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#11
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Project GALILEO
In article ,
Michael Smith wrote: I think that most Americans who have heard of Galileo are surprised that the Europeans are bothering to fund it. They see it as a free service to anybody, so why develop a competing system? Partly because the Americans have an unfortunate history of deciding that services which are officially available to "anybody" should really be available only to people the US happens to approve of this week. Europe has gotten burned several times by relying on US assurances of that sort, and has decided that it can no longer depend on them. Other countries, including Europe, see global positioning primarily as an important military asset, and would prefer to have their own system for that reason. Actually, the major country of that sort is the US, which is adamant that nobody except the US military controls GPS. There are lots of pious proclamations about how everyone is welcome to use it, but when anyone asks about joint control, so that non-US-military users can have a voice in how it's run and thus some real *assurance* of availability, the answer is always "absolutely not, we make all the decisions, go away". The European nations would probably have been perfectly happy to be international partners in a jointly-run GPS system. But they are not prepared to leave (e.g.) their civilian air traffic at the mercy of someone else's military bureaucrats. -- MOST launched 1015 EDT 30 June, separated 1046, | Henry Spencer first ground-station pass 1651, all nominal! | |
#12
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Project GALILEO
"Dr. O" dr.o@xxxxx wrote:
Galileo is however, not a military system, but can be used for military purposes, both by US friendly nations (such as the European NATO partners) but more importantly, also by unfriendly nations (or at least adversaries). That last point is the reason why the US is against Galileo. Why? Because Galileo is guaranteed to operate even in times of war (whist GPS isn't). That means that it's suitable for things like auto-navigation/auto-piloting of aircraft and cars. Since GPS is switched off or into 'low-resolution' mode during conflict, it can't be relied upon for critical tasks. Fact is, those 'critical tasks' are few, and none are without backup. Very few of them are actually 'critical'. D. -- The STS-107 Columbia Loss FAQ can be found at the following URLs: Text-Only Version: http://www.io.com/~o_m/columbia_loss_faq.html Enhanced HTML Version: http://www.io.com/~o_m/columbia_loss_faq_x.html Corrections, comments, and additions should be e-mailed to , as well as posted to sci.space.history and sci.space.shuttle for discussion. |
#13
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Project GALILEO
"Derek Lyons" wrote in message ... "Dr. O" dr.o@xxxxx wrote: Galileo is however, not a military system, but can be used for military purposes, both by US friendly nations (such as the European NATO partners) but more importantly, also by unfriendly nations (or at least adversaries). That last point is the reason why the US is against Galileo. Why? Because Galileo is guaranteed to operate even in times of war (whist GPS isn't). That means that it's suitable for things like auto-navigation/auto-piloting of aircraft and cars. Since GPS is switched off or into 'low-resolution' mode during conflict, it can't be relied upon for critical tasks. Fact is, those 'critical tasks' are few, and none are without backup. Very few of them are actually 'critical'. Automatic guidance/piloting of commercial aeroplanes will require less than 1m of resolution at all times. Such as system would be impossible to do with GPS and I don't think a backup system based on inertial guidance in conjunction with radio-beacon navigation would work. |
#14
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Project GALILEO
"Dr. O" dr.o@xxxxx wrote:
"Derek Lyons" wrote in message ... "Dr. O" dr.o@xxxxx wrote: Since GPS is switched off or into 'low-resolution' mode during conflict, it can't be relied upon for critical tasks. Fact is, those 'critical tasks' are few, and none are without backup. Very few of them are actually 'critical'. Automatic guidance/piloting of commercial aeroplanes will require less than 1m of resolution at all times. Odd then that automatic pilots have been around for decades, and widely used, despite not having an accuracy anywhere near that level. (That requirement arises primarily from technocrats who refuse to adopt an efficient solution, preferring a technological one that not only pushes the need to solve the problem out a generation or two, but introduces many new modes of failure as a bonus.) Such as system would be impossible to do with GPS and I don't think a backup system based on inertial guidance in conjunction with radio-beacon navigation would work. It's quite possible to do with differential GPS, even in degraded mode. D. -- The STS-107 Columbia Loss FAQ can be found at the following URLs: Text-Only Version: http://www.io.com/~o_m/columbia_loss_faq.html Enhanced HTML Version: http://www.io.com/~o_m/columbia_loss_faq_x.html Corrections, comments, and additions should be e-mailed to , as well as posted to sci.space.history and sci.space.shuttle for discussion. |
#15
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Project GALILEO
"Derek Lyons" wrote in message ... "Dr. O" dr.o@xxxxx wrote: "Derek Lyons" wrote in message ... "Dr. O" dr.o@xxxxx wrote: Since GPS is switched off or into 'low-resolution' mode during conflict, it can't be relied upon for critical tasks. Fact is, those 'critical tasks' are few, and none are without backup. Very few of them are actually 'critical'. Automatic guidance/piloting of commercial aeroplanes will require less than 1m of resolution at all times. Odd then that automatic pilots have been around for decades, and widely used, despite not having an accuracy anywhere near that level. (That requirement arises primarily from technocrats who refuse to adopt an efficient solution, preferring a technological one that not only pushes the need to solve the problem out a generation or two, but introduces many new modes of failure as a bonus.) Not if you want the entire flight to be automatic, including takeoff and landing and taxiing. Also, I'll bet that any new system will need to increase the airtraffic capacity markedly, which means more planes per square mile, thus better accuracy. Such as system would be impossible to do with GPS and I don't think a backup system based on inertial guidance in conjunction with radio-beacon navigation would work. It's quite possible to do with differential GPS, even in degraded mode. Automatic car guidance (ACG) is another system which needs greater accuracy plus 24/7 operation, regardless of the political situation in the world. If the U.S. insists on crippling its GPS system its going to lose out in some huge markets. A system such as ACG cannot function without Galileo and Diff-GPS would be way too expensive. |
#16
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Project GALILEO
"Dr. O" dr.o@xxxxx wrote in message .. .
Automatic car guidance (ACG) is another system which needs greater accuracy plus 24/7 operation, regardless of the political situation in the world. If the U.S. insists on crippling its GPS system its going to lose out in some huge markets. A system such as ACG cannot function without Galileo and Diff-GPS would be way too expensive. Automated car guidance requires very detailed environment sensing, so as not to run into traffic cones, debris in the road, pedestrians, animals, stopped or wrecked cars, and the like. Given that you need that much local perception in the automatically guided car, ordinary GPS will probably do just fine. -jake |
#17
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Project GALILEO
"Jake McGuire" wrote in message om... "Dr. O" dr.o@xxxxx wrote in message .. . Automatic car guidance (ACG) is another system which needs greater accuracy plus 24/7 operation, regardless of the political situation in the world. If the U.S. insists on crippling its GPS system its going to lose out in some huge markets. A system such as ACG cannot function without Galileo and Diff-GPS would be way too expensive. Automated car guidance requires very detailed environment sensing, so as not to run into traffic cones, debris in the road, pedestrians, animals, stopped or wrecked cars, and the like. Given that you need that much local perception in the automatically guided car, ordinary GPS will probably do just fine. I don't think so. Perception of the environment can be done with current radar technology. None of the ACG systems demonstrated so far use GPS. All of them use Diff-GPS. |
#18
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Project GALILEO
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#19
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Project GALILEO
"Dr. O" dr.o@xxxxx wrote in message ...
"Derek Lyons" wrote in message ... "Dr. O" dr.o@xxxxx wrote: Galileo is however, not a military system, but can be used for military purposes, both by US friendly nations (such as the European NATO partners) but more importantly, also by unfriendly nations (or at least adversaries). That last point is the reason why the US is against Galileo. Why? Because Galileo is guaranteed to operate even in times of war (whist GPS isn't). That means that it's suitable for things like auto-navigation/auto-piloting of aircraft and cars. Since GPS is switched off or into 'low-resolution' mode during conflict, it can't be relied upon for critical tasks. Fact is, those 'critical tasks' are few, and none are without backup. Very few of them are actually 'critical'. Automatic guidance/piloting of commercial aeroplanes will require less than 1m of resolution at all times. Such as system would be impossible to do with GPS and I don't think a backup system based on inertial guidance in conjunction with radio-beacon navigation would work. Road User Charging is a near term application that could be problematic if based purely on GPS. Road User Charging needs to work 100% of the time, and requires a fair degree of accuracy - which GPS struggles to provide even when working. On the other hand, if say, Britain were involved in a mini war in a far part of the world, it might be useful to have GPS denied to the enemy. There would be more chance of the Pentagon helping out than a European committee requiring unanomous voting. |
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