Method for 3D printer and 3D printer

Abstract

A method for a 3D printer and a 3D printer. The 3D printer includes: a printing platform and N pressure sensors, the printing platform includes a printing plane for carrying a printed object, and the N pressure sensors are configured to generate a sensing signal indicating a force applied to the printing plane, where N is a positive integer greater than or equal to 1. The method includes: controlling the printing platform to move along the Z axis of the 3D printer according to a predetermined motion law; obtaining corresponding sensing signals output by the N pressure sensors during the movement of the printing platform; and determining the sensitivity of each of the N pressure sensors based on the acceleration signal and the corresponding sensing signal of the printing platform during the movement.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to Chinese Patent Application No. 2021116819766 filed on December 31, 2021, the contents of which are incorporated herein by reference in their entirety. Technical Field

[0003] The present disclosure relates to the technical field of 3D printing, and in particular to a method for a 3D printer, a 3D printer, a computer-readable storage medium, and a computer program product. Background Art

[0004] A 3D printer (also known as a three-dimensional printer or a stereo printer) constructs a three-dimensional object by printing layer by layer. The 3D printer includes a print head for extruding printing material and a printing platform for depositing printing material to form a three-dimensional object. The print head is configured to move relative to the printing platform and extrude printing material onto the surface of the printing platform while moving. The printing material is deposited layer by layer on the surface of the printing platform and fused together to print a three-dimensional object.

[0005] In the related art, a pressure sensor is also provided on the 3D printer, and the pressure sensor can be used to sense the pressure applied to the surface of the printing platform, so as to detect whether the printing platform is level, for example. In order to ensure the accuracy of the detection result, the pressure sensor needs to be calibrated.

[0006] However, the calibration method of the pressure sensor in the related art is complicated to operate.

[0007] The methods described in this section are not necessarily methods that have been previously conceived or employed. Unless otherwise indicated, it should not be assumed that any method described in this section is considered to be prior art simply because it is included in this section. Similarly, unless otherwise indicated, the issues mentioned in this section should not be considered to have been recognized in any prior art. Summary of the invention

[0008] Embodiments of the present disclosure provide a method for a 3D printer, a 3D printer, a computer-readable storage medium, and a computer program product.

[0009] According to one aspect of the present disclosure, a method for a 3D printer is provided, the 3D printer comprising: a printing platform and N pressure sensors, the printing platform comprising a printing plane for carrying a printed object, each of the N pressure sensors being configured to generate a sensing signal in response to a force applied to the printing platform, N being a positive integer greater than or equal to 1, the method comprising: controlling the printing platform to move along a Z-axis of the 3D printer according to a predetermined motion law; obtaining values ​​corresponding to corresponding sensing signals output by the N pressure sensors during movement of the printing platform; and determining the sensitivity of each of the N pressure sensors based on the acceleration of the printing platform during movement corresponding to the predetermined motion law and the values ​​corresponding to the corresponding sensing signals.

[0010] According to another aspect of the present disclosure, a 3D printer is provided, comprising: a printing platform, the printing platform comprising a printing plane for carrying a printed object; N pressure sensors, each of the N pressure sensors being configured to generate a sensing signal in response to a force applied to the printing platform, N being a positive integer greater than or equal to 1; and a processor, the processor being configured to execute instructions to implement the method as described above.

[0011] According to another aspect of the present disclosure, a non-transitory computer-readable storage medium storing computer instructions is provided, wherein when the computer instructions are executed by a processor of the 3D printer as described above, the 3D printer implements the method as described above.

[0012] According to another aspect of the present disclosure, a computer program product is provided, comprising a computer program, wherein when the computer program is executed by a processor of the 3D printer as described above, the computer program enables the 3D printer to implement the method as described above.

[0013] According to the method for a 3D printer, the 3D printer, the computer-readable storage medium, and the computer program product provided in the embodiments of the present disclosure, the pressure sensor can be calibrated quickly with simple operation.

[0014] It should be understood that the content described in this section is not intended to identify the key or important features of the embodiments of the present disclosure, nor is it intended to limit the scope of the present disclosure. Other features of the present disclosure will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In the accompanying drawings, unless otherwise specified, the same reference numerals throughout the multiple drawings represent the same or similar parts or elements. These drawings are not necessarily drawn to scale. It should be understood that these drawings only depict some embodiments disclosed in accordance with the present disclosure and should not be regarded as limiting the scope of the present disclosure.

[0016] Figure 1A structural diagram of a 3D printer according to an embodiment of the present disclosure is shown;

[0017] Figure 2 A flow chart of a method for a 3D printer according to an embodiment of the present disclosure is shown;

[0018] Figure 3 Shows Figure 2 A flow chart of a method for determining the sensitivity of each of N pressure sensors;

[0019] Figure 4 A flow chart of a method for a 3D printer according to an embodiment of the present disclosure is shown. DETAILED DESCRIPTION

[0020] The following is a description of exemplary embodiments of the present disclosure in conjunction with the accompanying drawings, including various details of the embodiments of the present disclosure to facilitate understanding, which should be considered as merely exemplary. Therefore, it should be recognized by those of ordinary skill in the art that various changes and modifications may be made to the embodiments described herein without departing from the scope of the present disclosure. Similarly, for the sake of clarity and conciseness, the description of well-known functions and structures is omitted in the following description.

[0021] In the present disclosure, unless otherwise specified, the use of the terms "first", "second", etc. to describe various elements is not intended to limit the positional relationship, timing relationship, or importance relationship of these elements, and such terms are only used to distinguish one element from another element. In some examples, the first element and the second element may refer to the same instance of the element, and in some cases, based on the description of the context, they may also refer to different instances.

[0022] The terms used in the description of various examples in this disclosure are only for the purpose of describing specific examples and are not intended to be limiting. Unless the context clearly indicates otherwise, if the number of elements is not specifically limited, the element can be one or more. In addition, the term "and / or" used in this disclosure covers any one of the listed items and all possible combinations.

[0023] For a 3D printer, in order to achieve leveling of the printing platform, the printing platform may be provided with at least one pressure sensor. In the automatic leveling operation of the printing platform, the print head may be controlled to move from a predetermined position toward the surface of the printing platform. When the print head contacts the printing platform, the print head applies a force to the printing platform. The force generated by the contact can be sensed by the pressure sensor and calculated from the output voltage of the pressure sensor.

[0024] Specifically, the actual pressure on the pressure sensor can be equal to the ratio of its output voltage to the sensitivity of the pressure sensor. If there is an error in the sensitivity of the pressure sensor, the pressure value calculated by the output voltage will not match the actual pressure value, which directly affects the accuracy of the test result. Therefore, the pressure sensor needs to be calibrated when it is used for the first time or during routine maintenance.

[0025] In the related art, the calibration method of the pressure sensor is to apply a known force to the pressure sensor to be tested, such as placing a weight of known weight, so as to obtain the corresponding relationship between the applied pressure and the output of the pressure sensor. However, this measurement method is relatively cumbersome, especially for users using 3D printers, the operation is particularly complicated.

[0026] In order to alleviate, mitigate or eliminate at least one of the above problems, the embodiments of the present disclosure provide a method for a 3D printer and a 3D printer, which can quickly calibrate a pressure sensor and is easy to operate. The embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings.

[0027] Figure 1 3D printer 100 according to an embodiment of the present disclosure is shown. Figure 1 , the 3D printer 100 includes: a printing platform 110 and N pressure sensors 130, the printing platform 110 includes a printing plane 112 for carrying a printed object, each of the N pressure sensors 130 can be configured to generate a sensing signal by responding to a force applied to the printing platform 110, or each of the N pressure sensors 130 can be configured to generate a sensing signal indicating a force applied to the printing plane 112, or the N pressure sensors 130 can be configured to generate a sensing signal indicating a force applied to the printing platform, and N is a positive integer greater than or equal to 1. Figure 1 In the example of FIG. 2 , two pressure sensors 130 are shown.

[0028] In addition, the 3D printer 100 further includes a print head 120 located above the printing platform 110. The print head 120 is configured to be movable relative to the printing platform 110, for example, it can move in a horizontal plane. The printing platform 110 defines a printing plane 112. The printing material extruded from the print head 120 is deposited layer by layer on the printing plane 112 defined by the printing platform 110, thereby printing a three-dimensional object.

[0029] It is understood that the number of the pressure sensor 130 may be at least one. The at least one pressure sensor 130 is mounted on the printing platform 110 and is configured to generate a sensing signal indicating a force applied to the printing plane 112 .

[0030] The pressure sensor 130 may be any type of pressure sensor capable of generating the above-mentioned sensing signal. In one example, the pressure sensor 130 is a piezoelectric ceramic sensor. The force applied to the printing plane 112 may cause the piezoelectric ceramic sensor to deform accordingly. The piezoelectric ceramic sensor is further capable of generating a sensing signal (e.g., a potential difference) indicating the force applied to the printing plane 112 based on the amount of deformation. The piezoelectric ceramic sensor has low cost and high measurement reliability. The use of a piezoelectric ceramic pressure sensor is at least conducive to reducing costs and improving reliability.

[0031] The pressure sensor 130 may be mounted to the printing platform 110 in any suitable manner as long as it can sense the force applied to the printing plane 112. In some embodiments, the pressure sensor 130 is mounted to the flexible cantilever structure 115 of the printing platform 110. The flexible cantilever structure 115 is configured to deform due to the force applied to the printing plane 112. Mounting the pressure sensor 130 via the flexible cantilever structure 115 enables the pressure sensor 130 to more sensitively and reliably sense the force applied to the printing plane 112.

[0032] The 3D printer 100 further includes a lifting mechanism 150. The lifting mechanism 150 may be connected to the flexible cantilever structure 115 and driven by a driving mechanism (eg, a motor, not shown) to achieve a vertical movement of the printing plane 112 in the Z axis ( Figure 1 Therefore, the lifting mechanism 150 can also be called a "Z pulley".

[0033] In addition, the 3D printer 100 further includes a processor (not shown) for controlling the printing operation of the 3D printer 100. The processor may be integrated into the 3D printer 100. In another embodiment, the processor may be independent of the 3D printer 100 and communicate with the 3D printer 100 by wire or wireless means. The processor may be used to control the lifting mechanism 150 by controlling the driving mechanism so that the printing plane 112 moves in the Z-axis direction. The processor may also be connected in communication with the pressure sensor 130 to obtain a sensing signal of the pressure sensor 130.

[0034] Figure 2 FIG. 2 is a flow chart showing a method 200 for a 3D printer according to an embodiment of the present disclosure. Figure 2 , the method 200 includes steps S210 to S240. For ease of description, the following will be combined with Figure 1 The method 200 is described with reference to the 3D printer 100 .

[0035] In step S210 , the printing platform 110 is controlled to move along the Z axis of the 3D printer 100 according to a predetermined motion rule.

[0036] In step S220 , an acceleration signal is determined from a predetermined motion law, the acceleration signal indicating the acceleration of the printing platform 110 during the motion.

[0037] In step S230 , corresponding sensing signals output by the N pressure sensors 130 during the movement of the printing platform 110 are acquired.

[0038] In step S240 , the sensitivity of each of the N pressure sensors 130 is determined based on the acceleration signal, the corresponding sensing signal, the mass of the printing platform 110 , and the corresponding positions of the N pressure sensors 130 relative to the center of mass of the printing platform 110 .

[0039] The movement of the printing platform 110 along the Z axis can be achieved by the movement of the lifting mechanism 150. The lifting mechanism 150 can be driven by a driving mechanism such as a motor. The processor can control the displacement of the printing platform 110 along the Z axis by controlling the output of the motor. The predetermined motion law can be a law of change of the displacement of the printing platform 110 over time.

[0040] In step S220, the acceleration signal may be a continuous signal with respect to time or a discrete sequence with respect to time. For example, in some embodiments, the law of change of acceleration with time, i.e., a continuous signal, may be obtained by the second derivative of a predetermined motion law. In other embodiments, the processor may execute a G-code, which specifies a series of position coordinates of the printing platform 110 on a predetermined motion law. By performing a second-order difference on these discrete position coordinate sequences, a discrete sequence of acceleration change with time may be obtained.

[0041] In step S230, the sensing signal may be an electrical signal output by the pressure sensor 130, such as a voltage signal or a current signal, etc. In some examples, obtaining the sensing signal may be understood as obtaining a value corresponding to the sensing signal.

[0042] It can be understood that the resultant force (i.e., inertial force) to which the printing platform 110 is subjected during the movement can be obtained through the acceleration signal. The resultant force can be considered to be applied to the center of mass position of the printing platform 110. According to the corresponding position of each pressure sensor 130 relative to the center of mass of the printing platform 110, that is, the horizontal distance of each pressure sensor 130 from the center of mass, and based on the force analysis, the actual pressure to which each pressure sensor 130 is subjected can be obtained. Taking the sensing signal as a voltage signal as an example, the sensitivity of each pressure sensor 130 can be obtained by the ratio of the sensing signal of the pressure sensor 130 to the actual pressure to which it is subjected.

[0043] In some examples, the sensitivity of each of the N pressure sensors may also be determined based solely on the acceleration of the printing platform during movement corresponding to a predetermined motion law and the value of a corresponding sensing signal, and the present disclosure is not limited in this regard.

[0044] It should be noted that, for a specific motion law, the acceleration of the corresponding printing platform during the motion may be known. In this case, method 200 may only include step S210, step S230 and step S240, and the present disclosure is not limited in this respect.

[0045] The embodiments of the present disclosure provide a method for a 3D printer, which can automatically calculate the sensitivity of a pressure sensor without the need for the user to apply weights for measurement, and the operation is simple and fast.

[0046] It will be understood that the order of step S220 and step S230 may be interchanged, or may be performed simultaneously, and the present disclosure is not limited in this regard. Figure 3 Shows Figure 2 Flow chart of a method for determining the sensitivity of each of N pressure sensors. Figure 3 In some embodiments, the method of determining the sensitivity of each of the N pressure sensors 130 in step S240 specifically includes: step S310 and step S320.

[0047] In step S310 , based on the acceleration signal, the mass of the printing platform 110 and the corresponding positions of the N pressure sensors 130 relative to the center of mass of the printing platform 110 , the corresponding reaction forces generated at the N pressure sensors 130 by the inertial force exerted on the printing platform 110 during movement are determined.

[0048] In step S320 , the sensitivity of each of the N pressure sensors 130 is determined based on the corresponding reaction force and the corresponding sensing signal.

[0049] Return to reference Figure 1 When calibrating the pressure sensors 130, the printing platform 110 moves along a predetermined motion pattern without load. Since inertial force is generated during the motion, the inertial force can be sensed by each pressure sensor 130. For example, the printing platform 110 is provided with two pressure sensors 130. Figure 1 The pressure sensor 130 on the left is the first sensor, and the pressure sensor 130 on the right is the second sensor. The horizontal distance between the first sensor and the center of mass is L1, and the horizontal distance between the second sensor and the center of mass is L2. The reaction force on the first sensor is F1, and the reaction force on the second sensor is F2. The mass of the printing platform 110 is m, and the inertial force on the printing platform 110 during the movement is F.

[0050] Among them, F=ma, a is the acceleration signal.

[0051] Based on the force analysis, we can get:

[0052]

[0053]

[0054] The sensitivity S1 of the first sensor and the sensitivity S2 of the second sensor may be respectively:

[0055]

[0056]

[0057] Wherein, V1 is a sensing signal of the first sensor, V2 is a sensing signal of the second sensor, and the sensing signals are voltage signals.

[0058] It is understood that the above only shows the sensitivity calculation method with two pressure sensors 130. If there are more pressure sensors 130, the pressure on each pressure sensor 130 can still be obtained through force analysis, and the sensitivity of the pressure sensor 130 can be calculated. This method is easy to implement and simple to operate.

[0059] In some embodiments, the predetermined motion law may include uniformly accelerated motion. Since uniformly accelerated motion theoretically has a constant acceleration, it can be easily detected and calculated.

[0060] In some embodiments, when the predetermined motion law is uniform acceleration motion, determining the acceleration signal from the predetermined motion law in step S220 may include: determining the instantaneous acceleration of the printing platform 110 at one moment during the motion or the average value of the instantaneous acceleration at multiple moments from the predetermined motion law as the acceleration signal. In some examples, the acceleration signal includes the acceleration of the printing platform 110 during the motion.

[0061] Acquiring corresponding sensing signals output by the N pressure sensors during the movement of the printing platform 110 in step S230 may include: for each pressure sensor 130, acquiring a sampling value of the output signal of the pressure sensor 130 during the movement of the printing platform 110 at one time or an average value of the sampling values ​​at multiple times as the sensing signal of the pressure sensor 130. In some examples, the sensing signal of the pressure sensor 130 includes a value corresponding to the sensing signal.

[0062] The sensitivity of each pressure sensor 130 can be calculated by calculating the instantaneous acceleration at a certain moment and the sampling value of the pressure sensor 130 at that moment, or calculating the average value of the instantaneous acceleration at multiple moments and the average value of the sampling values.

[0063] In other embodiments, the predetermined motion pattern may include reciprocating motion. It is understood that in the actual motion process, due to the flexibility, vibration, sensor noise, etc. of the motion mechanism, a relatively long sampling time is required to enable the pressure sensor 130 to obtain a stable output. If uniform acceleration motion is adopted, after a longer sampling time, the linear velocity of the printing platform 110 will be relatively large. For example, if the z-axis pulley is moving at 1m / s 2 The printing platform 110 is accelerated by an acceleration of 1 m / s and samples for 1 second. When the sampling is finished, the printing platform 110 needs to be accelerated to 1 m / s. This movement speed may require a higher cost (for example, a more powerful motor, a longer Z-axis stroke, etc.) for a 3D printer to achieve. The reciprocating motion allows the printing platform 110 to move back and forth within a certain displacement range, which can not only get rid of the limitation of the machine size, but also limit the linear speed within a certain range, thereby reducing the required machine cost and helping to calculate the sensitivity of the pressure sensor 130.

[0064] Figure 4 FIG. 4 is a flowchart of a method 400 for a 3D printer according to an embodiment of the present disclosure. Figure 4 In some embodiments, when the predetermined motion pattern is reciprocating motion, the method 400 may include: steps S410 to S480.

[0065] In step S410 , the printing platform 110 is controlled to move along the Z axis of the 3D printer according to a predetermined motion rule.

[0066] In step S420 , a discrete time series a(k) of acceleration of the printing platform 110 during the motion is determined from a predetermined motion law.

[0067] In step S430, Fourier transform is performed on the discrete time series a(k) to obtain a transformed acceleration data sequence A′(n).

[0068] In step S440, an acceleration data item with a predetermined sequence number is selected from the transformed acceleration data sequence A'(n) for calculating the acceleration signal.

[0069] In step S450, a discrete time series {v j (k)}, j = 1, 2, ..., N.

[0070] In step S460, for each discrete time series {v j (k)} is Fourier transformed to obtain the transformed sensing data sequence {V′ j (n)}.

[0071] In step S470, from each transformed sensing data sequence {V′ j (n)} selects a sensing data item with a predetermined serial number for calculating the corresponding sensing signal, wherein k is the sampling value serial number and k=0, 1, 2, ..., (T*fs), T is the sampling duration, fs is the sampling frequency, n is the Fourier transform value serial number and n=0, 1, 2, ..., (T*fs), and j is the serial number of each pressure sensor 130 in the N pressure sensors 130.

[0072] In step S480 , the sensitivity of each of the N pressure sensors 130 is determined based on the acceleration signal, the corresponding sensing signal, the mass of the printing platform 110 , and the corresponding positions of the N pressure sensors 130 relative to the center of mass of the printing platform 110 .

[0073] Among them, step S410 and step S480 are respectively the same as the above-mentioned step S210 and step S240, and the details can refer to the description of the above-mentioned embodiment. Steps S420 to S440 can be a specific implementation of step S220, and steps S450 to S470 can be a specific implementation of step S230. The processor can periodically output a control signal to control the motion of the printing platform 110, and fs can be the control frequency of the processor for motion control and the sampling frequency of the pressure sensor 130.

[0074] The acceleration signal can be represented by a discrete time series a(k), and the output signal of the pressure sensor 130 can also be represented by a discrete time series of sampling values ​​{v j (k)} represents that each pressure sensor 130 is sampled at a sampling frequency fs to obtain a discrete time series of sampled values ​​{v j (k)}.

[0075] Return to reference Figure 1 Taking the first sensor and the second sensor as examples, the acceleration signal can be represented as a discrete time series a(k). At the same time, the discrete time series v1(k) of the sampling values ​​of the first sensor and the discrete time series v2(k) of the sampling values ​​of the second sensor can be obtained by sampling.

[0076] Then, the discrete time series a(k) can be Fourier transformed to obtain the transformed acceleration data series A′(n). And the discrete time series v1(k) and v2(k) can be Fourier transformed to obtain the transformed sensing data series V′1(n) and V′2(n), respectively.

[0077] It can be understood that after Fourier transformation, the discrete time series a(k), v1(k) and v2(k) can be respectively expressed as the series A′(n), V′1(n), V′2(n) about the sequence number n, and each data item corresponding to n can represent a frequency component. By selecting the predetermined sequence number c corresponding to the 3D printer, the sensitivity of the pressure sensor 130 can be calculated, and c can be the frequency or frequency component of the predetermined motion law.

[0078] In some embodiments, calculating the modulus value |A′(c)| of the acceleration data item with a predetermined sequence number c in the sequence A′(n) as the acceleration signal, and calculating the corresponding sensing signal includes: calculating the modulus value |V′ corresponding to each sensing data item with the predetermined sequence number c j (c) | as the corresponding sensing signal.

[0079] In some examples, when the acceleration data item with a predetermined sequence number is itself a positive real number, the acceleration data item can be directly used as an acceleration signal, for example, the number of the acceleration data item with a predetermined sequence number is 1.

[0080] After the predetermined serial number c is selected, a(k), v1(k) and v2(k) after Fourier transformation can be respectively expressed as complex numbers A′(c), V′1(c) and V′2(c).

[0081] A′(c)=R+i*I

[0082] V′1(c)=R1+i*I1

[0083] V′2(c)=R2+i*I2

[0084] And the module values ​​corresponding to A′(c), V′1(c), and V′2(c) are:

[0085]

[0086]

[0087]

[0088] Then the sensitivity of the first sensor and the second sensor can be obtained:

[0089]

[0090]

[0091] It can be understood that due to the influence of noise, the acceleration signal and the sensing signal will have interference such as glitches. If only the acceleration signal and the sensing signal at a certain point are collected, the calculated sensitivity error will be large. After Fourier transform, all data points in the entire sampling time can be used as the basis for calculating the sensitivity, thereby reducing the influence of noise on the accuracy of the calculation results. Moreover, by comprehensively calculating multiple data points, the accuracy of sensitivity calibration can be further improved.

[0092] In some embodiments, the reciprocating motion is a simple harmonic motion with a frequency of F0 Hz, the acceleration data item with a predetermined sequence number is A′(F0*T), and each sensing data item with a predetermined sequence number is {V′ j (F0*T)}.

[0093] The displacement of simple harmonic motion changes with time according to the law of sine function or cosine function. Taking the sine function as an example, the discrete time series of acceleration a(k) can be expressed as:

[0094]

[0095] Wherein, A is the maximum amplitude of the reciprocating motion. The predetermined sequence number c=F0*T in step S440 and step S470 has a simple law of simple harmonic motion and is easier to calculate the sensitivity.

[0096] The present disclosure also provides a 3D printer, comprising: a printing platform 110, a processor and N pressure sensors 130, the printing platform 110 includes a printing plane 112 for carrying a printed object; each of the N pressure sensors 130 is configured to generate a sensing signal indicating a force applied to the printing plane 112, N being a positive integer greater than or equal to 1; the processor is configured to execute instructions to implement the above-mentioned method for a 3D printer.

[0097] The structures and functions of the printing platform 110, the processor and the N pressure sensors 130 may refer to the above-mentioned embodiments and will not be described in detail here.

[0098] The present disclosure also provides a non-transitory computer-readable storage medium storing computer instructions, wherein the computer instructions, when executed by a processor of a 3D printer, enable the 3D printer to implement the above-mentioned method for a 3D printer.

[0099] The present disclosure also provides a computer program product, including a computer program, wherein when the computer program is executed by a processor of a 3D printer, the 3D printer implements the above-mentioned method for a 3D printer.

[0100] It should be understood that in this specification, the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships or dimensions that are based on the orientations or positional relationships or dimensions shown in the accompanying drawings, and these terms are used only for the convenience of description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the scope of protection of the present disclosure.

[0101] In addition, the terms "first", "second", "third", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first", "second", "third" may explicitly or implicitly include one or more of the feature. In the description of the present disclosure, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0102] In the present disclosure, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present disclosure can be understood according to specific circumstances.

[0103] In the present disclosure, unless otherwise expressly specified and limited, a first feature being “above” or “below” a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being “above”, “above”, and “above” a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being “below”, “below”, and “below” a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0104] This specification provides many different embodiments or examples that can be used to implement the present disclosure. It should be understood that these different embodiments or examples are completely exemplary and are not intended to limit the scope of protection of the present disclosure in any way. Therefore, the scope of protection of the present disclosure should be based on the scope of protection defined by the attached claims.

Claims

1. A method for a 3D printer, the 3D printer comprising: A printing platform and N pressure sensors, wherein the printing platform includes a printing plane for carrying a printing object, each of the N pressure sensors is configured to generate a sensing signal in response to a force applied to the printing platform, N is a positive integer greater than or equal to 1, and the method includes: Controlling the printing platform to move along the Z axis of the 3D printer according to a predetermined motion law; the predetermined motion law is used to determine the acceleration of the printing platform during the movement; Obtaining values ​​corresponding to corresponding sensing signals output by the N pressure sensors during movement of the printing platform, the N pressure sensors being mounted to the printing platform; and Based on the acceleration of the printing platform during the movement corresponding to the predetermined movement law and the value corresponding to the corresponding sensing signal, the sensitivity of each of the N pressure sensors is determined.

2. The method according to claim 1, wherein: Determining the sensitivity of each of the N pressure sensors is further based on at least one of a mass of the printing platform and a corresponding position of the N pressure sensors relative to a center of mass of the printing platform.

3. The method according to claim 2, wherein: Determining the sensitivity of each of the N pressure sensors comprises: Determine corresponding reaction forces generated at the N pressure sensors by inertial forces to which the printing platform is subjected during movement based on the acceleration signal, the mass of the printing platform, and the corresponding positions of the N pressure sensors relative to the center of mass of the printing platform; and Based on the corresponding reaction forces and the corresponding values ​​of the corresponding sensing signals, the sensitivity of each of the N pressure sensors is determined.

4. The method according to any one of claims 1 to 3, wherein: The predetermined motion law includes uniformly accelerated motion or reciprocating motion.

5. The method according to any one of claims 1 to 4, wherein: The acceleration of the printing platform during the movement is determined based on the predetermined motion law.

6. The method according to claim 5, wherein: The predetermined motion law is uniformly accelerated motion, Wherein, determining the acceleration of the printing platform during the movement based on the predetermined motion law comprises: determining the instantaneous acceleration of the printing platform at one moment during the movement or the average value of the instantaneous acceleration at multiple moments from the predetermined motion law as the acceleration of the printing platform during the movement, and Among them, obtaining the values ​​corresponding to the corresponding sensing signals output by the N pressure sensors during the movement of the printing platform includes: for each pressure sensor, obtaining the sampling value of the output signal of the pressure sensor during the movement of the printing platform at the one moment or the average value of the sampling values ​​at the multiple moments as the value corresponding to the corresponding sensing signal.

7. The method according to claim 5, wherein: The predetermined motion law is reciprocating motion, Wherein, determining the acceleration from the predetermined motion law comprises: Determining a discrete time series a(k) of acceleration of the printing platform during the motion from the predetermined motion law; Performing Fourier transformation on the discrete time series a(k) to obtain a transformed acceleration data sequence A′(n); and selecting acceleration data items with predetermined serial numbers from the transformed acceleration data sequence A′(n) for determining the acceleration of the printing platform during the movement, and Wherein, obtaining values ​​corresponding to corresponding sensing signals output by the N pressure sensors during the movement of the printing platform includes: Obtain a discrete time sequence of sampled values ​​of the corresponding output signals of the N pressure sensors during the movement of the printing platform {v j (k)},j=1,2,…,N; For each discrete time series {v j (k)} is Fourier transformed to obtain the transformed sensing data sequence {V′ j (n)}; and From each of the transformed sensing data sequences {V′ j (n)} selects the sensing data item with the predetermined sequence number to determine the value corresponding to the corresponding sensing signal, Among them, k is the sampling value number and k=0,1,2,…,(T*fs), T is the sampling duration, fs is the sampling frequency, n is the Fourier transform value number and n=0,1,2,…,(T*fs), and j is the number of each pressure sensor in the N pressure sensors.

8. The method according to claim 7, wherein: The selecting the acceleration data item with a predetermined serial number for determining the acceleration of the printing platform during the movement comprises: calculating the modulus value of the acceleration data item with the predetermined serial number as the acceleration of the printing platform during the movement, and The selecting the sensing data item with the predetermined sequence number to determine the value corresponding to the corresponding sensing signal includes: calculating the modulus value of each sensing data item with the predetermined sequence number as the value corresponding to the corresponding sensing signal.

9. The method according to claim 7 or 8, in, The reciprocating motion is a simple harmonic motion with a frequency of F0 Hz. wherein the acceleration data item having the predetermined sequence number is A′(F0*T), and Wherein, each of the sensing data items having the predetermined sequence number is {V′ j (F0*T)}.

10. A 3D printer, comprising: A printing platform, the printing platform comprising a printing plane for carrying a printed object; N pressure sensors, each of the N pressure sensors being configured to generate a sensing signal in response to a force applied to the printing platform, N being a positive integer greater than or equal to 1; as well as A processor, wherein the processor is configured to execute instructions to implement the method according to any one of claims 1 to 9.

11. A non-transitory computer-readable storage medium storing computer instructions, wherein: When the computer instructions are executed by the processor of the 3D printer of claim 10 , the 3D printer is caused to implement the method according to any one of claims 1 to 9 .

12. A computer program product comprising a computer program, in, When the computer program is executed by a processor of the 3D printer of claim 10 , the computer program enables the 3D printer to implement the method according to any one of claims 1 to 9 .

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