a spacecraft, which I guess it technically is, even though it can't lift off (well, not very far) from the surface.
When it comes to the engineering skills required to design it, it does qualify as a spacecraft. The communication system was functionally the same as on the LM. The thermal problems in particular were much like any spacecraft, or even worse since it had to operate not only in a vacuum but on the moon. What's unusual about it among spacecraft is that it had to operate under continuous acceleration, i.e., gravity, rather than weightlessness.

Offline Noldi400

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Re: Were the Lunar Rovers faked?
« Reply #727 on: April 24, 2013, 10:29:36 AM »
I think it's interesting that NASA classes the LRV as a spacecraft, which I guess it technically is, even though it can't lift off (well, not very far) from the surface.
When it comes to the engineering skills required to design it, it does qualify as a spacecraft. The communication system was functionally the same as on the LM. The thermal problems in particular were much like any spacecraft, or even worse since it had to operate not only in a vacuum but on the moon. What's unusual about it among spacecraft is that it had to operate under continuous acceleration, i.e., gravity, rather than weightlessness.

The control panel was more like an aircraft than anything else: pitch, roll, range & bearing. And operated with a control stick.
"The sane understand that human beings are incapable of sustaining conspiracies on a grand scale, because some of our most defining qualities as a species are... a tendency to panic, and an inability to keep our mouths shut." - Dean Koontz

Offline Tedward

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Re: Were the Lunar Rovers faked?
« Reply #728 on: April 29, 2013, 03:05:45 AM »

I finally learned the skill by holding the steering wheel at the bottom - then the direction I moved my hand was the direction the rear of the trailer took.

Never goes away does it. Like learning to ride one of them new fangled falling off machines.

I got a chance to have a go at a HGV (US parlance, truck and trailer? 18 wheeler or whatever?) capable 30+tons with a tractor unit and long trailer. It was off road (old runway) and we had an instructor, cones out for obstacles etc. It had been a few years since I had dealt with a trailer but get your head around the pivot point and I thought I did quite well. Only killed a few traffic cones. The cones were set out as parking bays, road corners etc to get the artic around.


Offline Noldi400

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Re: Were the Lunar Rovers faked?
« Reply #729 on: April 29, 2013, 10:13:50 AM »

I finally learned the skill by holding the steering wheel at the bottom - then the direction I moved my hand was the direction the rear of the trailer took.

Never goes away does it. Like learning to ride one of them new fangled falling off machines.

I got a chance to have a go at a HGV (US parlance, truck and trailer? 18 wheeler or whatever?) capable 30+tons with a tractor unit and long trailer.

Usually "tractor-trailer" or "semi".  "18-wheeler" is used but is more rural slang, generally.  But we're a big country - there's a considerable variation in regional slang dialects.

Never tried one myself although I have a son who drove for Pepsi for a while.  He also says it's similar to a car and trailer once, as you said, you figure out where the pivot point is.
"The sane understand that human beings are incapable of sustaining conspiracies on a grand scale, because some of our most defining qualities as a species are... a tendency to panic, and an inability to keep our mouths shut." - Dean Koontz