Segue: An old business associate of Larrie's, who was an actuary joked that when he traveled by plane (this was in the mid-1970's), he took his own bomb. He claimed that the odds of two people having a bomb on the same plane were astronomical; therefore, he was assuring a safe trip. Quite possibley, and for the same reason, it is necessary to have two GPS on a ride; however, with our group it also requires a GPS enabled iPhone to even out the odds of a safe return. End seque.
Larrie spent the week of June 7-14 creating a new track and vetting it both on the ground and with others in the group. The goal was to get to a eucalyptus forest that is East of the train tracks and the object of the January 18 ride. Using Google Earth, a gross track was laid out, and then the details were filled in. A total of 348 points were plotted using Google Earth, which should have provided sufficient details to assure a leisurely ride; however, a cautionary note about online imagery - it's old, and we humans continue to shape our environment constantly, and damned if the trees don't grow and get harvested - change is ever persistant. So, a nice trail through the forest one sees in the online imagery now bisects a farm that has a six foot granite fence around it. Also, it is interesting how cow paths look remarkably like viable trails in an image genereated from high above the earth.
Now, anyone who knows Larrie knows that simple is not common in his vocabulary. Alli refers him as the great complexifier. Case in point: Google Earth exchanges its data in a file format known as .kml, which is an attribute rich xml file. However, Google Earth is the only user of that format, and GPS uses a standard format known as .gpx. A conversion utility was required to translate one file format to another. Simple; no problemo. The solution required the creation of a file conversion utility thereby enabling upload of said .kml data into the GPS (online utilities were found to be lacking or not workable / usable). The converstion utility took a bit of coding, but perserverance was repaid with an GPS acceptable .gpx file.
Normally, the group navigator uses MapMyRide.com create new tracks, which are then uploaded into a GPS for ride navigation. At the conclusion of a ride, the navigator uses MapMyRide to import actual GPS ride data, which can then be exported to Google Earth. Heres the thing - MapMyRide uses Google imagery, but it does not allow as fine grained zoom as does Google Earth. Hence, the reason Larrie choose Google Earth, and the reason the data required conversion. Said conversion tool was created, track converted, and loaded into GPS for testing and use. Simple, in a complex way.
The loaded track was tested. The first 6km, and the last 10km were tested by on the ground navigation, and success was achieved resulting in a wary and false bravado on the part of the fledgling navigator. The track was fine tuned with new points, and the final version was converted and loaded into the GPS for the Sunday ride, which was predicted as around 42-43 km. in length.
In the ride post mortem, group leader Arun Katiyar generously stated that it was a "brave" track, but the truth be known that comparing the predicted to actual ride data indicated that we were off the track more than we were on the track. If it had not
been for others in the group with on the ground knowledge of roads and destinations, and pretty good navigators, we would still be out in the outback slogging through thorny brush in search of the proper path, rather than the freshly marked cow path that we were following - on foot no less as we could not ride through the bramble. Our arms shredded by the thorns, bleeding, spirits deflated, we finally emerged at the forest exit underpass. Somewhere in this scenario, Arun chose to tell the group of the thrill of biking through Jeruselem. Quite possibly the thought of thorns, bleeding brought out the image of resurrection at the underpass. Just a thought.
While searching for the path out of the thorny brush, someone commented that we had discovered the "Bermuda Triangle" of the area, and when looking at the actual ride map, the lines traced by this particular "lost" episode did loosely resemble a devilish figure; so, who knows... In total, we did 46km over 6 hours burning up 1,772 calories, and everyone was ever so glad to get home and get off their bikes even though member of the group served up some great trail food in the form of angioplasty ready ghee based sweets amoungst biscuits and bars.
NTSB, who reviews all transportation related safety errors, is still reviewing the recordings from the trip black box. An error was discovered in the Google Earth track data, which created a "loop" in the track, but that in and of itself did not create the chaos. Artifacts such as the GPS accuracy, which is +- 19m, and the level of zoom in have been considered. Also, the particular view of the navigator using the GPS (follow the road map) vs. other views (such as a compass)offered by the device are all under review. It should be noted that there are no topographical maps for India; so getting detailed GPS data as we enjoy in the USA is just not possible. And, finally, as pointed out by Alli, perhaps Larrie needs bifocal sunglasses to read the small GPS screen - just perhaps.
Theories avail and testing remains, but root causes are elusive. Needless to say, it is doubtful the group will ask Larrie to create a new ride and lead them anywhere, anytime soon. Maybe they should just hire a cow, they seem to know where they're going - their trails are everywhere, and the trails are pretty well marked. I wonder if Google ever considered putting GPS transponders on the cows....
Larrie spent the week of June 7-14 creating a new track and vetting it both on the ground and with others in the group. The goal was to get to a eucalyptus forest that is East of the train tracks and the object of the January 18 ride. Using Google Earth, a gross track was laid out, and then the details were filled in. A total of 348 points were plotted using Google Earth, which should have provided sufficient details to assure a leisurely ride; however, a cautionary note about online imagery - it's old, and we humans continue to shape our environment constantly, and damned if the trees don't grow and get harvested - change is ever persistant. So, a nice trail through the forest one sees in the online imagery now bisects a farm that has a six foot granite fence around it. Also, it is interesting how cow paths look remarkably like viable trails in an image genereated from high above the earth.
Now, anyone who knows Larrie knows that simple is not common in his vocabulary. Alli refers him as the great complexifier. Case in point: Google Earth exchanges its data in a file format known as .kml, which is an attribute rich xml file. However, Google Earth is the only user of that format, and GPS uses a standard format known as .gpx. A conversion utility was required to translate one file format to another. Simple; no problemo. The solution required the creation of a file conversion utility thereby enabling upload of said .kml data into the GPS (online utilities were found to be lacking or not workable / usable). The converstion utility took a bit of coding, but perserverance was repaid with an GPS acceptable .gpx file.
Normally, the group navigator uses MapMyRide.com create new tracks, which are then uploaded into a GPS for ride navigation. At the conclusion of a ride, the navigator uses MapMyRide to import actual GPS ride data, which can then be exported to Google Earth. Heres the thing - MapMyRide uses Google imagery, but it does not allow as fine grained zoom as does Google Earth. Hence, the reason Larrie choose Google Earth, and the reason the data required conversion. Said conversion tool was created, track converted, and loaded into GPS for testing and use. Simple, in a complex way.
The loaded track was tested. The first 6km, and the last 10km were tested by on the ground navigation, and success was achieved resulting in a wary and false bravado on the part of the fledgling navigator. The track was fine tuned with new points, and the final version was converted and loaded into the GPS for the Sunday ride, which was predicted as around 42-43 km. in length.
In the ride post mortem, group leader Arun Katiyar generously stated that it was a "brave" track, but the truth be known that comparing the predicted to actual ride data indicated that we were off the track more than we were on the track. If it had not
been for others in the group with on the ground knowledge of roads and destinations, and pretty good navigators, we would still be out in the outback slogging through thorny brush in search of the proper path, rather than the freshly marked cow path that we were following - on foot no less as we could not ride through the bramble. Our arms shredded by the thorns, bleeding, spirits deflated, we finally emerged at the forest exit underpass. Somewhere in this scenario, Arun chose to tell the group of the thrill of biking through Jeruselem. Quite possibly the thought of thorns, bleeding brought out the image of resurrection at the underpass. Just a thought.While searching for the path out of the thorny brush, someone commented that we had discovered the "Bermuda Triangle" of the area, and when looking at the actual ride map, the lines traced by this particular "lost" episode did loosely resemble a devilish figure; so, who knows... In total, we did 46km over 6 hours burning up 1,772 calories, and everyone was ever so glad to get home and get off their bikes even though member of the group served up some great trail food in the form of angioplasty ready ghee based sweets amoungst biscuits and bars. NTSB, who reviews all transportation related safety errors, is still reviewing the recordings from the trip black box. An error was discovered in the Google Earth track data, which created a "loop" in the track, but that in and of itself did not create the chaos. Artifacts such as the GPS accuracy, which is +- 19m, and the level of zoom in have been considered. Also, the particular view of the navigator using the GPS (follow the road map) vs. other views (such as a compass)offered by the device are all under review. It should be noted that there are no topographical maps for India; so getting detailed GPS data as we enjoy in the USA is just not possible. And, finally, as pointed out by Alli, perhaps Larrie needs bifocal sunglasses to read the small GPS screen - just perhaps.
But the reality is that while Larrie's navigational skills are at the
apprentice level, Google Earth's ability to map a set of data to it's imagery is off a bit. As is noted in the picture at right, the lines of the proposed to the actual do not match, nor are they close to the imagery provided. (Note: The proposed line is the one with the grey numbers on it.) When the track was plotted, the points mapped to the imagery, but the resulting GPS coordinates were off a bit. So, it could be that Google Earth has a rounding issue - hmmm, wondering if the Google cloud utilizes the old Pentiums that had the division error.
Theories avail and testing remains, but root causes are elusive. Needless to say, it is doubtful the group will ask Larrie to create a new ride and lead them anywhere, anytime soon. Maybe they should just hire a cow, they seem to know where they're going - their trails are everywhere, and the trails are pretty well marked. I wonder if Google ever considered putting GPS transponders on the cows....
2 comments:
Larrie,
The group did ask you to lead the ride tomorrow. So there! You are good.
Your account of the ride is hilarious and made for a great read -- you should also take over writing the ride reports.
The funny truth is that most roads in India were laid out along the paths that cows created while grazing. That's why none of them are straight :)
All the best for the ride tomorrow. Pity I can't join, but I am waiting for the report and the pictures.
Larrie,
Great ride report. Though Arvind had warned me (first timer to this cycling group)enough about this Looonnnngggg 42Km plan, but streching it by extra 4.67832Kms was almost near death experience for me. I wont forget your "response" when @37Km mark I asked you how much more to go :-)
Having survived, I must say it was great first experience.
cheers
Raj
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