Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > comp.sys.raspberry-pi > #9801

Re: Tracker

Show all headers | View raw

In message <mvgqaf$lmb$2@dont-email.me>
          Martin Gregorie <martin@address-in-sig.invalid> wrote:

> On Mon, 12 Oct 2015 13:50:47 +0100, Alan Adams wrote:

>> I'm looking at this for locating Duke of Edinburgh's award expedition
>> groups. They need to carry it, hence the weight limit, and the Gold
>> expedition runs for 4 days, hence the battery life limit. (It would be
>> possible to exchange batteries each night if that proves essential.) The
>> rate of travel is around 3 to 4 km per hour, so a position every 30
>> minutes is adequate. We would be in areas of very poor mobile phone
>> signal, so a text message has a chance of getting through while a voice
>> call fails. There isn't enough coverage for data, so anything requiring
>> an Internet connection won't work.
>>
> Have you looked at any of the satellite-linked tracking systems? I know
> nothing about what is made and/or sold in the UK, but the Americans seem
> to like the SPOT2 and and the Delorme inReach systems. Both have a 'Red
> Button' help capability and the inReach offers 2-way text messaging, and
> those flying gliders in the US west tend to carry them because they can
> get a text message or position out when a satellite is in view.

> This link gives the inReach's capabilities, battery life, weight etc. as
> well as UK sources for it.

> http://www.inreachdelorme.com/product-info/inreach-explorer.php

> Both inReach and SPOT3 is available via Amazon UK - Spot 3 is around half
> the price of the inReach and a bit less capable (no free form TXT message
> transmission, I don't think it holds an internal copy of your track).

> Both are fairly rugged and weight somewhere in the 100 -150g range, so
> comfortable under your 500g limit, even with a few sets of spare
> batteries.


>> The whole thing needs to be fairly rugged, and moderately waterproof. It
>> can be in a sealed plastic bag, and doesn't need to be accessed during
>> the expedition.
>> 
> I think the above devices both fit these requirements.

> There may well be other similar devices, but I haven't seen them
> discussed on rec.aviation.soaring, which is where I heard about these.

>> Extra features which shouldn't add much to the complexity or power use
>> could be a panic button, which sends an immediate update together with
>> the word "emergency" for instance, and the ability to send to a list of
>> maybe 3 phones.
>>
> When you buy one of these, you set up login on their website, pay for a
> satellite subscription (typically 12months) and register one (or more?)
> phones. I gather that they ring the phone(s) in an emergency, i.e. if the
> red button is pressed. You can use the website login to see where the
> device is on a map, follow progress, etc.

The snag with that is that the person doing the tracking may well be 
in a poor signal area and unable to access the internet. Typical areas 
would be the New Forest, where there's only a data connection in the 
immediate vicinity of Lyndhurst and Brockenhurst, and Dartmoor where 
away from Princetown you are isolated. The Lake District too is very 
sparsely covered.


-- 
Alan Adams, from Northamptonshire
alan@adamshome.org.uk
http://www.nckc.org.uk/

Back to comp.sys.raspberry-pi | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

Tracker Alan Adams <alan@adamshome.org.uk> - 2015-10-12 10:20 +0100
  Re: Tracker Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2015-10-12 08:12 -0400
    Re: Tracker Martin Gregorie <martin@address-in-sig.invalid> - 2015-10-12 16:38 +0000
  Re: Tracker Martin Gregorie <martin@address-in-sig.invalid> - 2015-10-12 12:18 +0000
    Re: Tracker Alan Adams <alan@adamshome.org.uk> - 2015-10-12 13:50 +0100
      Re: Tracker ray carter <ray@zianet.com> - 2015-10-12 14:10 +0000
      Re: Tracker Martin Gregorie <martin@address-in-sig.invalid> - 2015-10-12 17:23 +0000
        Re: Tracker Alan Adams <alan@adamshome.org.uk> - 2015-10-12 18:41 +0100
          Re: Tracker Martin Gregorie <martin@address-in-sig.invalid> - 2015-10-12 19:15 +0000
            Re: Tracker Alan Adams <alan@adamshome.org.uk> - 2015-10-12 21:02 +0100
            Re: Tracker mm0fmf <none@mailinator.com> - 2015-10-12 21:46 +0100
      Re: Tracker Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2015-10-12 20:12 -0400
        Re: Tracker dave <dave@cyw.uklinux.net> - 2015-10-13 09:59 +0100
          Re: Tracker mm0fmf <none@mailinator.com> - 2015-10-13 19:26 +0100
  Re: Tracker The Natural Philosopher <tnp@invalid.invalid> - 2015-10-12 19:24 +0100
  Re: Tracker franssoa <franssoa@email.invalid> - 2015-10-13 14:55 +0200

csiph-web