I think 10 miles per delivery is typical when you take in garden paths etc.
I think 10 miles would be excessive.This is from earlier in the thread. (Rennie)
This is important because I have tested my delivery using a more reliable GPS method.
GPS is only accurate to around 15 meters though so it won't accurately measure (or even register) the (eg) 5 meters round a hedge and 10 meters up a driveway that make up a sizable percentage of the total distance involved in walks. You probably need to add on those numbers onto the point-to-point readings you're getting from your GPS device.
For example, what reading would it give for something like this typical, symmetrical example where there would be an impassable fence or hedge separating the two properties.....
H H 2m
| <- 1m | /
---- ----
| | <- 5m
| |
-----------------
X ^ Y
10m
Whereas the point-to-point distance from X to Y is 10 meters, the actual distance traveled (including delivering mail to the two homes) is 42 meters. Whilst all of the smaller sections of this example journey are outwith the tolerances of GPS, they make up over 80% of the distance traveled. Even scaling this up to include a street with a repeating pattern so that the point-to-point would register with a +/- 15m accuracy, this would result in over 60% of the distance still being the smaller, potentially unregistered legs of the journey.
This analogy is borne out on many of my delivery points and also if the job is done with the customers privacy in mind, walking around lawns, instead of across them, and not passing across first floor windows to get to the next address, will add some considerable distance to the total distance travelled.
There could be a case about the accuracy of GPS but in my case I was able to survey my entire walk and the system was spot on. It identified the entire route correctly (exactly as i walked it that day, doing my job properly!) and I was able to upload the info and zoom in close to every delivery point to check the route thoroughly! Every point on the course can be identified in terms of speed/stationary time/speeding up/down etc. The great thing was the fact that I was able to successfully challenge pegasus because my system was deemed more accurate due to the fact it mirrored the real facts on the ground. Imagine having these indisputable facts to hand when negotiating pegasus and delivery routes. The new GPS are now extremely accurate, even if there are trees and tall buildings to obscure the readings. For our office any future revision that includes Pegagsus (all of them from now on!) will be checked against my GPS system to verify the figures. If the figures don't match we will have plenty of convincing data as to the reasons why they don't match!
I would like to add that the inaccuracy probably comes from faster moving objects like cars and not your slow coach postie who only travels at astonishing speeds approaching 4mph!!
Rennie wrote:I would like to add that the inaccuracy probably comes from faster moving objects like cars and not your slow coach postie who only travels at astonishing speeds approaching 4mph!!
GPS inaccuracies are not affected by the speed of the object but by a number of factors, including satellite positions, noise in the radio signal, atmospheric conditions, and natural barriers.
The most accurate GPS systems,like the Wide Area Augmentation System,which is used to land planes is only accurate to around 2 meters.
One particular street I deliver to with older 1950's detached houses .
ie big gardens.
25 meters from gate to gate,
25 meters to door,
25 meters back to gate.
clear to see that in this example one km of road is 3 km of walking.
In fairness I also deliver to houses with 5 meter gardens and
some town houses where the door opens on to the pavement.
importantly pegasus only seems to give you proper credit for the road portion of your delivery.
Rennie wrote:There could be a case about the accuracy of GPS but in my case I was able to survey my entire walk and the system was spot on. It identified the entire route correctly (exactly as i walked it that day, doing my job properly!) and I was able to upload the info and zoom in close to every delivery point to check the route thoroughly!
Apologies for labouring the point, but what I am saying is that although you have a visual approximation of your route, the distances for all the individual legs on the journey are all wrong to greater or lesser extents (since GPS is inherently only accurate to within +/- 15m (in any direction)). The greater the number of short legs on the journey the greater the inaccuracy will be. ie, if you are walking backwards and forwards 2m, 5m or 10m at a time and the GPS is taking readings like these actual GPS readings (green circle is a 15m radius from known position)...
... you're not going to get an accurate total specifically because the total distance of the route largely comprises these small sections (the 80% or 60% example outlined in my previous post) that lie within the tolerance.
differing opinions which is fine but the evidence is crystal clear! On other occasions I have done small (1-2 m wide) circles and zig-zags to check on accuracy and these have been clearly identified. The fact is It mimicked my precise delivery route as I checked it later the same day. There were no instances whereby distance or route deviated from what I actually performed earlier in the day! Had there been any anomalies I would have dismissed the method as being inaccurate! If reps are happy to rely on pegasus then thats fine but I can assure everybody reading this thread I would rather verify pegasus using this GPS method! This is why we have reasonable deliveries in our office that are still achievable! I cannot understand why anybody wouldn't want another set of data that has been independently gathered by the delivery postie? To be used as a tool to either contradict or verify pegasus!!
Rennie wrote:differing opinions which is fine but the evidence is crystal clear!
I would be very happy for my theorising to be proved wrong!
The only way though to check the small scale accuracy of your GPS is to do short journeys of known lengths and compare the distance actually traveled to the distance the GPS gives. If I were you I would want to clear my gadgets good name by getting three objects to form an L shape with sides of exactly 5 meters and walk the length of it and back a few times to check (as good a "real world" test as any, barring going into peoples gardens with surveying tapes). That's just me though.
Well in truth I think your GPS Data and theorising between the two of you will make a whole world of difference to deliveries or more likely not. The deliveries will be as the deliveries are intended to be according to the new guidelines and tools provided - or as Jim Royle would say GPS My Arse.
or more likely not. The deliveries will be as the deliveries are intended to be according to the new guidelines and tools provided - or as Jim Royle would say GPS My Arse.