Environment display

[andpotti]

Sorry if this has been covered elsewhere (can't find any info) Can I calibrate the barometer/altimeter any way, it doesn't seem to be that active?? really annoying.

 

[EVkris]

Is there an altimeter? Where can I find that info?

 

[andpotti]

Info- environment on screen

 

[maby]

I don't think there is any calibrate function - have looked. I'm not sure it would be that much use - what would you use as a reference point in everyday use?

 

[CJ1045]

Drive to the seaside? Or OS map?

CJ

 

[maby]

Drive to the seaside? Or OS map?

CJ

That would, of course, work - but are you really going to do it? Do remember that this is not a one-off thing if you are thinking of calibrating the altimeter - you have to do it every day, possibly multiple times per day.

 

[tjacobsen]

Hi Guys

I seriously doubt that a) it's a barometer function and b) that it can be calibrated in any way
the data is most likely provided by the GPS receiver, and although the GPS can measure very precisely the display rounds up/down to the nearest 10m (at least in my car)
giving you a false sense of inactivity if you drive around in relatively flat terrain

 

[maby]

Hi Guys

I seriously doubt that a) it's a barometer function and b) that it can be calibrated in any way
the data is most likely provided by the GPS receiver, and although the GPS can measure very precisely the display rounds up/down to the nearest 10m (at least in my car)

I'm pretty sure it is a barometer for two reasons:

1. the altitude display is on the same screen as the barometer display
2. I have a barometer on my smart phone which can also display estimated altitude based on barometric pressure. The altitude displayed on the Outlander MMCS with the car parked outside my house is always very close to the uncorrected altitude displayed on my smartphone.

 

[tjacobsen]

Hi Guys

I seriously doubt that a) it's a barometer function and b) that it can be calibrated in any way
the data is most likely provided by the GPS receiver, and although the GPS can measure very precisely the display rounds up/down to the nearest 10m (at least in my car)

I'm pretty sure it is a barometer for two reasons:

1. the altitude display is on the same screen as the barometer display
2. I have a barometer on my smart phone which can also display estimated altitude based on barometric pressure. The altitude displayed on the Outlander MMCS with the car parked outside my house is always very close to the uncorrected altitude displayed on my smartphone.

To me this sounds a bit weird, a GPS (even in civilian version) is very accurate, and a barometer is not (when used for map referencing) as it needs to be calibrated to display the correct altitude. so why would you use a unreliable sensor technology which is affected by weather and all sorts of other environmental issues instead of using a simple GPS signal?

I will try to test my theory later today, I'm driving to the mountains and there are a few tunnels on an incline, given that the car looses the GPS signal in the tunnels the altimeter should remain stationary and jump up/down ehn I come out of the tunnel. (if it's not linked to the maps and adjusts the altitude in accordance to the map info)

 

[maby]

GPS altitude is not particularly accurate, you know - see http://gpsinformation.net/main/altitude.htm.

It is a lot more accurate in the horizontal plane, but even then it is a fair bit less accurate than we like to think - there are a variety of trick that the receiver plays to improve it. Those tricks don't work so well in the vertical plane and some of them, like snap-to-map, don't work at all. There is still a big question mark over whether or not the Outlander GPS can use EGNOS - initially I thought so, but viewing the GPS status screen, I'm coming to the conclusion that it probably does not. If that is the case, then the GPS altitude figure will be even more unreliable.

 

[tjacobsen]

hmmm makes you wonder.
it's not what they told us at school and in the Navy but then again I have learned that not all they told was 100% true..
looking forward to testing my theory in the tunnels later today, will try to post results tomorrow if time permits.

 

[maby]

hmmm makes you wonder.
it's not what they told us at school and in the Navy but then again I have learned that not all they told was 100% true..
looking forward to testing my theory in the tunnels later today, will try to post results tomorrow if time permits.

The navy is not that worried about altitude, you know! Aircraft still use barometric pressure as an important source of altitude data. Every airfield and airport broadcasts accurate and up-to-date values for air pressure at ground level to allow aircraft to calibrate.

 

[roseytony]

Hi Guys

I seriously doubt that a) it's a barometer function and b) that it can be calibrated in any way
the data is most likely provided by the GPS receiver, and although the GPS can measure very precisely the display rounds up/down to the nearest 10m (at least in my car)
giving you a false sense of inactivity if you drive around in relatively flat terrain

Hi,

I suspect that it is nothing to do with the GPS. My previous car - a Mitsubishi L200 - also had Barometer and Altitude readouts and that had no GPS.

Cheers

Tony

 

[maby]

I'm now parked about 10 feet above sea level and the altimeter reads 350 feet. On my journey from Hertfordshire to Kent, I kept an eye on the display snd altitude followed barometric pressure pretty rigidly, so I'm convinced that it is based on air pressure. If it's GPS based, it's a terrible chipset because it was consistently over reading by several hundred feet all the way round the M25. Pressure is low, by the way - 999 millibars according to the instruments on the boat.

 

[tjacobsen]

I stand corrected, the display did not change in the tunnels when the car lost the sat signals.
I also noticed that it rounds up to the nearest 50m not 10m as I remembered.. all in all pretty inaccurate and more a toy as opposed to real data display.
the other car we have that has an altitude display function has a far more precise readout and as far as I can tell doesn't round up at all and is pretty consistent on the elevation of the house and a few other places that we visit regularly (and where I bothered to check)

 

[maby]

I think I would have preferred that the graph showed pressure rather than an attempt at altitude - that would have some value for weather forecasting.

I guess that the rounding up is a recognition that the accuracy will not support better without frequent recalibration.

 

[gwatpe]

Have had the opportunity to see how my PHEV worked with the environment display. Seems to show the height, but about half an hour lagged. The graph must be behind part of the map border. Went over a mountain range and eventually saw the trace go up and then down well after we were 30 or more km down the road. Bit pointless really even having it shown here. Maybe it should be in one of the history pages rather than the real time window.

Suspect the data comes from the GPS and not a sensor in the car. Is part of the MMCS and not on the dash screens.

 

[maby]

Have had the opportunity to see how my PHEV worked with the environment display. Seems to show the height, but about half an hour lagged. The graph must be behind part of the map border. Went over a mountain range and eventually saw the trace go up and then down well after we were 30 or more km down the road. Bit pointless really even having it shown here. Maybe it should be in one of the history pages rather than the real time window.

Suspect the data comes from the GPS and not a sensor in the car. Is part of the MMCS and not on the dash screens.

It really is not linked to the GPS - I've been monitoring it and the declared altitude of my drive outside the house goes up and down linked exactly to air pressure. It seems to be calibrated to a standard sea-level air pressure of about 1013 mBar - pretty much the standard - keep an eye on your barometer and check what the MMCS says your altitude is.

 

[gwatpe]

Either way, I still see no reason why there is such a delay in the update of the displayed height relative to the position the car has traveled to. Is not very useful while travelling, and so has no reason to be displayed in any section but the history. Putting something more useful on that screen would be a start.

 

[maby]

Either way, I still see no reason why there is such a delay in the update of the displayed height relative to the position the car has traveled to. Is not very useful while travelling, and so has no reason to be displayed in any section but the history. Putting something more useful on that screen would be a start.

I would certainly prefer that the graph should show air pressure - useful for weather trending - and they are welcome to put a single digital field that estimates altitude. I know that the graph effectively displays inverse air pressure, but the scale makes it meaningless