Angular position measurement method and device

Abstract

The present invention relates to the field of angle measurement technology, and in particular to a method and device for measuring angular position. The method of the present invention first obtains a first standard magnetic field strength array and a second standard magnetic field strength array; then, a first array is constructed based on the magnetic field strength signals currently returned by the multiple magnetic field sensors, and a first cosine value and a first sine value are determined based on the first array, the number of sinusoidal wave cycles in the sinusoidal wave magnetic field, the first standard magnetic field strength array, and the second standard magnetic field strength array; then, the quadrant in which the relative angular position is located is determined based on the sign of the first cosine value and the sign of the first sine value; finally, the angular position is determined based on the standard angular position, the quadrant in which the relative angular position is located, and the first cosine value, or based on the standard angular position, the quadrant in which the relative angular position is located, and the first sine value. The present invention achieves high measurement accuracy while meeting reliability requirements.

Description

Technical Field

[0001] The present invention relates to the technical field of angle measurement, and in particular to a method and device for measuring an angular position. Background Art

[0002] In various motion control automatic control systems such as robot joints and aircraft servos, angular position / angular velocity are very important physical parameters of all rotating parts and must be detected in real time by corresponding sensors to form closed-loop control.

[0003] According to the working principle and form, traditional angular position / angular velocity sensors can be roughly divided into the following three categories: pulse type (photoelectric pulse type, magnetoelectric pulse type) angular position / angular velocity sensors, induction type (electromagnetic induction, magnetoresistive induction) angular position / angular velocity sensors, and potentiometer type angular position / angular velocity sensors.

[0004] Switch-type Hall effect sensors are pulse sensors that are simple to use, but their accuracy is poor, making them difficult to use in high-precision applications. Photoelectric encoders are also pulse sensors that can be highly accurate, but their reliability and environmental adaptability are poor, limiting their application areas. Resolvers are typical inductive sensors that offer a certain level of accuracy and reliability, but they require extremely high installation precision and pose challenges with long-term operational stability. Potentiometer-type angular position / angular velocity sensors, on the other hand, suffer from challenges such as short mechanical contact life and poor interference immunity for small signal transmission, making them difficult to use over long distances or in complex electromagnetic environments.

[0005] It can be seen that the above-mentioned various forms of sensors have their own characteristics, but often a single technical indicator is outstanding, while other technical indicators have obvious shortcomings, making it difficult to meet the special needs of high reliability and high precision at the same time.

[0006] Based on this, it is necessary to develop and design an angular position measurement method. Summary of the Invention

[0007] The embodiments of the present invention provide an angular position measurement method and device, which are used to solve the problem in the prior art that angular position measurement is difficult to achieve both high reliability and high precision.

[0008] In a first aspect, an embodiment of the present invention provides an angular position measurement system, comprising:

[0009] A magnetic field excitation mechanism, a plurality of magnetic field sensors, and a signal processing unit;

[0010] The plurality of magnetic field sensors are electrically connected to the signal processing unit;

[0011] The magnetic field excitation mechanism generates a sinusoidal magnetic field of at least one complete cycle on the circumference;

[0012] The plurality of magnetic field sensors are distributed in an array along the central circumference of the sinusoidal magnetic field;

[0013] When the multiple magnetic field sensors respectively return magnetic field strength signals at their respective locations, the signal processing unit determines the angular position of the sinusoidal magnetic field relative to the multiple magnetic field sensors based on the number of sinusoidal wave cycles in the sinusoidal wave magnetic field and the multiple magnetic field strength signals.

[0014] In one possible implementation, the magnetic field excitation mechanism includes a magnetic ring and a plurality of magnetic steels;

[0015] The plurality of magnetic steels are fixedly arranged on the magnetic ring in a circumferential array, and the magnetic pole directions of the plurality of magnetic steels are alternately arranged along the axial direction of the magnetic ring;

[0016] The magnetic ring is a poor conductor of magnetism.

[0017] In a second aspect, an embodiment of the present invention provides an angular position measurement method, comprising:

[0018] Obtaining a first standard magnetic field strength array and a second standard magnetic field strength array, wherein the first standard magnetic field strength array and the second standard magnetic field strength array are arrays constructed based on multiple standard magnetic field strength signals, and the standard magnetic field signals are magnetic field strength signals returned by the magnetic field sensors when the angle of the sinusoidal wave magnetic field relative to the multiple magnetic field sensors is at a standard angular position;

[0019] constructing a first array based on the magnetic field strength signals currently returned by the multiple magnetic field sensors, and determining a first cosine value and a first sine value based on the first array, the number of sinusoidal wave cycles in the sinusoidal wave magnetic field, the first standard magnetic field strength array, and the second standard magnetic field strength array;

[0020] determining the quadrant in which the relative angular position is located according to the sign of the first cosine value and the sign of the first sine value;

[0021] The angular position is determined according to the standard angular position, the quadrant in which the relative angular position is located, and at least one of the first cosine value and the first sine value.

[0022] In one possible implementation, constructing a first array based on the magnetic field strength signals currently returned by the multiple magnetic field sensors, and determining a first cosine value and a first sine value based on the first array, the number of sinusoidal wave cycles in the sinusoidal wave magnetic field, the first standard magnetic field strength array, and the second standard magnetic field strength array includes:

[0023] Acquire magnetic field strength signals currently returned by the multiple magnetic field sensors;

[0024] Arranging the magnetic field strength signals currently returned by the plurality of magnetic field sensors according to the locations of the magnetic field sensors to obtain an intermediate array;

[0025] reconstructing and normalizing the sinusoidal magnetic field according to the magnetic field intensity value, the number of sinusoidal wave cycles in the sinusoidal wave magnetic field, the number of the plurality of magnetic field sensors, and the intermediate array to obtain the first array;

[0026] The dot product of the first array and the first standard magnetic field strength array and the dot product of the first array and the second standard magnetic field strength array are calculated respectively to obtain the first cosine value and the first sine value.

[0027] In one possible implementation, determining the first cosine value and the first sine value based on the first array, the number of sinusoidal wave periods in the sinusoidal wave magnetic field, the first standard magnetic field strength array, and the second standard magnetic field strength array includes:

[0028] The first cosine value is determined according to a first formula, wherein the first formula is:

[0029]

[0030] Where, is the first cosine value, The first array numerical values, is the number of multiple magnetic field sensors, The first standard magnetic field strength array data, is a sine function, is pi, is the number of sine wave cycles in the sinusoidal magnetic field, is the standard angular position;

[0031] The first sine value is determined according to a second formula, wherein the second formula is:

[0032]

[0033] Where, is the first sine value, The first data, is the cosine function.

[0034] In one possible implementation, determining the quadrant in which the relative angular position is located according to the sign of the first cosine value and the sign of the first sine value includes:

[0035] If the first cosine value is positive and the first sine value is positive, the relative angular position is in the first quadrant;

[0036] If the first cosine value is negative and the first sine value is positive, the relative angular position is in the second quadrant;

[0037] If the first cosine value is negative and the first sine value is negative, the relative angular position is in the third quadrant;

[0038] If the first cosine value is positive and the first sine value is negative, the relative angular position is in the fourth quadrant.

[0039] In one possible implementation, determining the angular position according to the standard angular position, the quadrant in which the relative angular position is located, and at least one of the first cosine value and the first sine value includes:

[0040] The angular position is determined according to a third formula or a fourth formula, wherein the third formula is:

[0041]

[0042] Where, is the relative angular position, is the inverse cosine function, is the angular position, is the standard angular position, is the first cosine value, is the number of sine wave cycles in the sinusoidal magnetic field, For the first quadrant, For the second quadrant, For the third quadrant, The fourth quadrant, is pi;

[0043] The fourth formula is:

[0044]

[0045] Where, is the inverse sine function, is the first sine value.

[0046] In a third aspect, an embodiment of the present invention provides an angular position measurement device for implementing the angular position measurement method described in the second aspect or any possible implementation of the second aspect, the angular position measurement device comprising:

[0047] a standard magnetic field strength acquisition module, configured to acquire a first standard magnetic field strength array and a second standard magnetic field strength array, wherein the first standard magnetic field strength array and the second standard magnetic field strength array are arrays constructed based on a plurality of standard magnetic field strength signals, and the standard magnetic field signals are magnetic field strength signals returned by the magnetic field sensors when the angle of the sinusoidal magnetic field relative to the plurality of magnetic field sensors is at a standard angular position;

[0048] an angular position data extraction module, configured to construct a first array based on the magnetic field strength signals currently returned by the plurality of magnetic field sensors, and determine a first cosine value and a first sine value based on the first array, the number of sinusoidal wave cycles in the sinusoidal wave magnetic field, the first standard magnetic field strength array, and the second standard magnetic field strength array;

[0049] a quadrant positioning module, configured to determine the quadrant in which the relative angular position is located according to the sign of the first cosine value and the sign of the first sine value;

[0050] as well as,

[0051] An angular position determination module is configured to determine the angular position based on the standard angular position, the quadrant where the relative angular position is located, and the first cosine value, or based on the standard angular position, the quadrant where the relative angular position is located, and the first sine value.

[0052] In a fourth aspect, an embodiment of the present invention provides an electronic device comprising a memory and a processor, wherein the memory stores a computer program that can be run on the processor, and when the processor executes the computer program, it implements the steps of the method described in the second aspect or any possible implementation of the second aspect.

[0053] In a fifth aspect, an embodiment of the present invention provides a computer-readable storage medium, which stores a computer program. When the computer program is executed by a processor, it implements the steps of the method described in the second aspect or any possible implementation of the second aspect.

[0054] Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

[0055] The angular position measurement system disclosed in the embodiment of the present invention obtains the magnetic field strength signal of the magnetic field excitation mechanism through multiple magnetic field sensors. Since the magnetic field surface induction measurement method is adopted, the high precision characteristics of the sensor and the stability and reliability of long-term application in harsh environments are guaranteed.

[0056] An embodiment of the present invention discloses an angular position measurement method. The method first obtains a first standard magnetic field strength array and a second standard magnetic field strength array, wherein the first standard magnetic field strength array and the second standard magnetic field strength array are arrays constructed based on multiple standard magnetic field strength signals, and the standard magnetic field signals are magnetic field strength signals returned by the magnetic field sensors when the angle of the sinusoidal wave magnetic field relative to the multiple magnetic field sensors is a standard angular position. Then, a first array is constructed based on the magnetic field strength signals currently returned by the multiple magnetic field sensors, and a first cosine value and a first sine value are determined based on the first array, the number of sinusoidal wave cycles in the sinusoidal wave magnetic field, the first standard magnetic field strength array, and the second standard magnetic field strength array. Then, the quadrant in which the relative angular position is located is determined based on the sign of the first cosine value and the sign of the first sine value. Finally, the angular position is determined based on the standard angular position, the quadrant in which the relative angular position is located, and the first cosine value, or based on the standard angular position, the quadrant in which the relative angular position is located, and the first sine value. The angular position measurement method and system of the embodiments of the present invention rely on the magnetic field strength signal of a sinusoidal magnetic field and the number of sinusoidal wave cycles to determine the angular position. The system has a simple structure and strong vibration resistance, and is therefore relatively reliable. The angular position is determined by reconstructing and normalizing multiple magnetic field strength signals and performing a dot product operation with a standard magnetic field strength array. The accuracy can reach a high level, that is, high measurement accuracy is achieved while meeting reliability requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments or descriptions of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0058] Figure 1 This is a schematic diagram of the relative positions of the magnetic field excitation mechanism and the magnetic field sensor provided in an embodiment of the present invention;

[0059] Figure 2 is a schematic diagram of a magnetic field excitation mechanism provided by an embodiment of the present invention;

[0060] Figure 3 1 is a schematic diagram of a sine wave magnetic field with 6 complete cycles provided by an embodiment of the present invention;

[0061] Figure 4 This is a schematic diagram of a fixing method for multiple magnetic field sensors provided by an embodiment of the present invention;

[0062] Figure 5 is a flow chart of an angular position measurement method provided by an embodiment of the present invention;

[0063] Figure 6 is a functional block diagram of an angular position measurement device provided by an embodiment of the present invention;

[0064] Figure 7 This is a functional block diagram of an electronic device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0065] In the following description, specific details such as particular system structures and techniques are provided for purposes of illustration, not limitation, to facilitate a thorough understanding of the embodiments of the present invention. However, it will be apparent to those skilled in the art that the present invention may be practiced in alternative embodiments without these specific details. In other instances, detailed descriptions of well-known systems, devices, and methods are omitted so as not to obscure the description of the present invention with unnecessary detail.

[0066] In order to make the objectives, technical solutions and advantages of the present invention more clear, the following will be described through specific implementation methods in conjunction with the accompanying drawings.

[0067] The following is a detailed description of an embodiment of the present invention. This example is implemented based on the technical solution of the present invention, and provides a detailed implementation method and specific operation process, but the protection scope of the present invention is not limited to the following embodiment.

[0068] In a first aspect, an embodiment of the present invention provides an angular position measurement system, comprising:

[0069] A magnetic field excitation mechanism, a plurality of magnetic field sensors, and a signal processing unit;

[0070] The plurality of magnetic field sensors are electrically connected to the signal processing unit;

[0071] The magnetic field excitation mechanism generates a sinusoidal magnetic field of at least one complete cycle on the circumference;

[0072] The plurality of magnetic field sensors are distributed in an array along the central circumference of the sinusoidal magnetic field;

[0073] When the multiple magnetic field sensors respectively return magnetic field strength signals at their respective locations, the signal processing unit determines the angular position of the sinusoidal magnetic field relative to the multiple magnetic field sensors based on the number of sinusoidal wave cycles in the sinusoidal wave magnetic field and the multiple magnetic field strength signals.

[0074] In one possible implementation, the magnetic field excitation mechanism includes a magnetic ring and a plurality of magnetic steels;

[0075] The plurality of magnetic steels are fixedly arranged on the magnetic ring in a circumferential array, and the magnetic pole directions of the plurality of magnetic steels are alternately arranged along the axial direction of the magnetic ring;

[0076] The magnetic ring is a poor conductor of magnetism.

[0077] For example, Figure 1 The magnetic field excitation mechanism 10 generates a circumferentially distributed sinusoidal magnetic field in the air gap, and a detection and conditioning circuit board 20 fixed with multiple magnetic field sensors detects the magnetic field and performs angular position and / or angular velocity detection based on the magnetic field.

[0078] In applications, the magnetic field excitation mechanism 10 and the circumferentially distributed sinusoidal magnetic field it generates are typically rotated synchronously with the component under test, while the detection and conditioning circuit board 20 is stationary. Alternatively, conversely, the magnetic field excitation mechanism 10 and the circumferentially distributed sinusoidal magnetic field it generates are stationary, while the detection and conditioning circuit board 20 and the component under test are rotated synchronously.

[0079] like Figure 2 As shown, the embodiment of the present invention generates a sine wave magnetic field with 6 cycles. The circumferentially distributed spatial sine wave magnetic field corresponds to a six-pole structure, forming 6 complete electrical cycles within one mechanical cycle (360°).

[0080] like Figure 3 As shown, in one embodiment, the magnetic field excitation mechanism 10 includes a magnetic ring 11 , a plurality of circular grooves 12 provided on the magnetic ring, and magnetic steels 13 fixed on the circular grooves 12 .

[0081] Multiple circular grooves 12 are alternately filled with magnets 13 at their north and south poles. The material of the magnetic ring 11 is a poor conductor of magnetism. In one application scenario, the depth of the circular grooves 12 in the magnetic ring 11 is uniform. The magnets 13 are magnetized axially, and the magnetization strength of the multiple magnets 13 is uniform.

[0082] The distribution of the circularly distributed spatial sinusoidal magnetic field on the circular surface surrounded by the linear Hall sensor array is in a sinusoidal form.

[0083] The detection and conditioning circuit board 20 is composed of one or more circuit boards.

[0084] In one application scenario, the detection and conditioning circuit board 20 includes a Hall sensor array 21 consisting of 48 linear Hall sensors, a sampling and holding circuit, a conditioning and filtering circuit, an analog switch circuit, an AD conversion circuit, and a CPU.

[0085] like Figure 4 As shown, the Hall sensor array 21 on a detection and conditioning circuit board 20 is evenly arranged along a circle, and the radius of the circle is the same as the radius of the magnetic field in the circumferential distribution space.

[0086] The sample and hold circuit is used to sample and hold the spatial magnetic field at a certain moment, and is used for subsequent circuits and program processing.

[0087] The conditioning and filtering circuit is used to perform level conversion and filtering on the front-stage signal.

[0088] The analog switch circuit is used to perform time-sharing switching on the 48 linear Hall sensor signals.

[0089] The AD conversion circuit is used to convert analog quantities into digital quantities and send the conversion results to the CPU.

[0090] The CPU is used to control the entire sensor system and execute the angular position / angular velocity calculation algorithm.

[0091] Preferably, the relationship between the analog electrical signal output by the Hall sensor array 21 and the intensity of the induced magnetic field is linear. The better the linearity, the better the effect of the CPU in reconstructing the spatial magnetic field.

[0092] Preferably, in order to prevent the Hall sensor array 21 from outputting saturation or too small an amplitude to affect sensor accuracy, the magnetic field intensity generated by the magnetic field excitation mechanism 10 should be constrained within a certain range.

[0093] Preferably, to prevent the Hall sensor array 21 from outputting saturation or too low an amplitude that affects sensor accuracy, a reasonable air gap should be set between the magnetic field excitation mechanism 10 and the detection and conditioning circuit board 20. The size of the air gap is subject to both mechanical and reliability constraints.

[0094] Preferably, in order to avoid output saturation of the Hall sensor array 21 , the Hall sensor should be selected with a suitable detection sensitivity when there is a certain air gap distance between the magnetic field excitation mechanism 10 and the detection and conditioning circuit board 20 .

[0095] Preferably, in order to avoid output saturation of the Hall sensor array 21, the conditioning filter circuit should be set to a reasonable amplification factor under a certain air gap distance between the magnetic field excitation mechanism 10 and the detection and conditioning circuit board 20 and a certain sensitivity of the Hall sensor.

[0096] Preferably, after the above optimization, the peak-to-peak value of the signal input to the AD conversion circuit is between 1 / 2 and 3 / 4 of the effective input range of the AD conversion circuit.

[0097] In a second aspect, an embodiment of the present invention provides an angular position measurement method.

[0098] Figure 5 This is a flow chart of an angular position measurement method provided in an embodiment of the present invention.

[0099] like Figure 5 As shown, it shows a flowchart of the implementation method of the angular position measurement method provided by an embodiment of the present invention, which is detailed as follows:

[0100] In step 501, a first standard magnetic field strength array and a second standard magnetic field strength array are obtained, wherein the first standard magnetic field strength array and the second standard magnetic field strength array are respectively arrays constructed based on multiple standard magnetic field strength signals, and the standard magnetic field signal is the magnetic field strength signal returned by the magnetic field sensor when the angle of the sinusoidal wave magnetic field relative to the multiple magnetic field sensors is a standard angular position.

[0101] In step 502, a first array is constructed based on the magnetic field strength signals currently returned by the multiple magnetic field sensors, and a first cosine value and a first sine value are determined based on the first array, the number of sinusoidal wave cycles in the sinusoidal wave magnetic field, the first standard magnetic field strength array, and the second standard magnetic field strength array.

[0102] In some embodiments, constructing a first array based on the magnetic field strength signals currently returned by the plurality of magnetic field sensors, and determining a first cosine value and a first sine value based on the first array, the number of sinusoidal wave cycles in the sinusoidal wave magnetic field, the first standard magnetic field strength array, and the second standard magnetic field strength array includes:

[0103] Acquire magnetic field strength signals currently returned by the multiple magnetic field sensors;

[0104] Arranging the magnetic field strength signals currently returned by the plurality of magnetic field sensors according to the locations of the magnetic field sensors to obtain an intermediate array;

[0105] reconstructing and normalizing the sinusoidal magnetic field according to the magnetic field intensity value, the number of sinusoidal wave cycles in the sinusoidal wave magnetic field, the number of the plurality of magnetic field sensors, and the intermediate array to obtain the first array;

[0106] The dot product of the first array and the first standard magnetic field strength array and the dot product of the first array and the second standard magnetic field strength array are calculated respectively to obtain the first cosine value and the first sine value.

[0107] In some embodiments, determining the first cosine value and the first sine value based on the first array, the number of sinusoidal wave cycles in the sinusoidal wave magnetic field, the first standard magnetic field strength array, and the second standard magnetic field strength array includes:

[0108] The first cosine value is determined according to a first formula, wherein the first formula is:

[0109]

[0110] Where, is the first cosine value, The first array numerical values, is the number of multiple magnetic field sensors, The first standard magnetic field strength array data, is a sine function, is pi, is the number of sine wave cycles in the sinusoidal magnetic field, is the standard angular position;

[0111] The first sine value is determined according to a second formula, wherein the second formula is:

[0112]

[0113] Where, is the first sine value, The first data, is the cosine function.

[0114] For example, to better illustrate the highly reliable and high-precision angular position / angular velocity measurement method provided by an embodiment of the present invention, the following description is first made:

[0115] Note 1: The rotating part or equipment drives the magnetic field excitation mechanism to rotate synchronously on the same axis. Assume that its angular position is , the angular velocity is , time is t;

[0116] Explanation 2: When stationary, the magnetic field excitation mechanism generates a sinusoidal spatial sine wave magnetic field on the surface of the linear Hall sensor array. The number of sine cycles is 6 and the amplitude is , the number of linear Hall sensors is 48;

[0117] Note 3: Assumption The number of the linear Hall sensor ranges from 1 to 48.

[0118] Note 4: Assumption It is the linear gain of the magnetic field strength sensed by the linear Hall sensor and the output analog electrical signal, which is a constant.

[0119] Before determining the angular position, a standard angular position is usually preset, and the first and second standard magnetic field strength arrays are determined based on this standard angular position. The characterization angle refers to the angle of the magnetic field excitation mechanism relative to the reference sensor in the multiple magnetic field sensors.

[0120] For example, Figure 3 The magnetic field generated by the magnetic field excitation mechanism Phase and Figure 4When the 1# magnetic field sensor is facing the center, the phases of the sine wave positions of the 48 magnetic field sensors are obtained, and then the first standard magnetic field strength array and the second standard magnetic field strength array are obtained according to the phases corresponding to the 48 magnetic field sensors:

[0121]

[0122]

[0123] The first standard magnetic field strength array data, The first data, is pi, is the number of sine wave cycles in the sinusoidal magnetic field, is the standard angular position, is the number of magnetic field sensors.

[0124] In this embodiment, the standard angular position is 0, the number of magnetic field sensors is 48, and the number of sine wave cycles in the sine wave magnetic field is 6. Then the first standard magnetic field strength array and the second standard magnetic field strength array are:

[0125]

[0126]

[0127] The magnetic field excitation mechanism generates a spatial sinusoidal magnetic field with alternating sinusoidal distribution. The distribution of magnetic field intensity in the 360° circumference of the plane where the magnetic field sensor array is located is:

[0128]

[0129] When the magnetic field excitation mechanism rotates synchronously with the measured component, the sinusoidal magnetic field will also rotate synchronously at the same rate. The distribution of the magnetic field intensity in the 360° circumference of the plane where the magnetic field sensor array is located changes with time as follows:

[0130]

[0131] The linear Hall sensor array evenly distributed along the circumference senses an analog electrical signal that is proportional to the magnetic field strength at that location. Taking a single linear Hall sensor as an example, the relationship between the magnitude of the analog electrical signal it outputs and the magnitude of the sensed magnetic field strength is: The change of the analog electrical signal output by each linear Hall sensor over time is .

[0132] At the same time, the analog electrical signal of the magnetic field sensor array is sampled and held. The sampling and holding method can select the CPU on-chip ADC or a dedicated analog-to-digital converter to convert the analog electrical signal into a digital electrical signal.

[0133] The magnetic field intensity array of the spatial sinusoidal magnetic field based on the spatial sampling points is reconstructed in the CPU and normalized. The obtained normalized array is expressed as: , which represents the first numerical values.

[0134] The array obtained above is dot-producted with the first standard magnetic field strength array and the second standard magnetic field strength array obtained previously to obtain the first cosine value and the first sine value. Specifically, the first cosine value is obtained by applying the first formula:

[0135]

[0136] Where, is the first cosine value, The first array numerical values, is the number of multiple magnetic field sensors, The first standard magnetic field strength array data, is a sine function, is pi, is the number of sine wave cycles in the sinusoidal magnetic field, is the standard angular position;

[0137] Apply the second formula to obtain the first sine value:

[0138]

[0139] Where, is the first sine value, The first data, is the cosine function.

[0140] Based on the above cosine and sine values, the angular position can be obtained through subsequent steps.

[0141] In step 503, the quadrant in which the relative angular position is located is determined according to the sign of the first cosine value and the sign of the first sine value.

[0142] In some embodiments, determining the quadrant in which the relative angular position is located based on the sign of the first cosine value and the sign of the first sine value includes:

[0143] If the first cosine value is positive and the first sine value is positive, the relative angular position is in the first quadrant;

[0144] If the first cosine value is negative and the first sine value is positive, the relative angular position is in the second quadrant;

[0145] If the first cosine value is negative and the first sine value is negative, the relative angular position is in the third quadrant;

[0146] If the first cosine value is positive and the first sine value is negative, the relative angular position is in the fourth quadrant.

[0147] For example, before determining the angular position, it is necessary to clarify the quadrant in which the relative angular position is located. Specifically, the quadrant of the angular position is determined based on the sign of the first cosine value and the sign of the first sine value. Specifically:

[0148] 1) The first cosine value is positive, the first sine value is positive, and the relative angular position In the first quadrant; 2) the first cosine value is negative, the first sine value is positive, the relative angular position In the second quadrant; 3) The first cosine value is negative, the first sine value is negative, and the relative angular position In the third quadrant; 4) the first cosine value is positive, the first sine value is negative, and the relative angular position In the fourth quadrant.

[0149] In step 504, the angular position is determined according to the standard angular position, the quadrant in which the relative angular position is located, and at least one of the first cosine value and the first sine value.

[0150] In some embodiments, determining the angular position based on the standard angular position, the quadrant in which the relative angular position is located, and at least one of the first cosine value and the first sine value includes:

[0151] The angular position is determined according to a third formula or a fourth formula, wherein the third formula is:

[0152]

[0153] Where, is the relative angular position, is the inverse cosine function, is the angular position, is the standard angular position, is the first cosine value, is the number of sine wave cycles in the sinusoidal magnetic field, For the first quadrant, For the second quadrant, For the third quadrant, The fourth quadrant, is pi;

[0154] The fourth formula is:

[0155]

[0156] Where, is the inverse sine function, is the first sine value.

[0157] For example, in determining the angular position, the relative angular position is first calculated based on the first cosine value or the first sine value, and then the angular position is determined based on the relative angular position, the quadrant in which the relative angular position is located, and the standard angular position. Specifically, when determining the angular position based on the first cosine value, the third formula is applied:

[0158]

[0159] Where, is the relative angular position, is the inverse cosine function, is the angular position, is the standard angular position, is the first cosine value, is the number of sine wave cycles in the sinusoidal magnetic field, For the first quadrant, For the second quadrant, For the third quadrant, The fourth quadrant, is pi;

[0160] When determining based on the first sine value, the fourth formula applies:

[0161]

[0162] Where, is the inverse sine function, is the first sine value.

[0163] The third formula and the fourth formula respectively illustrate performing arccosine and arcsine calculations based on the first cosine value and the first sine value, and determining the relative angular position based on the calculation results.

[0164] In another scenario, the tangent value or cotangent value can be determined using the first cosine value and the first sine value, and the angular position can be determined by performing an inverse tangent or inverse cotangent calculation on the tangent value or cotangent value. It should be noted that this scenario, in which the angular position is determined based on both the first cosine value and the first sine value, falls within the scope of protection of this application.

[0165] After obtaining the above angular position, when the angular velocity needs to be obtained, the angular position is calculated twice continuously within a specific time interval, and the angular velocity can be obtained by differentiation.

[0166] In an embodiment of the angular position measurement method of the present invention, a first standard magnetic field strength array and a second standard magnetic field strength array are first acquired, wherein the first standard magnetic field strength array and the second standard magnetic field strength array are arrays constructed based on multiple standard magnetic field strength signals, and the standard magnetic field signals are magnetic field strength signals returned by the magnetic field sensors when the angle of the sinusoidal wave magnetic field relative to the multiple magnetic field sensors is a standard angular position. Then, a first array is constructed based on the magnetic field strength signals currently returned by the multiple magnetic field sensors, and a first cosine value and a first sine value are determined based on the first array, the number of sinusoidal wave cycles in the sinusoidal wave magnetic field, the first standard magnetic field strength array, and the second standard magnetic field strength array. Then, the quadrant in which the relative angular position is located is determined based on the sign of the first cosine value and the sign of the first sine value. Finally, the angular position is determined based on the standard angular position, the quadrant in which the relative angular position is located, and the first cosine value, or based on the standard angular position, the quadrant in which the relative angular position is located, and the first sine value. The angular position measurement method and system of the embodiments of the present invention rely on the magnetic field strength signal of a sinusoidal magnetic field and the number of sinusoidal wave cycles to determine the angular position. The system has a simple structure and strong vibration resistance, and is therefore relatively reliable. The angular position is determined by reconstructing and normalizing multiple magnetic field strength signals and performing a dot product operation with a standard magnetic field strength array. The accuracy can reach a high level, that is, high measurement accuracy is achieved while meeting reliability requirements.

[0167] It should be understood that the size of the serial numbers of each step in the above embodiment does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiment of the present invention.

[0168] The following is an embodiment of the device of the present invention. For details not described in detail, please refer to the corresponding method embodiment described above.

[0169] Figure 6 This is a functional block diagram of an angular position measuring device provided by an embodiment of the present invention, referring to Figure 6 The angular position measuring device includes: a standard magnetic field strength acquisition module 601, an angular position data extraction module 602, a quadrant positioning module 603 and an angular position determination module 604, wherein:

[0170] a standard magnetic field strength acquisition module 601, configured to acquire a first standard magnetic field strength array and a second standard magnetic field strength array, wherein the first standard magnetic field strength array and the second standard magnetic field strength array are arrays constructed based on a plurality of standard magnetic field strength signals, and the standard magnetic field signals are magnetic field strength signals returned by the magnetic field sensors when the angle of the sinusoidal magnetic field relative to the plurality of magnetic field sensors is at a standard angular position;

[0171] an angular position data extraction module 602, configured to construct a first array based on the magnetic field strength signals currently returned by the plurality of magnetic field sensors, and determine a first cosine value and a first sine value based on the first array, the number of sinusoidal wave cycles in the sinusoidal wave magnetic field, the first standard magnetic field strength array, and the second standard magnetic field strength array;

[0172] a quadrant positioning module 603, configured to determine the quadrant in which the relative angular position is located according to the sign of the first cosine value and the sign of the first sine value;

[0173] The angular position determination module 604 is configured to determine the angular position according to the standard angular position, the quadrant where the relative angular position is located, and the first cosine value, or according to the standard angular position, the quadrant where the relative angular position is located, and the first sine value.

[0174] Figure 7 : is a functional block diagram of an electronic device provided by an embodiment of the present invention. Figure 7 As shown, the electronic device 7 of this embodiment includes: a processor 700 and a memory 701, wherein the memory 701 stores a computer program 702 that can be run on the processor 700. When the processor 700 executes the computer program 702, the steps in the above-mentioned angular position measurement methods and embodiments are implemented, for example Figure 1 Steps 101 to 104 are shown.

[0175] Illustratively, the computer program 702 may be divided into one or more modules / units, and the one or more modules / units are stored in the memory 701 and executed by the processor 700 to implement the present invention.

[0176] The electronic device 7 may be a computing device such as a desktop computer, a notebook, a PDA, or a cloud server. The electronic device 7 may include, but is not limited to, a processor 700 and a memory 701. Those skilled in the art will understand that Figure 7 It is only an example of the electronic device 7 and does not constitute a limitation of the electronic device 7. It may include more or fewer components than shown in the figure, or a combination of certain components, or different components. For example, the electronic device 7 may also include input and output devices, network access devices, buses, etc.

[0177] The processor 700 may be a central processing unit (CPU), other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA), other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor.

[0178] The memory 701 may be an internal storage unit of the electronic device 7, such as a hard drive or memory of the electronic device 7. The memory 701 may also be an external storage device of the electronic device 7, such as a plug-in hard drive, a Smart Media Card (SMC), a Secure Digital (SD) card, a flash memory card, etc. equipped on the electronic device 7. Furthermore, the memory 701 may include both an internal storage unit of the electronic device 7 and an external storage device. The memory 701 is used to store the computer program 702 and other programs and data required by the electronic device 7. The memory 701 may also be used to temporarily store data that has been output or is about to be output.

[0179] Those skilled in the art can clearly understand that, for the convenience and brevity of description, only the division of the above-mentioned functional units and modules is used as an example for illustration. In actual applications, the above-mentioned functions can be distributed and completed by different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the implementation method can be integrated into one processing unit, or each unit can exist physically alone, or two or more units can be integrated into one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of software functional units. In addition, the specific names of the functional units and modules are only for the convenience of distinguishing each other, and are not used to limit the scope of protection of this application. The specific working process of the units and modules in the above-mentioned system can refer to the corresponding process in the aforementioned method implementation method, and will not be repeated here.

[0180] In the above embodiments, the description of each embodiment has its own focus. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0181] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians may use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the present invention.

[0182] In the embodiments provided by the present invention, it should be understood that the disclosed devices / electronic devices and methods can be implemented in other ways. For example, the device / electronic device embodiments described above are merely illustrative. For example, the division of the modules or units is merely a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0183] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of this embodiment.

[0184] In addition, the functional units in various embodiments of the present invention may be integrated into a single processing unit, each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software functional units.

[0185] If the integrated module / unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the present invention can also implement all or part of the processes in the above-mentioned method embodiments by instructing the relevant hardware through a computer program. The computer program can be stored in a computer-readable storage medium. When executed by a processor, the computer program can implement the steps of the above-mentioned method and device embodiments. The computer program includes computer program code, which can be in source code form, object code form, executable file, or some intermediate form. The computer-readable medium can include: any entity or device capable of carrying the computer program code, recording medium, USB flash drive, mobile hard drive, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signal, telecommunication signal, and software distribution medium.

[0186] The above-described embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention, and should all be included in the scope of protection of the present invention.

Claims

1. A method for measuring an angular position, characterized in that: Applicable to an angular position measurement system, the angular position measurement system comprising: A magnetic field excitation mechanism, a plurality of magnetic field sensors, and a signal processing unit; The plurality of magnetic field sensors are electrically connected to the signal processing unit; The magnetic field excitation mechanism generates a sinusoidal magnetic field of at least one complete cycle on the circumference; The plurality of magnetic field sensors are distributed in an array along the central circumference of the sinusoidal magnetic field; When the multiple magnetic field sensors respectively return magnetic field strength signals at their respective locations, the signal processing unit determines the angular position of the sinusoidal magnetic field relative to the multiple magnetic field sensors based on the number of sinusoidal wave cycles in the sinusoidal wave magnetic field and the multiple magnetic field strength signals; The magnetic field excitation mechanism includes a magnetic ring and a plurality of magnetic steels; the plurality of magnetic steels are fixedly arranged on the magnetic ring in a circumferential array, and the magnetic pole directions of the plurality of magnetic steels are alternately arranged along the axial direction of the magnetic ring; the magnetic ring is a poor conductor of magnetism; The angular position measurement method comprises: Obtaining a first standard magnetic field strength array and a second standard magnetic field strength array, wherein the first standard magnetic field strength array and the second standard magnetic field strength array are arrays constructed based on multiple standard magnetic field strength signals, and the standard magnetic field signals are magnetic field strength signals returned by the magnetic field sensors when the angle of the sinusoidal wave magnetic field relative to the multiple magnetic field sensors is at a standard angular position; constructing a first array based on the magnetic field strength signals currently returned by the multiple magnetic field sensors, and determining a first cosine value and a first sine value based on the first array, the number of sinusoidal wave cycles in the sinusoidal wave magnetic field, the first standard magnetic field strength array, and the second standard magnetic field strength array; determining the quadrant in which the relative angular position is located according to the sign of the first cosine value and the sign of the first sine value; The angular position is determined according to the standard angular position, the quadrant in which the relative angular position is located, and at least one of the first cosine value and the first sine value.

2. The angular position measurement method according to claim 1, characterized in that: The step of constructing a first array based on the magnetic field strength signals currently returned by the plurality of magnetic field sensors, and determining a first cosine value and a first sine value based on the first array, the number of sinusoidal wave cycles in the sinusoidal wave magnetic field, the first standard magnetic field strength array, and the second standard magnetic field strength array includes: Acquire magnetic field strength signals currently returned by the multiple magnetic field sensors; Arranging the magnetic field strength signals currently returned by the plurality of magnetic field sensors according to the locations of the magnetic field sensors to obtain an intermediate array; reconstructing and normalizing the sinusoidal magnetic field according to the magnetic field intensity value, the number of sinusoidal wave cycles in the sinusoidal wave magnetic field, the number of the plurality of magnetic field sensors, and the intermediate array to obtain the first array; The dot product of the first array and the first standard magnetic field strength array and the dot product of the first array and the second standard magnetic field strength array are calculated respectively to obtain the first cosine value and the first sine value.

3. The angular position measurement method according to claim 1, characterized in that: The determining of a first cosine value and a first sine value according to the first array, the number of sinusoidal wave cycles in the sinusoidal wave magnetic field, the first standard magnetic field strength array, and the second standard magnetic field strength array includes: The first cosine value is determined according to a first formula, wherein the first formula is: Where, is the first cosine value, The first array numerical values, is the number of multiple magnetic field sensors, The first standard magnetic field strength array data, is a sine function, is pi, is the number of sine wave cycles in the sinusoidal magnetic field, is the standard angular position; The first sine value is determined according to a second formula, wherein the second formula is: Where, is the first sine value, The first data, is the cosine function.

4. The angular position measurement method according to claim 1, wherein: The determining, according to the sign of the first cosine value and the sign of the first sine value, the quadrant in which the relative angular position is located includes: If the first cosine value is positive and the first sine value is positive, the relative angular position is in the first quadrant; If the first cosine value is negative and the first sine value is positive, the relative angular position is in the second quadrant; If the first cosine value is negative and the first sine value is negative, the relative angular position is in the third quadrant; If the first cosine value is positive and the first sine value is negative, the relative angular position is in the fourth quadrant.

5. The angular position measurement method according to any one of claims 1 to 4, characterized in that: The determining of the angular position according to the standard angular position, the quadrant in which the relative angular position is located, and at least one of the first cosine value and the first sine value comprises: The angular position is determined according to a third formula or a fourth formula, wherein the third formula is: Where, is the relative angular position, is the inverse cosine function, is the angular position, is the standard angular position, is the first cosine value, is the number of multiple magnetic field sensors, is the number of sine wave cycles in the sinusoidal magnetic field, For the first quadrant, For the second quadrant, For the third quadrant, The fourth quadrant, is pi; The fourth formula is: Where, is the inverse sine function, is the first sine value.

6. An angular position measuring device, characterized in that: For implementing the angular position measurement method according to any one of claims 1 to 5, the angular position measurement device comprises: a standard magnetic field strength acquisition module, configured to acquire a first standard magnetic field strength array and a second standard magnetic field strength array, wherein the first standard magnetic field strength array and the second standard magnetic field strength array are arrays constructed based on a plurality of standard magnetic field strength signals, and the standard magnetic field signals are magnetic field strength signals returned by the magnetic field sensors when the angle of the sinusoidal magnetic field relative to the plurality of magnetic field sensors is at a standard angular position; an angular position data extraction module, configured to construct a first array based on the magnetic field strength signals currently returned by the plurality of magnetic field sensors, and determine a first cosine value and a first sine value based on the first array, the number of sinusoidal wave cycles in the sinusoidal wave magnetic field, the first standard magnetic field strength array, and the second standard magnetic field strength array; a quadrant positioning module, configured to determine the quadrant in which the relative angular position is located according to the sign of the first cosine value and the sign of the first sine value; as well as, An angular position determination module is configured to determine the angular position based on the standard angular position, the quadrant where the relative angular position is located, and the first cosine value, or based on the standard angular position, the quadrant where the relative angular position is located, and the first sine value.

7. An electronic device comprising a memory and a processor, wherein the memory stores a computer program that can be run on the processor, characterized in that: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 5 are implemented.

8. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 5 are implemented.

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