Yet Another Cycling Forum

General Category => Audax => Topic started by: Fidgetbuzz on October 03, 2010, 10:25:02 am

Title: DIYs / Track logs / Shortest distances
Post by: Fidgetbuzz on October 03, 2010, 10:25:02 am
Bear with me for a moment while I sketch a snag that I have just hit.

I ride a 300+ back from family in Petersfield to Norwich several times a year. I use 6 controls - Weston ( Petersfield) Marlow, Berkhamsted, Hitchin, Cherry Hinton ( Cambridge) Brandon Home. Depending on traffic conditions / time of day I do have 2 or 3 minor route variations - and they make the route 325 +/- 5kms

Several years ago Sheila and I agreed using mapsource delivery van direct that this was over 300. In fact most often the ride is about 322kms.

When i switched to Danial we probably never checked the route as it had been previously OKd.

I am now switching to Rich who uses Autoroute - so to make his life easier I thought that I would get a copy of Autoroute - and thx to the forum ( many thx Tatanab)I now have an old copy.

BUT - and here is the snag autoroute shows my 6 controls shortest route as 278 kms - so if I get Rich to check this he may well say No - Rog - not far enough.

Clearly i can get round this by putting in more controls ie Four Marks, Arborfield , Henley etc - but then I am going to have to visit these controls and this seems to me to be making my route a SPECIFIC route rather than an audax ride where I do not have to follow an exact route.

Clearly the definition of shortest distance was critical when you could not prove how far you had gone - ie Norwich Cambridge ( say 84kms ) -  I could ride down the A11 - I would be mad to do so - but I could. So in the old system I had to put controls away from the A11 to prove that I actually rode 107kms to get there.

But this doesnt seem to make sense to me on my Petersfield Norwich ride - provided I visited my 6 controls - and I submitted a track log that showed I had done 322 kms - why am I ( and Rich ) going to be concerned that a shortest possible route ( which I will never ride)  could be 278kms.

I think there needs to be an entry form for insurance purposes - a defined series of control points at sensible distances apart - and then it is entirely up to the rider to prove using the track log that
A) the controls were passed thru
and
B) that the distance ridden was over the 200 / 300 etc

I see no need for the checking of shortest possible distance.

Anyone else hit this snag?
Title: Re: DIYs / Track logs / Shortest distances
Post by: Martin on October 03, 2010, 10:41:54 am
Roger; yes AR often way underestimates distance, this may be because it wants to take you on roads that aren't actually roads or across ferries etc; have you examined the AR route?

If you add Four Marks etc as additional controls this makes it no less an Audax ride, you would still be required to visit these extra places by whichever route you wished, just that in practice the shortest route would be the route you are going to take anyway.

I've tried putting your control points into viamichelin which is equally admissable for AUK purposes 146km to Hitchin;

Google maps 153 thence to Norwich, yes it's mostly A11 etc lunacy as you say; but you are allowed to ride along those roads so to make sure it's longer not using those roads which you plan; extra controls would seem the way forward
Title: Re: DIYs / Track logs / Shortest distances
Post by: Fidgetbuzz on October 03, 2010, 10:57:21 am
I have played with Autoroute a bit more - the majority of the difference seems to come in the Petersfield to Marlow leg - shortest if I just use these 2 points is about 80kms - if I add say 3 more controls which would be on my "standard"  route then i go up to 96kms - but even this would only get 278 up to 294.

So still the key question

Why does shortest route matter one iota - when I can demonstrate from the track log - that I did NOT ride the shortest route
Title: Re: DIYs / Track logs / Shortest distances
Post by: Martin on October 03, 2010, 11:03:50 am

Why does shortest route matter one iota - when I can demonstrate from the track log - that I did NOT ride the shortest route

yes it does; because as you have alluded to we are not validating a prescribed route per se; but the shortest distance between pre-nominated locations. In order to make the shortest route match more closely your gpx distance you need to add those extra locations; once you've done that there is nothing else to do; the tracklog will confirm you have passed through them  :)
Title: Re: DIYs / Track logs / Shortest distances
Post by: Martin on October 03, 2010, 11:10:59 am
I've entered your initial controls into my AR 2010 and get 350km; but if I select shortest route for all segments it comes down to 290
Title: Re: DIYs / Track logs / Shortest distances
Post by: Fidgetbuzz on October 03, 2010, 11:23:13 am
I've continued playing to get the route to Chery Hinton to come "right" I have to have
14 "control" points - compared with my old 3.

The need to prove shortest route distance is an irrelevancy - left over from the days when I MIGHT have ridden the shortest route - now the track log proves that I did not.

14 controls instead of my 3 just makes no sense to me - it prescribes my route very tightly - when there is no need for this at all
Title: Re: DIYs / Track logs / Shortest distances
Post by: Martin on October 03, 2010, 11:27:19 am
I've got it up to 302 by just adding Four Marks and Henley-on-Thames making 9 controls.

I don't think anythings changed in the rules; AR (and viamichelin by bike which I'm assured comes out more or less identical) was always the means routes were validated AFAIK whether by receipts or gpx.

Once again; AUK operates by validating distances between control points whether they be on calendar; permanent or DIY events; the route taken between them is discretionary and can therefore not be used to validate the ride. I cannot answer for why this ride was previously allowed using just 4 controls but if it was presented to me as such I would be obliged to turn it down as a 300km ride without extra controls.
Title: Re: DIYs / Track logs / Shortest distances
Post by: Chris S on October 03, 2010, 11:45:34 am
Just done ViaMichelin - it gives 296 as follows:

Start - Marlow: 80
Marlow - Berkhamsted: 30
Berkhamsted - Hitchin: 35
Hitchin - Cherry Hinton: 45
Cherry Hinton - Brandon: 49
Brandon - Fidgetville: 57

To my mind, this route is always going to be way overdistance when ridden because there are (non-motorway) trunk routes available that make the shortest routes between controls much shorter than you'll actually ride.

But the rules are clear. Your contract with the ride is shortest distance between controls, and several methods are showing that as underdistance.

As Martin says - stick an extra control in the worst offending leg (which you can just ride through if you are doing GPS Validation) to force it over 300km.

As you know - what you ride "on the day" is irrelevant; that is not the basis of the contract you have with the event.
Title: Re: DIYs / Track logs / Shortest distances
Post by: Fidgetbuzz on October 03, 2010, 03:40:46 pm
Interesting Chris - we have a different take on this.

Your concept is that I have signed up to do a ride that is at least 200kms as the shortest route between controls
My thought pattern is that I have signed up to do a ride of at least 200kms that passes through  certain controls

Clearly in the past AUK had to have a shortest route between controls to verify a 200 - as I could have ridden the shortest route  ( even if it was crazy - c.f. my Norwich Cambridge down the A11) and there was no possibility for evidential proof that I had not ridden the shortest route.

Now however the world has moved on - I can prove that I have not used the shortest route  - so why the need to stick to the old requirement of shortest distance between controls.

Obviously I can add more "controls" into my DIY rides to satisfy the shortest route argument -- but do i really need to - Petersfield to Norwich the way I ride it is about 320 , using my 6 controls- and the track log will prove this.

Is it relevant that by notionally riding a route that I haven't ridden and will never ride - I could have done it in 280kms. Does this really invalidate the ride "contract" that you refer to and that I have a  different interpretation of?

This isnt  a major problem - clearly i can accommodate the shortest requirement if needed by using more controls-- but it just seems bizarre to me that I need to prove that a route nobody would choose to ride in practice is at least the required distance.
Title: Re: DIYs / Track logs / Shortest distances
Post by: Chris S on October 03, 2010, 03:46:54 pm
Your concept is that I have signed up to do a ride that is at least 200kms as the shortest route between controls

From everything I've read here and elsewhere, this is how I believe it works. GPS validation is just a means of showing you passed through the agreed controls - but you still need to agree the controls in advance, and any extra is entirely irrelevant to the event, just as it would have been if you had been collecting receipts.
Title: Re: DIYs / Track logs / Shortest distances
Post by: Martin on October 03, 2010, 03:49:08 pm

Now however the world has moved on - I can prove that I have not used the shortest route  - so why the need to stick to the old requirement of shortest distance between controls.

because DIY rides by GPS are just another means of validating distances according to the current AUK regulations; which is that the distance must be no less than the minimum distance between controls, in keeping with AUK's principle of "allure libre" ie free route between controls,

nothing's changed except the means by which the visiting of those same control points is recorded.

(from the website)

Plan your route
Planning a route is easy:


Decide on the distance. We validate rides at 50km, 100km, 150km, 200km, then at 100km intervals up to 1000km.
Design your route. Check carefully that the shortest distances between controls add up to at least the distance you nominated. It doesn't matter what route you actually ride, so long as it isn't possible to ride less than the nominated distance.
A good place to start is to place checkpoints at all the ‘corners’ of your route. This is simple if you use Google Maps set to ‘walking’, or Microsoft Autoroute with each section set to ‘shortest distance’.

REMEMBER! You don’t actually have to ride the shortest distance between your checkpoints. You can choose any route you like, as long as you pass through the checkpoints.

It may be worth finding out what software your local organiser uses to check route distances. It’s up to you to make sure your route meets the minimum distance rule.


if you want it changed to what you are suggesting the AGM is that way ->

Title: Re: DIYs / Track logs / Shortest distances
Post by: Feline on October 03, 2010, 04:01:40 pm
The way Audax has evolved to embrace GPS technology is excellent, but isn't it important that in doing so it has to be careful not to give GPS users an advantage over those riders who don't have it?

If all the .gpx is doing is providing proof of passage through control points that a non-GPS user could do another way then all is well and good, but using it to prove a mileage between those controls would give the user an advantage.
Title: Re: DIYs / Track logs / Shortest distances
Post by: teethgrinder on October 03, 2010, 04:30:42 pm
The way Audax has evolved to embrace GPS technology is excellent, but isn't it important that in doing so it has to be careful not to give GPS users an advantage over those riders who don't have it?

If all the .gpx is doing is providing proof of passage through control points that a non-GPS user could do another way then all is well and good,

Allready, that is an advantage. No scurrying around to find a control or having to rush to get there before the shop shuts. Presumably much easier to follow than a routesheet (I've never used GPS) almost certainly easier than stopping to unfold a map every now and then.
GPS are very advantageous, isn't that the point?
Owning a computer also gives some advantages over those who don't. Planning a DIY is now a breeze. I remember the days of planning Mesh rides with a crude Mesh map, road atlas and calculator. I'd still have to do similar if it wasn't for my computer. Twas a godsend in 2007 when I was planning 1000k of routes every week for the most part of 2 months, I can tell you.


Quote
but using it to prove a mileage between those controls would give the user an advantage.

The distance between controls has allready been proven because the route is OK'd by the DIY organiser before the actual ride takes place and all routes are subjected to the same scrutiny by the DIY organiser. Whether you take the shortest route or go a longer way is down to you. GPS, I expect, would help you keep to the shortest possible route. The GPS would only be evidence that you've cycled along that particular route.
Title: Re: DIYs / Track logs / Shortest distances
Post by: Martin on October 03, 2010, 04:33:18 pm
The way Audax has evolved to embrace GPS technology is excellent, but isn't it important that in doing so it has to be careful not to give GPS users an advantage over those riders who don't have it?

If all the .gpx is doing is providing proof of passage through control points that a non-GPS user could do another way then all is well and good, but using it to prove a mileage between those controls would give the user an advantage.

exactly; obviously gps does give an advantage over paper validation as there is no need to stop and obtain proof of passage (which may well be unobtainable otherwise) but it should not enable extra km over the shortest distance between controls;

this thread is sort of linked to the infos on perms one; hopefully it will be discussed at the AGM. My opinion is that wherever possible flexibility for accepting proof of passage should be allowed to the perm and DIY organisers; again with the aim of making it fairer all round.
Title: Re: DIYs / Track logs / Shortest distances
Post by: BlackSheep on October 03, 2010, 05:04:12 pm
A very interesting topic/thread.

May I ask a two part question please, it's not specificly aimed at any individual.

Whom determines which 'Standard' is used for the route mapping, and what is/are their reason/s for this choice?
Title: Re: DIYs / Track logs / Shortest distances
Post by: Martin on October 03, 2010, 05:10:18 pm
A very interesting topic/thread.
Whom determines which 'Standard' is used for the route mapping, and what is/are their reason/s for this choice?

it is standard and has been since DIY perms were set up; Autoroute set to shortest distance (don't ask me about delivery vans or driving speeds) or viamichelin set to cycle; both give very similar results. I cannot comment on which means event secretaries use but I imagine it's AR.
Title: Re: DIYs / Track logs / Shortest distances
Post by: vorsprung on October 03, 2010, 06:25:07 pm
Fidget me dear,
Just ride the 200 miles and don't bother with a perm form
Title: Re: DIYs / Track logs / Shortest distances
Post by: mikewigley on October 03, 2010, 07:27:53 pm
I think I agree with Mr Buzz.  You've signed up to do 300km that goes through those 4 points, and it's then up to you to prove your distance is worthy of validation.  If you've got a GPS then job done.  If not, then there is no way you could demonstrate the distance is right, without adding more controls in the first place.  But it's the rider's responsibility (as I see it) to prove the validation requirements have been met.

If we're accepting GPS as a valid measuring device, then let's use it properly (and sadly that doesn't yet include me).  How you rephrase the rules might be tricky, and I understand the deadline for AGM proposals has gone, but I suspect topics such as this might get an airing at the AGM as part of the Infos discussion.
Title: Re: DIYs / Track logs / Shortest distances
Post by: MSeries on October 03, 2010, 07:35:00 pm
GPS should NOT make  the entry and approval any different.  The do permit controls to be selected which are not towns so one can make a route which is exactly 204km, when ridden and when checked using AR. Paper POP needs  a town and hence causes rides to be over distance as we need to ride to a town.

14 controls is OK, you just ride through a Grid Ref like you do hundreds more. A bit more effort in the planning and validations but it's only done once (Per ride for the validations but that's not the riders job)

Should be latitude and longitude IMO though since that is what all mapping software and GPS use. Conversion to GRid Ref depends on which algorithm once uses.
Title: Re: DIYs / Track logs / Shortest distances
Post by: Martin on October 03, 2010, 07:59:39 pm
I think I agree with Mr Buzz.  You've signed up to do 300km that goes through those 4 points, and it's then up to you to prove your distance is worthy of validation.  If you've got a GPS then job done.  If not, then there is no way you could demonstrate the distance is right, without adding more controls in the first place.  But it's the rider's responsibility (as I see it) to prove the validation requirements have been met.


unless I'm being incredibly dense; sorry but no you've also got the wrong end of the stick Mike;

DIY orgs are not given a gpx track to approve before the rider does the ride, where would they get it from? Bikely?

 we get a list of controls that we have to join the dots with to make sure the route meets the distance. Thus we have to treat a DIY gps entry the same as any other. The very tech-savvy riders I get requests from also send me an AR file with just the controls listed and hey presto it comes up with the distance; no gps required. I never get gpx routes to check before the ride.

can some other DIY orgs please confirm this? or else I'm going out and may be some time...
Title: Re: DIYs / Track logs / Shortest distances
Post by: Greenbank on October 03, 2010, 08:04:37 pm
The DIY-by-GPS method that was proposed separately (and trialled for a while)sounds like the solution to FB's problem.

He submits a proposed GPX track of his route showing that it is more than 300km. He then rides it, deciding on the day to take a slightly different route for 30km of it (due to traffic conditions) but it doesn't make much of a difference to the total distance ridden (still over 300km). A few usual proof-of-passage receipts/stamps are gathered along the way (since you'll probably be stopping for food at various places anyway) and you're all good.

This should be an addition to the current DIY schemes, not a way of using a tracklog as proof-of-passage for DIYs arranged through the current method.
Title: Re: DIYs / Track logs / Shortest distances
Post by: RichForrest on October 03, 2010, 08:17:54 pm
All the gps does is prove you've ridden the route through the controls you enter on the entry form.
The controls still have to add up to the proposed distance before you ride.
I use the 2005 version of autoroute which may vary from other versions. I've never had trouble when sending the .axe file to both Danial and Martin for any rides I've done.

Rich
Title: Re: DIYs / Track logs / Shortest distances
Post by: red marley on October 03, 2010, 08:31:18 pm
Should be latitude and longitude IMO though since that is what all mapping software and GPS use. Conversion to GRid Ref depends on which algorithm once uses.

Feel free to move my response to pedants' corner, but just a point of information: Latitude and longitude do not give you a unique and precise location on the ground. They represent a vector from the centre of an imaginary ellipsoid. You also need the ellipsoid details (usually, but by no means always WGS84) to be certain of the location. Most differences when converting to UK National Grid (which uses the Airy 1830 ellipsoid) are because of different assumptions about the ellipsoid, not an error the algorithm as such. GPS store the ellipsoid they use and will do correct conversions when reprojecting, so it makes little difference to accuracy what projection system is used.

The reality is that the errors by using an incorrect ellipsoid are no more than a few hundred metres on the ground, so have no real bearing (pun intended) on Audax distances.

As you were.
Title: Re: DIYs / Track logs / Shortest distances
Post by: MSeries on October 03, 2010, 10:15:54 pm
Should be latitude and longitude IMO though since that is what all mapping software and GPS use. Conversion to GRid Ref depends on which algorithm once uses.

Feel free to move my response to pedants' corner, but just a point of information: Latitude and longitude do not give you a unique and precise location on the ground. They represent a vector from the centre of an imaginary ellipsoid. You also need the ellipsoid details (usually, but by no means always WGS84) to be certain of the location. Most differences when converting to UK National Grid (which uses the Airy 1830 ellipsoid) are because of different assumptions about the ellipsoid, not an error the algorithm as such. GPS store the ellipsoid they use and will do correct conversions when reprojecting, so it makes little difference to accuracy what projection system is used.

The reality is that the errors by using an incorrect ellipsoid are no more than a few hundred metres on the ground, so have no real bearing (pun intended) on Audax distances.

As you were.
It would still save us the bother of using a converter if the entry page asked for lat & lon and not GRs <- that is my point.  The GPS is not used (by me) in planning a ride, map software is and these give me Lat & Lon (autoroute, Google Maps do anyway) . GEtting TRacklogs is not a viable solution.
Title: Re: DIYs / Track logs / Shortest distances
Post by: Martin on October 03, 2010, 10:20:04 pm
GR's; and lat/long are optional on the entry form; an address will do, otherwise email the organiser and expalin where the control is; we can find it by AR
Title: Re: DIYs / Track logs / Shortest distances
Post by: MSeries on October 03, 2010, 10:25:41 pm
Can we enter lat/lon ? Where ? Some places I use are just points on the planet, no address since there is nothing there but the road, it's just a top of a hill or some random place on a road to force the shortest distance calculater to use a longer twisty road rather than the straight, busy major A road. (This where DIY by GPS wins out for me, makes it easy to submit routes where the shortest distance is the one you'll ride)
Title: Re: DIYs / Track logs / Shortest distances
Post by: Fidgetbuzz on October 03, 2010, 10:29:56 pm
I think this is a matter for some discussion - but let me make quite clear - i am very happy to ride my quoted ride at 322 ish probably having to put 2 or 3 more controls in to satisfy a (new to me) measuring system-even tho it was historically approved on a different system - but the potential problem hit me - when I realised that my new controller might reject my controls as falling short of the "shortest distance " between controls rule, even tho I was never going to ride this route - and I would be using my country lane 322 ish route always. I must have ridden this route for 4 or 5 years - maybe 3 or 4 times a year.

Although there is reference to using Autoroute and Viamichelin - I suspect that this is custom and practice not an AUK rule  - and when i first had a GPS I used Mapsource -  supported by Sheila - who advised me to use delivery van direct route - this comes up at 307 using my 6 controls. AR and VM may be used by some / all now - but this was not the case in the past.

Having seen the potential snag - I was then intrigued by the fact that the shortest route between controls - which HAD to be used in the past - was seen as applying to NOW. Clearly it is while the rules remain the same - but should the rules be the same, when I can prove my distance was 322.

I dont see the absolute  need for my controller to be satisfied in advance of any ride for which I nominate my controls to satisfy him / herself that the shortest possible route that I could ride would be xxx kms. To me it is my responsibility to ensure that a) I visit the controls  and b) have ridden more than xxx kms - if I choose to ride overdistance because it is a nice day - and I fancy going to a village over there - so be it -- if I choose to ride dual carriageways between my controls -- BUT the distance is under XXXkms - then I would not submit the tracklog and even if I did it should not be validated.

Not trying to be a stirrer -- just curious about carrying an old rule that was absolutely needed in the past  into the future.

Title: Re: DIYs / Track logs / Shortest distances
Post by: MSeries on October 03, 2010, 10:31:58 pm
It's not an old rule.
It's the current rule.

It's been like that since 2006 at least when I did my first DIY. Shortest distance between controls.

"I dont see the absolute  need for my controller to be satisfied in advance of any ride for which I nominate my controls to satisfy him / herself that the shortest possible route that I could ride would be xxx kms"
^^^^^^^^^^^^
That is required, it's how it is.
Title: Re: DIYs / Track logs / Shortest distances
Post by: Fidgetbuzz on October 03, 2010, 10:33:52 pm
Ok - carrying an existing rule that was absolutely needed when a rider could not prove where they had been - into the future when they are able to do this
Title: Re: DIYs / Track logs / Shortest distances
Post by: MSeries on October 03, 2010, 10:37:58 pm
Ok - carrying an existing rule that was absolutely needed when a rider could not prove where they had been - into the future when they are able to do this

Propose a change to the system. The existing system is needed for riders who don't use GPS though and for organisers who don't do DIY by GPS.

I don't think there was a different system before, I think your other organiser probably realised that you would not ride on the A1(M) (for example)even though AR used it as the shortest and permitted you to do something different.  My current Org doesn't permit such 'understandings', consistency for all riders is a 'must' IMO.

All you have to prove once your route has been approved is that you pass through the controls in the right order and within the time limits. The first and last control prove you rode at least the minimum distance. It's simple and  it works. Your actual rotue as planned or as executed is immaterial  to the orgs.
Title: Re: DIYs / Track logs / Shortest distances
Post by: Martin on October 03, 2010, 10:43:40 pm
Can we enter lat/lon ? Where ? Some places I use are just points on the planet, no address since there is nothing there but the road, it's just a top of a hill or some random place on a road to force the shortest distance calculater to use a longer twisty road rather than the straight, busy major A road. (This where DIY by GPS wins out for me, makes it easy to submit routes where the shortest distance is the one you'll ride)

you can use whatever you like if AR can find it; if not you'll have to send a Streetmap location with a little arrow...
Title: Re: DIYs / Track logs / Shortest distances
Post by: Fidgetbuzz on October 03, 2010, 10:52:54 pm
Absolutely true that system is needed for those without GPS etc and I can not imagine 2 different rules for GPS riders and non GPS riders - so as i think about it - there can not be any rule change in the foreseeable future, and heaven help anyone trying to draft a new rule too!

However I still have the niggle - how can this ride approved for several years going through 5 or 6 controls - potentially be rejected because a different controller uses a different system ( that I did not have ) to measure a route that I will not ride. 
Why can I not inform my controller that Mapsource thru these controls comes in at xxx kms - and I will ride more than that anyway?

Anyway - enough of this I am riding a 200 tomorrow - approved by my new controller on his measuring system.
Title: Re: DIYs / Track logs / Shortest distances
Post by: RichForrest on October 03, 2010, 11:28:34 pm
Just a question, How do you do a route in mapsource?
I have that from having a Garmin gps, but as it doesn't seem to have every road in it surely it can't do the shortest route?
Title: Re: DIYs / Track logs / Shortest distances
Post by: simonp on October 04, 2010, 12:58:11 am
Just a question, How do you do a route in mapsource?
I have that from having a Garmin gps, but as it doesn't seem to have every road in it surely it can't do the shortest route?

Which map do you have?  I rarely see missing roads in the uk with the 2008 version.

If you have the basemap that came with the gps that's main roads only.
Title: Re: DIYs / Track logs / Shortest distances
Post by: BlackSheep on October 04, 2010, 07:56:25 am
Just a question, How do you do a route in mapsource?
I have that from having a Garmin gps, but as it doesn't seem to have every road in it surely it can't do the shortest route?
That's a very good point Rich.

And just as a matter of interest. How do we know that any other mapping software is also telling the truth?

I know we have to start somewhere, and I (like many) start by using MS AR, but it's a long way short of the mark when it comes to planning routes for bicycle. I always have to cross refer to some other s/w, such as that offered by Bikehike.

I don't see how AUK can validate rides for bicycle using car mapping s/w, when then the item isn't really fit for purpose.

Title: Re: DIYs / Track logs / Shortest distances
Post by: Martin on October 04, 2010, 08:35:09 am
Just a question, How do you do a route in mapsource?

much the same as Bikely; select the route tool and click around the route, it will auto-follow the road; but it has several senior moments when it sends you all round the houses, the advantage of mapsource over Bikely is that if it does this you delete the last waypoint and it deletes the route back to the last good waypoint, you can then go back and add a few more waypoints to force it on route (Bikely requires you to delete dozens of little trackpoints back individually until you are back to the last waypoint)

FB; this is why we cannot confirm shortest routes by Mapsource

Simonp; my mapsource has a few missing roads; and others that it thinks are bridleways after a while so won't send you down them even though they are a road throughout; it also thinks that some byways and RUPPs are roads.
Title: Re: DIYs / Track logs / Shortest distances
Post by: Manotea on October 04, 2010, 10:09:07 am
I don't believe any s/w based routing sytem will ever be 100% applicable to Audax purposes. How many show the 'hole in the hedge' shortcut a.k.a., the Maidenhead Manouvre on the Upper Thames/Willy Warmer, for example? Don't look, its just an example.

Now, as a Garmin user, I do all my base mapping in Mapsource. This is because apart from the fact that the S/W is on my PC it enables me to have several versions of a route in the same file, so I can play around with options. I usually end up with two routes, 'on the road' and 'controls only'.

For route validation purposes I used to load the control only route into Autoroute and submit the .axe file and a printed report as pdf which includes a summary report detailing the distance between controls, which lends the route application a certain authority. Ususally this goes through without an issue.

I do find that Mapsource and AR generally disagree on the shortest distance. It's generally not significant but can be a royal pain if AR shows mapsource underdistance by a couple of KM as I then have to go hunting for them, playing around with the controls, whatever. Its generally best all round to do this rather than raise an issue with the Org. I try and use the same version of AR as my local DIY org and as Martin has Mapsource he can view .GDB files natively. I agree that Mapsource throws in an occasional 'long cut' but these are immediately obvious from a cursory scrutiny and can be corrected by including an addition waypoint (note, not control) on the 'Controls' route,  so I really do not see that as a problem.

Historically a small amount of flexibility was offered to allow for this imprecision - well a couple of km - as DIY riders would generally clock up a few extra KM finding controls, riding to/from the start point (pre-GPS). That seems to have been lost in the search for the holy grail of the perfect solution.

To restate my opening comment I simply do not believe that any s/w routing system can ever be 100%. One does get the impression that the effort expended in searching for it is counter productive as stress testing reveals problems/inconsistencies and the route planning process more complicated, as evidenced by the endless questioning on the matter.

So what to do? I'd like to see clearer guidelines on route planning and (regardless of which tools are used) the Orgs empowered to apply some discretion. That seems to inline with the spirit of Audax.

[FWIW I'd have turned down FBs route. It's inappropriate to assume trunk roads are de-facto motorways - many scheduled routes have long distances of trunk roads albeit on overnight/sunday morning sections. Best to simply plot Controls that keep you away from them. GPS users can place controls where they chose so that isn't a problem, and the more controls one has the fewer 'extra' km one has to ride. This must be traded against flexibility for the 'on the road' route. YPYPATYC.]
Title: Re: DIYs / Track logs / Shortest distances
Post by: Greenbank on October 04, 2010, 10:19:09 am
However I still have the niggle - how can this ride approved for several years going through 5 or 6 controls - potentially be rejected because a different controller uses a different system ( that I did not have ) to measure a route that I will not ride. 

Because things are being tightened up and allowances that were made in the past are no longer being made. It's biting calendar events too, many have had to wiggle controls around to make it stand up to greater scrutiny. I'm guessing my DIY 200 up to Cambridge and back wouldn't stand up any more, despite me never riding it in less than 216km.

If anything it goes to show just how much time and effort has gone in to the calendar rides that are only a few km over distance.
Title: Re: DIYs / Track logs / Shortest distances
Post by: vorsprung on October 04, 2010, 10:46:18 am
If anything it goes to show just how much time and effort has gone in to the calendar rides that are only a few km over distance.

I used the on line ViaMichelin: Maps, route planner, route finder, UK maps, European maps, hotel booking, travel guides (http://www.viamichelin.com) to work out how appropriate my 400km route was
This is suggested as a way of doing DIY perm distances so I figured it has the "official" magic sauce

I found that some legs of the 400 were over the minimum distance but this didn't matter as others were, somehow, under the minimum distance.  On paper the "control" distance was 418km but the actual distance 413.5km

I seemed to gain the most where I was using laney shortcuts which is unfortunate as these are usually bloody awful roads. 

And of course viamichelin doesn't know about the Severn Bridge.  If I just told it to use options cycle and go to Chepstow, quite a long detour happens.




Title: Re: DIYs / Track logs / Shortest distances
Post by: frankly frankie on October 04, 2010, 10:55:57 am
Several years ago Sheila and I agreed using mapsource delivery van direct that this was over 300. In fact most often the ride is about 322kms.

When i switched to Danial we probably never checked the route as it had been previously OKd.

I am now switching to Rich who uses Autoroute - so to make his life easier I thought that I would get a copy of Autoroute - and thx to the forum ( many thx Tatanab)I now have an old copy.

Referring back to the OP I'd like to raise some points.

If the project is regularly ridden, and has already been validated - why would a new DIY Org see a need to re-invent the wheel?  Sounds to me as though Danial had the right approach here.

Regarding Mapsource in 'Delivery' mode - this almost by definition will NOT generate a shortest route - even when set to 'shortest'.  'Delivery' mode will seek to take you round the houses in towns and over longer distances will seek to take you through towns/villages rather than straight past them.

Regarding Autoroute - ISTR that originally this was used NOT set to 'shortest' - but set to 'fastest' and the speeds for each road type tweaked to make the mainest roads the slowest ones.  This gave very good results.
The problem I think is that it also gave a lot of inconsistency between different desktops - different versions of Autoroute and different individual speeds settings meant that no 2 people were seeing the same generated route.  This may be why people have gone across to using 'shortest' (if indeed they have).
Title: Re: DIYs / Track logs / Shortest distances
Post by: Greenbank on October 04, 2010, 11:06:29 am
AR's "shortest" algorithm won't always be giving you the real shortest route anyway.

The lengths it goes to to find the 'shortest' route depends on how long the leg is. The longer the leg the simpler the route it tends to prefer.

Further comments and examples in this thread: A DIY organiser's plea (http://yacf.co.uk/forum/index.php?topic=34447.msg647095#msg647095)