Me too, plus tintlarry.contrisciano wrote:Hi,
I have a M35 sport, with Journey and Tech package. I have no complaints about the car at all. ljc
Satellite navigation, just like other navigational instruments, base accuracy on triangulation, in this case, of more than 2 satellite positions. In laymans terms, accuracy is best on 2 satellites 90 degrees apart, 3 satellites 180 degress apart, etc. Fixing satellites are also 3 dimensional so it's altitude affects accuracy as well. Anything that blocks satellite signals e.g. tall buildings, mountains, etc. are another factor. Last. Just like any computers, sat. navs are prone to error caused by low memory, power fluctuations, etc.{-===-} wrote:I have the M45 Sport w/Journey & Technology package, Only things I don't like is the navigation is not accurate sometimes and the paint on the car is too soft.
Good observations! Thanks.Edong t5 wrote:Satellite navigation, just like other navigational instruments, base accuracy on triangulation, in this case, of more than 2 satellite positions. In laymans terms, accuracy is best on 2 satellites 90 degrees apart, 3 satellites 180 degress apart, etc. Fixing satellites are also 3 dimensional so it's altitude affects accuracy as well. Anything that blocks satellite signals e.g. tall buildings, mountains, etc. are another factor. Last. Just like any computers, sat. navs are prone to error caused by low memory, power fluctuations, etc.
I've worked with sat. navs way in merchant ships way before they became available to consumers during the early 80's. This navigational instruments are so accurate then that it has simplified conventional navigation and help concentrate our efforts more on traffic and safety. Unfortunately, that hasn't prevent Exxon Valdez running aground up in Alaska. Sat. navs have gone a long way in terms of application and accuracy. Saying that, its the person behind the wheel that's gonna' make a diifference to make that tool (which is just what is) work for him.szhosain wrote:
Good observations! Thanks.
The place where I work is in the business of providing long-range data transport services to navigation equipment and I can assure you all that nothing is perfect in the Nav world - the M45 is not any worse than the others at all! I speak from real experience with my boss's Q45 that has the same Infiniti system, compared to the forty or fifty GPS-tracking application customer companies that we have.
The theoretical limits to GPS-based tracking are a lot better than practical reality, of course! Regardless, the Nav systems do remarkably well, given all the possible ways that they can mess up. Three or four good satellites in view will work wonders for accuracy - the good GPS units can use up to 10 or 12 satellites for their fixes (not that many can possibly be visible simultaneously though.)
If anyone wants any technical links or book references on GPS for more reading (or to put them to sleep at night), let me know!
Z
Cool stuff!Edong t5 wrote:I've worked with sat. navs way in merchant ships way before they became available to consumers during the early 80's. This navigational instruments are so accurate then that it has simplified conventional navigation and help concentrate our efforts more on traffic and safety. Unfortunately, that hasn't prevent Exxon Valdez running aground up in Alaska.
That's very interesting. There's a container port in Hamburg, Germany right now that's equipped with robotic trailers picking up containers guided by sat. nav. It runs 24 hours and can unload/load container ships in one day. It only requires 2 people to operate and all they do is watch the monitors to make sure everything is running without problems. US container ports are going to be upgraded with the same technology soon. I won't be surprised if your company will be part of this modernization process.szhosain wrote:
Cool stuff!
Fortunately, GPS navigation on open water is a lot easier than in urban canyons and inside buildings! Some of the problems we work on require differential GPS corrections, for example. One application controls equipment in farm land for automated no-human-contact farming (plowing and crop harvesting) ... no room for error there!
Z
I was navigation officer in one of Exxons tanker based in Rotterdam till '89. My experience with sat. navs. is only application. Back then, they're the size of a 20 inch monitor and will only give you latitude and longitude, no maps, nothing. That's why I'm still amazed at my portable magellan sat. nav., almost the size of my hand, containing the map of the whole US mainland. What kind of business does your company engage. I realize you're based in San Jose, so I'm guessing it's more on software than hardware.szhosain wrote:Where do you work, by the way? Sounds like really interesting stuff!
Z