hello people!

pls. report navigation system discrepancies, errors and road changes to http://update.navtech.com

let's make an already amazing system much better!

i've submitted 3 reports thus far

 

This company's data and system are not so accurate as Lexus's. Hope it will make system better and better.

Thanks for your info.

 

who does Toyota/Lexus use for their map data?

 

I just hope that I get a more recent database when my car arrives. The database in the dealer's car was over 1 year out-of-date. I'm hoping ... but not expecting.

 

Beg to differ... the lexus nav system in my parent's car is nowhere near accurate as the TL's...

 

Since Navtech has the update, have anyone mailed them and asked if they have the update for Acura model (04TL)?




TO LSIII, sorry, I don't know who is their system designer.




TO sirbrah, yes, you may be right. IMO, in my case, unfortunately I found out Lexus GX470 system sometimes gives me more verified roads and accuracy when driving out of town and staying in the coutrysides. In the city, when I approaching the intersections, TL displays I'm dozens of feet away from that intersection, but that Lexus system shows I'm just right on that intersection.

 

The July version is the most recent. The Oct version is for non-voice rec. units.

I too am disappointed with how old the maps are. My neighborhood is 3 years old and NOT on the map.

 

In the city, when I approaching the intersections, TL displays I'm dozens of feet away from that intersection, but that Lexus system shows I'm just right on that intersection. [/B][/QUOTE]

MIne was doing the same. But that can be adjusted by going into the "setup" screen and hitting option page 4, then "vehicle position".

 

Thanks, I'm aware of that setup, however, am lacking in confidence in doing so.

 

My neighborhood is 11 years old.

When I was driving home for the first time after picking up the car, it told me my house was the right side when indeed it was on the left. I don't know how it got confused!

 

It's all to do with mandatory graduation policies at the factory.
You will come across some cars that get left & right confused.
Some will not be able to do 3rd grade math.
Some will just rattle.

Just be thankful you only got one of they dyslexic ones.
<VBG>

 

That's absolutely unacceptable! I want them to send my car back to remedial school so it:

1) knows the difference between left and right
2) Stops rattling. Put a pacifier in it already!

 

So far as I know, EVERY factory installed GPS unit in the US uses NAVTECH maps. I am certain that they have different versions and that it probably costs the manufacturer a certain amount per update to start using the newer maps, but I am also fairly certain that we have the latest maps available.

I find that I am often "off" at the same intersection, everytime. Others are right on. So, I assume that it is the map that is off, or, perhaps, due to tree cover, the satellite data in that spot is not 100%. I don't know. I have found, when it is correct, that it is the tip of the "arrow" that is the poistion of the GPS sensor, which, I think, is in the back of the car. I've also noticed a very slight delay when you are moving at a good speed.

Lately, I've noticed that my calibration on the dead reckoning system seems to be off. I don't know why, as I've done nothing to change it. Sometimes the Yaw sensor seems off too. On the map, I'm way off base, sometimes heading in the wrong direction, for quite sometime after the GPS notation goes green, so I don't know how the dead recokoning system interacts with the GPS data. That could also cause us to be off sometimes.

 

I followed the above listed info about correcting the position on the nav screen. I could change rotation, but not position. I could move my position arrow on the setup screen, but it would revert back on the main screen, usually 30 feet behind an intersection as I enter it. My home (been here 100 years) is not listed on the map, my neighbors (20-30) years are. Our Costco of about 6 years is also not listed. My Garman StreetPilot III has more accurate maps and locations, but is more difficult to use and has a small screen. I hope for updated maps, but the Nav system has a great screen, is very user friendly, and I am still glad I got it.

 

Hello? NavTech has 100% market share in navigation data in the US.

 

IMO, I wish I miss something 'cause they don't list all makers... where are Lexus & Infiniti? Thanks...



Acura
Alpine
Avis
BCI
Becker
BMW
Citroën
Clarion AutoPC
Denso
Digital DJ
Fujitsu Ten
Hertz
Heusch/Boesefeldt
InfoGation
Jaguar
Land Rover
Magellan Magneti Marelli
Motorola
Navi PC
Oldsmobile
OnStar
Peugeot
Pioneer
Porsche
Pronounced Technology
Renault
Siemens
TECmobility
Trimble
VDO Dayton
Visteon
Volvo
Zenrin


Maybe, they can say those companies above use their DATA and SOFTWARE together. And, other car makers just use their DATA.

I saw this, too.
Every vehicle navigation system in North America and the majority of vehicle navigation systems in Europe that offer turn-by-turn route guidance use NAVTECH data. Navigation systems provide route planning information and turn-by-turn guidance via an LCD screen and easy-to-understand voice prompts that advise drivers of approaching turns.

 

Basically, the problems you are seeing can stem from two sources: GPS accuracy, and software implementation.

Originally, GPS accuracy was limited by the US government to approximately 100 m (approx. 300 ft) of error by using a system called SA (Selective Availability). However, the commercial industry developed DGPS, or differential GPS which lowered the error down to about 10 m (30 ft), which made hand-held GPS systems usable by the public. Eventually, the SA error was turned off (around 1990, I believe).

Depending on how Alpine's software is designed, it may display the actual car's position with greater (or less) accuracy. I have used multiple GPS navigation packages on my PDA, and some display my postion with greater errors than others. I am always using the same GPS receiver, so it isn't a hardware issue.

For example, if the GPS receiver is in the back of the car, and Alpine decides to always display "true position" (the easiest software solution), your displayed position will always lag behind what you see out of the front of your car. If Alpine decides to do a little more prediction based on your current speed and direction you are heading - combined with you sticking to the road you are currently on - Alpine can give a more accurate position representation most of the time. This is much more complex in software, and can occasionally display your postition less accurately. This latter solution is usually preferred by most drivers, though (like me!).

żGotJazz?

 

Well said.

I always believe most of faults are from the software since we share the same satellites over the sky.

 

i also have the "late" navi syndrome, it seems to be constantly behind a good 30 ft like when crossing an intersection, what's weird is that i didnt notice it the first time i drove the car, it was dead perfect the 1st time, i hope it doesnt get worse from here...

that's exactly what i mean, guys, report your missing neighborhood, street or what have you so we can make this thing better and get our money's worth in the disc upgrades....if you want to see your neighborhood or the street where you live at then i suggest you go to http://update.navtech.com

thanks people

 

zeicht - what are we supposed to put in the fields on the update site for the DVD Version and System Brand?

 

Look at my gallery, its 1.03 I believe. I have a screen of the latest Navi software. Funny they don't have Ontario on yet, I just let them know.

 

Acura GPS units are not that accurate.

 

Almost all GPS receivers today can pick up and process a maximum of 12 satellites simultaneously. With today's DGPS technology, all GPS units have basically the same "accuracy", somewhere around 10-30 feet of error. How the software handles it is the question.

For example, let's say that the Alpine system actually displays the unmodified GPS position (which it doesn't), and it has the worst accuracy (30 feet). The 30 feet of error is random - sometimes it would be ahead of you, sometimes behind you ... AND sometimes to either of your sides. If you are on a two-lane road, do you see the displayed position switch into the opposing traffic lane?

I doubt that you'll ever see that happen, because Alpine's software applies "stickiness" to your current road and direction, assuming that you won't usually go 4-wheeling in your vehicle. For car navigation systems, the only places that you can travel on are the roads in the database. Anywhere else gets the system a little confused.

Since the software assumes that you are going to keep heading on the road that you are currently on, it can be programmed to make your display more accurate. For example, the software can perform calculus equations on your GPS data to determine instantaneous velocity, acceleration, and jerk. These values can feed into other equations to try and "predict" where your car actually is on the road.

Why can't it just put your displayed car position at the GPS position it gets from the satellite with just minor adjustments? Why does it need to "predict"? The answer is simple - economics. If Alpine didn't care about the cost of the Navi systems (or their profit margins), they could put in the latest 2-3 GHz processors with tons-o-memory into each GPS system and do just that. However, Alpine likes to make money. If they can shave $10 off of the final production costs each of the Navi systems, and they are selling 100,000 per year - that directly translates into 1 million dollars of extra profit at the end of the year. So, the Navi system has a cheaper processor (maybe somewhere around 400 MHz to 1 GHz), and whatever memory they need to just get by. With reading the DVD data, processing the GPS data, constantly updating the 2 dimentional (or sometimes 3 dimentional) displays, interpreting audio commands, and a few thousand other things I didn't mention, the processor is really busy. So, your displayed GPS position and the display itself has a tendancy to lag reality by a little bit.

To compensate for the inherent delays and errors in the display, the software can try to predict what your position is going to be when you see it on your display. These software algorithms are complex and proprietary information for the companies (like Alpine) that generate them. Some companies do a much better job than others.

Apparently, Alpine has room for improvement in their software.

żGotJazz?

 

FYI... I took delivery last week and my version is 1.04 dated 9/2003.

 

Ooh! Ooh! I want the new version. We should get a free upgrade (ha! ha!)

Wonder what's updated from 1.03.

 

That is awesome! I just hope that it is recent enough to include the newer highway changes that occured in my area within the last year.

 

I guess it's not having a dramatic change with it. 1.04 vs 1.03, 200309 vs 200307. But the truth is to keep your map always updated and accurate.

Anyway, I have an appointment on Monday morning and am going to ask my dealer if they can swap or update my DVD...

If it's really having tons of update, I'd sneakingly swap my DVD with their Demo car in the showroom.



kona, thanks for your Info. Do you mind telling us your possible VIN range and built-date?

 

OK, I'm not so excited now.

żGotJazz?

 

well i just put in 200307 (the date) for the dvd version and acura in the system brand field...i forgot the version no. and didnt bother to look anymore as i remember the date version...

i just gave anonymous info in the required fields...

 

i adjusted the position of the vehicle cursor in the setup screen 4 with the joystick and for a moment the cursor seems right on but after a few seconds of driving reverted back to being "late"...... i guess there's no way to override the position of the cursor

 

Sure there is. Just follow these simple steps:

(1) Locate where the GPS module is in the TL.

(2) Remove module, noting wire connections.

(3) Go to your Acura dealer and purchase 2-3 cans of spray-paint matching your TL color.

(4) Go to Home Depot and buy the following:

- approximately 30 ft. of extra wire for each attached wire to GPS module.
- Welding mask
- Welding torch
- 35 ft. of 3 inch square stainless steel rod

(5) Attach 30 ft of wires to the GPS module.

(6) Weld 5 feet of the stainless steel rod to the roof of your TL, with 30 ft of rod hanging in front of your car

(7) Weld GPS module to the forward end of the rod.

(8) Carefully apply paint and clearcoat to the rod & car to get that "professionally-installed" look.

Problem solved.

Notes:

1. This installation may affect your stopping distances.
2. If you try this, let us know your results. Also, be sure to let us know where you live and when you'll be driving, so that we know to what city to avoid to stay away from your crazy-@ss.



żGotJazz?

 

Are you claiming that the Acura TL's nav system uses DGPS?

 

I really don't know if the Acura uses DGPS.

But since the Selective Availability (SA) error signal was turned off by order of President Clinton back in the 90's, we probably don't really need DGPS - unless we go to war inside the borders of the US. At that point, we probably won't be as concerned with the accuacy of our Navi systems. I know that non-DGPS receievers have an error of up to 30 feet (for the ones I researched from Magellan, Garmin, and Holux).

 

I have paid some careful attention to car's position vis-a-vis intersections the last two days. Here is what I found. Note, in all cases I had a green GPS indicator, showing a 3-D satellite lock).

When going home, I have to come up a mile long hill with lots of side roads. As I go up that hill, I get further and further behind my real position, until I am almost a full intersection behind. When I go back to work in the morning, I am still behind, though not as far, and I am going down the hill. The distance off and the direction off for any given position/direction traveled is consistent from day to day. Also, I can stop at an intersection, and the navi does not "catch up" more than a tiny bit.

This tells me some things. First, it tells me that the maps are not at fault. Why? Because the Nav is behind the actual position going either way. If the map was off, I'd be behind going one way and in front going the other. Second, this is not a dilution of precision problem, at least not by itself. If it were, I would randomly be behind some times, and ahead other times. Third, I don't think it is a problem with the system not being able to keep up. I am only going 30-35 MPH here, and I've seen it keep up at much higher speeds on the highway. Further, if this were the issue, should it not "catch-up" at the stop sign.

This is a tree covered road, at least to the south. So I think the issue may relate to satellite data. I also tend to be in this area early in the morning going and in the evening coming, so this could also result in satellite and error issues. I suspect at least part of the problem is the interplay between the dead reckonning system and the satellite data (perhaps this it he fault of teh EL-42's also ).

I watched all the way into work today, and I noted that after the "bad zone" on that hill, I was either right on or within an acceptable range, sometimes a bit ahead and sometimes a bit behind (more often behind, but most often right on). I did notice that the front of the "arrow" is the position indicator, and that it appeared to mark the trunk of the car, rather than the front. I can't imagine, however, that any non-military GPS could be so accurate as to show the actual part of the car containging the antenna.

Any thoughts?

 

Yup. It's not satellite data. The satellites aren't really sending you lots of data, and they don't know anything about where you are at. Remember, these satellites are sending information to many thousands of GPS receivers in the world simultaneously.

The best way to think about the GPS satellite network is to view them as precision timepieces orbiting the planet. Each of the 24 functioning (and 3 spare) satellites tells us which satellite number it is and information that gives a very precise time reference (and a few other pieces of data). Since the satellites are always moving in reference to your location (they are not in geosynchronous orbit), the distance they are away from you is constantly changing. The precise time reference allows the receiver to calculate how far away each satellite is from your position.

Once you are receiving data from 4 or more satellites, you can determine your location and altitude by doing a moderately complex calculation called "trilateration".

These calculations are all done with software by the Alpine GPS system, and some software stored in the GPS receiver itself. Keep in mind that the GPS receiver is usually a seperate device with its own embedded software (kind of like a smart radio antenna) that sends GPS data to the Alpine GPS system.

So, I still contend that all the problems people are complaining about are with the Alpine GPS system's processing software, not the satellite data.

I've seen excellent position tracking with my PDA / Holux GPS receiver. I've also seen lousy tracking with the same hardware. The only difference is the processing software package on my PDA.

If you're interested, you can read more about how GPS works here: How GPS Works.

Cheers!

 

Your science is right on.
BTW, I have found that with the latest disc the speed of calculation has slowed to the point that turn instructions have been late and I have missed intersections as a result. :wow: This would be a software issue because this was never the case with previous versions.

 

After you reposition the marker, push the joystick in to lock in the new position. However, I must confess, I can't seem to make my new location permanent either. It seems to last for the rest of that particular trip (at best) but is back "behind the intersection" next time I drive the car. Interesting that it happens only on some intersections, while others are dead on. I would tend to think it's a map issue (as suggested earlier).

 

Once again, thanks for your info.

After speaking with the dealer, ACS, and Acura Navi DVD hotline, 888-549-3798, Acura uses the same data DVD for 04TL Navi. Whenever your TLs are built or whatever versions your DVD say, they are the same.

Thus, 200307-1.03 and 200309-1.04 actually are identical.

 

żGotJazz? -- I finally got started on welding the modified antenna to my truck. I dont have my TL yet, but I figured I'd practice with my F150. Anyhow I'm extremely dissapointed with the reception. Seems my GPS is off like 20 miles or so...

Seriously you've got some seriously good posts here. Seems you know your s**t. Kudo's to you.

For the rest of you -- enjoy your GPS. Sure theres some problems, but you gotta admit, that pretty screen is sure nice looking at!!!

 

greenseed, fasTLane, rets, and others -

Thanks for the kind words! I'm not always sure if anybody's really reading my stuff.

As you've probably guessed, I'm an engineer by day ... and soon to be an 04TL racecar driver by night (only 6 weeks to go ...). I'm glad that I can share some of the stuff I've learned wih you guys. I know that I've learned quite a bit from this forum since joining.

BTW, my friends say that I'm "a virtual cesspool of information"!
It comes in handy during a game of Trivial Pursuit!

Cheers!