XCSoar/Kobo

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There is a Facebook group page for those interested.

In the "attached files" at the bottom of this page you will find a "using XCSoar on kobo," which  is for pilots new to XCSoar. It is explained in the context of it running on a Kobo mini eReader, and intended for those pilots who already have existing instrumentation and wish to use their new Kobo with XCSoar primarily as a moving-map with airspace overlay.

This document assumes that the once-only (and slightly technical) set-up steps have already been done; i.e. you have a Kobo/GPS in your hands with XCSoar loaded but haven’t a clue how to use it; in short:

  • Your Kobo and GPS has been wired up
  • XCSoar first-time installation has been done
  • The one-off installation of data files (e.g. maps, airspace, etc) have all been done for you.
pa6h wiring.jpg
 

If Miles Hockcliffe set up your unit, then you will already have an XCSoar configuration (or ’profile’) that exactly matches this manual. If not, section 5 describes how you can acquire this same profile; the profile file default.prf is also attached below (click 'files').

XCSoar has a plethora of functionality, and should you wish to explore it the full 200 page manual is available at www.xcsoar.org manual version 6.7

To use your Kobo to navigate a competition task there are a few problems!

Waypoint Names
Most competitions use the short waypoint id on the task board but xc soar lists them by description, so you will have to use a crib sheet, or ask for the extra info at the briefing. alternatively you can modify the waypoint file using this spreadsheet and notepad, and load the modified file. I recommend keeping the original and the new file in your XC soar just in case.
a spreadsheet conversion can be found in the attached files.

Next problem is how to enter a waypoint that some bright spark task setter made up on the hill, as happens nearly every task

Coordonate Format Problems
It seems everyone in comps standardised the lat/long format on DDD MM.mmm but even when the units are set to make lat and long that format, when you come to enter the waypoint you have to do it in degrees minutes and seconds!
This is a reported bug and has been assigned the lowest priority for enhancement by the XC soar group.
use this spreadsheet to convert minutes and seconds to minutes and decimal minutes. Put this on your smartphone so you can use it at the briefing if necessary.

Actually entering the new waypoint
Seems XC soar don't think there is anything wrong, they classed it as "worksforme"! Enter the new turnpoint and where has it gone? its in the list, then its gone?! Well there is a little trick to making it actually save - you must re-select the waypoint file even though its already selected. Here's a full description of how to do it.

Competition start
XC soar will only do one start time, so you must time any extra start increments by other means. You should set the start open time (task rules) to the first start time - then the arrow wont progress to the next turnpoint until the start has opened. Set the start close time to the task end/goal close time because otherwise it wont progress to the next trunpoint if you start late. There is also a start max height (which I suggest is set to maximum 10,000ft) and maximum speed (set to 200km/hr!) to prevent them ever restricting your start. These values can be set in the default task rules.
It will also only do exit starts. So in the case of an entry start you must use the first turnpoint as a start and time it by other means.

Stick on gesture crib sheet
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There is  a stick on menu available in the attached files 

 

further reading, from Skywings.

Kobo/XCSoar – lessons learned

Following on from last months Kobo/GPS/XCSoar article, here's a few lessons learned which is especially relevant for those embarking on a self-build unit.

By far the most common issue encountered is what people refer to as 'bricking a Kobo'. The phrase 'brick' is unfairly harsh, as all that has happened is the software or data on the Micro SD card (see photo) has become corrupted. The software/data is easily recovered, just like any computer system and its recovery is covered further below. The corruption typically happens during the initial load of the XCSoar software/data, either because the software or data is copied to an incorrect directory, or the 'write' of the data to the Kobo's Micro SD card fails (the UK map file is particularly large at 18 Megabytes). From the Kobo/XCSoar forums worldwide it is evident this happens occasionally, and from visibility of around 100~150 Kobo/XCSoar builds in the south west UK, I know of around 6 cases where this has happened.

The second most prevalent issue is seems to be damaging the GPS chip. Physical damage to the contacts that the wires are soldered to is the common issue. I have heard of 2 cases out of approx 100~150 builds where this has occurred.

There have been a few cases of physical damage to completed units; unsurprisingly, treading on the unit doesn't do it any good (!), neither does squashing it in a tight/packed harness. The original Kobo cardboard box makes an excellent safe storage box with its 1cm square honeycomb 'buffer' around the edge.

It seems that debris (e.g. a stray bit of grass) on the screen can confuse the unit; the kobo seems to think you have started (but not finished) a 'screen stroke' to instruct it to do something – blowing across the screen quickly clears the problem. For this reason, I believe avoiding debris during construction is also a good idea, so that debris cannot interfere with the screen infrared sensors. For example, cutting or melting a hole in the unit for the GPS wires may be preferable to drilling.

A minority of users have flattened their battery and subsequently been unable to get their Kobo to turn on. Conversely, many users with flat batteries have had no such problem. It is speculated that this may be a historical issue that has been overcome by Kobo, subtly implemented by the ‘Kobo update’ when you first connect your Kobo to the internet which automatically brings the Kobo software up to date via Kobo.com. The speculation is if you miss this step (and instead start with the load of XCSoar), you risk retaining the ‘old’ Kobo software (your unit may have been on the shelf for a year or more) and hence avoid resolving any Kobo issues that Kobo has otherwise overcome.

There seems to be some folklore that eReader screens struggle in cold conditions. As Colin mentioned in his Nook review last month (the Nook uses the same screen) there don't seem to be any reported problems from the flying community. After extensive forum trawling I haven’t discovered any problems from the Kobo book-reading community either. I have now flown 35 XC hours, with half of them in uncomfortably cold conditions and have had no issues. The only reference I could find to achieving a sluggish screen was a test done in the harsh Canadian winter, where a guy walked in different directions and it was only by exposing the screen to a fiercely cold wind that he managed to make the screen sluggish (eReader screens are oil based).

Recovering a Kobo Micro SD card.

This process is necessary if during the initial load of XCSoar (both software and data) something goes wrong which renders your Kobo inoperable. The same issue could probably be achieved by a one-off update of a data file but I think this is less likely.

Inside the Kobo there is a 4Gb Micro SD card (see picture). Most Kobo/XCSoar related forums recommend backing up the card before installing XCSoar in case anything goes wrong. However, the backup isn’t a straightforward windows 'copy & save', as the Micro SD card contains 2 partitions: one for Linux (the operating system) and a 2nd one that is windows-based so that files can easily be updated from commonly-used windows based computers. This means that a simple ‘copy’ from either a Linux or windows based utility will not suffice. For example, if you were to view the contents of the Micro SD card using Windows Explorer you won’t see the Linux partition. For this reason you need a utility that takes a ‘digital image’, which is a byte-by-byte copy of the entire Micro SD card, a process that has no interest in the type/nature of underlying files – it will simply copy every byte of the whole 4Gb even if, say, only 10% of the disk has actually been used.

To perform a recovery you will have first had to have taken a backup (as we always do, don’t we?) and to do this you will need:
• A Micro SD card reader/writer (available over the internet for around £6)
• A utility that will perform a digital copy (e.g. the freeware ‘Win32DiskManager’ works well)

Once you have taken a backup, you always have surety you can put things right and start again if you experience a problems. If you are already unfortunate to have ‘bricked’ your Kobo and didn’t take a digital image, then contact email and your card can be restored (free) by return of post. Better still, it can restored with an image from a micro SD card that already contained a ‘completed’ XCSoar installation; hence after reinsertion of the recovered micro SD card XCSoar is ready to use on the Kobo.

Mounting your PA6H GPS

A variety of methods have been used to successfully mount the PA6H GPS on the edge of the Kobo. Most people tend start by to sealing the underside of the GPS - where the electrical contacts are - with epoxy resin prior to epoxying it to the unit itself. The shiny surface of the kobo is best scored beforehand for good adhesion. The unit can then be sealed/finished with any of: a moulded surround with Millipuit (epoxy putty), Sugru (a more plastic putty), moulded covers (ranging from the lightweight moulding the PA6H is delivered in, to a sturdy plastic top from Tescos 'Almond cream' shampoo - I kid you not), or a simple 64mm x 6mm plastic 'shroud' around the edges which can then be fixed/sealed with epoxy resin and painted with enamel (see photo). Covering the antennae on the top of the PA6H with plastic or enamel paint doesn’t present a problem. Covering with the various putties mentioned above seems to work fine for most users, although from forum-trawling I came across one side-by-side test where a putty-covered unit was repeatedly locking on to 2~3 less satellites than an identical unit without putty.

Map files & Airspace files

The software/data in dropbox location referenced by the self build instructions in the pdf below or units supplied by Miles Hocklcliffe or Neville Almond email will have a UK map file and 2014 UK airspace with relevant/mandatory airspace and advisory airspace that we treat as a no-go (for comp/xc purposes), e.g. drop zones. Airspace files for other countries can be found at http://soaringweb.org, and map files for other areas/countries can be generated using the XCSoar 'map generator' at http://www.xcsoar.org/download/ by simply drawing the area you want the map for, pressing 'download' and adding the file that is generated to your kobo.

At the time of writing, made-up and ready-to-use units are still available for just £84 plus £4.50 P&P - email for more detail or to buy one.