OpenStreetMap 開放街圖
After having my bike stolen, its been a while since I did some mapping. The new one is much better anyway, so am trying to get on it as much as possible in between the rubbish weather we're having.
My first attempt on Monday was rather disappointing though. The GPS data I got was completely wrong and traces showed me travelling through large buildings and rivers...
討論
由 slashme 於 2009年11月 5日 19時07分 發表的評論
Bike mapping is good fun: gets you close to the ground and the exercise is nice. One can still miss some small details on a bike, though: are you sure you didn't travel through some buildings and large rivers and just not notice?
由 Steeley 於 2009年11月 5日 19時15分 發表的評論
Nope, definitely didn't travel through the buildings the GPS data said I did.
I'm not sure if it had something to do with the clocks going back an hour this past weekend and the GPS being incorrect. The only other possibility I can think of is a poor signal in the area that day.
由 Baloo Uriza 於 2009年11月 5日 19時20分 發表的評論
GPS uses UTC, which doesn't deal with obsolete concepts such as daylight savings time at all.
由 harfner 於 2009年11月 6日 07時02分 發表的評論
I have had GPS traces displaced for some hundred meters occasionally with a my Holux M241, which generally works well.
I've got the impression that sometimes the first fix after switching on goes wrong. Switching on the unit in a free space far away from buildings might help.
GPS does knew nothing about daylight saving time, that's not an isssue.
由 daveemtb 於 2009年11月 7日 00時16分 發表的評論
Could it be to do with how you are carrying the GPS? It needs to have a clear view of the sky and I've found that it took a bit of experimentation when cycling to find a good arrangement. Putting it in the back pocket of my bag didn't work as well as I expected.
由 Steeley 於 2009年11月 7日 11時35分 發表的評論
I've done quite a few trips with it and its never been a problem just having it in my pocket. The GPS also picks up a signal in the house with no problems.
I'm going to just put it down to one of those days.