WO2000062211A1

WO2000062211A1 - Method for minimising pollution

Info

Publication number: WO2000062211A1
Application number: PCT/AU2000/000303
Authority: WO
Inventors: Mark Anthony Booth
Original assignee: Autovation Pty Limited
Priority date: 1999-04-07
Filing date: 2000-04-07
Publication date: 2000-10-19
Also published as: AUPP962499A0

Abstract

A method for minimising the impact of motor vehicle emission on the environment and computer software therefore, the method including the steps of: (1) establishing the characteristics (such as performance, load capacity and availability characteristics) required of each vehicle in a fleet of motor vehicles; (2) analysing the tasks assigned to each vehicle in the fleet and determining the minimum vehicle characteristics required for each task; (3) prioritising each of the tasks required to be performed by the vehicles in the fleet; (4) compiling the data obtained from steps (1) to (3); (5) calculating the optimal combination of the assignment of vehicles to tasks; and (6) implementing actions based on a reassignment of the tasks for each vehicle in accordance with the priorities determined in step (3) based on the characteristics identified in step (1) and the analysis in step (2) to improve the efficiency and minimise the total pollution emissions of the fleet. The compilation of data in steps (1) to (4) may be performed using a computer database and the calculations carried out in step (5) may be performed using a computer processor.

Description

METHOD FOR MINIMISING POLLUTION

Technical Field

This invention is concerned with minimising pollution. In particular, this invention relates to a method for minimising pollution caused by motor vehicles. Still more particularly, the invention concerns the minimisation of pollution caused by a fleet of vehicles.

Background Art

The impact on air quality by motor vehicle emissions is considerable. Many attempts have been made to alleviate the impact of these emissions. In some countries, authorities have made it mandatory for newly manufactured vehicles to include emission control apparatus. In other countries, authorities have attempted to reduce the quantity of vehicles entering cities each day.

While such measures may or may not enjoy a measure of success, pollution caused by motor vehicle emission remains a problem. It is helpful at this point to describe the sources of pollution emitted from vehicles in general terms. Pollutant emissions are produced from two main areas of a motor vehicle, namely the exhaust system, as a result of combustion, and the fuel storage and delivery system, as a result of evaporation.

With regard to exhaust system emissions, an internal combustion engine using fossil fuel produces, as a by-product of combustion, carbon monoxide, nitrogen oxides and hydrocarbons. These particular pollutants are produced in different ways. Carbon monoxide is produced from incomplete combustion of the fossil fuel. Nitrogen oxides are formed as a result of the high temperatures associated with combustion. Hydrocarbons are emitted because a certain amount of uncombusted fuel escapes through the exhaust system.

Carbon monoxide and hydrocarbon emissions are at their peak during the period commencing with the initial starting of a vehicle and ending after the first few

Subtitute Sheet (Rule 26) RO/AU minutes of operation. This is called the "cold start mode". Where vehicles are fitted with catalytic emission control systems, such systems do not operate until the vehicle has attained a particular operating temperature. While the vehicle is reaching that operating temperature, a richer fuel-to-air ratio is used to achieve correct performance.

While the fuel-to-air ratio during the cold start mode has little effect on nitrogen oxides emission, during this mode while the emission control system is not operating fully, there is an increase in emission of nitrogen oxides.

Conversely, emission rates of carbon monoxide, nitrogen oxides and hydrocarbons are lower during "hot starts" - i.e. when the engine is ignited shortly after it has been switched off, the engine having maintained a high temperature. Such rates are at their lowest during the "hot stabilised mode" - i.e. during the normal operating mode of the vehicle, after the completion of the cold start mode.

With regard to emissions caused by evaporation, these comprise basically hydrocarbons produced in the fuel storage and the fuel delivery system. The level of emission depends on air temperature. Thus, emissions of hydrocarbons may occur from the carburettor or fuel injection devices when the engine is turned off. Emissions take place from the fuel tank as a result of temperature changes over a 24 hour period. Some emissions occur while the vehicle is being operated, when more fuel is emitted into the emission control canister than the amount of fuel being purged. Hydrocarbon emission can also result from vapour loss from the emission control system or from liquid leaks in the system. Hydrocarbon emission can take place during refuelling of a vehicle, because of spillage or vapour displacement. Hydrocarbon emission from the crank case can also take place if there are defective positive crank case ventilation valves.

Consequently, there is a strong case for the minimisation of those emissions if possible. It is estimated that almost half of air pollution is produced from motor vehicle emissions. Accordingly, there is a need to reduce the overall pollutant

Subtitute Sheet (Rule 26) RO/AU emissions produced by private and publicly run vehicle fleets, which make up a significant proportion of the motor vehicles on the roads.

A vehicle monitoring arrangement and system is described in United States Patent No. 4,804,937. In this disclosure each fleet vehicle includes a data terminal for communicating information to a remote base station. The information communicated includes messages associated with the performance of the vehicle. The system includes (a) a data bus member for electrically intercoupling a plurality of communication modules and for receiving the communicated messages therefrom; (b) a driver interface module for transmitting messages to and from a vehicle operator preferably using an RF link and (c) a recorder coupled to the data bus for recording information associated with the performance of each vehicle.

In United States Patent No. 4,934,419 there is described a fleet data monitoring system for fuel management in which the fuel management system is coupled to a fuel supply means (that is, a fuel pump) for controlling the amount of fuel dispensed via the nozzle. United States Patent No. 5,922,040 describes a method and apparatus for fleet management including a graphical interface user apparatus operably coupled to a mobile information centre which provides vehicle position data and the like.

These disclosures do not provide a means of assessing the general characteristics of each vehicle with a view to utilisation of a fleet to perform various tasks for the purpose of optimising the efficiency of, and reducing pollutant emissions produced by, the fleet.

This invention is based on the premise that further steps can be taken, in relation to motor vehicle fleets, to minimise the impact of motor vehicle emission on the environment.

Subtitute Sheet (Rule 26) RO/AU Disclosure of the Invention

Accordingly, this invention provides, in a first aspect, a method for minimising the impact of motor vehicle emission on the environment, the method including the steps of:

( 1 ) establishing the characteristics of each vehicle in a fleet of motor vehicles;

(2) analysing the tasks assigned to each vehicle in the fleet and determining the minimum vehicle characteristics required for each task;

(3) prioritising each of the tasks required to be performed by the vehicles in the fleet;

(4) compiling the data obtained from steps (1) to (3);

(5) calculating the optimal assignment of the vehicles to the tasks; and

(6) implementing actions based on a reassignment of the tasks for each vehicle in accordance with the priorities determined in step (3) based on the characteristics identified in step (1) and the analysis in step (2) to improve the efficiency, and minimise the total pollution emissions, of the fleet.

The invention may further involve the establishment of a computer database containing the information and data compiled by performing steps (1) to (4). The computer database may be established by the use of dedicated software. The software may be included on one or more pre-recorded computer discs, such as a compact disc or a set of floppy discs, or may be made available by electronic transfer over the internet, or otherwise by remote transfer, whereby the software may be installed on a user's computer.

Accordingly, in a second aspect of the invention, there is provided a computer software system for assigning tasks to vehicles belonging to a fleet, said system being capable of performing the following steps:

Subtitute Sheet (Rule 26) RO/AU (1) receiving data input relating to vehicle characteristics data defining the characteristics of each vehicle in a fleet of motor vehicles;

(2) establishing the minimum vehicle characteristics required for each task assigned to the fleet using criteria including minimum passenger and/or load carrying requirements;

(3) assigning at least one priority value to each task based on an analysis of the tasks;

(4) calculating the optimal combination of the assignment of vehicles to tasks with reference to the minimum vehicle requirements of step (3) and the at least one priority value of step (2); and

(5) implementing actions based on a reassignment of the tasks for each vehicle in accordance with the priorities determined in step (2) to improve the efficiency and minimise the total pollution emissions of the fleet.

The software may be pre-recorded. The software may include information and data relating to the model characteristics and specifications published or otherwise made available by manufacturers of vehicle models likely to be used as fleet cars. The software may be capable of being modified by the user to reflect changes or corrections in vehicle specifications or to take account of customised modifications to vehicles. This may include data sufficient to identify a particular vehicle model or type such as model year, make, model description, transmission, etc., sufficient to identify the specific vehicle type.

Once the vehicle type has been specifically identified, a valid comparison with a standardised set of data may be made on relative performance criteria. For example, performance data may include the distance travelled in city traffic carrying a particular average load, over a specific period of time and the fuel consumption over that period. This data may be used to assess the efficiency of the vehicle's performance compared to either another vehicle in the fleet, the

Subtitute Sheet (Rule 26) RO/AU performance specifications provided by the manufacturer or an independent motorist's association for the same model or an alternative model.

The software may be periodically updated to take account of improvements in the software, existing vehicle models considered on review to be likely fleet candidates and new vehicle models appearing on the market. The software may also be customised to accommodate the peculiar needs of particular users.

The comparison of the performance characteristics of each particular vehicle in the fleet against a standardised set of data may be used to determine whether servicing, maintenance, repairs, modifications or improvements are required. The comparison or the task reassignment may also be used to determine whether the vehicle should be decommissioned from the fleet and/or whether there is a need to introduce one or more other new or used vehicles to the fleet by acquisition.

Periodic assessments of the tasks to be performed in light of the fleet resources may be made daily, to provide a system highly reactive to changes in the tasks to be performed or the make-up of the fleet, or for example monthly, to provide a more stable system.

Moreover, the invention may involve an assessment of other forms of road transport and their suitability for the tasks to be performed. Such out-sourced road transport may include taxi and courier services, freight transport and the like.

Accordingly, in another aspect of this invention there is provided a method for reducing the impact of motor vehicle emission on the environment, the method including the steps of:

(2) analysing the tasks of each vehicle in the fleet;

(3) analysing alternate methods of road transport;

Subtitute Sheet (Rule 26) RO/AU (4) prioritising issues based on the characteristics established in step (1) and the analyses in steps (2) and (3); and

(5) implementing actions in accordance with the issues prioritised in step (4) so as to reduce emissions from motor vehicles in the fleet.

Best Mode of Carrying out the Invention

The step of establishing characteristics of each vehicle in the fleet may involve the compilation of characteristics such as those set out in the inventory sheet in Table 1 on the following page.

Other characteristics may include passenger or load carrying capacity, the existence or not of refrigeration facilities, air conditioning, allocation of the vehicle to a specific driver, group of drivers, department, etc., difficulty of start-up or rate of pollutant emissions during start-up and shortly thereafter, and availability details such as anticipated maintenance, repair or modification down-time.

Many of the data fields on the inventory sheets are self-explanatory. However, it should be mentioned that accessories are an important inclusion, since they can affect fuel economy.

The number of cylinders and the actual litre size of the engine are also important inclusions. In relation to "fuel type", the first field is for the primary fuel used in the vehicle, such as unleaded petrol. The second field is for any secondary fuel source used in the vehicle. For example, the vehicle could be designed to run on a dual fuel system using petroleum and compressed natural gas (CNG) or liquefied petroleum gas (LPG).

The "fuel efficiency city cycle" can comprise a rating supplied by an appropriate organisation, such as the NRMA (National Road Motorists Association). The "fuel efficiency highway cycle" can be sourced similarly.

Subtitute Sheet (Rule 26) RO/AU The term "VIN" refers to "the vehicle identification number" which is located in vehicle registration papers.

The "on system date" is the date the vehicle commenced service.

The annual kilometres driven using purchase date and current speedometer is calculated by dividing the total number of kilometres travelled since the purchase date of the vehicle by the number of months which have elapsed since that date and multiplying by 12 to calculate the annual rate.

Subtitute Sheet (Rule 26) RO/AU

Subtitute Sheet (Rule 26) RO/AU

The calculation of annual kilometres driven is made using the last two odometer readings and the dates defining the relevant period which allows for measurement of the average kilometres for the past year and provides a check on current trends for the vehicle.

A benchmark for each particular vehicle is established by the "annual fuel consumption using the NRMA fuel efficient ratings". The litres of fuel per hundred kilometres are chosen according to whether the vehicle is driven mainly in the city or mainly on the highway, having regard to the "fuel efficiency city cycle" and "fuel efficiency highway cycle" data fields referred to above. The consumption rate is then multiplied by the annual kilometres driven to arrive at annual fuel consumption figures. Compared against this benchmark figure is the actual annual and life-to-date fuel consumption of the appropriate fuel (for example, unleaded petrol (ULP), diesel, LPG or CNG).

Vehicle maintenance costs can be calculated from records kept for the vehicle.

The step concerning the analysis of the tasks assigned to each vehicle in the fleet requires that the minimum vehicle or transport requirements for each task be determined. This can help to determine whether an alternate transport option is available. An example of a table showing data relating to vehicle use is set out below in Table 2.

Subtitute Sheet (Rule 26) RO/AU

At the same time, in line with step (3) in the second aspect of the invention, the use of other forms of transport already being made may be assessed. These can include personal vehicles, hire vehicles, short term leases, taxis, buses and trains, for example. An example of a table collating this kind of data is set out below in Table 3.

Subtitute Sheet (Rule 26) RO/AU

The total cost of personal vehicle use can be calculated by dividing the total cost by the average kilometre rate paid to the driver and dividing the total days of vehicle use by the average kilometres. This provides an insight into the cost-to-time ratio for each kilometre travelled. Similarly, in the case of hire cars, the total days can be determined by dividing the total cost by agreed hire rate. The total kilometres can be calculated by multiplying the total days by the average kilometres driven. In the case of taxis, the total days can be determined by dividing the total cost by an estimated round trip taxi fare and the total kilometres can be determined by multiplying the total cost by the average kilometres per round trip taxi use.

Subtitute Sheet (Rule 26) RO/AU Analysis of the fleet can show whether the correct vehicle is being assigned to the appropriate task and whether vehicles are being used to maximum capacity.

It is optional to develop a strategy or policy in relation to the motor vehicle fleet. Such a policy may relate to the selection or allocation of vehicles to management personnel, maintenance, repair and servicing regimens, driver training to optimise efficiency and minimise fuel emissions and the like.

The next step involves prioritising the tasks to be performed or the issues to be considered. In this regard, it should be appreciated that each vehicle in a fleet will give rise to a certain basic cost per year.

If there is increased utilisation of vehicles in the fleet, to optimum effect, the cost per day can decrease and the cost per kilometre can decrease. Further, if it is feasible to increase utilisation of vehicles in a fleet, it becomes more cost effective to look at converting to alternate fuel sources, such as CNG, since the capital cost of conversion is paid back through faster fuel savings.

In addition to defining the physical, time, and human resource requirements for each task, the tasks to be performed may be assigned a value whereby to rate their relative importance and establish differential priority values. The priority value may be a numerical value or some other abstract valuation system. Preferably, the priority value is able to be processed by a computer processor. Preferably, no two tasks can share the same priority value. Preferably, the tasks are classified according to the minimum vehicle specifications required to perform the task. Generally, this will involve the categorisation of tasks into classes of tasks corresponding to the particular vehicle or vehicle type required. Based on priorities of tasks categorised within a particular class, the recommendation may be to either purchase more vehicles of that class, or to re-assign a lower ranked task to a different, less preferred class of vehicles. A task may require a vehicle to remain idle in readiness for an emergency delivery, etc.

Subtitute Sheet (Rule 26) RO/AU As an example of the allocation of priorities values to different tasks, a first task may be to deliver 100 kilograms of dough to client A and a second task may be to deliver 300 kilograms of raw sugar to client B. Based on criteria such as client A's superior account attributes including higher turnover or reliability in paying accounts, or client A's propensity to stock minimum amounts of product, or the perishable nature of the product, the first task may be assigned a numerical priority value of 80 and the second task a lower value of 50.

The criteria on which task priorities are based may include flexibility in the type of vehicles which may be used, refrigeration or heating requirements, perishability of goods to be transported, customer priorities, punctuality requirements and the like.

It may be a priority to integrate all modes of available transport. For example, an arrangement with a taxi company may be more environmentally and economically sound than using a vehicle from the fleet and incurring costs for parking, etc.

Another issue to be prioritised is the selection of the correct vehicle for the correct application. For example, the step involving the analysis of the tasks may show that a particular vehicle is used for 90% of the time for normal driving and for 10% of the time for driving over rough terrain when a 4 wheel drive vehicle is required. In this circumstance, it may be more environmentally friendly to utilise a 2 wheel drive vehicle for the normal driving time and hire or share with another entity the use of a four wheel drive vehicle for the 10% rough driving required.

Generally, prioritising of issues will require that the smallest vehicle possible is selected for the assigned task. In doing this, it is necessary to ensure that the passenger and cargo areas meet requirements. The most fuel efficient vehicle possible should be selected. For example, a particular vehicle may be operated using low-sulfur diesel fuel, methanol, CNG or LPG as appropriate where cost effective and operationally possible to decrease the level of pollution emitted by the vehicle.

Subtitute Sheet (Rule 26) RO/AU Low-sulfur diesel fuel is environmentally preferable to regular diesel fuel because of its lower sulfur content, whilst having the same energy content as regular diesel. The use of lower sulfur diesel fuel results in reduced sulfur-dioxide emissions, produces less sulfur particles or soot and can be used in most existing diesel engines. Unfortunately, its lack of availability in some areas may render it impractical.

Methanol has gained some currency as a vehicle fuel in the United States because it may be sourced from natural gas and recycled waste including renewable energy sources such as wood wastes. Vehicles must be specially manufactured for use of methanol as a fuel because of its corrosive nature. The use of methanol in a mixture with unleaded petrol (ULP) results reduced hydrocarbon, carbon monoxide and nitrogen oxide emissions and there is less potential for the formation of ground-level ozone.

Compressed natural gas has been established as a cooking and domestic heating fuel for many years. However, it is now being considered as a serious alternative to ULP. Compared to ULP, use of CNG results in reduced hydrocarbon, carbon monoxide, carbon dioxide and nitrogen oxide emissions, there is less potential for the formation of ground-level ozone and results in the release of less toxic compounds. Again, however, its availability is limited in many areas.

Liquid petroleum gas is well established as a cheaper alternative to ULP for use in high mileage vehicles because of the savings in fuel costs. LPG conversion kits are common in standard domestic vehicles, such as four wheel drives, and smaller commercial vehicles, such as taxis. Compared to ULP, use of LPG results in reduced carbon monoxide, carbon dioxide and nitrogen oxide emissions and there is less potential for the formation of ground-level ozone. LPG also burns cleaner than conventional fuels, reducing the maintenance frequency required for spark plugs and engine oil replacement. There is wide availability of LPG, particularly in metropolitan areas of most major cities.

Subtitute Sheet (Rule 26) RO/AU As an example of the effect the use of different fuels has on the efficiency of a vehicle performing a task, and on its attendant environmental impact, the Table 4 shows the difference in fuel consumption by using different vehicles capable of carrying out the same task. The estimated annual travel is 25,000 kilometres per year and the average price of unleaded fuel is $0.70 cents per litre. It will be seen that the 2.2 litre model can affect a fuel saving of 29% compared to the 5.0 litre model. Obviously, the substantial reduction in fuel consumption will result in a lower level of pollutant emissions.

As indicated above, vehicles operated by CNG should be used where cost effective and operationally possible. This can be looked at from two perspectives. The first is the purchase of a vehicle which is designed for using CNG by the original equipment manufacturer.

Subtitute Sheet (Rule 26) RO/AU The second is to examine which vehicles can be converted to CNG use. When considering a switch to CNG use, it should be determined that the conversion will be cost effective and will deliver a life cycle cost equal to or lower than the equivalent unleaded petrol or diesel powered vehicle. Operational feasibility should include a consideration of the availability for CNG delivery within the area of operation and the range of the vehicle, whether correct service and repair support is available, the reliability of the vehicle for the operating conditions and so on.

The next step is the implementation step and an action plan may be created at this stage. Such a plan may link to goals and objectives, appoint individuals to manage the plan, set deadlines and assign a budget.

Where a computer database is used in accordance with the invention, based on the data entered into the database, the software may prepare a set of directions regarding the allocation of resources to the tasks required to be performed on the basis of the established priorities.

For example, assume the task is to transport a cubic meter of stationery goods 10 km from a warehouse to a retail outlet each Thursday. The current mode of transport for all freight transported in the local area is a standard 3 tonne diesel powered truck which is used throughout the week for most of the freight transport needs due to its convenient capacity to carry a wide range of load volumes and tonnage. On the other days of the week the freight requirements are significantly higher. However, within the large fleet of vehicles available to the operator, there is a 2 litre van having a carrying capacity of 4 cubic meters which is run on LPG and is used by the assistant accountant for the 2 km bank run on each weekday morning. The assistant accountant prefers the van to a 1.2 litre ULP powered sedan because the latter is considered "too small". When the characteristics, such as load carrying capacity and type of fuel used, of each vehicle in the fleet is entered on the database, and matched with the various tasks to be performed by the fleet, rated according to their priorities and optionally with a specified time range in which

Subtitute Sheet (Rule 26) RO/AU each task is to be performed, directions will be generated by the software. In this example, assuming no other factors are considered, the operator will be required to use the 2 litre van, the assistant accountant will be required to use the 1.2 litre sedan for the bank run and the 3 tonne truck will lie idle on Thursday mornings.

Another type of implementation relates to vehicle purchasing. It will be recalled from the characteristic and tasks steps that the task or tasks of the vehicle are to be analysed and the feasibility of an alternate transport option assessed. If, having regard to those factors, there is still a need for the purchase of a vehicle, the vehicle which is the most fuel efficient and most operationally efficient should be purchased. Generally, the vehicle having a small engine size while still accommodating the required number of passengers and having the desired cargo capacity will be most appropriate.

Vehicle service and maintenance can be implemented so as to minimise excessive fuel use and operational expenses. For example, it is recommended that the following be checked on a monthly basis:

(a) Hoses to radiator and heater are inspected for leaks and cracks;

(b) The radiator overflow bottle is inspected for correct level of coolant;

(c) The lubrication system is checked for leaks, especially around and under the engine;

(d) The battery terminals on the battery are checked for corrosion and cleaned, if necessary. Any damaged or worn wired or cables are replaced;

(e) The drive belts for the fan, air pump, alternator, air conditioning system, power steering, etc. are checked to ensure that they are at the correct tension. Any frayed or cracked belts are replaced;

(f) The vehicle is inspected for any leaks left on the ground and the source is repaired.

Subtitute Sheet (Rule 26) RO/AU —

19

The aspects below should also be implemented periodically.

The vehicle should be tuned by a qualified technician.

Filters designed to ensure that clean air and fuel enter the engine should be inspected and replaced if necessary. A clogged filter may cause up to a 10% increase in fuel consumption.

The oil in the engine should be changed in order to reduce excessive wear, remove acids, sludge and other harmful substances and to help cool the engine, preventing the engine from rusting. Neglecting to do this results in excessive wear of the motor, causing increased friction which in turn causes increased fuel consumption. The oil filter should be replaced at the same time. The correct motor oil for the engine should be used.

The tyres on the vehicle should be rotated front to rear to obtain maximum wear and the tyre pressure should be checked every week when the tyres are cold. If a single tyre is under-inflated by 21bs per square inch, it can cause a 1% increase in fuel consumption.

The braking system should be inspected by a qualified technician and adjusted or repaired as necessary. If brakes lock on or cause drag, the engine may be caused to work harder, thus increasing fuel consumption.

Any emission control system should be checked to avoid a decline in performance or an increase in emission.

Another form of implementation is the education of drivers to adopt a driving practice which minimises emissions. For example, drivers can be educated to use steady acceleration and moderate speeds in order to lower fuel consumption. Route management can assist drivers to find the shortest route. Adequate planning can eliminate unnecessary trips or reduce the number of trips. Staff can be assisted to travel in off-peak times. The management of the fleet can be planned to ensure that vehicles are idle as little as possible.

Subtitute Sheet (Rule 26) RO/AU The word "comprise" and its derivatives, as used throughout the specification and claims, is to be construed as having an inclusive meaning, whereby a group preceded by the word is considered to possibly contain more than merely the elements, steps or integers explicitly listed as members of the group.

It will be appreciated that the present invention represents a significant step forward in the art and is capable of substantially reducing motor vehicle emission. It will also be appreciated that the examples given are not limiting on the scope of the invention.

Industrial Applicability

The invention provides a method and a system for optimising the efficiency of a fleet of vehicles whereby to minimise the pollution produced by the fleet for a given set of tasks.

Subtitute Sheet (Rule 26) RO/AU

Claims

The Claims

1. A method for minimising the impact of motor vehicle emission on the environment, the method including the steps of:

(4) compiling the data obtained from steps (1) to (3);

(5) calculating the optimal assignment of the vehicles to the tasks; and

2. A method according to claim 1, wherein the characteristics in step (1) include performance characteristics including distance travelled for amount of fuel consumed, fuel type and load capacity and other characteristics including availability, dedication to particular personnel and down-time periods due to maintenance, repairs and/or improvements.

3. A method according to claim 1 , wherein the tasks in step (2) include tasks relating to passenger and freight transport including distances to be travelled and passenger and/or load capacity required.

4. A method according to claim 3, wherein the tasks in step (3) are prioritised by the categorisation of the task according to the class of vehicle satisfying the

Subtitute Sheet (Rule 26) RO/AU task's minimum vehicle requirements and the allocation of at least one priority value to each task.

5. A method according to claim 4, wherein the priority value calculation is based on criteria including refrigeration or heating requirements, perishability of goods to be transported, customer priorities, punctuality requirements and flexibility in the type of vehicles which may be used.

6. A method according to claim 4, wherein the at least one priority value is a numerical value.

7. A method according to claim 1, wherein compilation in step (4) is performed by the entering the data obtained in steps (1) to (3) into a computer database and the calculation in step (5) is performed using a computer processor.

8. A computer software system for assigning tasks to vehicles belonging to a fleet of vehicles, said system being capable of performing the following steps:

(1) receiving data input relating to vehicle characteristics data defining the characteristics of each vehicle in the fleet;

Subtitute Sheet (Rule 26) RO/AU

9. A system according to claim 8, wherein each task in step (2) is classified according to the class of vehicle satisfying the task's minimum vehicle requirements.

10. A system according to claim 8, wherein the at least one priority value in step (3) is a numerical value.

Subtitute Sheet (Rule 26) RO/AU