CN114458429B

CN114458429B - Calibration method, calibration module and readable storage medium for enhancing passive regeneration of particle trap

Info

Publication number: CN114458429B
Application number: CN202011238599.4A
Authority: CN
Inventors: 吴淑梅
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2020-11-09
Filing date: 2020-11-09
Publication date: 2025-10-28
Anticipated expiration: 2040-11-09
Also published as: CN114458429A

Abstract

The present application relates to a calibration method for enhancing passive regeneration of a DPF (48) of an exhaust gas aftertreatment system, the system comprising a close-coupled aftertreatment system (20) having a first SCR (24) and an underground aftertreatment system (40) comprising the DPF (48) and a second SCR (44) located downstream of the DPF (48). The method comprises: a first step (S1) of determining a calibration factor (F) by looking up a calibration factor table or curve based on a concentration ratio of _NO2 and soot (R _NO2/Soot ) in exhaust gas upstream of the DPF (48), a soot level ( _LS ) inside the DPF (48), and an exhaust gas temperature upstream of the DPF (48) (T _48UP ); and a second step (S2) of applying the calibration factor (F) to a first urea metered injection amount (M _25ini ) to be injected into the exhaust gas upstream of the first SCR (24), thereby obtaining a first urea calibration injection amount (M _25cor ). The present application also relates to a calibration module including a processor and a memory storing executable instructions, and a readable storage medium storing executable instructions, which enables a machine to perform the above-mentioned calibration method when the executable instructions are executed.

Description

Calibration method, calibration module and readable storage medium for enhancing passive regeneration of particle trap

Technical Field

The present application relates to the field of vehicle exhaust aftertreatment, and in particular to a calibration method for enhancing passive regeneration of a particle trap (abbreviated herein as DPF) of an exhaust aftertreatment system (abbreviated herein as ATS). The application also relates to a calibration module and a readable storage medium for performing the method.

Background

In order to meet the increasingly stringent vehicle exhaust requirements of countries around the world, various exhaust aftertreatment systems have been developed to reduce the amount of NO _X and particulate matter emitted to the atmosphere by vehicles, particularly diesel vehicles.

To minimize the NO _X emitted to the atmosphere, the exhaust aftertreatment system may include a low temperature or Close coupled aftertreatment system (Close coupled ATS or cc-ATS) and an underground aftertreatment system (Under Floor ATS or uf-ATS), with the cc-ATS located upstream of the uf-ATS. Exhaust from the engine first enters the cc-ATS, where it is reduced and a portion of the NO _X content in the exhaust is eliminated by a first selective catalytic reduction device (herein simply SCR). The exhaust gas, in which the NO _X content is reduced, then enters the uf-ATS, where it is reduced and another or second portion of the remaining NO _X content in the exhaust gas is eliminated by the second SCR therein. The exhaust gas after being discharged from the uf-ATS is directly discharged to the atmosphere, at which time the residual NO _X content in the exhaust gas needs to satisfy a specific content threshold corresponding to a specific emission requirement.

In addition to including the second SCR, the uf-ATS also includes a DPF for capturing, and thereby removing, at least some or all of the particulates in the exhaust gas. It is well known that in order to ensure the ability or efficiency of a particle trap to adsorb or trap particles, a DPF requires removal of accumulated particles by means of regeneration. Active regeneration of a DPF requires injection of fuel into the exhaust gas, with the assistance of which particulate combustion is performed.

Currently, the amount of reductant-urea injected to the first SCR and the second SCR is typically determined based on the NO _X content in the exhaust gas entering the cc-ATS and uf-ATS, respectively, and does not take into account factors of DPF regeneration. It is desirable to be able to enhance the passive regeneration of the DPF to reduce the necessary active regeneration.

Disclosure of Invention

The application aims to enhance or promote the passive regeneration of DPF, so as to reduce the necessary active regeneration and save fuel.

According to a first aspect of the present application, there is provided a calibration method for enhancing passive regeneration of a DPF of an exhaust aftertreatment system, wherein the exhaust aftertreatment system comprises a close-coupled aftertreatment system with a first SCR and an underground aftertreatment system comprising the DPF and a second SCR located downstream of the DPF, the method comprising the steps of:

A first step of determining a calibration factor by querying a calibration factor table or curve based on a concentration ratio of NO ₂ and soot in exhaust upstream from the DPF, a soot level inside the DPF, an upstream exhaust temperature of the DPF;

a second step of applying the calibration factor to a first urea dosing injection to be injected into exhaust upstream of the first SCR, resulting in a first urea calibration injection;

A third step of obtaining the efficiency of the close-coupled aftertreatment system or the NOx content in the exhaust gas upstream of the underground aftertreatment system based on the first urea calibration injection quantity;

A fourth step of determining a second urea metered injection quantity to be injected into the exhaust upstream of a second SCR of the underground aftertreatment system based on the efficiency or the NOx content in the exhaust upstream of the underground aftertreatment system and an allowable NOx content threshold corresponding to a specific emission requirement;

A fifth step of determining whether a final NOx content in the exhaust gas discharged from the underground aftertreatment system is within an allowable NOx content threshold;

a sixth ending step when the final NOx content is less than or equal to the allowable NOx content threshold.

According to a second aspect of the present application, there is provided a calibration module comprising:

processor, and

A memory storing executable instructions that when executed cause the processor to perform the calibration method described above.

According to a third aspect of the present application there is provided a readable storage medium having stored thereon executable instructions which when executed cause a machine to perform the above-described calibration method.

As described above, according to the present application, by reducing the first urea injection amount, the amount of NO _X that can be reduced or removed by the selective reduction catalyst device of the close-coupled aftertreatment system of the aftertreatment system is reduced, so that the amount of NO _X in the exhaust gas entering the underground aftertreatment system is increased, which is beneficial to passive regeneration of the particle catcher, and accordingly, the number of necessary active regeneration is reduced or the active regeneration interval of the particle catcher is prolonged, the amount of fuel required for auxiliary active regeneration is reduced, and the purpose of saving fuel is achieved.

Drawings

The above and other features and advantages of the present application will become apparent from the following detailed description given with reference to the accompanying drawings.

FIG. 1 is a schematic simplified block diagram of a vehicle exhaust aftertreatment system of the present disclosure;

FIG. 2 is a flow chart of a calibration method for enhancing passive regeneration of a particle trap of an underground aftertreatment system of a vehicle aftertreatment system, in accordance with an embodiment of the present application;

FIG. 3 schematically illustrates a schematic diagram of a calibration algorithm of the calibration method of FIG. 2;

FIGS. 4a and 4b are examples of a first sub-calibration factor table and a second sub-calibration factor table, respectively;

Fig. 5 schematically shows a schematic of a calibration module for performing the method of fig. 2.

Detailed Description

The principles of the present invention are described in detail below with reference to the embodiments shown in the drawings. It will be appreciated by those skilled in the art that these examples are illustrative only and are not intended to limit the invention in any way.

The present application is directed to an exhaust aftertreatment system including a low temperature or close coupled aftertreatment system (cc-ATS) 20 and an underground aftertreatment system (uf-ATS) 40.

FIG. 1 illustrates a schematic simplified block diagram of an exhaust aftertreatment system, according to an embodiment of the present disclosure. The vehicle engine 10 is shown, and exhaust gas discharged from the engine 10 flows in the exhaust pipe 15 in the flow direction D. The exhaust pipe 15 is provided with the exhaust gas aftertreatment system described above. Herein, the direction in which the exhaust gas from the engine 10 flows in the exhaust pipe 15 is indicated by D (solid arrow), and the terms "upstream" and "downstream" are used herein with respect to the direction D in which the exhaust gas flows in the exhaust pipe 15. For example, in an exhaust aftertreatment system of the present disclosure, a first component disposed upstream of a second component or a second component disposed downstream of the first component means that exhaust from engine 10 enters the first component first and then enters the second component. In addition, those skilled in the art will understand that the term "comprising" or "comprises" has an open-ended meaning that it may include additional unlisted objects in addition to the objects following the term.

As shown in FIG. 1, the exhaust aftertreatment system of the application includes a cc-ATS 20 with a first selective catalytic reduction device (SCR) 24 and a uf-ATS 40 with a second selective catalytic reduction device (SCR) 44. The lower temperature exhaust gas produced upon initial start-up of the engine 10 is primarily treated by the cc-ATS 20, while the higher temperature exhaust gas produced upon normal operation of the engine is primarily treated by the uf-ATS 40. However, in general, the cc-ATS 20 and uf-ATS 40 act simultaneously, exhaust from the engine 10 first enters the cc-ATS 20 through its first SCR 24 for partial NO _X reduction, then the partially NOx reduced exhaust exiting the cc-ATS 20 then enters the uf-ATS 40 through its second SCR 44 for residual NOx reduction, and finally the exhaust exiting the uf-ATS 40 is vented directly to the atmosphere.

As shown in fig. 1, in addition to including a first SCR 24, the cc-ATS 20 may include a first oxidation catalyst (abbreviated DOC) 22 upstream of the first SCR 24 and a first ammonia slip catalyst (abbreviated ASC) 26 downstream of the first SCR 24. In addition to including the second SCR 44, the uf-ATS 40 may also include a second oxidation catalyst (DOC) 42 and a diesel particulate trap (DPF) 48 upstream of the second SCR 44 and a second Ammonia Slip Catalyst (ASC) 46 downstream of the second SCR 44. The first DOC 22 and the second DOC 42 are configured to convert carbon monoxide (CO), hydrocarbons (HC) and Nitric Oxide (NO) in the flowing exhaust gas into harmless water (H ₂ 0), carbon dioxide (CO ₂) and nitrogen dioxide (NO ₂), respectively, through an oxidation reaction. The first and second ASCs 26, 46 are disposed downstream of the first and second SCRs 24, 44, respectively, for reducing ammonia (NH ₃) slip in the exhaust downstream of the SCRs by catalytic oxidation. The DPF 48 of the uf-ATS 40 is disposed between the second DOC 42 and the second SCR 44 for adsorbing and removing particulates from the exhaust gas flowing therethrough.

In the aftertreatment system of FIG. 1, a first urea dosing and injection device 25 that injects a reductant, such as urea, upstream of the first SCR 24 of the cc-ATS 20 to chemically react with NO _X in the exhaust gas in the first SCR 24 to remove NO _X, and a second urea dosing and injection device 45 that injects a reductant upstream of the second SCR 44 of the uf-ATS 40 to chemically react with NO _X in the exhaust gas in the second SCR 44 to remove NO _X are also included. The first and second urea dosing and injection devices 25, 45 may be or include dosing valves.

Although not shown in FIG. 1, it will be appreciated by those skilled in the art that the exhaust aftertreatment system of the application also includes one or more sensors for measurement purposes, such as, for example, including, but not limited to, one or more temperature sensors that measure exhaust temperature at one or more locations in the exhaust pipe 15, one or more NO _X concentration sensors that measure NO _X concentration in the exhaust gas at one or more locations in the exhaust pipe 15, and so forth. In one embodiment, the exhaust aftertreatment system may include a temperature sensor and a NO _X concentration sensor that measure the temperature and the NO _X concentration of the exhaust gas as it exits the engine 10, a temperature sensor and a NO _X concentration sensor that measure the temperature and the NO _X concentration of the exhaust gas as it exits the cc-ATS 20, and a NOx concentration sensor that ultimately emits the NO _X concentration from the aftertreatment system of the present application into the atmosphere, i.e., as it exits the uf-ATS 40. Of course, sensors for measuring the temperature, O ₂ concentration or NOx concentration, ammonia concentration, particulates, etc. of exhaust gas entering any component (first DOC 22, first SCR 24, first ASC 26, second DOC 24, second SCR 44, second ASC 46, dpf 48, etc.) and exiting any component may also be provided as desired.

The present application, taking into account the effect of NOx content in the exhaust gas on the passive regeneration of the DPF 48, provides a new calibration method for enhancing the passive regeneration of the DPF 48 of the uf-ATS 40 and thus reducing the active regeneration process by varying the amount of urea in the exhaust gas upstream of the first SCR 24 injected by the first urea metering and injection device 25 to the cc-ATS 20. Specifically, the present application imparts a calibration factor F to the urea injection quantity determined by the first urea dosing and injection device 25. Fig. 2 shows a flow chart of the calibration method, and fig. 3 schematically shows a schematic diagram of a calibration algorithm of the calibration method of the present application. The calibration method of the present application for enhancing the passive regeneration of the DPF 48 of the uf-ATS 40 is described below in conjunction with FIGS. 2 and 3.

The calibration method of the present application mainly includes a step S1 of determining a calibration factor F and a step S2 of applying the calibration factor F to the first urea metered injection quantity M _25ini to correct it. Here, the first urea metered injection quantity M _25ini may be determined based on the NO _X content N _20UP in the exhaust upstream of the cc-ATS 20, the temperature T _24UP of the exhaust upstream of the first SCR 24, and other parameters including the amount FL of exhaust exiting the engine 10. Herein, upstream exhaust of a component refers to exhaust entering the component, and downstream exhaust of a component refers to exhaust exiting the component.

Wherein the step S1 of determining the calibration factor F is obtained by looking up a calibration table or a calibration curve based on the ratio R _NO2/Soot of the NO ₂ and the smoke content in the exhaust gas upstream from the DPF 48, the smoke level L _S inside the DPF 48, and the upstream exhaust gas temperature T _48UP of the DPF 48.

Where the soot level L _S in the DPF refers to the amount of soot that has accumulated in the DPF. Firstly, the total Soot level or the total Soot amount discharged by the engine is obtained by inquiring a calibration table or a curve based on the engine speed and the fuel quantity injected into the engine, the first Soot amount consumed by the passive regeneration of the DPF 48 is obtained by inquiring the calibration table or the curve based on parameters such as the engine exhaust quantity FL and the upstream exhaust temperature T _42UP of the second DOC 42, the second Soot amount consumed by the active regeneration of the DPF 48 is obtained by inquiring the calibration table or the curve based on parameters such as the concentration of O ₂ in the upstream exhaust of the DPF 48, the engine exhaust quantity FL and the upstream exhaust temperature T _48UP of the DPF 48, and then the first Soot amount and the second Soot amount consumed by the DPF 48 are subtracted from the total Soot level or the total Soot amount, so as to obtain the Soot level L _S inside the DPF 48.

Wherein, the calibration table or the calibration curve is summarized according to the record of experiments and is obtained by preparing a calibration factor table or curve.

As described above, the calibration factor F is determined based on three parameters of R _NO2/Soot、L_S, and T _48UP, and therefore, the calibration table or calibration curve may be a three-dimensional table or curve based on the three parameters.

Alternatively, for easier illustration and easier operation, two-dimensional table forms may be adopted, that is, the first factor F1 is obtained based on two of the above three parameters, the second factor F2 is obtained based on different two of the above three parameters, and then the calibration factor F is obtained by the first factor F1 and the second factor F2, for example, the calibration factor F is equal to the product of the first factor F1 and the second factor F2. The first factor F1 and the second factor F2 are both in the range of 0 and 1, so the calibration factor F is a value not less than 0 and not more than 1.

Fig. 4a and 4b show an exemplary first sub-calibration factor table based on a first factor F1 calibrated based on the soot level L _S in the DPF 48 and the exhaust temperature T _48UP upstream of the DPF 48, and an exemplary second sub-calibration factor table based on a second factor F2 calibrated based on R _NO2/Soot and the exhaust temperature T _48UP upstream of the DPF 48, respectively, described above. For example, the first factor F1 is 0.14 when the soot level L _S in the DPF 48 is 20g and the exhaust temperature T _48UP upstream of the DPF 48 is 300 ℃, and the second factor F2 is 0.07 when R _NO2/Soot is 50 and the exhaust temperature T _48UP 300 ℃ upstream of the DPF 48, at which time the calibration factor F is 0.0098.

At this time, the step S1 of determining the calibration factor F includes:

Step S11, obtaining a smoke level L _S in the DPF 48 and an exhaust temperature T _48UP upstream of the DPF 48 and querying a first sub-calibration factor table of FIG. 4a to determine a first factor F1;

Step S12, obtaining the exhaust temperature T _48UP upstream of the DPF 48 and R _NO2/Soot and the exhaust temperature T _48UP and looking up the second sub-calibration factor table of FIG. 4b to determine a second factor F2, and

Step S13, multiplying the first factor F1 and the second factor F2 to obtain the calibration factor F.

After the calibration factor F is obtained, in step S2, the first urea metering injection quantity M _25ini determined by the first urea metering and injection device 25 is obtained and multiplied by this calibration factor F, resulting in a first urea calibration injection quantity M _25cor.

Because the calibration factor F is a value less than or equal to 1 in the range of 0-1, the first urea calibration injection quantity M _25cor is typically less than or equal to the first urea dosing injection quantity M _25ini, i.e., the quantity of urea injected into the exhaust gas upstream of the first SCR 24 of the cc-ATS 20 is reduced. Thus, the amount of NO _X that the first SCR 24 of the cc-ATS 20 can remove by the reduction reaction decreases, and the NOx content N _40up in the exhaust gas exiting the cc-ATS 20 and entering the uf-ATS 40 increases. The increased NOx content in the exhaust facilitates passive regeneration of the DPF 48 of the uf-ATS 40.

The calibration method of the present application further includes, after determining the first urea calibration injection quantity M _25cor in step S2:

Step S3, obtaining the NOx content of the efficiency eta ₂₀ of the cc-ATS 20 or the upstream exhaust gas of the uf-ATS 40 based on the first urea calibration injection quantity M _25cor, wherein the NOx content is the NOx content N _40up of the exhaust gas entering the uf-ATS 40;

Step S4, determining a second urea metered injection amount M ₄₅ required for the uf-ATS 40 based on the efficiency η ₂₀ of the cc-ATS 20 or the NOx content N _40up in the exhaust upstream of the uf-ATS 40 and an allowable NOx content threshold T _threshold corresponding to the specific emission requirements;

In step S5, it is determined whether the NOx content N _final in the exhaust gas discharged from the uf-ATS 40, specifically from the second ASC 46, meets the specific emission requirements, i.e., is within the allowable NOx content threshold N _threshold. If N _final is less than or equal to N _threshold, the specific emission requirements are met and step S6 is executed to end the process. Otherwise, if N _final exceeds or is greater than N _threshold, step S7 is performed.

In step S7, the urea quantity M _25ini, in particular the increase, determined by the first urea dosing and injection device 25 is updated on the basis of N _final and N _threshold. The method flowchart of fig. 2 is then repeatedly executed starting from step S1.

According to the calibration method of the application, a calibration factor in the range of 0-1 is provided for modifying, in particular reducing, the amount of urea in the exhaust gas upstream of the first SCR injected into the close-coupled aftertreatment system, reducing the amount of NOx that the first SCR is able to reduce, based on some real-time parameters of the engine and of the exhaust gas emitted from the engine. In this way, the NOx content of the exhaust gas entering the DPF of the underground aftertreatment system downstream of the closely coupled aftertreatment system increases, promoting passive regeneration of the DPF. The increase in passive regeneration reduces the need for active regeneration, correspondingly saving the fuel required for active regeneration.

At least some of the steps of the methods of the present invention may be implemented using a combination of hardware and software. When the method of the present invention is implemented or partially implemented using software, the software may be used to perform various steps of the method of the present invention. The required software and data may be stored in memory and executed by a suitable instruction execution system, apparatus, or device (e.g., a single-core or multi-core processor or microprocessor or processor system). The software may include a list of executable instructions arranged to implement logical functions, which may be embodied in any "processor readable medium" for use by an instruction execution system, apparatus, or device. These systems may access these instructions and execute these instructions.

Some or all of the steps of the above-described method may be performed by a calibration module 50 as shown in fig. 5, which calibration module 50 may be integrated into an Electronic Control Unit (ECU) of the vehicle, i.e. the above-described method may be performed by the electronic control unit of the vehicle.

It should be understood that the calibration module 50 may also be provided independently of the electronic control unit of the vehicle, for example, the control module 50 may be a single-chip microcomputer. The control module 50 may include a processor 52 and a memory 54 storing executable instructions and algorithms for the various computing steps.

The calibration module 50 may communicate directly with the relevant sensors to obtain the parameters required for the steps, or may obtain the parameters from a vehicle Electronic Control Unit (ECU) communicatively coupled to the sensors. When the executable instructions in the memory 54 of the calibration module 50 are executed, the processor 52 obtains the parameters required for calculation from the various sensors or vehicle ECUs and retrieves the associated algorithms from the memory 54 to perform the calibration method as shown in fig. 2 and 3 in turn.

The invention has been described in detail with reference to specific embodiments thereof. It will be apparent that the embodiments described above and shown in the drawings are to be understood as illustrative and not limiting of the invention. It will be apparent to those skilled in the art that various modifications or variations can be made in the present invention without departing from the spirit thereof, and that such modifications or variations do not depart from the scope of the invention.

Claims

1. A calibration method for enhancing passive regeneration of a DPF (48) of an exhaust aftertreatment system, wherein the exhaust aftertreatment system comprises a close-coupled aftertreatment system (20) with a first SCR (24) and a subsurface aftertreatment system (40) comprising the DPF (48) and a second SCR (44) downstream of the DPF (48), the method comprising the steps of:

A first step (S1) of determining a calibration factor (F) by querying a calibration factor table or curve based on a concentration ratio R _NO2/Soot of NO ₂ and soot in exhaust gas upstream from the DPF (48), a soot level L _S inside the DPF (48), and an upstream exhaust gas temperature T _48UP of the DPF (48);

a second step (S2) of applying the calibration factor (F) to a first urea metered injection quantity M _25ini to be injected into the exhaust gas upstream of the first SCR (24), resulting in a first urea calibrated injection quantity M _25cor;

A third step (S3) of obtaining the efficiency η ₂₀ of the closely-coupled aftertreatment system (20) or the NOx content N _40up in the exhaust gas upstream of the underground aftertreatment system (40) based on the first urea calibration injection quantity M _25cor;

a fourth step (S4) of determining a second urea metered injection quantity M ₄₅ to be injected into the exhaust gas upstream of a second SCR (44) of the underground aftertreatment system (40) based on the efficiency η ₂₀ or the NOx content N _40up in the exhaust gas upstream of the underground aftertreatment system (40) and an allowable NOx content threshold T _threshold corresponding to a specific emission requirement;

A fifth step (S5) of determining whether or not a final NOx content N _final in the exhaust gas discharged from the underground aftertreatment system (40) is within an allowable NOx content threshold N _threshold;

A sixth ending step (S6) when the final NOx content N _final is less than or equal to the allowable NOx content threshold N _threshold.

2. The calibration method according to claim 1, further comprising a seventh step (S7) of updating the first urea metered injection quantity M _25ini based on the final NOx content N _final and a permissible NOx content threshold N _threshold when the final NOx content N _final is greater than a permissible NOx content threshold N _threshold.

3. The calibration method according to claim 2, further comprising repeatedly performing the first step (S1) to the fifth step (S5) with the updated first urea metered injection quantity M _25ini.

4. The calibration method according to claim 1, wherein the first step (S1) comprises:

A first sub-step (S11) of determining a first factor (F1) by means of a first sub-calibration factor table or curve based on a soot level L _S within the DPF (48) and an exhaust temperature T _48UP upstream of the DPF (48);

A second substep (S12) of determining a second factor (F2) by means of a first sub-calibration factor table or curve based on the concentration ratio R _NO2/Soot of the soot and the exhaust temperature T _48UP upstream of the DPF (48), and

And a third sub-step (S13) of multiplying the first factor (F1) by the second factor (F2) to obtain the calibration factor (F).

5. The calibration method according to claim 4, wherein the first factor (F1) and the second factor (F2) are both in the range of 0-1, inclusive of both 0 and 1, and the calibration factor (F) is a value not less than 0 and not more than 1.

6. The calibration method according to any one of claims 1-5, wherein the first urea calibration injection quantity M _25cor is obtained by multiplying the calibration factor (F) with the first urea dosing injection quantity M _25ini.

7. Calibration method according to any of claims 1-5, wherein the first urea metered injection quantity M _25ini is determined at least on the basis of the NO _X content N _20UP in the exhaust gas upstream of the close-coupled aftertreatment system (20), the temperature T _24UP of the exhaust gas upstream of the first SCR (24), the quantity of exhaust gas (FL) emitted from the engine of the engine vehicle.

8. The calibration method of any of claims 1-5, wherein the close-coupled aftertreatment system (20) and the subsurface aftertreatment system (40) further comprise a first DOC (22) and a second DOC (42) upstream of the first SCR (24) and second SCR (44), respectively.

9. A calibration module, comprising:

processor, and

A memory storing executable instructions that when executed cause the processor to perform the calibration method of any one of claims 1 to 8.

10. The calibration module of claim 9, wherein the calibration module is integrated within or communicatively connected to an electronic control unit of a vehicle.

11. A readable storage medium having stored thereon executable instructions that when executed cause a machine to perform the calibration method of any of claims 1 to 8.