Benefits of GPS Vehicle Tracking

Maximum Fleet Efficiency with DPU GPS Vehicle Tracking System

Track vehicles in real time
Download movement logs
Recover stolen vehicles

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Do you ever wonder if some of your drivers are not as responsible as you hoped they were? Wouldn't you rather reward your responsible drivers, if only you could weed out the "bad apples"?

You could benefit from using a vehicle tracking system, which makes use of GPS satellite positioning technology to record a vehicle's movements during the course of each day. Vehicle tracking can include cars, vans, heavy goods vehicles, farm vehicles, and even drilling rigs.

Rental cars are sometimes not returned. This is a problem that has driven small car rental companies out of business. Installing GPS vehicle tracking systems allows them to locate their vehicles and return them to use as quickly as possible. This is just one of the applications of mobile GPS vehicle tracking. It can also record speeds, and drivers who know that their speed is being monitored tend to be more careful about driving at sensible speeds, which helps a fleet owner minimise liability and accidents as well as potentially saving lives.

Many types of vehicle fleets can benefit from GPS vehicle tracking, in applications such as trucking, distribution and goods delivery, fitting, waste collection & recycling, taxis, local authority services, highway maintenance and customer services.

A vehicle tracking system uses the GPS satellite system through a multi-channel GPS receiver to track a vehicle's movements, and transmits that information digitally over a GSM and/or GPRS phone network.

Fleet management and vehicle tracking information is then made available to the user over the internet from a server, overlaid on a map of the area.

Here are a few other things that GPS vehicle tracking can help manage:

Driving company vehicles out of authorised hours, e.g. at weekends
Detecting "side jobs" using company vehicles or even company stock
"Bad apples" have been known to reform or resign of their own volition
Overtime can be reduced
Drivers concentrate harder on finding and following optimum routes
Time of arrival at customer sites
"Padding" trips or visits with time spent on unauthorised activities
Excessively long lunches
Time spent at pubs/bars/licensed premises: Liability for "driving under the influence"?

In fact, after you have installed GPS vehicle tracking in your fleet, the mere effect of deterrence will prevent unauthorised use from happening in the first place.

Now you don't have to wait until a "little bird tells you" that someone has been taking undue advantage of your company's facilities. With a GPS vehicle tracking system, you can be like a little bird perched on your driver's shoulder all through the working day, and beyond, whenever your vehicles might be used. And you can be that little bird on every single one of your driver's shoulders, 24 hours a day, 7 days a week.

For many years, radio was used to track the movements of vehicles in police, fire, ambulance, courier, and taxi fleets, with a central dispatch office and two-way radio in each vehicle.

With GPS vehicle tracking, the driver no longer has to operate a two-way radio to converse with the dispatcher, and the driver can now concentrate on driving safely and following the best route. Many companies that never before considered using two-way radio can now find automatic GPS vehicle tracking technology to be affordable and provide an effective return on investment.

The automation of vehicle position-tracking that GPS brings means that an organisation now has access to much more frequent updates and can more effectively manage the allocation of vehicles to destinations, pickups and incidents, as well as extra information such as the length and duration of trips, fuel efficiency, and vehicle equipment status. This has to be good for the efficient running and profitability of your organisation.

Furthermore, many two-way radio systems were based on a proprietary base station which limited the service to the coverage area of the company's base station. A GPS-based vehicle tracking system used in conjunction with the public cellular telephone system is not limited to a local geographic coverage area.

Make improvements in many areas

A GPS vehicle tracking system in your fleet can prevent your vehicles being used for unauthorised purposes
A GPS vehicle tracking system in your fleet can reduce your liability from speeding, other offences, and accidents
A GPS vehicle tracking system in your fleet can rapidly locate stolen vehicles
A GPS vehicle tracking system in your fleet can alert you if the vehicle is somewhere it shouldn't be
A GPS vehicle tracking system in your fleet can monitor duration and length of trips
A GPS vehicle tracking system in your fleet can monitor inputs from other equipment in the vehicle, including alarms and refrigeration plant
A GPS vehicle tracking system in your fleet can reduce your insurance costs
A GPS vehicle tracking system in your fleet can ensure that employees follow the company procedures
A GPS vehicle tracking system in your fleet can ensure that employees are rewarded properly according to performance
A GPS vehicle tracking system in your fleet can maximise fuel efficiency
A GPS vehicle tracking system in your fleet can optimise delivery tracking
A GPS vehicle tracking system in your fleet can improve your Health & Safety record
A GPS vehicle tracking system in your fleet can minimise Shrinkage and Theft
A GPS vehicle tracking system in your fleet can help with planning to minimise empty loads
A GPS vehicle tracking system in your fleet can minimise vehicle wear & tear
A GPS vehicle tracking system in your fleet can reduce CO₂ emissions

A GPS Vehicle Tracking Data Processing Unit (DPU)

Each vehicle that you need to track or monitor will require a small Data Processing Unit (DPU) module installed. This contains an embedded computer system which provides sophisticated support for a GPS system to obtain position fixes, and a cellular radio system to communicate with your headquarters, where the base station comprises a PC, a modem and vehicle tracking front end software.

The DPU is compliant to CE and Radio & Telecommunications Terminal Equipment emissions standards, and can store the location history of the vehicle automatically over an extended period even when not in contact with the base for real-time vehicle tracking.

The DPU is something I have personally worked on, contributing both hardware and software design, since 2001.

When used in conjunction with a suitable user front end for vehicle tracking at the fleet manager's base, the DPU provides all the vehicle-based facilities to support polling, live tracking and logging of the location, speed and direction of fleet vehicles, as well as supporting an optional dedicated NAVMAN MDT-800 Mobile Data Terminal.

Other vehicle tracking options include a tractor/trailer unit with an internal backup battery, a driver keyfob ID interface, and datalogging from an external source.

The DPU automatically shuts down to a low power sleep mode when the vehicle is not in use, avoiding the problem of battery run-down that might occur with other units that don't have this sleep mode.

The DPU has the ability to send an alert text direct to a specified mobile phone if the vehicle moves out of a permitted zone, or if an external vehicle alarm connected to the unit is triggered.

The DPU is an embedded computer system in its own right, with a watchdog system to ensure reliability, and over 100 system commands for controlling the GPS, cellular radio, text messaging, software upgrades, system configuration, and logging.

At your base location, front-end software provides a map display of the vehicle tracking data, including the UK, continental Europe, the USA, the Middle East, and other parts of the world.

The software requires only a standard PC with no unduly expensive special requirements, and can communicate with every mobile DPU that is tracking a vehicle through one modem.

Background of the DPU Development Team

Key personnel started development of the current vehicle tracking DPU, which was to replace an earlier model based on different hardware, at the Central Research Laboratories (CRL) of EMI.

CRL was founded in the 1920s, and has a long record of achievement and technical innovation (Notable achievements include: The world's first public high definition television service, making the first modern stereo gramophone records, making effective the radar combating the WW2 night bomber, and the outstanding research which produced the X-ray scanner, for which the late Sir Godfrey Hounsfield received a Nobel Prize for Physiology or Medicine in 1979).

Sounds great, now what's available?

DPU sales

Accessory sales and support

Extended warranties

Field repair or return to base repair service

Customer PC service

Software upgrades

Installer training

For further information, please send an email inquiry stating your particular requirements:

About GPS

The most well-known global satellite navigation system today is the GPS ("Global Positioning System"). Its roots go back to the early 1960s, when the US Navy set up Transit, which was a satellite navigation system considerably less accurate than GPS, with nominal accuracies of the order of 100-200m. Transit navigation services ended on December 31, 1996. In the summer of 1973, the Defense Navigation Satellite System emerged as a plan to satisfy the needs of all US Services. This was merged with the Navy's Timation navigation system to become Navstar (Navigation Satellite Timing And Ranging), which became more commonly known as GPS.

In 1981, the IEEE publication "Spectrum" stated that:

"By the turn of the century, a single system - Navstar - may serve most of the United States' global navigation and position-determination needs. Although, right now, it's a military system, the Navstar Global Positioning System (GPS) has shown its worth in a variety of civilian uses: maritime, aviation, and space. If Navstar is eventually adopted for U.S. civilian use, it will provide for the first time a common system for all classes of users, and it may reverse the proliferation of special-purpose navigation and positioning systems"

Incidentally, if you see the above text including the quotation from Spectrum anywhere else, they have lifted it from my page without permission; I have quoted from a print copy of "Spectrum" in my possession that I am certain was never quoted on the web before I created this page.

Back in 1981, the lowest estimated price for an austere GPS set was about $2500, and high-performance civilian GPS sets were priced from $30000 to $45000.

Today, the functionality of what was then considered high-performance is available, with added functionality from embedded processing and mobile GSM communications, for considerably less cost.

The GPS system is described in terms of the three parts known as the Space Segment, User Segment, and Control Segment.

The Space Segment consists of a number of satellites orbiting the Earth at altitudes of 19200 nautical miles, and these satellites follow a track that repeats every 12 hours.

The Control Segment is the set of monitoring and control stations that look after the operation of the satellites and ensure that they maintain accurate timing and position information.

The User segment consists of every user that receives signals from the satellites and uses those signals for timing and/or geolocation.

Users can download the Almanac from the Space Segment; this provides orbital model data that allows the user's equipment to obtain initial estimates of which satellites may be visible in the sky. Precise data about the positions of the satellites is obtained by downloading the ephemeris data (which is updated frequently), which when combined with the almanac (which does not change very often, and hence does not need to be downloaded frequently) establishes in the user's receiver a basis for calculation of the user's position.

The user equipment also needs to measure the timing for signals received from each satellite. Given the time delay between each satellite, whose position is known, then the user equipment can calculate the user's position on the ground.

Nowadays, all the reception of GPS signals and calculation of positions is usually performed by a self-contained receiver module which is incorporated into the user equipment.

The raw GPS information is made much more useful by the addition of supplementary processing and communication capabilities. For example, the location information may be displayed together with a map from a database on a display screen. The GPS data may be retrieved remotely via a radio link, permitting remote vehicle tracking and location of property. The equipment might store records of GPS locations, allowing the periodic downloading of travel histories. The equipment might also permit the monitoring of inputs such as signals from a vehicle alarm unit, and remote control of outputs such as warning lights and immobilisers.

Advances in technology have enabled the unobtrusive installation of complex electronics such as GPS vehicle tracking receivers in a wide variety of vehicles and other mobile platforms.

For installation, the vehicle tracking receiver requires a power supply taken from the vehicle, and an antenna mounted with a clear view of the sky. For cars and trucks this can usually be accomplished without any overt indication that the vehicle tracking receiver is installed.

Almost anything that moves or can be moved can now be considered for tracking by GPS. The key factors for consideration are whether the potential loss of items (by theft, or simply losing track of where a vehicle or asset has been left in a large organisation) or inefficient use of items in terms of movements and timing can contribute significant losses compared with the situation in which complete information is available about the location and movement of items.

Basic GPS Triangulation

Let's assume you can receive signals from one satellite. The time of flight of the signal, accounting for the speed of light (radio waves) and corrections for the effect of the Earth's atmosphere, tells you the distance from the satellite, which puts you on the surface of a sphere. The snag is that you don't have a timing reference for the satellite's signal, so you need an additional satellite to set your local clock and determine the difference between the clock and the satellites. Bearing this in mind, the following argument based on knowing the distance from a number of different satellites applies, but you must add one satellite for the number required (denoted by the number in brackets) because in practice you do not have absolute time information and must obtain it indirectly by measuring multiple satellite signals.

No. of satellites:	1 (2)	2 (3)	3 (4)	4 (5)
Location information:	A sphere surrounding the satellite	The intersection of two spheres, which is a circle	Two possible intersection circles, which coincide only at 2 points	Three possible intersection circles, which coincide only at 1 point

You can see from this that in an ideal situation, 5 satellites should give an unambiguous position and time fix; 4 satellites will give a point fix that is usually pretty good because one of the points will be way off in space; 3 satellites will give an approximate location if the position has previously been established, since the intersection circle could itself intersect the Earth's surface at two possible points. In practice, there are errors inherent in the measurement process which means that the position fix is subject to an uncertainty which is reduced as the number of satellites is increased. Information about the number of satellites used in a position fix, the likely uncertainties, and the way in which the data has been calculated, is an important part of the result delivered by a GPS receiver and hence this supplementary information should also be obtainable together with the fix itself. An overall flag is usually provided that indicates whether a fix is currently acceptable or invalid.

More on Vehicle Tracking Systems

Modern vehicle tracking has its roots in the nineteenth century, when the spread of the railway in Victorian Britain became closely linked to the development of the electric telegraph, which was used for control and communication to manage the distribution of trains on track segments. In 1837, Cooke and Wheatstone developed the electric telegraph which used an electric current to move magnetic needles and thus transmit coded messages. The first operational telegraph system linked Euston station and Camden town. Telegraph machines appeared in post offices, and it became possible for a driver of a horse-drawn or early motor vehicle to send a wire reporting his arrival at a destination. At the end of the nineteenth century, several independent demonstrations of radio transmission were made, and by 1906 it was possible for the Clark Portable Army Set to be used for radio links between mobile units in the field, transported on the backs of mules. Subsequent twentieth-century developments in space satellite science, high stability electronic clocks, semiconductor microelectronics and digital computing have enabled the automatic position location and radio link technology in the form of modern GPS vehicle location systems.

Many early efforts in vehicle tracking were aimed primarily at theft-prevention for high-value loads, and tracking vehicles of expensive marques. Improvements in technology and reduced costs have allowed it to develop into a comprehensive tool for fleet management and expanded the number of ways in which the vehicle tracking technology is used, so that it is possible for such systems to pay for themselves by reducing mileage and fuel costs, which can be tracked by the system, as well as by increasing vehicle utilisation and fleet productivity.

Vehicle tracking systems for fleet management let you know where your vehicles are or where they have been, so that you can best plan and manage their future movements. Vehicle tracking techniques range from the immediate real-time live tracking that lets you know where your vehicle is at each instant, to periodic vehicle tracking or positioning updates which may be provided by updates of vehicle position every so often, usually within a number of minutes. Often a system will allow vehicle tracking updates to be made at pre-set times, on demand, or conditional on certain events occurring, such as a delivery being made. Generally the more often vehicle tracking position is updated, the costlier it is. The cheapest option is not to transmit the vehicle tracking data at all, but download it directly from the vehicle when it returns to base, providing a historical log. A vehicle tracking system company will usually also provide fleet management software applications that bring together the vehicle tracking information of the whole fleet and log travel history, calculate fuel consumption etc.

The US Government's GPS system is free to users and has been around for the longest time, so is the most popular for fleet management companies to do their vehicle tracking. The GPS satellites were deployed originally for military use, but their signals were made available in downgraded form for commercial users, which number in millions worldwide.

In GPS systems, operators do not have to pay for the vehicle position fixes provided by the GPS satellite systems, but they do have to pay for the GPS receiving unit, antennae, and the radio link used to transmit the vehicle tracking data, which may incur costs in using the radio network.

The Eutelsat satellite-based positioning system also used for tracking vehicles differs from GPS in that it is a privately run operation, and users are charged for satellite usage.

GPS used to be accurate to within 100 metres, but in May 2000 the US Government removed the downgrading known as "selective availability", which improved accuracy to about 20 metres or better. A technique known as differential GPS allows 1 metre accuracy or better by using a ground-based reference signal, although this is normally used for survey applications rather than vehicle tracking.

Suppliers of GPS-based vehicle tracking systems provide on-board receivers that decode high-frequency radio signals emitted by the satellites, and correlate the timing between different satellites, and thereby allow the vehicle tracking system to determine its longitude and latitude, as long as at least three satellites are receivable.

To show the location geographically, the latitude and longitude data from the mobile vehicle tracking system is converted to a symbolic overlay on software that shows a map of the surrounding area. This software may run in the vehicle itself, as in on-board sat-nav dashboard systems, or for a fleet management system on a computer display at the fleet base, where the fleet manager monitors the positions of all vehicles in the fleet.

Vehicle tracking can utilise, not just satellite (e.g. GPS), but also digital cellular telephone networks and low-frequency radio networks. The means by which the tracking information is transmitted back to base may include digital mobile radio networks, private mobile radio systems, and satellite networks. The radio network may interface with land-line, internet or ISDN links to the base.

Cellular mobile telephone networks can also be used to do position fixes by locating vehicles within a cell site, i.e. showing where the vehicle is in relation to the nearest cell site base station. Accuracy varies, depending on the density of cells (there are more cells in towns than in rural areas).

When the base system has captured the data from each vehicle, and it is available on a base station computer, it is then possible to use the Internet to allow users to follow the vehicle tracking information and carry out fleet management from any computer, laptop or handheld device with an internet link.

"The journey, not the arrival, matters." - T. S. Eliot.

References

Here are some useful background references on satellite vehicle tracking:

Dec 28th, 2003 Updated Mar 22nd, 2006