Air spring debugging method and device and computer readable storage medium

Abstract

The present application relates to the technical field of spring debugging, and particularly provides an air spring debugging method, device and computer readable storage medium, aiming at solving the technical problem of poor stiffness debugging result caused by limited adjustable range of air spring stiffness. To this end, according to the method of the present application, the piston radius curve can be obtained by curve fitting of multiple radius setting values, and multiple radius sampling values of the piston can be obtained by curve sampling of the piston radius curve, and then the actual air volume when the radius of the piston changes to each radius sampling value respectively can be determined according to the initial air volume of the air spring when the spring stroke is zero, the spring stiffness simulation calculation is performed according to the radius sampling value and the actual air volume, and the stiffness debugging result is obtained. By increasing the adjustable parameters of the air spring and the debugging range of the piston radius, not only the adjustable range of the air spring stiffness can be significantly improved, but also the accurate stiffness accuracy can be obtained.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of spring debugging, in particular to an air spring debugging method, device and computer readable storage medium. BACKGROUND

[0002] As a kind of adjustable nonlinear stiffness vibration isolation element, air spring has been widely used in vehicle suspension to improve the ride comfort of vehicle. Before mass production of vehicle, air spring stiffness needs to be adjusted. The conventional air spring stiffness adjustment method is mainly to preset multiple piston radii of air spring for different air springs (different spring parameters such as structure / size), calculate the corresponding piston cross-sectional area according to the piston radius, and then calculate the air spring stiffness corresponding to each piston cross-sectional area respectively, and then compare the air spring stiffness with the preset target stiffness (the stiffness that can make the vehicle have higher ride comfort) to determine the structure / size and other spring parameters that can make the vehicle have higher ride comfort. However, since this method only considers the influence of piston cross-sectional area on air spring stiffness, the adjustable range of air spring stiffness is greatly reduced, so that the structure / size and other spring parameters that can optimally improve the ride comfort of vehicle cannot be effectively determined. SUMMARY

[0003] In order to overcome the above defects, the present application is proposed to provide an air spring debugging method, device and computer readable storage medium to solve or at least partially solve the technical problem of limited adjustable range of air spring stiffness, resulting in poor stiffness debugging result.

[0004] In a first aspect, an air spring debugging method is provided, and the method comprises:

[0005] parsing the received stiffness debugging instruction to obtain multiple radius setting values of a piston in the air spring at a vehicle body height of a vehicle equipped with the air spring specified in the stiffness debugging instruction and an initial air volume of the air spring when the piston stroke is zero;

[0006] curve fitting the radius setting values to obtain a piston radius curve and curve sampling the piston radius curve to obtain multiple radius sampling values of the piston;

[0007] determining actual air volumes when the radius of the piston changes to each radius sampling value during air spring deformation according to the initial air volume, and performing spring stiffness simulation calculation on the air spring according to the radius sampling value and the corresponding actual air volume to obtain the spring stiffness of the air spring when the radius of the piston changes to each radius sampling value;

[0008] generate a stiffness tuning result of the air spring according to the spring stiffness.

[0009] In one of the technical solutions of the air spring tuning method, the spring stroke includes a compression stroke and a stretching stroke, and the step of performing curve fitting on the radius setting values to obtain a piston radius curve specifically includes:

[0010] According to the change sequence of the radius setting values in the change process from the stretching stroke to the compression stroke, the radius setting values are divided into a plurality of radius groups, wherein each radius group includes a plurality of radius setting values, and the last radius setting value of a previous radius group and the first radius setting value of a next radius group in adjacent two radius groups are the same.

[0011] For each radius group, the radius setting values in the radius group are respectively curve fitted to obtain a radius curve corresponding to each radius group.

[0012] The radius curves are curve spliced to obtain the piston radius curve.

[0013] In one of the technical solutions of the air spring tuning method, the step of generating a stiffness tuning result of the air spring according to the spring stiffness specifically includes:

[0014] The radius sampling values and the corresponding spring stiffnesses are curve fitted to obtain a spring stiffness curve with the radius sampling values as the horizontal coordinates and the spring stiffnesses as the vertical coordinates.

[0015] The target stiffness corresponding to each radius sampling value is obtained, and the radius sampling values and the corresponding target stiffnesses are curve fitted to obtain a target stiffness curve with the radius sampling values as the horizontal coordinates and the target stiffnesses as the vertical coordinates.

[0016] The visual stiffness tuning result is generated according to the spring stiffness curve, the target stiffness curve and the piston radius curve.

[0017] In one of the technical solutions of the air spring tuning method, the step of performing curve sampling on the piston radius curve specifically includes:

[0018] The piston radius curve is curve sampled according to a preset curve value sampling interval to obtain a plurality of curve values of the piston radius curve.

[0019] The radius sampling values of the piston are determined according to the curve values.

[0020] In one of the technical solutions of the air spring tuning method, the air spring includes a bladder wrapped on at least a part of the outer surface of the piston, and the method further includes:

[0021] obtaining actual air volume of the air spring, actual radius value of the bladder and spring stiffness of the air spring when each of the radius sampling values changes to the radius of the piston during the deformation of the air spring;

[0022] displaying the actual air volume, the actual radius value of the bladder and the spring stiffness of the air spring through the visual interface, and / or, in response to the received data output instruction, generating a chart file of debugging process data by using a chart application and according to the actual air volume, the actual radius value of the bladder and the spring stiffness of the air spring.

[0023] In a second aspect, an air spring debugging device is provided, and the device comprises:

[0024] a stiffness debugging instruction analysis module configured to analyze the received stiffness debugging instruction to obtain a plurality of radius setting values of a piston in the air spring at a body height of a vehicle equipped with the air spring specified by the stiffness debugging instruction and an initial air volume of the air spring when a spring stroke is zero;

[0025] a piston radius obtaining module configured to perform curve fitting on the radius setting values to obtain a piston radius curve and perform curve sampling on the piston radius curve to obtain a plurality of radius sampling values of the piston;

[0026] a spring stiffness simulation calculation module configured to determine actual air volume when each of the radius sampling values changes to the radius of the piston during the deformation of the air spring according to the initial air volume, and perform spring stiffness simulation calculation on the air spring according to the radius sampling values and the corresponding actual air volume to obtain spring stiffness of the air spring when each of the radius sampling values changes to the radius of the piston;

[0027] a stiffness debugging result generation module configured to generate a stiffness debugging result of the air spring according to the spring stiffness.

[0028] In one technical solution of the above air spring debugging device, the spring stroke comprises a compression stroke and a stretching stroke, and the piston radius obtaining module comprises:

[0029] a radius setting value division sub-module configured to divide the radius setting values into a plurality of radius groups according to a change sequence of the radius setting values in a change process from the stretching stroke to the compression stroke, wherein each of the radius groups comprises a plurality of radius setting values and a last radius setting value of a former radius group and a first radius setting value of a latter radius group are the same in two adjacent radius groups;

[0030] a radius curve fitting sub-module configured to perform curve fitting on the radius set values in each of the radius sets respectively to obtain a radius curve corresponding to each of the radius sets respectively;

[0031] a piston radius curve obtaining sub-module configured to perform curve splicing on the radius curves to obtain the piston radius curve.

[0032] In one of the technical solutions of the air spring debugging device, the stiffness debugging result generation module comprises:

[0033] a spring stiffness curve fitting sub-module configured to perform curve fitting on the radius sample values and corresponding spring stiffnesses to obtain a spring stiffness curve, with the radius sample values as the horizontal coordinates and the spring stiffnesses as the vertical coordinates;

[0034] a target stiffness curve fitting sub-module configured to obtain a target stiffness corresponding to each of the radius sample values, and perform curve fitting on the radius sample values and corresponding target stiffnesses to obtain a target stiffness curve, with the radius sample values as the horizontal coordinates and the target stiffnesses as the vertical coordinates;

[0035] a stiffness debugging result generation sub-module configured to generate a visual stiffness debugging result according to the spring stiffness curve, the target stiffness curve and the piston radius curve.

[0036] In one of the technical solutions of the air spring debugging device, the piston radius obtaining module comprises:

[0037] a curve sampling sub-module configured to perform curve sampling on the piston radius curve according to a preset curve value sampling interval to obtain a plurality of curve values of the piston radius curve;

[0038] a radius sample value determining sub-module configured to determine the radius sample values of the piston according to the curve values.

[0039] In one of the technical solutions of the air spring debugging device, the air spring comprises a bladder wrapped around at least a part of the outer surface of the piston, and the device further comprises a debugging process data processing module, wherein the debugging process data processing module comprises a debugging process data obtaining sub-module and a debugging process data processing sub-module, and the debugging process data processing sub-module comprises a first data processing unit and / or a second data processing unit;

[0040] The debugging process data obtaining sub-module is configured to obtain the actual air volume of the air spring, the actual radius value of the bladder and the spring stiffness of the air spring when the radius of the piston changes to each of the radius sample values respectively during the deformation of the air spring.

[0041] The first data processing unit is configured to display the actual air volume, the actual radius value of the bladder and the spring stiffness of the air spring through a visualization interface;

[0042] The second data processing unit is configured to generate a chart file of the debugging process data according to the actual air volume, the actual radius value of the bladder and the spring stiffness of the air spring by using a chart application in response to the received data output instruction.

[0043] In a third aspect, a control device is provided, which includes a processor and a storage device, the storage device being adapted to store a plurality of program codes, the program codes being adapted to be loaded and run by the processor to execute the air spring debugging method of any one of the technical solutions of the air spring debugging method described above.

[0044] In a fourth aspect, a computer-readable storage medium is provided, which has a plurality of program codes stored therein, the program codes being adapted to be loaded and run by a processor to execute the air spring debugging method of any one of the technical solutions of the air spring debugging method described above.

[0045] Scheme 1, an air spring debugging method, characterized in that the method comprises:

[0046] parsing the received stiffness debugging instruction to obtain a plurality of radius setting values of a piston in the air spring at a body height of a vehicle equipped with the air spring specified in the stiffness debugging instruction and an initial air volume of the air spring when the spring stroke is zero;

[0047] curve fitting the radius setting values to obtain a piston radius curve and curve sampling the piston radius curve to obtain a plurality of radius sampling values of the piston;

[0048] determining actual air volumes when the radius of the piston changes to each of the radius sampling values respectively during air spring deformation according to the initial air volume, and performing spring stiffness simulation calculation on the air spring according to the radius sampling values and the corresponding actual air volumes to obtain spring stiffness of the air spring when the radius of the piston changes to each of the radius sampling values respectively;

[0049] generating a stiffness debugging result of the air spring according to the spring stiffness.

[0050] Scheme 2, the air spring debugging method according to scheme 1, characterized in that the spring stroke includes a compression stroke and a stretching stroke, and the step of "curve fitting the radius setting values to obtain a piston radius curve" specifically comprises:

[0051] According to a change sequence of the radius setting values from the stretching stroke to the compression stroke, the radius setting values are divided into a plurality of radius groups, wherein each of the radius groups respectively comprises a plurality of radius setting values, and a last radius setting value of a former radius group and a first radius setting value of a latter radius group in adjacent two radius groups are the same;

[0052] For each of the radius groups, the radius setting values in the radius group are respectively curve-fitted to obtain a radius curve corresponding to each of the radius groups;

[0053] The radius curves are curve-spliced to obtain the piston radius curve.

[0054] Scheme 3, the air spring debugging method according to scheme 1, characterized in that, the step of "generating the stiffness debugging result of the air spring according to the spring stiffness" specifically comprises:

[0055] The radius sampling values and the corresponding spring stiffnesses are curve-fitted to obtain a spring stiffness curve with the radius sampling values as the horizontal coordinates and the spring stiffnesses as the vertical coordinates;

[0056] The target stiffness corresponding to each of the radius sampling values is obtained, and the radius sampling values and the corresponding target stiffnesses are curve-fitted to obtain a target stiffness curve with the radius sampling values as the horizontal coordinates and the target stiffnesses as the vertical coordinates;

[0057] The visual stiffness debugging result is generated according to the spring stiffness curve, the target stiffness curve and the piston radius curve.

[0058] Scheme 4, the air spring debugging method according to scheme 1, characterized in that, the step of "curve sampling the piston radius curve" specifically comprises:

[0059] The piston radius curve is curve-sampled according to a preset curve value sampling interval to obtain a plurality of curve values of the piston radius curve;

[0060] The radius sampling values of the piston are determined according to the curve values.

[0061] Scheme 5, the air spring debugging method according to any one of schemes 1 to 4, characterized in that, the air spring comprises a bladder wrapped on at least a part of an area of the outer surface of the piston, and the method further comprises:

[0062] The actual air volume of the air spring, the actual radius value of the bladder and the spring stiffness of the air spring when the radius of the piston changes to each of the radius sampling values during the deformation of the air spring are obtained;

[0063] The actual air volume, the actual radius value of the bladder and the spring stiffness of the air spring are displayed through a visual interface, and / or a chart application is adopted and a chart file of debugging process data is generated according to the actual air volume, the actual radius value of the bladder and the spring stiffness of the air spring in response to the received data output instruction.

[0064] Scheme 6, an air spring debugging device, characterized in that the device comprises:

[0065] A stiffness debugging instruction analysis module configured to analyze the received stiffness debugging instruction to obtain a plurality of radius setting values of a piston in the air spring at a body height of a vehicle equipped with the air spring specified in the stiffness debugging instruction and an initial air volume of the air spring when a spring stroke is zero;

[0066] A piston radius acquisition module configured to perform curve fitting on the radius setting values to obtain a piston radius curve and perform curve sampling on the piston radius curve to obtain a plurality of radius sampling values of the piston;

[0067] A spring stiffness simulation calculation module configured to determine actual air volumes when the radius of the piston changes to each of the radius sampling values during air spring deformation according to the initial air volume, and perform spring stiffness simulation calculation on the air spring according to the radius sampling values and the corresponding actual air volumes to obtain spring stiffnesses of the air spring when the radius of the piston changes to each of the radius sampling values;

[0068] A stiffness debugging result generation module configured to generate a stiffness debugging result of the air spring according to the spring stiffnesses.

[0069] Scheme 7, the air spring debugging device according to scheme 6, characterized in that the spring stroke comprises a compression stroke and a stretching stroke, and the piston radius acquisition module comprises:

[0070] A radius setting value division sub-module configured to divide the radius setting values into a plurality of radius groups according to a change sequence of the radius setting values in a change process from the stretching stroke to the compression stroke, wherein each of the radius groups comprises a plurality of radius setting values and a last radius setting value of a former radius group and a first radius setting value of a latter radius group are the same in adjacent two radius groups;

[0071] A radius curve fitting sub-module configured to perform curve fitting on the radius setting values in each of the radius groups to obtain a respective radius curve corresponding to each of the radius groups;

[0072] a piston radius curve acquisition submodule configured to perform curve splicing on the radius curve to obtain the piston radius curve.

[0073] Scheme 8, the air spring debugging device according to scheme 6, characterized in that the stiffness debugging result generation module comprises:

[0074] a spring stiffness curve fitting submodule configured to perform curve fitting on the radius sample value and the corresponding spring stiffness to obtain a spring stiffness curve, with the radius sample value as the horizontal coordinate and the spring stiffness as the vertical coordinate;

[0075] a target stiffness curve fitting submodule configured to obtain a target stiffness corresponding to each radius sample value, and perform curve fitting on the radius sample value and the corresponding target stiffness to obtain a target stiffness curve, with the radius sample value as the horizontal coordinate and the target stiffness as the vertical coordinate;

[0076] a stiffness debugging result generation submodule configured to generate a visual stiffness debugging result according to the spring stiffness curve, the target stiffness curve and the piston radius curve.

[0077] Scheme 9, the air spring debugging device according to scheme 1, characterized in that the piston radius acquisition module comprises:

[0078] a curve sampling submodule configured to perform curve sampling on the piston radius curve according to a preset curve value sampling interval to obtain a plurality of curve values of the piston radius curve;

[0079] a radius sample value determination submodule configured to determine the radius sample value of the piston according to the curve values.

[0080] Scheme 10, the air spring debugging device according to any one of schemes 7 to 9, characterized in that the air spring comprises a bladder wrapped around at least a part of the outer surface of the piston, and the device further comprises a debugging process data processing module, the debugging process data processing module comprising a debugging process data acquisition submodule and a debugging process data processing submodule, the debugging process data processing submodule comprising a first data processing unit and / or a second data processing unit;

[0081] the debugging process data acquisition submodule is configured to acquire the actual air volume of the air spring, the actual radius value of the bladder and the spring stiffness of the air spring when the radius of the piston changes to each radius sample value during the deformation of the air spring;

[0082] the first data processing unit is configured to display the actual air volume, the actual radius value of the bladder and the spring stiffness of the air spring through a visual interface;

[0083] The second data processing unit is configured to generate a chart file of the debugging process data by using a chart application and according to the actual air volume, the actual value of the radius of the bladder and the spring stiffness of the air spring in response to the received data output instruction.

[0084] Scheme 11, a control device comprising a processor and a storage device, the storage device is suitable for storing a plurality of program codes, characterized in that the program codes are suitable for being loaded and run by the processor to execute the air spring debugging method of any one of schemes 1 to 5.

[0085] Scheme 12, a computer readable storage medium, wherein a plurality of program codes are stored, characterized in that the program codes are suitable for being loaded and run by a processor to execute the air spring debugging method of any one of schemes 1 to 5.

[0086] The above one or more technical solutions of the present application have at least one or more of the following beneficial effects:

[0087] In the technical scheme of the present application, the air spring debugging method can first obtain a plurality of radius setting values of the piston in the air spring and an initial air volume of the air spring when the spring stroke is zero by analyzing the stiffness debugging instruction, then curve fitting is performed on the radius setting values to obtain a piston radius curve and curve sampling is performed on the piston radius curve to obtain a plurality of radius sampling values of the piston, then the actual air volume when the radius of the piston changes to each radius sampling value during the air spring deformation process is determined according to the initial air volume, and finally the spring stiffness simulation calculation of the air spring is performed according to each radius sampling value and the actual air volume corresponding to each radius sampling value, so as to obtain the spring stiffness of the air spring when the radius of the piston changes to each radius sampling value during the air spring deformation process, and finally the stiffness debugging result of the air spring is generated according to the spring stiffness.

[0088] Based on the above embodiment, the air spring stiffness debugging method according to the embodiment of the present application not only considers the influence of the cross-sectional area (determined according to the radius sampling value of the piston) of the piston on the air spring stiffness, but also considers the influence of the initial air volume of the air spring when the spring stroke is zero on the air spring stiffness. In the debugging process of the air spring stiffness, the cross-sectional area and / or the initial air volume of the piston can be selectively adjusted, so as to obtain a more accurate stiffness debugging result of the air spring. Further, the piston radius curve is obtained by curve fitting of a plurality of discrete radius setting values, a large number of radius sampling values with small interval can be obtained by curve sampling of the piston radius curve, the debugging range of the piston cross-sectional area is improved, and then when the air spring is debugged by using the radius sampling values, the debugging range of the stiffness can be improved by improving the debugging range of the piston cross-sectional area, and the accurate stiffness precision can be obtained. BRIEF DESCRIPTION OF DRAWINGS

[0089] The disclosure of the present application will become more apparent from the following description in conjunction with the accompanying drawings. It is readily understood by those skilled in the art that the drawings are merely for the purpose of illustration and are not intended to limit the scope of protection of the present application. In which:

[0090] Figure 1 is a main step flow diagram of an air spring debugging method according to an embodiment of the present application;

[0091] Figure 2 is a main step flow diagram of a piston radius curve acquisition method according to an embodiment of the present application;

[0092] Figure 3 is a main structure block diagram of an air spring debugging device according to an embodiment of the present application.

[0093] List of reference signs:

[0094] 11: stiffness debugging instruction analysis module; 12: piston radius acquisition module; 13: spring stiffness simulation calculation module; 14: stiffness debugging result generation module. DETAILED DESCRIPTION

[0095] Some embodiments of the present application will be described below with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are only used to explain the technical principles of the present application, and are not intended to limit the scope of protection of the present application.

[0096] In the description of the present application, "module" and "processor" can include hardware, software or a combination of both. A module can include hardware circuitry, various suitable sensors, communication ports, memory, and can also include a software portion such as program code, and can be a combination of software and hardware. The processor can be a central processing unit, a microprocessor, a digital signal processor or any other suitable processor. The processor has data and / or signal processing functions. The processor can be implemented in software, hardware or a combination of both. The non-transitory computer readable storage medium includes any suitable medium that can store program code, such as a magnetic disk, a hard disk, an optical disk, a flash memory, a read-only memory, a random access memory, etc. The term "A and / or B" means all possible combinations of A and B, such as only A, only B, or both A and B. The term "at least one of A or B" or "at least one of A and B" has a similar meaning as "A and / or B", and can include only A, only B, or both A and B. The singular form of the term "one", "this" can also include the plural form.

[0097] Some terms related to the present application are explained first.

[0098] The air spring mainly realizes its elastic performance through compression and expansion of air. In the embodiment of the present application, the air spring can include a piston and a bladder wrapped around at least a part of the outer surface of the piston. The compression and expansion of air in the bladder (the extension and contraction process of the air spring) can be realized through the movement of the piston, so that the air spring has elastic performance. The radius (cross-sectional area) of the piston is also dynamically changing during the extension and contraction process of the air spring, and different elastic strokes (different compression strokes and different stretching strokes) correspond to different radii (cross-sectional areas) of the piston.

[0099] Referring to the accompanying drawings Figure 1 , Figure 1 is a schematic diagram of the main steps of the air spring debugging method according to an embodiment of the present application. As Figure 1 shown, the air spring debugging method in the embodiment of the present application mainly includes the following steps S101-S104.

[0100] Step S101: Analyzing the received stiffness debugging instruction to obtain a plurality of radius setting values of the piston in the air spring at the body height of the vehicle equipped with the air spring specified in the stiffness debugging instruction and the initial air volume of the air spring when the elastic stroke is zero.

[0101] The rigidity adjustment instruction can include multiple radius setting values of the piston in the air spring at one vehicle body height and the initial air volume of the air spring when the spring stroke is zero, or include multiple radius setting values of the piston in the air spring at multiple different vehicle body heights and the initial air volume of the air spring at each vehicle body height. When the rigidity adjustment instruction includes the radius setting values and the initial air volume corresponding to multiple vehicle body heights, the steps S102-S104 can be performed for each vehicle body height to obtain the rigidity adjustment result corresponding to each vehicle body height.

[0102] Step S102: curve fitting is performed on the radius setting values to obtain a piston radius curve, and curve sampling is performed on the piston radius curve to obtain multiple radius sampling values of the piston.

[0103] In the embodiment, the number of the radius sampling values is much larger than the number of the radius setting values, where "much larger" can mean that the difference between the number of the radius sampling values and the number of the radius setting values is greater than or equal to a preset difference threshold.

[0104] Step S103: the actual air volume when the radius of the piston changes to each radius sampling value during the deformation of the air spring is determined according to the initial air volume, and spring rigidity simulation calculation is performed on the air spring according to the radius sampling value and the corresponding actual air volume to obtain the spring rigidity of the air spring when the radius of the piston changes to each radius sampling value during the deformation of the air spring.

[0105] In the embodiment, a conventional spring rigidity calculation method can be used to perform the spring rigidity simulation calculation according to the air volume (the initial air volume and the actual air volume) and the radius sampling value. In one embodiment, the cross-sectional area of the piston corresponding to each radius sampling value can be calculated first, and then the spring rigidity simulation calculation is performed according to the cross-sectional area of the piston and using the spring rigidity calculation method shown in the following formula (1):

[0106]

[0107] The meanings of the parameters in formula (1) are as follows:

[0108] K S represents the spring rigidity of the air spring when the spring stroke is S, V0 represents the initial air volume of the air spring when the spring stroke is zero, V S represents the actual air volume of the air spring when the spring stroke is S, P0 represents the pressure in the air spring under static load, P a represents the standard atmospheric pressure, t represents a preset air dynamics index, A serepresents the cross-sectional area of the piston when the spring stroke is S. It should be noted that in the present embodiment, the air volume determination method commonly used in the technical field of air springs can be adopted to determine the actual air volume when the radius of the piston changes to each radius sampling value during the deformation of the air spring according to the initial air volume. For the sake of brevity of description, the specific method flow of the air volume determination method will not be described here.

[0109] Step S104: generating the stiffness debugging result of the air spring according to the spring stiffness.

[0110] Based on the above steps S101-S104, it can be seen that the air spring stiffness debugging method according to the embodiment of the present application not only considers the influence of the cross-sectional area of the piston (determined according to the radius sampling value of the piston) on the stiffness of the air spring, but also considers the influence of the initial air volume of the air spring when the stroke of the piston is zero on the stiffness of the air spring. In the debugging process of the stiffness of the air spring, the cross-sectional area of the piston and / or the initial air volume can be selectively adjusted, so as to obtain a more accurate stiffness debugging result of the air spring. Further, when the cross-sectional area of the piston is used to debug the stiffness of the air spring, if a plurality of cross-sectional areas with large area value intervals are adopted, the stiffness value intervals of the spring stiffness obtained by using these cross-sectional areas will also be large, so that the accurate stiffness precision of the air spring cannot be determined according to these spring stiffnesses. For this purpose, the present embodiment obtains the piston radius curve by curve fitting a plurality of discrete radius setting values, and a large number of radius sampling values with small radius value intervals can be obtained by curve sampling the piston radius curve, which improves the debugging range of the cross-sectional area of the piston, and further improves the debugging range of the stiffness by improving the debugging range of the cross-sectional area of the piston when the air spring is debugged by using these radius sampling values, and also obtains accurate stiffness precision.

[0111] The above steps S102 and S104 will be described in detail respectively.

[0112] Referring to the accompanying drawings Figure 2 In one embodiment of the above step S102, the piston radius curve can be obtained by curve fitting the radius setting values through the following steps S201-S203.

[0113] Step S201: dividing the radius setting values into a plurality of radius groups according to the change sequence of the radius setting values during the change process of the air spring from the extension stroke to the compression stroke.

[0114] In the embodiment, each radius group can include a plurality of radius setting values, and the last radius setting value of a former radius group is the same as the first radius setting value of a latter radius group in two adjacent radius groups. For example, assuming that the sequence of radius setting values is a, b, c, d, e, f, g, h, i, j, k, 1, m after the 13 radius setting values are sorted according to the sequence of change of radius setting values in the change process from the stretching stroke to the compression stroke. According to the sorting result, the radius setting values can be divided into six radius groups, which are (a, b, c), (c, d, e), (e, f, g), (g, h, i), (i, j, k), (k, 1, m) in sequence. In each two adjacent radius groups, the last radius setting value of a former radius group is the same as the first radius setting value of a latter radius group, such as the last radius setting value of (a, b, c) and the first radius setting value of (c, d, e) are both radius setting value c.

[0115] Further, in the embodiment, the compression stroke can be set as a positive spring stroke and the stretching stroke can be set as a negative spring stroke, that is, the radius value of the piston is a positive value in the compression stroke and is a negative value in the stretching stroke. When the radius setting values are sorted according to the sequence of change of radius setting values in the change process from the stretching stroke to the compression stroke, the radius setting values can also be sorted according to the sequence of change from negative to positive. In an example, the sorting result of the 13 radius setting values according to the sequence of change from negative to positive can be shown in Table 1.

[0116] Table 1

[0117] Radius setting value number Horizontal coordinate (x) of radius setting value Vertical coordinate (x) of radius setting value 1 -30 45 2 -20 45.1 3 -15 45.2 4 -10 45.3 5 -5 45.4 6 0 45.5 7 5 45.6 8 10 45.7 9 15 45.8 10 20 45.9 11 25 46 12 30 46.1 13 35 46.2

[0118] According to the sorting result shown in Table 1, the radius setting values can be divided into six radius groups, which are (1, 2, 3), (3, 4, 5), (5, 6, 7), (7, 8, 9), (9, 10, 11), (11, 12, 13) in sequence.

[0119] Step S202: for each radius group, curve fitting is performed on the radius setting values in the radius group respectively to obtain the radius curve corresponding to each radius group respectively.

[0120] Continuing to refer to the example in step S201, for the radius group (a, b, c), curve fitting can be performed on the radius setting values abc to obtain the radius curve of the radius group (a, b, c). For the radius group (c, d, e), curve fitting can be performed on the radius setting values cde to obtain the radius curve of the radius group (c, d, e).

[0121] It should be noted that the radius setting values can be subjected to curve fitting to obtain corresponding radius curves by using a curve fitting method in the field of data processing in this embodiment. For the sake of brevity, the curve fitting method will not be described herein.

[0122] Step S203: curve splicing is performed on the radius curves to obtain the piston radius curve.

[0123] Since the last radius setting value of the former radius group and the first radius setting value of the latter radius group in the adjacent two radius groups are the same, the radius curves corresponding to the adjacent two radius groups have the same curve point, and the two radius curves can be spliced into a smooth curve through the curve point. With reference to the example in step S202, the radius curves of the six radius groups can be spliced into a complete smooth curve through curve splicing, and the complete smooth curve can be taken as the piston radius curve.

[0124] Based on the embodiments described in steps S201-S203, the piston radius curve is subjected to segmented fitting by dividing the radius setting values into multiple radius groups and performing curve fitting on each radius group, which can significantly improve the fitting efficiency and accuracy of the piston radius curve compared with directly performing curve fitting on all the radius setting values.

[0125] Further, in another embodiment of step S102, the piston radius curve can be subjected to curve sampling through steps S204-S205.

[0126] Step S204: the piston radius curve is subjected to curve sampling according to a preset curve value sampling interval to obtain multiple curve values of the piston radius curve.

[0127] Step S205: the radius sampling values of the piston are determined according to the curve values.

[0128] Based on the above embodiments, multiple equally spaced curve values can be sampled from the piston radius curve. After the cross-sectional areas of the piston are calculated by taking these curve values as the radius sampling values, the cross-sectional areas can represent the uniform change of the cross-sectional areas of the piston in the extension and contraction process of the air spring, so that the spring stiffness adjustment using the cross-sectional areas can obtain more accurate stiffness adjustment results. In addition, in this embodiment, the preset curve value sampling interval can be set to a small value, for example, the preset curve value sampling interval is less than or equal to the preset interval threshold. After the piston radius curve is subjected to curve sampling according to the preset curve value sampling interval, a large number of radius sampling values with small radius value intervals can be obtained, which can improve the adjustment range of the cross-sectional areas of the piston, and further improve the adjustment range of the stiffness, and also obtain accurate stiffness accuracy.

[0129] In one embodiment of the step S104, the stiffness tuning result of the air spring can be generated by the following steps 11-13 according to the spring stiffness.

[0130] Step 11: curve fitting the radius sampling values and the corresponding spring stiffnesses to obtain a spring stiffness curve with the radius sampling values as the horizontal coordinates and the spring stiffnesses as the vertical coordinates.

[0131] It should be noted that in the present embodiment, the spring stiffness curve can be obtained by curve fitting the radius sampling values and the spring stiffnesses using a conventional curve fitting method in the field of data processing, and the curve fitting method will not be described herein for the sake of brevity.

[0132] Step 12: obtaining the target stiffnesses corresponding to each radius sampling value, and curve fitting the radius sampling values and the corresponding target stiffnesses to obtain a target stiffness curve with the radius sampling values as the horizontal coordinates and the target stiffnesses as the vertical coordinates.

[0133] In the present embodiment, the target stiffnesses corresponding to the different piston cross-sectional areas during the extension and retraction of the air spring can be determined according to the stiffness requirement of the air spring (e.g., the stiffness required for the vehicle to have higher ride comfort), and then the target stiffness corresponding to each radius sampling value can be set according to the determined target stiffnesses. In addition, in the present embodiment, the target stiffness curve can also be obtained by curve fitting the radius sampling values and the target stiffnesses using a conventional curve fitting method in the field of data processing, and the curve fitting method will not be described herein for the sake of brevity.

[0134] Step 13: generating the visualized stiffness tuning result according to the spring stiffness curve, the target stiffness curve, and the piston radius curve.

[0135] Since the horizontal coordinates of the spring stiffness curve and the target stiffness curve are the same, the spring stiffness curve and the target stiffness curve can be displayed on the same curve graph to compare the spring stiffness and the target stiffness corresponding to the same radius sampling value.

[0136] Further, based on the aforementioned step S101, the radius setting values of the pistons in the air spring at the specified vehicle body height and the initial air volume of the air spring when the piston stroke is zero can be obtained by analyzing the stiffness tuning instruction, and thus the stiffness tuning results corresponding to different vehicle body heights can be obtained by the steps S101-S103, and the visualized stiffness tuning results corresponding to different vehicle body heights can be displayed in the same visual interface to compare the visualized stiffness tuning results of the same vehicle at different vehicle body heights when generating the visualized stiffness tuning result.

[0137] Further, in another embodiment of the air spring stiffness method according to the present application, the air spring stiffness debugging method can comprise the following steps S105-S106 of displaying the debugging process data of the spring stiffness in addition to the steps in the aforementioned method embodiments.

[0138] Step S105: obtaining the actual air volume of the air spring, the actual radius value of the bladder and the spring stiffness of the air spring when the radius of the piston changes to each radius sample value during the deformation process of the air spring. The bladder refers to the bladder wrapped around at least a part of the outer surface of the piston in the air spring.

[0139] Step S106: displaying the actual air volume, the actual radius value of the bladder and the spring stiffness of the air spring through a visual interface.

[0140] In addition, in one embodiment, a chart application can be used to generate a chart file of the debugging process data of the actual air volume, the actual radius value of the bladder and the spring stiffness of the air spring in response to the received data output instruction. Those skilled in the art can flexibly select to use the chart application according to actual needs, for example, Microsoft Office Excel can be used as the chart application in the embodiment.

[0141] Through steps S105-S106, the user can conveniently obtain, view and store all the debugging process data in the stiffness debugging process.

[0142] It should be noted that although the steps are described in a specific order in the above embodiments, those skilled in the art can understand that, in order to achieve the effect of the present application, the different steps do not necessarily have to be executed in such an order, they can be executed simultaneously (in parallel) or in other orders, and these changes are within the protection scope of the present application.

[0143] Further, the present application also provides an air spring debugging device.

[0144] Referring to the accompanying drawings Figure 3 , Figure 3 is the main structure block diagram of the air spring debugging device according to one embodiment of the present application. As shown in Figure 3As shown, the air spring debugging device in the embodiment of the present application mainly comprises a stiffness debugging instruction analysis module 11, a piston radius acquisition module 12, a spring stiffness simulation calculation module 13 and a stiffness debugging result generation module 14. In some embodiments, one or more of the stiffness debugging instruction analysis module 11, the piston radius acquisition module 12, the spring stiffness simulation calculation module 13 and the stiffness debugging result generation module 14 can be combined together to become one module. In some embodiments, the stiffness debugging instruction analysis module 11 can be configured to analyze the received stiffness debugging instruction to obtain a plurality of radius setting values of the piston in the air spring at the body height of the vehicle equipped with the air spring specified in the stiffness debugging instruction and an initial air volume of the air spring when the spring stroke is zero. The piston radius acquisition module 12 can be configured to perform curve fitting on the radius setting values to obtain a piston radius curve and perform curve sampling on the piston radius curve to obtain a plurality of radius sampling values of the piston. The spring stiffness simulation calculation module 13 can be configured to determine the actual air volume when the radius of the piston changes to each radius sampling value during the deformation of the air spring according to the initial air volume, and perform spring stiffness simulation calculation on the air spring according to the radius sampling value and the corresponding actual air volume to obtain the spring stiffness of the air spring when the radius of the piston changes to each radius sampling value. The stiffness debugging result generation module 14 can be configured to generate the stiffness debugging result of the air spring according to the spring stiffness. In one embodiment, the description of the functions implemented can be referred to the steps S101-S104.

[0145] In one embodiment, the piston radius acquisition module 12 can comprise a radius setting value division sub-module, a radius curve fitting sub-module and a piston radius curve acquisition sub-module. In this embodiment, the spring stroke comprises a compression stroke and a stretching stroke, and the radius setting value division sub-module can be configured to divide the radius setting values into a plurality of radius groups according to the change sequence of the radius setting values in the change process from the stretching stroke to the compression stroke, wherein each radius group can comprise a plurality of radius setting values and the last radius setting value of the former radius group and the first radius setting value of the latter radius group in the adjacent two radius groups are the same. The radius curve fitting sub-module can be configured to perform curve fitting on the radius setting values in each radius group to obtain a radius curve corresponding to each radius group, respectively. The piston radius curve acquisition sub-module can be configured to perform curve splicing on the radius curves to obtain the piston radius curve. In one embodiment, the description of the functions implemented can be referred to the steps S201-S203.

[0146] In an embodiment, the stiffness tuning result generation module 14 can include a spring stiffness curve fitting sub-module, a target stiffness curve fitting sub-module, and a stiffness tuning result generation sub-module. In the embodiment, the spring stiffness curve fitting sub-module can be configured to perform curve fitting on the radius sampling values and the corresponding spring stiffnesses with the radius sampling values as the horizontal coordinates and the spring stiffnesses as the vertical coordinates to obtain a spring stiffness curve. The target stiffness curve fitting sub-module can be configured to obtain the target stiffnesses corresponding to each of the radius sampling values, and perform curve fitting on the radius sampling values and the corresponding target stiffnesses with the radius sampling values as the horizontal coordinates and the target stiffnesses as the vertical coordinates to obtain a target stiffness curve. The stiffness tuning result generation sub-module can be configured to generate a visualized stiffness tuning result according to the spring stiffness curve, the target stiffness curve, and the piston radius curve. In an embodiment, the description of the implementation of the functions can be referred to the description of step S104.

[0147] In an embodiment, the piston radius obtaining module 12 can include a curve sampling sub-module and a radius sampling value determining sub-module. In the embodiment, the curve sampling sub-module can be configured to perform curve sampling on the piston radius curve according to a preset curve value sampling interval to obtain a plurality of curve values of the piston radius curve. The radius sampling value determining sub-module can be configured to determine the radius sampling values of the piston according to the curve values. In an embodiment, the description of the implementation of the functions can be referred to the description of steps S204-S205.

[0148] In an embodiment, the air spring can include a bellows wrapped around at least a portion of an outer surface of the piston, Figure 3 The air spring tuning device shown can further include a tuning process data processing module. In the embodiment, the tuning process data processing module can include a tuning process data obtaining sub-module and a tuning process data processing sub-module, and the tuning process data processing sub-module can include a first data processing unit and / or a second data processing unit. Specifically, the tuning process data obtaining sub-module can be configured to obtain the actual air volume of the air spring, the actual radius value of the bellows, and the spring stiffness of the air spring when the radius of the piston changes to each of the radius sampling values during the deformation process of the air spring. The first data processing unit can be configured to display the actual air volume, the actual radius value of the bellows, and the spring stiffness of the air spring through a visual interface. The second data processing unit can be configured to, in response to a received data output instruction, generate a chart file of the tuning process data by using a chart application and according to the actual air volume, the actual radius value of the bellows, and the spring stiffness of the air spring. In an embodiment, the description of the implementation of the functions can be referred to the description of steps S105-S106.

[0149] The air spring tuning device described above is configured to perform Figures 1-2The technical principles, technical problems solved and technical effects of the two embodiments of the air spring debugging method are similar. The technical personnel in the field can clearly understand that, for the convenience and brevity of description, the specific working process and related description of the air spring debugging device can refer to the description of the embodiments of the air spring debugging method, which will not be repeated here.

[0150] Those skilled in the art can understand that all or part of the processes in the method of the above-mentioned embodiment can also be completed by a computer program instructing related hardware. The computer program can be stored in a computer readable storage medium. When the computer program is executed by a processor, the steps of the above-mentioned various method embodiments can be implemented. The computer program includes computer program code, which can be in the form of source code, object code, executable files or some intermediate forms. The computer readable medium can include any entity or device, medium, U disk, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory, random access memory, electrical carrier signal, telecommunication signal and software distribution medium, etc. that can carry the computer program code. It should be noted that the content of the computer readable medium can be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, the computer readable medium does not include electrical carrier signals and telecommunication signals.

[0151] Further, the present application also provides a control device. In an embodiment of the control device according to the present application, the control device includes a processor and a storage device. The storage device can be configured to store a program for executing the air spring debugging method of the above-mentioned method embodiments. The processor can be configured to execute the program in the storage device, which includes but is not limited to the program for executing the air spring debugging method of the above-mentioned method embodiments. For the convenience of description, only the parts related to the embodiments of the present application are shown, and the specific technical details not disclosed are referred to the method part of the embodiments of the present application. The control device can be a control device device formed by various electronic devices.

[0152] Further, the present application also provides a computer readable storage medium. In an embodiment of the computer readable storage medium according to the present application, the computer readable storage medium can be configured to store a program for executing the air spring debugging method of the above-mentioned method embodiments. The program can be loaded and run by the processor to implement the above-mentioned air spring debugging method. For the convenience of description, only the parts related to the embodiments of the present application are shown, and the specific technical details not disclosed are referred to the method part of the embodiments of the present application. The computer readable storage medium can be a storage device device formed by various electronic devices. Optionally, the computer readable storage medium in the embodiments of the present application is a non-transitory computer readable storage medium.

[0153] Further, it should be understood that, since the setting of each module is only for illustrating the functional units of the device of the present application, the corresponding physical device of the module can be the processor itself, or a part of the software in the processor, a part of the hardware, or a part of the combination of the software and the hardware. Therefore, the number of each module in the figure is only illustrative.

[0154] Those skilled in the art can understand that each module in the device can be adaptively split or combined. Such splitting or combining of the specific module does not cause the technical solution to deviate from the principles of the present application, and therefore, the technical solution after splitting or combining will fall within the protection scope of the present application.

[0155] So far, the technical solution of the present application has been described in combination with one embodiment shown in the drawings, but those skilled in the art can easily understand that the protection scope of the present application is obviously not limited to these specific embodiments. Those skilled in the art can make equivalent changes or replacements to the related technical features without deviating from the principles of the present application, and the technical solution after the changes or replacements will fall within the protection scope of the present application.

Claims

1. A method of air spring tuning, comprising: The method comprises: selectively adjusting the cross-sectional area of the piston and / or the initial air volume in the air spring during debugging, wherein the method comprises parsing the received stiffness debugging instruction to obtain a plurality of radius setting values of the piston in the air spring at a body height of a vehicle equipped with the air spring specified in the stiffness debugging instruction and an initial air volume of the air spring when the piston stroke is zero; curve fitting the radius setting values to obtain a piston radius curve and curve sampling the piston radius curve to obtain a plurality of radius sampling values of the piston, the radius sampling values being used to determine the cross-sectional area of the piston; determining actual air volumes of the air spring when the radius of the piston changes to each of the radius sampling values during air spring deformation according to the initial air volume, and performing spring stiffness simulation calculation on the air spring according to the radius sampling values and the corresponding actual air volumes to obtain the spring stiffness of the air spring when the radius of the piston changes to each of the radius sampling values; generating a stiffness debugging result of the air spring according to the spring stiffness; the generation of the stiffness debugging result of the air spring comprises: curve fitting the radius sampling values and the corresponding spring stiffness with the radius sampling values as the horizontal coordinates and the spring stiffness as the vertical coordinates to obtain a spring stiffness curve; obtaining a target stiffness corresponding to each of the radius sampling values, and curve fitting the radius sampling values and the corresponding target stiffness with the radius sampling values as the horizontal coordinates and the target stiffness as the vertical coordinates to obtain a target stiffness curve; and generating a visualized stiffness debugging result according to the spring stiffness curve, the target stiffness curve and the piston radius curve.

2. The air spring tuning method of claim 1, wherein, The piston stroke comprises a compression stroke and a stretching stroke, and the step of "curve fitting the radius setting values to obtain a piston radius curve" specifically comprises: dividing the radius setting values into a plurality of radius groups according to the change sequence of the radius setting values in the change process from the stretching stroke to the compression stroke, wherein each of the radius groups comprises a plurality of radius setting values, and the last radius setting value of a previous radius group and the first radius setting value of a subsequent radius group in adjacent two radius groups are the same; for each of the radius groups, respectively curve fitting the radius setting values in the radius group to obtain a radius curve corresponding to each of the radius groups; curve splicing the radius curves to obtain the piston radius curve.

3. The air spring tuning method of claim 1, wherein, The step of "curve sampling the piston radius curve" specifically comprises: curve sampling the piston radius curve according to a preset curve value sampling interval to obtain a plurality of curve values of the piston radius curve; determining the radius sampling values of the piston according to the curve values.

4. The air spring tuning method of any one of claims 1-3, wherein, The air spring comprises a bladder wrapped around at least a part of the outer surface of the piston, and the method further comprises: obtaining the actual air volume of the air spring, the actual radius value of the bladder and the spring stiffness of the air spring when the radius of the piston changes to each of the radius sampling values during air spring deformation; The actual air volume, the actual radius value of the bladder and the spring stiffness of the air spring are displayed through a visual interface, and / or a chart application is adopted and a chart file of debugging process data is generated according to the actual air volume, the actual radius value of the bladder and the spring stiffness of the air spring in response to the received data output instruction.

5. An air spring tuning device, characterized by, The device is configured to selectively adjust the cross-sectional area of the piston in the air spring and / or the initial air volume in the debugging process, wherein the device comprises a stiffness debugging instruction parsing module; The stiffness debugging instruction parsing module is configured to parse the received stiffness debugging instruction to obtain a plurality of radius setting values of the piston in the air spring at a body height of a vehicle equipped with the air spring specified in the stiffness debugging instruction and an initial air volume of the air spring when the spring stroke is zero; The device further comprises: a piston radius obtaining module configured to perform curve fitting on the radius setting values to obtain a piston radius curve and perform curve sampling on the piston radius curve to obtain a plurality of radius sampling values of the piston, the radius sampling values being used to determine the cross-sectional area of the piston; a spring stiffness simulation calculation module configured to determine actual air volumes when the radius of the piston changes to each of the radius sampling values in the air spring deformation process according to the initial air volume, and perform spring stiffness simulation calculation on the air spring according to the radius sampling values and the corresponding actual air volumes to obtain spring stiffnesses of the air spring when the radius of the piston changes to each of the radius sampling values; a stiffness debugging result generation module configured to generate a stiffness debugging result of the air spring according to the spring stiffnesses; The stiffness debugging result generation module comprises: a spring stiffness curve fitting sub-module configured to perform curve fitting on the radius sampling values and the corresponding spring stiffnesses to obtain a spring stiffness curve with the radius sampling values as the horizontal coordinates and the spring stiffnesses as the vertical coordinates; a target stiffness curve fitting sub-module configured to obtain a target stiffness corresponding to each of the radius sampling values, and perform curve fitting on the radius sampling values and the corresponding target stiffnesses to obtain a target stiffness curve with the radius sampling values as the horizontal coordinates and the target stiffnesses as the vertical coordinates; a stiffness debugging result generation sub-module configured to generate a visual stiffness debugging result according to the spring stiffness curve, the target stiffness curve and the piston radius curve.

6. The air spring tuning device of claim 5, wherein, The spring stroke comprises a compression stroke and a stretching stroke, and the piston radius obtaining module comprises: a radius setting value division sub-module configured to divide the radius setting values into a plurality of radius groups according to the change sequence of the radius setting values in the change process from the stretching stroke to the compression stroke, wherein each of the radius groups comprises a plurality of radius setting values and the last radius setting value of a former radius group and the first radius setting value of a latter radius group in adjacent two radius groups are the same. a radius curve fitting submodule configured to, for each of the radius groups, perform curve fitting on the radius set values in the radius group respectively to obtain a respective radius curve corresponding to each of the radius groups; a piston radius curve obtaining submodule configured to perform curve splicing on the radius curves to obtain the piston radius curve.

7. The air spring tuning device of claim 5, wherein, The piston radius obtaining module comprises: a curve sampling submodule configured to perform curve sampling on the piston radius curve according to a preset curve value sampling interval to obtain a plurality of curve values of the piston radius curve; a radius sampling value determining submodule configured to determine a radius sampling value of the piston according to the curve values.

8. The air spring tuning device of any one of claims 6-7, wherein, The air spring comprises a bladder wrapped around at least a part of the outer surface of the piston, and the device further comprises a debugging process data processing module, the debugging process data processing module comprising a debugging process data obtaining submodule and a debugging process data processing submodule, the debugging process data processing submodule comprising a first data processing unit and / or a second data processing unit; The debugging process data obtaining submodule is configured to obtain the actual air volume of the air spring, the actual radius value of the bladder and the spring stiffness of the air spring when the radius of the piston changes to each of the radius sampling values respectively during the deformation process of the air spring; The first data processing unit is configured to display the actual air volume, the actual radius value of the bladder and the spring stiffness of the air spring through a visual interface; The second data processing unit is configured to, in response to a received data output instruction, generate a chart file of debugging process data by using a chart application program and according to the actual air volume, the actual radius value of the bladder and the spring stiffness of the air spring.

9. A control device comprising a processor and a storage device, the storage device being adapted to store a plurality of program codes, characterized in that, The program code is adapted to be loaded and run by the processor to execute the air spring debugging method of any one of claims 1 to 4.

10. A computer readable storage medium having stored therein a plurality of program codes, characterized in that, The program code is adapted to be loaded and run by the processor to execute the air spring debugging method of any one of claims 1 to 4.

Images