Method and device for calibrating position of encoder, and storage medium

Abstract

The embodiment of the invention relates to a method and device for calibrating the position of an encoder and a storage medium. The method comprises the following steps: determining a reference zero point and a reference phase corresponding to the reference zero point and related to an A-phase signal and a B-phase signal according to the A-phase signal, the B-phase signal and a Z-phase signal from an encoder; during the valid period of the Z-phase signal, generating a zero point mark matching signal according to the valid edges about the A-phase signal and the B-phase signal, the real-time rotation direction of the encoder and the reference rotation direction when the reference zero point is determined; and calibrating a position counter about the position of the encoder according to the phase difference between the reference phase and the real-time phase of the A-phase signal and the B-phase signal corresponding to the zero mark matching signal. According to the scheme, the position of the encoder can be accurately calibrated.

Description

Technical Field

[0001] Embodiments of the present disclosure generally relate to the field of control of encoder calibration, and more particularly to a method, apparatus, and storage medium for calibrating the position of an encoder. Background Art

[0002] Due to the physical limitations of the grating and the limitations of the optical sensor, the motor encoder often loses the line during rotation, resulting in a discrepancy between the position count of the decoding unit and the actual position. Under the existing technology, the encoder introduces the Z-phase signal to facilitate the calibration of the decoding unit, but due to the non-uniform specifications of the encoders produced by various companies, the width of the Z-phase signal is inconsistent; and due to line delay and jitter problems, the Z-phase signal cannot be used to calibrate the encoder's counting position very accurately. Summary of the invention

[0003] In view of the above problems, the present disclosure provides a method, a device and a storage medium for calibrating the position of an encoder, which can accurately calibrate the position of the encoder.

[0004] According to a first aspect of the present disclosure, a method for calibrating the position of an encoder is provided. The method comprises: determining a reference zero point and a reference phase of the A-phase signal and the B-phase signal corresponding to the reference zero point according to the A-phase signal, the B-phase signal and the Z-phase signal from the encoder; generating a zero mark matching signal according to the valid edge of the A-phase signal and the B-phase signal, the real-time rotation direction of the encoder and the reference rotation direction when determining the reference zero point during the effective period of the Z-phase signal; and calibrating a position counter for the position of the encoder according to the phase difference between the real-time phase of the A-phase signal and the B-phase signal corresponding to the zero mark matching signal and the reference phase.

[0005] In some embodiments, during the valid period of the Z-phase signal, generating a zero point mark matching signal based on the valid edges of the A-phase signal and the B-phase signal, the real-time rotation direction of the encoder, and the reference rotation direction when determining the reference zero point includes: in response to determining that the real-time rotation direction is the same as the reference rotation direction, generating a zero point mark matching signal at the target valid edge of the A-phase signal and the B-phase signal, the target valid edge being the valid edge corresponding to when determining the reference zero point.

[0006] In some embodiments, during the valid period of the Z-phase signal, generating a zero point mark matching signal based on the valid edges of the A-phase signal and the B-phase signal, the real-time rotation direction of the encoder, and the reference rotation direction when determining the reference zero point also includes: in response to determining that the real-time rotation direction is opposite to the reference rotation direction, generating a zero point mark matching signal based on the matching relationship between the real-time phase corresponding to the valid edge and the reference phase, the real-time pulse width count value for the valid period of the Z-phase signal, and the pulse width of the Z-phase signal, the pulse width of the Z-phase signal being the number of overlaps between the valid period of the Z-phase signal and the valid edge.

[0007] In some embodiments, in response to determining that the real-time rotation direction is opposite to the reference rotation direction, generating a zero point mark matching signal according to the matching relationship between the real-time phase corresponding to the effective edge and the reference phase, the real-time pulse width count value for the effective period of the Z-phase signal, and the pulse width of the Z-phase signal includes: performing real-time counting for the effective period of the Z-phase signal based on the effective edge to obtain the real-time pulse width count value; and generating a zero point mark matching signal at the point where the real-time phase corresponding to the effective edge matches the reference phase during the period when the difference between the real-time pulse width count value and the pulse width of the Z-phase signal is less than or equal to a predetermined value.

[0008] In some embodiments, calibrating a position counter regarding the position of the encoder based on the phase difference between the real-time phase of the A-phase signal and the B-phase signal corresponding to the zero-point mark matching signal and the reference phase includes: determining a first reset value of the position counter regarding the position of the encoder in response to determining that the real-time rotation direction is the same as the reference rotation direction, so as to reset the position counter at the zero-point mark matching signal, and the first reset value is the phase difference; and determining a second reset value of the position counter regarding the position of the encoder in response to determining that the real-time rotation direction is opposite to the reference rotation direction, so as to reset the position counter at the zero-point mark matching signal, and the second reset value is the difference between a predetermined position count maximum value and the phase difference.

[0009] In some embodiments, determining the reference zero point based on the A-phase signal, B-phase signal and Z-phase signal from the encoder includes: determining the reference zero point corresponding to the target valid edge of the A-phase signal and the B-phase signal during the valid period of the Z-phase signal, the target valid edge is the first valid edge during the valid period of the Z-phase signal, and the valid edge is any one of the following: the transition edge of the A-phase signal; and the transition edge of the B-phase signal.

[0010] In some embodiments, the method further includes: determining the phase information corresponding to each of the valid edges in sequence to determine the phase difference; and determining the real-time zero point of the encoder according to the calibrated position counter.

[0011] According to a second aspect of the present disclosure, an electronic device is provided. The electronic device includes: at least one processor; and a memory connected to the at least one processor in communication; the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can perform the method of the first aspect of the present disclosure.

[0012] According to a third aspect of the present disclosure, a computer-readable storage medium is provided. The computer-readable storage medium stores a computer program, and when the computer program is executed by a machine, the method according to the first aspect of the present disclosure is implemented.

[0013] According to a fourth aspect of the present disclosure, there is provided a computer program product, which is tangibly stored on a non-transitory computer-readable medium and comprises machine-executable instructions, which when executed cause a machine to perform the steps in the method according to the first aspect of the present disclosure.

[0014] According to the technical solution disclosed in the present invention, after determining the reference zero point and the reference phase corresponding to the reference zero point, during the valid period of the Z phase signal, a zero point mark matching signal is generated according to the valid edges of the A phase signal and the B phase signal, the real-time rotation direction of the encoder, and the reference rotation direction when the reference zero point is determined; and according to the phase difference between the real-time phase of the A phase signal and the B phase signal corresponding to the zero point mark matching signal and the reference phase, the position counter related to the position of the encoder is calibrated, so that the position of the encoder can be accurately calibrated.

[0015] 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

[0016] The above and other features, advantages and aspects of the embodiments of the present disclosure will become more apparent with reference to the following detailed description in conjunction with the accompanying drawings. In the accompanying drawings, the same or similar reference numerals represent the same or similar elements.

[0017] Figure 1 A schematic diagram of an encoder according to an embodiment of the present disclosure is shown.

[0018] Figure 2 A schematic diagram showing several states of rotation of the encoder according to an embodiment of the present disclosure.

[0019] Figure 3 A schematic diagram of the waveforms of the A-phase signal, the B-phase signal and the Z-phase signal of an embodiment of the present disclosure is shown.

[0020] Figure 4A schematic diagram of an electronic device that can be used to implement the method for calibrating the position of an encoder according to an embodiment of the present disclosure is shown.

[0021] Figure 5 A flow chart of a method for calibrating the position of an encoder according to an embodiment of the present disclosure is shown.

[0022] Figure 6 A schematic diagram showing the phases of an A-phase signal and a B-phase signal according to an embodiment of the present disclosure is shown.

[0023] Figure 7 A schematic diagram showing the phases of an A-phase signal and a B-phase signal according to an embodiment of the present disclosure is shown.

[0024] Figure 8 A waveform diagram corresponding to a method for calibrating the position of an encoder executed by an electronic device according to an embodiment of the present disclosure is shown.

[0025] Fig. 9 A schematic block diagram of an example electronic device that can be used to implement a method for calibrating the position of an encoder according to an embodiment of the present disclosure is shown. DETAILED DESCRIPTION

[0026] 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 and spirit of the present disclosure. Similarly, for the sake of clarity and conciseness, descriptions of well-known functions and structures are omitted in the following description.

[0027] As used herein, the term "including" and its variations mean open inclusion, i.e., "including but not limited to". Unless otherwise stated, the term "or" means "and / or". The term "based on" means "based at least in part on". The terms "an example embodiment" and "an embodiment" mean "at least one example embodiment". The term "another embodiment" means "at least one additional embodiment". The terms "first", "second", etc. may refer to different or the same objects. Other explicit and implicit definitions may also be included below.

[0028] As mentioned above, under the existing technology, the encoder introduces a Z-phase signal to facilitate calibration of the decoding unit. However, due to the non-uniform specifications of encoders produced by various companies, the width of the Z-phase signal is inconsistent. In addition, due to line delay and jitter problems, the Z-phase signal cannot be used to calibrate the encoder's counting position very accurately.

[0029] In order to at least partially solve one or more of the above problems and other potential problems, the exemplary embodiments of the present disclosure propose a method, device and storage medium for calibrating the position of an encoder. In this scheme, after determining the reference zero point and the reference phase corresponding to the reference zero point, during the effective period of the Z phase signal, a zero mark matching signal is generated according to the effective edge of the A phase signal and the B phase signal, the real-time rotation direction of the encoder and the reference rotation direction when the reference zero point is determined; and according to the phase difference between the real-time phase of the A phase signal and the B phase signal corresponding to the zero mark matching signal and the reference phase, the position counter of the position of the encoder is calibrated, and the position of the encoder can be accurately calibrated.

[0030] Figure 1 A schematic diagram of an encoder 100 of an embodiment of the present disclosure is shown. The encoder 100, for example, includes a code disk 102 and a plurality of gratings disposed on the code disk 102. The plurality of gratings, for example, include an A-phase grating 104, a B-phase grating 106, and a Z-phase grating 108. For ease of explanation, the position of the sensor is also indicated by a line 110 in the figure. It should be understood that the sensor is used to detect the A-phase grating 104, the B-phase grating 106, and the Z-phase grating 108 in order to generate corresponding A-phase signals EQEP_A, B-phase signals EQEP_B, and Z-phase signals EQEP_Z. Taking the A-phase signal EQEP_A as an example, when the sensor does not detect the A-phase grating 104 (for example, the line 110 is aligned with the outside of the A-phase grating 104), the A-phase signal EQEP_A generated at this time is, for example, a low level. When the sensor detects the A-phase grating 104 (for example, the line 110 is aligned with the inside of the A-phase grating 104), the A-phase signal EQEP_A generated at this time is, for example, a high level. Therefore, the rising edge and the falling edge of the A-phase signal EQEP_A are generated corresponding to the edge of the A-phase grating 104. It should be understood that in some embodiments, the polarity of the generated A-phase signal EQEP_A may be opposite to the above situation. Regarding the B-phase signal EQEP_B and the Z-phase signal EQEP_Z, reference can be made to the A-phase signal EQEP_A, which will not be repeated here. The A-phase signal EQEP_A, the B-phase signal EQEP_B and the Z-phase signal EQEP_Z generated by the encoder 100 are sent to the control unit, for example, and the control unit determines the position corresponding to the encoder according to the A-phase signal EQEP_A, the B-phase signal EQEP_B and the Z-phase signal EQEP_Z, so as to control the motor.

[0031] Figure 2 A schematic diagram showing several states of rotation of the encoder according to an embodiment of the present disclosure.

[0032] There are 8 states in total, from state 1 to state 8. As a simplified illustration, the encoder only illustrates the code disk 102 and the Z-phase grating 108. It should be understood that the encoder rotation state is not limited to the 8 states shown in the figure.

[0033] Figure 3 The waveform diagram of the A-phase signal, the B-phase signal and the Z-phase signal of the embodiment of the present disclosure is shown. Among them, EQEP_ZS represents the desired standard Z-phase signal. However, due to the influence of factors such as signal jitter and line delay, the Z-phase signal actually received by the control unit may sometimes be as shown in EQEP_Z1, or sometimes as shown in EQEP_Z2. For example, near the time T1, the generation of the rising edge of EQEP_Z1 is ahead of the rising edge of the standard Z-phase signal EQEP_ZS; and, near the time T2, the generation of the falling edge of EQEP_Z1 is ahead of the falling edge of the standard Z-phase signal EQEP_ZS. For another example, near the time T1, the generation of the rising edge of EQEP_Z2 lags behind the rising edge of the standard Z-phase signal EQEP_ZS; and, near the time T2, the generation of the falling edge of EQEP_Z1 lags behind the falling edge of the standard Z-phase signal EQEP_ZS. It should be understood that these advance or lag conditions will affect the calibration of the encoder position.

[0034] Figure 4 A schematic diagram of an electronic device 400 that can be used to implement the method for calibrating the position of an encoder according to an embodiment of the present disclosure is shown. The electronic device 400 receives the A-phase signal EQEP_A, the B-phase signal EQEP_B, and the Z-phase signal EQEP_Z from the encoder 100, calibrates the position counter regarding the position of the encoder, and sends the position count value of the position counter regarding the position of the encoder after the calibration to the control unit 404. The control unit 404 controls the motor 402 based on the position count value of the position counter regarding the position of the encoder after the calibration.

[0035] Figure 5 1 is a flow chart showing a method 500 for calibrating the position of an encoder according to an embodiment of the present disclosure. The method 500 may be performed as follows: Figure 4 The electronic device 400 shown in the figure may also be used in Fig. 9 The method 500 is executed at the electronic device 900 shown. It should be understood that the method 500 may further include additional steps not shown and / or may omit the steps shown, and the scope of the present disclosure is not limited in this respect.

[0036] At step 502 , a reference zero point and a reference phase of the A-phase signal and the B-phase signal corresponding to the reference zero point are determined according to the A-phase signal, the B-phase signal and the Z-phase signal from the encoder.

[0037] At step 504 , during the valid period of the Z-phase signal, a zero mark matching signal is generated according to the valid edges of the A-phase signal and the B-phase signal, the real-time rotation direction of the encoder, and the reference rotation direction when determining the reference zero point.

[0038] At step 506 , a position counter related to the position of the encoder is calibrated according to the phase difference between the real-time phase of the A-phase signal and the B-phase signal corresponding to the zero mark matching signal and the reference phase.

[0039] In some embodiments, at step 502, the target effective edge of the A-phase signal and the B-phase signal during the effective period of the Z-phase signal is used as the reference zero point, and the phase (or "state") of the A-phase signal and the B-phase signal corresponding to the position is used as the reference phase. In some embodiments, the target effective edge is, for example, the first effective edge of the A-phase signal and the B-phase signal during the effective period of the Z-phase signal. It should be understood that the target effective edge can also be the second effective edge or the third effective edge of the A-phase signal and the B-phase signal during the effective period of the Z-phase signal.

[0040] Figure 6 A schematic diagram of the phase of the A-phase signal and the B-phase signal of an embodiment of the present disclosure is shown. For example, the figure shows the A-phase signal and the B-phase signal generated by the encoder 100 rotating in the positive direction. At time T0, the A-phase signal EQEP_A jumps from a low level to a high level, that is, a rising edge, so the phase (or "state") SA of the A-phase signal EQEP_A is represented by "↑". And, at time T0, the B-phase signal EQEP_B is a low level, so the phase of the B-phase signal EQEP_B is represented by "0". Correspondingly, at time T0, the phase SAB of the A-phase signal and the B-phase signal is represented by "↑0". And, during the period from time T0 to time T1, the phase SAB of the A-phase signal and the B-phase signal is "↑0".

[0041] At time T1, the A-phase signal EQEP_A is at a high level, and the phase SA of the A-phase signal EQEP_A is represented by "1". Also, at time T1, the B-phase signal EQEP_B jumps from a low level to a high level, i.e., a rising edge, so the phase (or "state") SB of the B-phase signal EQEP_B is represented by "↑". Accordingly, at time T1, the phase SAB of the A-phase signal and the B-phase signal is represented by "1↑". Also, during the period from time T1 to time T2, the phase SAB of the A-phase signal and the B-phase signal is "1↑".

[0042] At time T2, the A-phase signal EQEP_A changes from a high level to a low level, i.e., a falling edge, and therefore, the phase (or "state") SA of the A-phase signal EQEP_A is represented by "↓". Also, at time T2, the B-phase signal EQEP_B is at a high level, and therefore, the phase of the B-phase signal EQEP_B is represented by "1". Accordingly, at time T1, the phase SAB of the A-phase signal and the B-phase signal is represented by "↓1". Also, during the period from time T2 to time T3, the phase SAB of the A-phase signal and the B-phase signal is "↓1".

[0043] At time T3, the A-phase signal EQEP_A is at a low level, so the phase SA of the A-phase signal EQEP_A is represented by "0". Also, at time T3, the B-phase signal EQEP_B changes from a high level to a low level, so the phase of the B-phase signal EQEP_B is represented by "↓". Accordingly, at time T3, the phase SAB of the A-phase signal and the B-phase signal is represented by "0↓". Also, during the period from time T3 to time T4, the phase SAB of the A-phase signal and the B-phase signal is "0↓".

[0044] It should be understood that if the encoder 100 continues to rotate in the positive direction, the same A-phase signal and B-phase signal as those at time T0 will be generated at time T4. Accordingly, in subsequent moments, the phase SAB of the A-phase signal and the B-phase signal will also cycle back and forth in the aforementioned order.

[0045] It is worth noting that any transition edge of any of the A-phase signal and the B-phase signal belongs to the valid edge of the A-phase signal and the B-phase signal. For example, at time T0, the rising edge of the A-phase signal EQEP_A occurs, which belongs to the valid edge of the A-phase signal and the B-phase signal; at time T1, the rising edge of the B-phase signal EQEP_B occurs, which belongs to the valid edge of the A-phase signal and the B-phase signal; at time T3, the falling edge of the A-phase signal EQEP_A occurs, which belongs to the valid edge of the A-phase signal and the B-phase signal; at time T3, the falling edge of the B-phase signal EQEP_B occurs, which belongs to the valid edge of the A-phase signal and the B-phase signal.

[0046] Therefore, the time from T0 to T4 can be regarded as one cycle. It should be understood that within the same cycle, the phase difference between the A-phase signal and the B-phase signal can be determined based on the phase SAB determined at two moments, and the phase difference corresponds to the number of valid edges of the A-phase signal and the B-phase signal experienced between the two moments. For example, the phase difference between the phase SAB "1↑" of the A-phase signal and the B-phase signal corresponding to the moment T1 and the phase SAB "↑0" of the A-phase signal and the B-phase signal corresponding to the moment T0 is 1, so the number of valid edges of the A-phase signal and the B-phase signal experienced between the moment T1 and the moment T0 is 1.

[0047] Figure 7 A schematic diagram of the phase of the A-phase signal and the B-phase signal of an embodiment of the present disclosure is shown. For example, the figure shows the A-phase signal and the B-phase signal generated by the encoder 100 rotating in the reverse direction. At time T0, the A-phase signal EQEP_A is at a low level, so the phase SA of the A-phase signal EQEP_A is represented by "0". And, at time T0, the B-phase signal EQEP_B jumps from a low level to a high level, that is, a rising edge, so the phase SB of the B-phase signal EQEP_B is represented by "↑". Correspondingly, at time T0, the phase SAB of the A-phase signal and the B-phase signal is represented by "0↑". And, during the period from time T0 to time T1, the phase SAB of the A-phase signal and the B-phase signal is "0↑".

[0048] At time T1, the A-phase signal EQEP_A changes from a low level to a high level, i.e., a rising edge, and therefore, the phase SA of the A-phase signal EQEP_A is represented by "↑". Also, at time T1, the B-phase signal EQEP_B is at a high level, and the phase SB of the B-phase signal EQEP_B is represented by "1". Accordingly, at time T1, the phase SAB of the A-phase signal and the B-phase signal is represented by "↑1". Also, during the period from time T1 to time T2, the phase SAB of the A-phase signal and the B-phase signal is "↑1".

[0049] At time T2, the A-phase signal EQEP_A is at a high level, so the phase of the A-phase signal EQEP_A is represented by "1". Also, at time T2, the B-phase signal EQEP_B changes from a high level to a low level, i.e., a falling edge, so the phase SB of the B-phase signal EQEP_B is represented by "↓". Accordingly, at time T1, the phase SAB of the A-phase signal and the B-phase signal is represented by "1↓". Also, during the period from time T2 to time T3, the phase SAB of the A-phase signal and the B-phase signal is "1↓".

[0050] At time T3, the A-phase signal EQEP_A changes from a high level to a low level, so the phase of the A-phase signal EQEP_A is represented by "↓". Also, at time T3, the B-phase signal EQEP_B is at a low level, so the phase SB of the B-phase signal EQEP_B is represented by "0". Accordingly, at time T3, the phase SAB of the A-phase signal and the B-phase signal is represented by "↓0". Also, during the period from time T3 to time T4, the phase SAB of the A-phase signal and the B-phase signal is "↓0".

[0051] It should be understood that if the encoder 100 continues to rotate in the reverse direction, the same A-phase signal and B-phase signal as those at time T0 will be generated at time T4. Accordingly, in subsequent moments, the phase SAB of the A-phase signal and the B-phase signal will also cycle back and forth in the aforementioned order.

[0052] Figure 8 The waveform diagram corresponding to the method for calibrating the position of the encoder performed by the electronic device of the embodiment of the present disclosure is shown. Among them, clk represents the working clock (high-frequency clock) signal of the electronic device 400. The positive pulse of the QEVT signal represents the capture of the valid edge of the A-phase signal and the B-phase signal. QDIR is used to represent the rotation direction of the encoder 100, wherein when QDIR is at a high level, it represents that the rotation direction of the encoder 100 is in the positive direction; when QDIR is at a low level, it represents that the rotation direction of the encoder 100 is in the reverse direction. Regarding the signal ZHIT, in the process of determining the reference zero point, its valid pulse (such as a positive pulse) represents that the corresponding position is the reference zero point, and after determining the reference zero point, its valid pulse (such as a positive pulse) represents the zero mark matching signal. ZWCNT represents the real-time pulse width count value. QPOSCNT represents the count value of the position counter. SAB represents the phase of the A-phase signal and the B-phase signal. QEPSTS.ZW represents the pulse width of the Z-phase signal. QEPSTS.FZDIR represents the reference rotation direction, that is, the rotation direction of the encoder 100 when the reference zero point is determined. QEPSTS.FZDIR is high, indicating that the reference rotation direction is positive; QEPSTS.FZDIR is low, indicating that the reference rotation direction is negative. QEPSTS.FZDET indicates the flag for determining the reference zero point. QEPSTS.FZDET is high, indicating that the reference zero point has been determined. When QEPSTS.FZDET is high, the position counter of the encoder position can be calibrated based on the determined reference zero point.

[0053] At time 804, due to the influence of factors such as signal jitter and line delay, there is a deviation between the Z-phase signal (indicated by a solid line) actually received by the control unit and the standard Z-phase signal (indicated by a dotted line). Similarly, at time 802, due to the influence of factors such as signal jitter and line delay, there is a deviation between the Z-phase signal (indicated by a solid line) actually received by the control unit and the standard Z-phase signal (indicated by a dotted line).

[0054] It is worth noting that the electronic device 400 uses the high-frequency clock clk as the working clock. For example, the electronic device 400 samples the A-phase signal EQEP_A, the B-phase signal EQEP_B and the Z-phase signal EQEP_Z based on the high-frequency clock clk to determine the level states and transition edges of the A-phase signal EQEP_A, the B-phase signal EQEP_B and the Z-phase signal EQEP_Z.

[0055] In the figure, the positive pulse representation of QEVT is based on the high-frequency clock clk to sample the A-phase signal EQEP_A and the B-phase signal EQEP_B, and capture the valid edges of the A-phase signal and the B-phase signal. In some embodiments, the pulse QEVT1 is taken as the first valid edge of the A-phase signal and the B-phase signal during the period when the Z-phase signal is valid (for example, when the Z-phase signal is in a high-level state, it is considered to be in a valid state). Among them, the rising edge of the previous pulse of the pulse QEVT1 is aligned with the rising edge of the Z-phase signal, so the pulse is not taken as the first valid edge of the A-phase signal and the B-phase signal during the period when the Z-phase signal is valid.

[0056] Therefore, corresponding to the pulse QEVT1, a positive pulse ZHIT1 is generated in the ZHIT signal, which is used to indicate that the reference zero point is determined. In addition, the reference phase corresponding to the reference zero point (positive pulse ZHIT1) is "↓1".

[0057] In some embodiments, the reference rotation direction of the encoder 100 is further determined when determining the reference zero point. Figure 6 as well as Figure 7 The change pattern of the phase of the A-phase signal and the B-phase signal is associated with the rotation direction of the encoder 100. Therefore, in some embodiments, the rotation direction of the encoder 100 can be determined based on the change of the phase of the A-phase signal and the B-phase signal corresponding to two adjacent valid edges of the A-phase signal and the B-phase signal.

[0058] At step 504 , during the valid period of the Z-phase signal, a zero mark matching signal is generated according to the valid edges of the A-phase signal and the B-phase signal, the real-time rotation direction of the encoder, and the reference rotation direction when determining the reference zero point.

[0059] In some embodiments, step 504 includes: in response to determining that the real-time rotation direction is the same as the reference rotation direction, generating a zero point mark matching signal at the target effective edge of the A-phase signal and the B-phase signal, the target effective edge being the effective edge corresponding to when determining the reference zero point.

[0060] It should be understood that the real-time rotation direction may also be determined based on the phase changes of the A-phase signal and the B-phase signal corresponding to two adjacent valid edges of the A-phase signal and the B-phase signal.

[0061] Among them, the pulse width of the Z-phase signal can be determined based on the effective edge of the A-phase signal and the B-phase signal during the rotation of the encoder 100 in the same direction, and the effective period of the Z-phase signal is counted. It is worth noting that the pulse width of the Z-phase signal is determined, for example, in the process of determining the reference zero point in step 502. For example, after determining the reference zero point in the positive direction, if the encoder 100 continues to rotate in the positive direction, the pulse width counter is used to continue counting in the positive direction based on the effective edge of the A-phase signal and the B-phase signal (that is, each time the effective edge of the A-phase signal and the B-phase signal occurs, the count value increases by 1). Until the complete count in the positive direction is completed for the effective period of the Z-phase signal. It should be understood that if the encoder 100 rotates in the reverse direction, the pulse width counter is used to continue counting in the reverse direction based on the effective edge of the A-phase signal and the B-phase signal (that is, each time the effective edge of the A-phase signal and the B-phase signal occurs, the count value decreases by 1).

[0062] It is worth noting that if Figure 8 As shown, at the pulse ZHIT1, the reference zero point has actually been determined, and as an example only, QEPSTS.FZDET is set to a high level after determining the pulse width of the Z-phase signal. It should be understood that in some embodiments, QEPSTS.FZDET can also be set to a high level after the pulse ZHIT1.

[0063] During the effective period of the Z-phase signal, according to the effective edges of the A-phase signal and the B-phase signal, the real-time rotation direction of the encoder, and the reference rotation direction when the reference zero point is determined, in the process of generating the zero mark matching signal, if the real-time rotation direction is the same as the reference rotation direction, the zero mark matching signal is generated at the target effective edge of the A-phase signal and the B-phase signal. For example, the zero mark matching signal is generated at the first effective edge of the A-phase signal and the B-phase signal during the effective period of the Z-phase signal (i.e., the effective edge corresponding to the determination of the reference zero point).

[0064] For example, during PE1, the encoder 100 rotates in the positive direction. At time 804, due to the influence of factors such as signal jitter and line delay, there is a deviation between the Z-phase signal (indicated by a solid line) actually received by the control unit and the standard Z-phase signal (indicated by a dotted line). Therefore, the positive pulse QEVT2 indicates that the target valid edge of the A-phase signal and the B-phase signal is captured, and thus, the zero mark matching signal ZHIT2 is generated.

[0065] Accordingly, at step 506, in response to determining that the real-time rotation direction is the same as the reference rotation direction, a first reset value of the position counter relative to the position of the encoder is determined so as to reset the position counter at the zero mark matching signal. When the phase difference is a negative number, the first reset value is the sum of a predetermined position count maximum value, 1, and the above phase difference. When the phase difference is a non-negative number, the first reset value is the above phase difference.

[0066] For example, at the positive pulse QEVT2, the real-time phase of the A-phase signal and the B-phase signal corresponding to the zero mark matching signal QEVT2 is determined to be "1↑". And the real-time rotation direction is determined to be the positive direction, which is the same as the reference rotation direction (positive direction). The phase difference between the above real-time phase ("1↑") and the reference phase ("↓1") is "-1". That is, the target effective edge of the A-phase signal and the B-phase signal corresponding to the zero mark matching signal ZHIT2 is "one count pulse" ahead of the target effective edge of the A-phase signal and the B-phase signal corresponding to the positive pulse ZHIT1 (i.e., the reference zero point) in terms of phase. In other words, the target effective edge of the A-phase signal and the B-phase signal corresponding to the zero mark matching signal ZHIT2 is "one effective edge" ahead of the target effective edge of the A-phase signal and the B-phase signal corresponding to the positive pulse ZHIT1 (i.e., the reference zero point) in terms of phase. Therefore, at the positive pulse QEVT2, the position counter of the encoder position is reset to "125". The predetermined maximum position count value of the position counter of the encoder position is "125".

[0067] It is worth noting that Figure 8For example, due to factors such as encoder failure, the A-phase signal EQEP_A / B-phase signal EQEP_ABI has fewer input pulses, resulting in the real-time count value QPOSCNT of the position counter being less counted, causing an error in the position counter of the encoder position. For example, before the positive pulse ZHIT2 appears, QPOSCNT only counts to 122. Due to the appearance of the positive pulse ZHIT2 (i.e., the zero mark matching signal), the count value of the position counter of the encoder position is reset to a reasonable value, and the position counter of the encoder position is calibrated to correct the above error. It should be understood that during the forward rotation of the encoder 100, the position counter of the encoder position counts positively.

[0068] It should be understood that if the phase difference between the real-time phase and the reference phase is "1", it means that the target effective edge of the A-phase signal and the B-phase signal corresponding to the zero mark matching signal ZHIT2 lags behind the target effective edge of the A-phase signal and the B-phase signal corresponding to the positive pulse ZHIT1 (i.e., the reference zero point) by "one count pulse" in terms of phase. In other words, the target effective edge of the A-phase signal and the B-phase signal corresponding to the zero mark matching signal ZHIT2 lags behind the target effective edge of the A-phase signal and the B-phase signal corresponding to the positive pulse ZHIT1 (i.e., the reference zero point) by "one effective edge" in terms of phase. Accordingly, the first reset value is "1".

[0069] For another example, if the phase difference between the real-time phase and the reference phase is "0", that is, the real-time phase at the zero mark matching signal matches the reference zero point at the reference zero point, the position counter of the encoder position is reset to "0".

[0070] In some embodiments, step 504 also includes: in response to determining that the real-time rotation direction is opposite to the reference rotation direction, generating a zero mark matching signal according to the matching relationship between the real-time phase corresponding to the effective edge and the reference phase, the real-time pulse width count value for the effective period of the Z-phase signal, and the pulse width of the Z-phase signal, wherein the pulse width of the Z-phase signal is the number of overlaps between the effective period of the Z-phase signal and the effective edge.

[0071] During the valid period of the Z-phase signal, a zero point mark matching signal is generated based on the valid edges of the A-phase signal and the B-phase signal, the real-time rotation direction of the encoder, and the reference rotation direction when determining the reference zero point. If the real-time rotation direction is opposite to the reference rotation direction, a zero point mark matching signal is generated based on the matching relationship between the real-time phase corresponding to the above-mentioned valid edge and the above-mentioned reference phase, the real-time pulse width count value during the valid period of the Z-phase signal, and the pulse width of the Z-phase signal.

[0072] Specifically, the process includes: performing real-time counting on the effective period of the Z-phase signal based on the above-mentioned effective edge to obtain a real-time pulse width count value; and generating a zero point mark matching signal at the point where the real-time phase corresponding to the effective edge matches the reference phase during a period when the difference between the real-time pulse width count value and the pulse width of the Z-phase signal is less than or equal to a predetermined value.

[0073] For example, QDIR shown in the figure is used to represent the rotation direction of the encoder 100, wherein when QDIR is at a high level, it represents that the rotation direction of the encoder 100 is the positive direction; when QDIR is at a low level, it represents that the rotation direction of the encoder 100 is the reverse direction. ZWCNT shown in the figure represents the real-time pulse width count value. The above-mentioned predetermined value is, for example, 2. Taking the figure as an example, the pulse width of the Z-phase signal is, for example, "2".

[0074] For example, during PE2, the encoder 100 rotates in the opposite direction. At time 802, due to the influence of factors such as signal jitter and line delay, there is a deviation between the Z-phase signal (indicated by a solid line) actually received by the control unit and the standard Z-phase signal (indicated by a dotted line). During the effective period of the Z-phase signal, the pulse width counter is used to count the effective period of the Z-phase signal based on the effective edges of the A-phase signal and the B-phase signal, so as to obtain the real-time pulse width count value QPOSCNT of the effective period of the Z-phase signal. During the period when the real-time pulse width count value QPOSCNT is "0", "1", "2", that is, during the period when the difference between the real-time pulse width count value and the pulse width of the Z-phase signal is less than or equal to a predetermined value, at each effective edge, it is determined whether the corresponding real-time phase matches the reference phase, and a zero mark matching signal is generated at the point where the real-time phase corresponding to the effective edge matches the reference phase. For example, at the positive pulse QEVT3, the real-time phase "1↑" corresponding to the effective edge of the corresponding A-phase signal and the B-phase signal matches the reference phase "1↑", and therefore, a zero mark matching signal ZHIT3 is generated there.

[0075] Accordingly, at step 506, in response to determining that the above-mentioned real-time rotation direction is opposite to the reference rotation direction, a second reset value of the position counter relative to the position of the encoder is determined so as to reset the position counter at the zero point mark matching signal, and the second reset value is the difference between the predetermined position count maximum value and the above-mentioned phase difference.

[0076] Taking the maximum value of the predetermined position count as "125" as an example, the real-time phase corresponding to the zero point mark matching signal ZHIT3 is the same as the reference phase (i.e., matched), so the phase difference between the two is 0. Correspondingly, the second reset value is "125", which is the difference between the maximum value of the predetermined position count and the above-mentioned phase difference.

[0077] It is worth noting that Figure 8For example, due to factors such as encoder failure, the A-phase signal EQEP_A / B-phase signal EQEP_ABI has fewer input pulses, resulting in the real-time count value QPOSCNT of the position counter being less than some numbers, causing an error in the position counter regarding the position of the encoder. For example, before the positive pulse ZHIT3 appears, QPOSCNT only counts to 7 and has not yet decreased to 0. Due to the appearance of the positive pulse ZHIT3 (i.e., the zero mark matching signal), the count value of the position counter regarding the position of the encoder is reset to a reasonable value, the position counter regarding the position of the encoder is calibrated, and the above error is corrected. It should be understood that during the reverse rotation of the encoder 100, the position counter regarding the position of the encoder counts in reverse.

[0078] In some embodiments, for the scenario where the pulse width of the Z-phase signal is 0 or 1, at step 504, after the rising edge of the Z-phase signal (i.e., the transition edge corresponding to the transition of the Z-phase signal from the invalid state to the valid state), at the first valid edge of the A-phase signal and the B-phase signal (i.e., the target valid edge of the A-phase signal and the B-phase signal), the real-time rotation direction of the encoder is determined. If the real-time rotation direction is the same as the reference rotation direction, a zero mark matching signal is generated at the valid edge of the A-phase signal and the B-phase signal; if the real-time rotation direction is opposite to the reference rotation direction, no zero mark matching signal is generated.

[0079] It should be understood that the technical solution of the embodiment of the present disclosure can support a very wide range of pulse widths of the Z-phase signal of the encoder 100, for example, a pulse width range of 0 to 29, which can be adapted to most encoders. In addition, the technical solution has a strong ability to resist line delay and jitter, and can accurately calibrate the position of the encoder. Moreover, the technical solution can support various motion states of the encoder.

[0080] Fig. 9 A schematic block diagram of an example electronic device 900 of a method for calibrating the position of an encoder that can be used to implement an embodiment of the present disclosure is shown. As shown, the electronic device 900 includes a central processing unit (i.e., CPU 901), which can perform various appropriate actions and processes according to computer program instructions stored in a read-only memory (i.e., ROM 902) or loaded from a storage unit 908 into a random access memory (i.e., RAM 903). In RAM 903, various programs and data required for the operation of the electronic device 900 can also be stored. CPU 901, ROM 902, and RAM 903 are connected to each other via bus 904. An input / output interface (i.e., I / O interface 905) is also connected to bus 904.

[0081] Multiple components in the electronic device 900 are connected to the I / O interface 905, including: an input unit 906, such as a keyboard, a mouse, a microphone, etc.; an output unit 907, such as various types of displays, speakers, etc.; a storage unit 908, such as a disk, an optical disk, etc.; and a communication unit 909, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit 909 allows the electronic device 900 to exchange information / data with other devices through a computer network such as the Internet and / or various telecommunication networks.

[0082] The various processes and processing described above, such as method 500, may be executed by CPU 901. For example, in some embodiments, method 500 may be implemented as a computer software program, which is tangibly contained in a machine-readable medium, such as storage unit 908. In some embodiments, part or all of the computer program may be loaded and / or installed on electronic device 900 via ROM 902 and / or communication unit 909. When the computer program is loaded into RAM 903 and executed by CPU 901, one or more actions of method 500 described above may be performed.

[0083] The present disclosure relates to methods, apparatuses, systems, electronic devices, computer-readable storage media and / or computer program products. The computer program products may include computer-readable program instructions for executing various aspects of the present disclosure.

[0084] In some embodiments, the method 500 described above may be implemented as a computer program product. The computer program product may include a computer-readable storage medium carrying computer-readable program instructions for executing various aspects of the present disclosure.

[0085] A computer-readable storage medium may be a tangible device that can hold and store instructions used by an instruction execution device. A computer-readable storage medium may be, for example, but not limited to, an electrical storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any suitable combination of the foregoing. More specific examples of computer-readable storage media (a non-exhaustive list) include: a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), a static random access memory (SRAM), a portable compact disk read-only memory (CD-ROM), a digital versatile disk (DVD), a memory stick, a floppy disk, a mechanical encoding device, such as a punch card or a raised structure in a groove on which instructions are stored, and any suitable combination of the foregoing. As used herein, a computer-readable storage medium is not to be interpreted as a transient signal per se, such as a radio wave or other freely propagating electromagnetic wave, an electromagnetic wave propagating through a waveguide or other transmission medium (e.g., a light pulse through a fiber optic cable), or an electrical signal transmitted through a wire.

[0086] The computer-readable program instructions described herein can be downloaded from a computer-readable storage medium to each computing / processing device, or downloaded to an external computer or external storage device via a network, such as the Internet, a local area network, a wide area network, and / or a wireless network. The network may include copper transmission cables, optical fiber transmission, wireless transmission, routers, firewalls, switches, gateway computers, and / or edge computing devices. The network adapter card or network interface in each computing / processing device receives the computer-readable program instructions from the network and forwards the computer-readable program instructions for storage in a computer-readable storage medium in each computing / processing device.

[0087] The computer program instructions for performing the operation of the present disclosure may be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine-related instructions, microcode, firmware instructions, state setting data, or source code or object code written in any combination of one or more programming languages, including object-oriented programming languages, such as Smalltalk, C++, etc., and conventional procedural programming languages, such as "C" language or similar programming languages. Computer-readable program instructions may be executed entirely on a user's computer, partially on a user's computer, as an independent software package, partially on a user's computer, partially on a remote computer, or completely on a remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer via any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., using an Internet service provider to connect via the Internet). In some embodiments, an electronic circuit, such as a programmable logic circuit, a field programmable gate array (FPGA), or a programmable logic array (PLA), may be customized by utilizing the state information of the computer-readable program instructions, and the electronic circuit may execute the computer-readable program instructions, thereby realizing various aspects of the present disclosure.

[0088] Various aspects of the present disclosure are described herein with reference to the flowcharts and / or block diagrams of the methods, devices (systems) and computer program products according to the embodiments of the present disclosure. It should be understood that each box in the flowchart and / or block diagram and the combination of each box in the flowchart and / or block diagram can be implemented by computer-readable program instructions.

[0089] These computer-readable program instructions can be provided to a processing unit of a general-purpose computer, a special-purpose computer, or other programmable data processing device, thereby producing a machine, so that when these instructions are executed by the processing unit of the computer or other programmable data processing device, a device that implements the functions / actions specified in one or more boxes in the flowchart and / or block diagram is generated. These computer-readable program instructions can also be stored in a computer-readable storage medium, and these instructions cause the computer, programmable data processing device, and / or other equipment to work in a specific manner, so that the computer-readable medium storing the instructions includes a manufactured product, which includes instructions for implementing various aspects of the functions / actions specified in one or more boxes in the flowchart and / or block diagram.

[0090] Computer-readable program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other device so that a series of operating steps are performed on the computer, other programmable data processing apparatus, or other device to produce a computer-implemented process, thereby causing the instructions executed on the computer, other programmable data processing apparatus, or other device to implement the functions / actions specified in one or more boxes in the flowchart and / or block diagram.

[0091] The flow chart and block diagram in the accompanying drawings show the possible architecture, function and operation of the system, method and computer program product according to multiple embodiments of the present disclosure. In this regard, each square box in the flow chart or block diagram can represent a part of a module, program segment or instruction, and a part of a module, program segment or instruction includes one or more executable instructions for realizing the specified logical function. In some alternative implementations, the function marked in the square box can also occur in a sequence different from that marked in the accompanying drawings. For example, two continuous square boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each square box in the block diagram and / or flow chart, and the combination of the square boxes in the block diagram and / or flow chart can be implemented with a dedicated hardware-based system that performs the specified function or action, or can be implemented with a combination of special hardware and computer instructions.

[0092] The embodiments of the present disclosure have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The selection of terms used herein is intended to best explain the principles of the embodiments, practical applications, or technical improvements in the market, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein.

[0093] The above are only optional embodiments of the present disclosure and are not intended to limit the present disclosure. For those skilled in the art, the present disclosure may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present disclosure shall be included in the protection scope of the present disclosure.

Claims

1. A method for calibrating the position of an encoder, characterized in that include: Determine a reference zero point and a reference phase of the A phase signal and the B phase signal corresponding to the reference zero point according to the A phase signal, the B phase signal and the Z phase signal from the encoder; During the effective period of the Z phase signal, a zero mark matching signal is generated according to the effective edges of the A phase signal and the B phase signal, the real-time rotation direction of the encoder, and the reference rotation direction when determining the reference zero point; as well as The position counter for the position of the encoder is calibrated according to the phase difference between the real-time phase of the A-phase signal and the B-phase signal corresponding to the zero mark matching signal and the reference phase.

2. The method according to claim 1, characterized in that During the effective period of the Z-phase signal, according to the effective edges of the A-phase signal and the B-phase signal, the real-time rotation direction of the encoder, and the reference rotation direction when determining the reference zero point, the zero mark matching signal is generated, including: In response to determining that the real-time rotation direction is the same as the reference rotation direction, a zero mark matching signal is generated at a target valid edge of the A-phase signal and the B-phase signal, wherein the target valid edge is a valid edge corresponding to when the reference zero point is determined.

3. The method according to claim 2, characterized in that During the effective period of the Z phase signal, according to the effective edges of the A phase signal and the B phase signal, the real-time rotation direction of the encoder, and the reference rotation direction when determining the reference zero point, generating the zero point mark matching signal also includes: In response to determining that the real-time rotation direction is opposite to the reference rotation direction, a zero mark matching signal is generated based on the matching relationship between the real-time phase corresponding to the effective edge and the reference phase, the real-time pulse width count value for the effective period of the Z-phase signal, and the pulse width of the Z-phase signal. The pulse width of the Z-phase signal is the number of overlaps between the effective period of the Z-phase signal and the effective edge.

4. The method according to claim 3, characterized in that In response to determining that the real-time rotation direction is opposite to the reference rotation direction, generating a zero mark matching signal according to a matching relationship between the real-time phase corresponding to the effective edge and the reference phase, a real-time pulse width count value during the effective period of the Z-phase signal, and a pulse width of the Z-phase signal includes: Based on the effective edge, real-time counting is performed for the effective period of the Z-phase signal to obtain the real-time pulse width count value; and During the period when the difference between the real-time pulse width count value and the pulse width of the Z-phase signal is less than or equal to a predetermined value, a zero mark matching signal is generated at the point where the real-time phase corresponding to the effective edge matches the reference phase.

5. The method according to claim 1, characterized in that According to the phase difference between the real-time phase of the A-phase signal and the B-phase signal corresponding to the zero mark matching signal and the reference phase, calibrating the position counter for the position of the encoder includes: In response to determining that the real-time rotation direction is the same as the reference rotation direction, determining a first reset value of a position counter with respect to the position of the encoder so as to reset the position counter at a zero mark matching signal, wherein when the phase difference is a negative number, the first reset value is a sum of a predetermined position count maximum value, 1, and the phase difference, and when the phase difference is a non-negative number, the first reset value is the phase difference; and In response to determining that the real-time rotation direction is opposite to the reference rotation direction, a second reset value of the position counter relative to the position of the encoder is determined so as to reset the position counter at the zero mark matching signal, wherein the second reset value is the difference between a predetermined position count maximum value and the phase difference.

6. The method according to claim 1, characterized in that Determining the reference zero point based on the A-phase signal, B-phase signal, and Z-phase signal from the encoder includes: Determine the reference zero point corresponding to the target effective edge of the A-phase signal and the B-phase signal during the effective period of the Z-phase signal, wherein the target effective edge is the first effective edge during the effective period of the Z-phase signal, and the effective edge is any one of the following: The transition edge of the A-phase signal; and The transition edge of the B-phase signal.

7. The method according to claim 1, characterized in that Also includes: Determining the phase information corresponding to each of the valid edges in sequence to determine the phase difference; as well as The real-time zero point of the encoder is determined based on the calibrated position counter.

8. An electronic device, characterized in that: include: at least one processor; as well as a memory communicatively coupled to the at least one processor; The memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the method according to any one of claims 1 to 7.

9. A computer-readable storage medium, characterized in that: A computer program is stored on a computer-readable storage medium, and when the computer program is executed by a machine, the method according to any one of claims 1 to 7 is implemented.

10. A computer program product tangibly stored on a non-transitory computer readable medium and comprising machine executable instructions which, when executed, cause a machine to perform the steps of the method according to any one of claims 1 to 7.

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