Vehicle Trackers

[JoeBiff]

How much reliance can be placed upon these devices?

How "refined" is their HDOP?

At one-minute data collection intervals, it leaves a large gap between which to extrapolate how a vehicle is driven? (Unlike the shorter time intervals which Garmin use, i.e. 10-15 seconds)

Anyone any thoughts?

JB

 

[Muppet]

We use Tom Tom trackers and Satnav systems on our vans at work. They have 10 second data collection intervals but the online web displays are only updated at 1 minute intervals, presumably for bandwidth reasons?

In reality, the evidence the provide (if that's what you mean by HDOP) can and has been used by the police - we had a vehicle stolen and I was able to provide proven evidence of the route the van had taken, where and how long it had stopped for at various points on it's journey and the exact route it had taken. This was used to assist in a successful prosecution of the thief and his incarceration.

hth

 

[Neil W]

We've tracked vehicles at work and the info we get is speed, location direction of travel etc , could pin down the vehicle that was mobile down to about 200 metres.
V good bearing in mind info was going from tracker supplier to a control room and then out via the radio network

 

[JoeBiff]

Thank you for your replies.

The HDOP is referenced to the number and geo-positioning of the satellites in the sky (providing position fixing data) at any one time. In other words, if the available satellites are 'clustered' together then positional accuracy will be degraded in comparison to a series of widely-spaced satellites. Wider spacing of satellites gives a much improved position fix but fix accuracy will still not be as good as differential positioning.

Also, with the data collection, is the information not transmitted (but presumably taken from the vehicle canbus) stored on the behicle for later recovery, or does this just apply to the more complex systems?

JB