Control methods for time-of-flight sensors

Abstract

This application provides a control method for a Time-of-Flight (TOF) sensor. The method includes: alternately projecting light onto a first target and a second target using a light source comprising a first light source and a second light source; determining whether the first target and the second target are within an indistinguishable blind zone; and controlling the final output based on the determination result. By controlling the final output based on the determination of whether the target object and the background object are within the blind zone, this application prevents sensor output tremors (output malfunctions) and improves the sensor's detection performance.

Description

Technical Field

[0001] This application relates to the field of industrial automation technology, and in particular to a sensor. Background Technology

[0002] In industrial automation scenarios, time-of-flight (TOF) sensors are frequently used for distance detection of target objects. For ordinary TOF sensors, for example, when measuring distance, TOF sensors use a light source for illumination detection. After the light signal emitted by the TOF sensor's light source is reflected back to the sensor from the target object, the distance between the sensor and the target object can be calculated based on the time difference between the emission and reflection of the light signal.

[0003] Currently, in addition to using the ordinary TOF sensor mentioned above for target object distance detection, in order to expand the maximum measurement range of the TOF sensor, two different light sources can be used to alternately illuminate the target object for distance detection. Then, based on the measurement value returned by the sensor, it can be determined whether the current output is valid (ON) or invalid (OFF), thereby determining whether compensation processing is needed to obtain the actual distance of the target object.

[0004] It should be noted that the above description of the background technology is only for the purpose of providing a clear and complete explanation of the technical solutions of this application and facilitating understanding by those skilled in the art. It should not be assumed that these technical solutions are known to those skilled in the art simply because they have been described in the background technology section of this application. Summary of the Invention

[0005] The inventors discovered that in the TOF sensor that uses two different light sources to alternately project light onto the target object, the light spot emitted by the TOF sensor's light source will simultaneously hit the target object and the background object. When the target object and the background object are at certain specific distances, the output cannot distinguish between the target object and the background object. This may cause the output to alternate between valid (ON) and invalid (OFF), resulting in output ON / OFF jitter and an inability to stably detect the target object.

[0006] To address one of the aforementioned problems or other similar issues, this application provides a control method for a TOF sensor. By determining whether the target object and background object are in the recognition blind zone, the final output result is controlled, thereby preventing sensor output tremors (output malfunctions) and improving the sensor's product performance.

[0007] According to an embodiment of this application, a control method for a TOF sensor is provided, wherein the control method includes: alternately projecting light onto a first target (target object) and a second target (background object) using a projection light source including a first light source and a second light source; determining whether the first target (target object) and the second target (background object) are in a recognition blind zone that cannot be distinguished; and controlling the final output result based on the determination result.

[0008] One of the beneficial effects of this application embodiment is that, according to this application embodiment, the final output result is controlled by judging whether the target object and the background object are in the recognition blind zone, thereby preventing sensor output jitter (output malfunction) based on the judgment of whether they are in the recognition blind zone, and improving the detection performance of the sensor.

[0009] Specific embodiments of this application are disclosed in detail with reference to the following description and accompanying drawings, indicating how the principles of this application can be adopted. It should be understood that the embodiments of this application are not limited in scope. Within the spirit and scope of the appended claims, embodiments of this application include many changes, modifications, and equivalents. Attached Figure Description

[0010] The accompanying drawings, which form part of the specification, are used to provide a further understanding of the embodiments of this application and illustrate the implementation methods of this application, together with the textual description, to explain the principles of this application. Obviously, the drawings described below are merely some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings without creative effort. In the drawings:

[0011] Figure 1 This is a schematic diagram of a control method for a TOF sensor according to an embodiment of the first aspect of this application;

[0012] Figure 2 yes Figure 1 A schematic diagram illustrating the specific implementation method of step 102;

[0013] Figure 3 yes Figure 1 A schematic diagram illustrating the specific implementation method of step 103;

[0014] Figure 4 yes Figure 1 Another schematic diagram illustrating the specific implementation method of step 103;

[0015] Figure 5 This is a flowchart of a control method for a TOF sensor according to an embodiment of the first aspect of this application;

[0016] Figure 6This is a schematic diagram of the control device for a TOF sensor according to an embodiment of the second aspect of this application;

[0017] Figure 7 This is a schematic diagram of the judgment unit according to an embodiment of the second aspect of this application;

[0018] Figure 8 This is a schematic diagram of the output control unit according to an embodiment of the second aspect of this application. Detailed Implementation

[0019] Referring to the accompanying drawings, the foregoing and other features of this application will become apparent from the following description. Specific embodiments of this application are specifically disclosed in the description and drawings, illustrating partial implementations in which the principles of this application may be employed. It should be understood that this application is not limited to the described embodiments; rather, it includes all modifications, variations, and equivalents falling within the scope of the appended claims.

[0020] In the embodiments of this application, the terms "first," "second," etc., are used to distinguish different elements by name, but do not indicate the spatial arrangement or chronological order of these elements, and these elements should not be limited by these terms. The term "and / or" includes any one or more of the terms listed in association and all combinations thereof. The terms "comprising," "including," "having," etc., refer to the presence of the stated features, elements, components, or assemblies, but do not exclude the presence or addition of one or more other features, elements, components, or assemblies.

[0021] In the embodiments of this application, the singular forms "a," "the," etc., including the plural forms, should be broadly understood as "a kind" or "a class" rather than limited to the meaning of "an." Furthermore, the term "the" should be understood to include both the singular and plural forms, unless the context explicitly indicates otherwise. Additionally, the term "according to" should be understood as "at least partially based on…," and the term "based on" should be understood as "at least partially based on…," unless the context explicitly indicates otherwise.

[0022] The embodiments of this application will now be described with reference to the accompanying drawings. These embodiments are merely exemplary and are not intended to limit the scope of this application.

[0023] First aspect of the embodiments

[0024] In current TOF sensors that utilize dual light sources to alternately project light at two different periods (e.g., Range A and Range B), the maximum detection distances of the two light sources are different, with the maximum detection distance of Range A being S_RangeAMax and the maximum detection distance of Range B being S_RangeBMax.

[0025] The following example illustrates how this dual-light-source alternating projection TOF sensor triggers a compensation mechanism to extend the maximum range of the target object.

[0026] First, the first measurement value of the target object obtained from the first light signal emitted during Range A period and the second measurement value of the target object obtained from the second light signal emitted during Range B period are acquired. Then, the difference between the first and second measurement values ​​is used to determine whether compensation processing is needed. Specifically, the difference Δ between the first and second measurement values ​​is calculated. If the difference Δ is zero, no compensation processing is needed, and the actual distance value of the target object is the first measurement value (or the second measurement value). If the absolute value of the difference Δ is equal to the maximum detection distance S_RangeAMax of Range A, or if the difference Δ is equal to the difference between the maximum detection distance S_RangeBMax of Range B and the maximum detection distance S_RangeAMax of Range A, then compensation processing is triggered, thereby compensating for the difference. The actual distance to the target object is calculated using a compensation method. For example, when the absolute value of the difference Δ is equal to the maximum detection distance S_RangeAMax of RangeA, the actual distance to the target object is the first measured value of the target object plus the maximum detection distance S_RangeAMax of RangeA. When the absolute value of the difference Δ is equal to the difference between the maximum detection distance S_RangeBMax of RangeB and the maximum detection distance S_RangeAMax of RangeA, the actual distance to the target object is the first measured value of the target object plus the maximum detection distance S_RangeAMax of RangeA for the RangeA period, and the actual distance to the target object is the second measured value of the target object plus the maximum detection distance S_RangeBMax of RangeB for the RangeB period.

[0027] In current technology, for a TOF sensor with alternating dual-source illumination, each illumination cycle should normally detect two targets (the target object and the background object). Only under these conditions is the output of that illumination cycle valid. However, due to the existence of this compensation mechanism, the measured values ​​of the target object and the background object may be the same. In this case, the output will only show one detected target, and the sensor will automatically determine that the detected target is the background, outputting OFF (i.e., unable to distinguish between the target object and the background object, resulting in an invalid output). Specifically, the difference between the actual distance value of the target object and the actual distance value of the background object is equal to the maximum detection distance of RangeA, S_RangeAMax (or, the difference between the actual distance value of the target object and the actual distance value of the background object is equal to the maximum detection distance of RangeA, S_RangeAMax ± the fluctuation range of the sensor detection (this fluctuation range is determined by the sensor's optical circuit and optical...). When the characteristics determine that, for the RangeA period, the first measurement value of the target object and the first measurement value of the background object are the same, the number of targets detected is one background object (that is, the target object and the background object are within the indistinguishable recognition blind zone), and the output is OFF; when the difference between the actual distance value of the target object and the actual distance value of the background object is equal to the maximum detection distance of RangeB, which is S_RangeBMax (or, the difference between the actual distance value of the target object and the actual distance value of the background object is equal to the maximum detection distance of RangeB, which is S_RangeBMax ± the fluctuation range of the sensor detection (this fluctuation range is determined by the optical circuit and optical characteristics of the sensor)), for the RangeB period, the second measurement value of the target object and the second measurement value of the background object are the same, the number of targets detected is one background object (that is, the target object and the background object are within the indistinguishable recognition blind zone), and the output is OFF.

[0028] Table 1 shows the output results when the difference between the actual distance value of the target object and the actual distance value of the background object is equal to S_RangeAMax.

[0029] Table 1 shows the output results when the difference between the actual distance value of the target object and the actual distance value of the background object equals S_RangeAMax.

[0030] Measurement Detected target number Output RangeA 1 (Background) OFF RangeB 2 (Objective / Background) ON RangeA 1 (Background) OFF RangeB 2 (Objective / Background) ON

[0031] As can be seen from Table 1, when the light is projected in the Range A cycle, it is impossible to distinguish between the target object and the background object, so the output is OFF. However, when the light is projected in the Range B cycle, it is possible to distinguish between the target object and the background object, so the output is ON.

[0032] Table 2 shows the output results when the difference between the actual distance value of the target object and the actual distance value of the background object is equal to S_RangeBMax.

[0033] Table 2 shows the output results when the difference between the actual distance value of the target object and the actual distance value of the background object equals S_RangeBMax.

[0034] Measurement Detected target number Output RangeA 2 (Foreground / Background) ON RangeB 1 (Background) OFF RangeA 2 (Foreground / Background) ON RangeB 1 (Background) OFF

[0035] As can be seen from Table 2, when the light is projected in the Range B cycle, it is impossible to distinguish between the target object and the background object, thus outputting OFF. However, when the light is projected in the Range A cycle, it is possible to distinguish between the target object and the background object, thus outputting ON.

[0036] The output is ON during the Range A period and OFF during the Range B period, or OFF during the Range A period and ON during the Range B period, resulting in output jitter.

[0037] To address this problem, the first aspect of this application provides a control method for a TOF sensor.

[0038] Figure 1 This is a schematic diagram of a control method for a TOF sensor according to an embodiment of the first aspect of this application.

[0039] like Figure 1 As shown, the control method for a TOF sensor may include:

[0040] 101. Use a projection light source including a first light source and a second light source to alternately project light onto a first target (target object) and a second target (background object);

[0041] 102, determine whether the first target (target object) and the second target (background object) are within an indistinguishable recognition blind zone; and

[0042] 103, the final output result is controlled based on the judgment result.

[0043] Therefore, according to the above embodiments, the final output result is controlled by judging whether the first target (target object) and the second target (background object) are in the recognition blind zone. This can prevent sensor output jitter (output malfunction) based on the judgment of whether they are in the recognition blind zone, thereby improving the detection performance of the sensor.

[0044] In this embodiment, for example, the first light source can be the light source used during Range A period, the second light source can be the light source used during Range B period, the first target can be a target object, and the second target can be a background object. The distance value of the first target is measured using the first and second light sources. The first and second light sources alternately illuminate the target object and the background object; that is, the first light source illuminates both the target object and the background object simultaneously, and then the second light source illuminates both the target object and the background object simultaneously.

[0045] In the embodiments of this application, if the first target (target object) and the second target (background object) can be identified, that is, if two targets can be identified in the current illumination cycle, then the first target (target object) and the second target (background object) are not in the identification blind zone; if the first target (target object) and the second target (background object) cannot be identified, that is, if two targets cannot be identified in the current illumination cycle (only one target can be identified), then the first target (target object) and the second target (background object) are in the identification blind zone.

[0046] In this embodiment of the application, in step 103 above, the final output result is controlled based on the judgment result so that the output result is a valid result, thereby effectively preventing sensor output tremor (output malfunction).

[0047] Figure 2 yes Figure 1 A schematic diagram illustrating the specific implementation method of step 102.

[0048] In the embodiments of this application, such as Figure 2 As shown, specifically, determining whether the first target (target object) and the second target (background object) are within an indistinguishable recognition blind zone can include:

[0049] 201, determine whether the current light emission detection only detected one target;

[0050] 202. If it is determined that the current illumination detection only detects one target, determine whether the previous illumination detection detected two targets, including the first target (target object) and the second target (background object);

[0051] 203. Given that two targets were detected in the previous illumination detection, determine whether the difference between the measured value of the current target detected by the illumination detection and the preset distance is equal to the measured value of the first target (target object) detected by the previous illumination detection; and

[0052] 204. When it is determined that the difference is equal to the measurement value of the first target detected by the previous illumination, it is determined that the first target (target object) and the second target (background object) are within the recognition blind zone.

[0053] In this embodiment, the number of targets detected in the current illumination detection and the previous illumination detection, as well as the measurement value of a target detected in the current illumination detection and the measurement value of the first target (target object) detected in the previous illumination detection, are used to comprehensively determine whether the target object and the background object are in the recognition blind zone. This can accurately determine whether the target object and the background object in the current detection cannot be distinguished.

[0054] In this embodiment, the preset distance can be preset in advance. For example, it can be set according to the optical characteristics of the TOF sensor itself. Specifically, when the current light emission detection is performed using a first light source, the preset distance can be the maximum detection distance of the first light source. Alternatively, when the current light emission detection is performed using a second light source, the preset distance can be the maximum detection distance of the second light source.

[0055] In this embodiment, for example, when the light source (first light source) used in the current illumination detection is a Range A cycle, the preset distance is the maximum detection distance of Range A, which is S_RangeAMax. That is, when the current illumination detection is a Range A cycle, in step 203 above, it is determined whether the difference between the measured value of a target detected in the current illumination and the maximum detection distance of Range A, S_RangeAMax, is equal to the measured value of the first target (target object) detected in the previous illumination. When the light source (second light source) used in the current illumination detection is a Range B cycle, the preset distance is the maximum detection distance of Range B, which is S_RangeBMax. That is, when the current illumination detection is a Range B cycle, in step 203 above, it is determined whether the difference between the measured value of a target detected in the current illumination and the maximum detection distance of Range B, S_RangeBMax, is equal to the measured value of the first target (target object) detected in the previous illumination.

[0056] Figure 3 yes Figure 1 A schematic diagram of the specific implementation method of step 103.

[0057] like Figure 3 As shown, the final output result (103) controlled based on the judgment result can include:

[0058] 301. When the judgment result indicates that the first target (target object) and the second target (background object) are within the recognition blind zone, delete the first result (invalid result) output by detecting using the corresponding light source when the first target (target object) and the second target (background object) are within the recognition blind zone; and

[0059] 302, the final output is controlled by the second result (valid result) after deleting the first result (invalid result).

[0060] Therefore, by deleting invalid data (invalid result OFF, i.e., only one target is detected but no target object is detected), it is ensured that each output is a normal action (i.e., valid result ON).

[0061] Table 3 shows the output results before and after deleting invalid data when the output result of the RangeB periodic projection is invalid.

[0062] Table 3. Output results before and after deleting invalid data.

[0063]

[0064] As shown in Table 3, all invalid (OFF) data from the RangeB cycle outputs were removed, ensuring that all output results were valid (ON), thus preventing output jitter (ON / OFF). After removing the invalid data, the distance value of the detected target object was finally obtained based on the valid output results (measurements when the output results were valid).

[0065] In the embodiments of this application, the purpose of controlling the final output result based on the determination result of whether the target object and the background object are in the recognition blind zone is to make the output result valid. The above is only an example of one specific implementation method to make the output result valid. However, this application is not limited to the above implementation method of deleting invalid data. All implementation methods that control the final output result based on the determination result to make the output result valid (output valid result) are included in this application.

[0066] In this embodiment of the application, controlling the final output result (302 above) based on the second result (valid result) after deleting the first result (invalid result) may include:

[0067] The final output result is controlled based on the second result (valid result) of the previous illumination detection or based on the second results (valid results) of multiple illumination detections prior to the current illumination detection. For example, multiple consecutive valid outputs can be used to control the final output result to be valid, or the validity of the previous output result can be used to control the final output result to be valid.

[0068] In the embodiments of this application, Figure 3 This demonstrates how to control the final output based on the judgment result when the first target (target object) and the second target (background object) are within the recognition blind zone.

[0069] Figure 4 yes Figure 1 Another schematic diagram of the specific implementation method of step 103.

[0070] like Figure 4 As shown, the final output result (103) controlled based on the judgment result can include:

[0071] 401. When the judgment result is that the first target (target object) and the second target (background object) are not within the recognition blind zone, the final output result is controlled to be valid.

[0072] In this embodiment of the application, section 401 provides how to control the final output result based on the judgment result when the first target (target object) and the second target (background object) are not within the recognition blind zone. That is, the output result is directly valid at this time. In other words, the measured value of the target object measured during the Range A cycle and the measured value of the target object measured during the Range B cycle are both valid values ​​and can be used as valid data for finally obtaining the distance value of the target object.

[0073] In this embodiment of the application, in step 201 above, when it is determined that the current illumination detection includes two targets, namely a first target (target object) and a second target (background object), step 103 above, which controls the final output result based on the judgment result, may include controlling the final output result to be valid. That is, if the current detection does not detect only one target, and it is determined that the target object and the background object are not within the recognition blind zone, then the output result is directly valid.

[0074] In the embodiments of this application, in steps 201 and 202 above, if it is determined that the current illumination detection detects a target and the previous illumination detection also detected a target, the final output result is controlled to be valid. That is, although the current detection only detects one target, the previous detection also only detected one target, so it cannot be determined that the target object and the background object are within the recognition blind zone, and therefore the output result is valid.

[0075] In this embodiment, in steps 201, 202, and 204 above, if the current illumination detection detects one target, the previous illumination detection detected two targets including a first target and a second target, and the difference between the measured value of the target detected in the current illumination detection and the preset distance is not equal to the measured value of the first target detected in the previous illumination detection, the final output result is controlled to be valid. That is, although the current detection only detects one target, and the previous detection detected both the target object and the background object, the difference between the measured value of the target detected in the current illumination detection and the preset distance is not equal to the measured value of the first target detected in the previous illumination detection. Therefore, it cannot be determined that the target object and the background object are within the recognition blind zone, and the output result is valid.

[0076] In the embodiments of this application, the above examples illustrate how to determine whether the first target (target object) and the second target (background object) are in a recognition blind zone that cannot be distinguished. However, this application is not limited to this. Any implementation method for determining whether the first target (target object) and the second target (background object) are in a recognition blind zone that cannot be distinguished is included in this application.

[0077] The following example illustrates the control method of the aforementioned TOF sensor by describing the specific process of whether the target object and the background object are in a blind zone where they cannot be distinguished.

[0078] Figure 5 This is a flowchart of a control method for a TOF sensor according to an embodiment of the first aspect of this application.

[0079] like Figure 5 As shown, the control method for a TOF sensor may include:

[0080] 501, using a projection light source including a first light source and a second light source to alternately project light onto a first target (target object) and a second target (background object);

[0081] For example, a first light source and a second light source are used to alternately illuminate a first target (target object) and a second target (background object) during Range A and Range B periods, respectively.

[0082] 502, Determine whether the current illumination detection detects only one target; if it is determined that the current illumination detection detects only one target, proceed to 503; if it is determined that the current illumination detection detects two targets, including the first target (target object) and the second target (background object), proceed to 506.

[0083] For example, if the current illumination detection is in the Range B period, then it is determined whether there is only one target detected in the Range B period. If only one target is detected, then the measurement value MC of that single target in the Range B period is obtained. 2-B For example, if the current illumination detection is in the Range A period, then it is determined whether there is only one target detected in the Range A period. If only one target is detected, then the measurement value MC of that single target in the Range A period is obtained. 2-A .

[0084] 503, determine whether the previous illumination detection detected two targets, including the first target (target object) and the second target (background object); if it is determined that the previous illumination detection detected two targets, including the first target (target object) and the second target (background object), proceed to 504; if it is determined that the previous illumination detection only detected one target, proceed to 506.

[0085] For example, if the current illumination detection is in Range B period and the previous illumination detection was in Range A period, then it is determined whether there are two targets in the detection results of Range A period; if two targets are detected in Range A period, then the measurement value MP of the first target is recorded in Range A period. 1-A The measured value of the second target MP 2-A For example, if the current illumination detection is in Range A period, and the previous illumination detection was in Range B period, then it is determined whether there are two targets in the detection results of Range B period; if two targets are detected in Range B period, then the measurement value MP of the first target is recorded in Range B period. 1-B The measured value of the second target MP 2-B .

[0086] 504. Determine whether the difference between the measured value of a target detected in the current illumination and the preset distance is equal to the measured value of the first target (target object) detected in the previous illumination. If they are equal, proceed to 505; otherwise, proceed to 506.

[0087] For example, if the current light projection detection is in the RangeB period, then the preset distance is the maximum detection distance S_RangeBMax in the RangeB period. Therefore, the determination is based on the measurement value MC of the target within the RangeB period. 2-B Is the difference between the maximum detection distance S_RangeBMax in the RangeB cycle equal to the measurement value M of the first target detected in the RangeA cycle? 1-A (MC 2-B -S_RangeBMax=MP1-A ? ).

[0088] For example, if the current light projection detection is in the RangeA period, then the preset distance is the maximum detection distance S_RangeAMax in the RangeA period. Therefore, the determination is based on the measurement value MC of the target within the RangeA period. 2-A Is the difference between the maximum detection distance S_RangeAMax in the RangeA cycle equal to the measurement value MP of the first target detected in the RangeB cycle? 1-B (MC 2-A -S_RangeAMax=MP 1-B ? ).

[0089] 505, if the first target (target object) and the second target (background object) are determined to be within the recognition blind zone, delete the data output of the current light projection detection.

[0090] For example, if the current light detection is in the Range B period, then delete the OFF result output in the Range B period; if the current light detection is in the Range A period, then delete the OFF result output in the Range A period.

[0091] 506, the final output result is controlled based on the judgment result.

[0092] For example, if in step 502 it is determined that the current illumination detection detects two targets, including a first target (target object) and a second target (background object), then the final output result of the control is directly valid; for example, if in step 503 it is determined that the current illumination detection detects one target and the previous illumination detection also detected one target, then the final output result of the control is valid; for example, if in step 504 it is determined that the difference between the measured value of a target detected in the current illumination and the preset distance is not equal to the measured value of the first target (target object) detected in the previous illumination, then the final output result of the control is valid.

[0093] In this embodiment of the application, in step 506, the final output result can be determined based on the valid output result of a single detection, or the final output result can be determined based on the valid output results of multiple detections.

[0094] According to the above embodiments, the final output result is controlled by judging whether the first target (target object) and the second target (background object) are in the recognition blind zone. In this way, sensor output tremors (output malfunctions) can be prevented based on the judgment of whether they are in the recognition blind zone, thereby improving the detection performance of the sensor.

[0095] Second aspect of the embodiments

[0096] The second aspect of this application provides a control device for a Time-of-Flight (TOF) sensor. Since the principle behind the problem solved by the TOF sensor control device is similar to that of the TOF sensor control method, the implementation of the TOF sensor control device can be found in the implementation of the TOF sensor control method; repeated details will not be described again.

[0097] Figure 6 This is a schematic diagram of the control device for a TOF sensor according to an embodiment of the second aspect of this application.

[0098] like Figure 6 As shown, the control device 600 of the TOF sensor may include a light projection unit 601, a judgment unit 602, and an output control unit 603. The light projection unit 601 is used to alternately project light onto a first target (target object) and a second target (background object) using a light projection light source including a first light source and a second light source. The judgment unit 602 is used to determine whether the first target (target object) and the second target (background object) are in a recognition blind zone that cannot be distinguished. The output control unit 603 is used to control the final output result based on the judgment result.

[0099] According to the above embodiments, the output control unit 603 controls the final output result by judging the result of the judging unit 602, thereby preventing sensor output jitter (output malfunction) based on the judgment of whether it is in the recognition blind zone, and improving the detection performance of the sensor.

[0100] Figure 7 This is a schematic diagram of the judgment unit according to an embodiment of the second aspect of this application.

[0101] like Figure 7 As shown, the judgment unit 602 may include: a first judgment module 6021, a second judgment module 6022, a third judgment module 6023, and a determination module 6024; wherein, the first judgment module 6021 is used to determine whether the current illumination detection detects only one target; the second judgment module 6022 is used to determine whether the previous illumination detection detected two targets, including a first target (target object) and a second target (background object), when the first judgment module 6021 determines that the current illumination detection detects only one target; the third judgment module 6023 is used to determine whether the difference between the measured value of the target detected in the current illumination detection and the preset distance is equal to the measured value of the first target (target object) detected in the previous illumination detection, when the second judgment module 6022 determines that the difference is equal to the measured value of the first target detected in the previous illumination detection; the determination module 6024 is used to determine that the first target (target object) and the second target (background object) are within the recognition blind zone when the third judgment module 6023 determines that the difference is equal to the measured value of the first target detected in the previous illumination detection.

[0102] Figure 8 This is a schematic diagram of the output control unit according to an embodiment of the second aspect of this application.

[0103] like Figure 8 As shown, the output control unit 603 may include a data deletion module 6031 and an output control module 6031. The data deletion module 6031 is used to delete the first result (invalid result) output by the light source corresponding to the first target (target object) and the second target (background object) when the judgment result of the judgment unit 602 is that the first target (target object) and the second target (background object) are in the recognition blind zone. The output control module 6031 is used to control the final output result according to the second result (valid result) after deleting the first result (invalid result).

[0104] According to the above embodiments, the output control unit 603 controls the final output result by judging the result of the judging unit 602, thereby preventing sensor output jitter (output malfunction) based on the judgment of whether it is in the recognition blind zone, and improving the detection performance of the sensor.

[0105] The present application has been described above with reference to specific embodiments. However, those skilled in the art should understand that these descriptions are exemplary and not intended to limit the scope of protection of the present application. Those skilled in the art can make various modifications and variations to the present application based on its spirit and principles, and these modifications and variations are also within the scope of the present application.

[0106] Preferred embodiments of this application have been described above with reference to the accompanying drawings. Many features and advantages of these embodiments are apparent from this detailed description, and therefore the appended claims are intended to cover all such features and advantages of these embodiments that fall within their true spirit and scope. Furthermore, since many modifications and alterations will readily occur to those skilled in the art, the embodiments of this application are not intended to be limited to the precise structures and operations illustrated and described, but rather to encompass all suitable modifications and equivalents falling within their scope.

Claims

1. A control method for a time-of-flight (TOF) sensor, characterized in that, The control method includes: The first target and the second target are alternately illuminated by a light source including a first light source and a second light source; Determine whether the first target and the second target are in a blind spot where they cannot be distinguished; The final output result is controlled based on the judgment result.

2. The control method according to claim 1, wherein, The determination of whether the first target and the second target are indistinguishable recognition blind spots includes: Determine whether the current light emission detection detects only one target; If it is determined that the current illumination detection only detects one target, it is then determined whether the previous illumination detection detected two targets, including the first target and the second target. If it is determined that the two targets were detected in the previous illumination detection, it is determined whether the difference between the measured value of the target detected in the current illumination and the preset distance is equal to the measured value of the first target detected in the previous illumination. When the difference is determined to be equal to the measurement value of the first target detected in the previous illumination, it is determined that the first target and the second target are within the recognition blind zone.

3. The control method according to claim 2, wherein, When the first light source is used for the current light projection detection, the preset distance is the maximum detection distance of the first light source.

4. The control method according to claim 2, wherein, When the current light emission detection uses the second light source, the preset distance is the maximum detection distance of the second light source.

5. The control method according to claim 1, wherein, The final output result controlled based on the judgment result includes: When the determination result indicates that the first target and the second target are within the recognition blind zone, the first result output by detecting using the light source corresponding to when the first target and the second target are within the recognition blind zone is deleted; and The final output is controlled by the second result after deleting the first result.

6. The control method according to claim 5, wherein, The step of controlling the final output result based on the second result after deleting the first result includes: The final output result is controlled based on the second result of the previous illumination detection or based on the second result of multiple illumination detections prior to the current illumination detection.

7. The control method according to claim 1, wherein, The process of controlling the final output result based on the judgment result includes: When the judgment result indicates that the first target and the second target are not within the recognition blind zone, the final output result is controlled to be valid.

8. The control method according to claim 2, wherein, The process of controlling the final output result based on the judgment result includes: If the current illumination detection detects two targets, including the first target and the second target, the final output result is controlled to be valid.

9. The control method according to claim 2, wherein, The process of controlling the final output result based on the judgment result includes: If the current illumination detection detects a target and the previous illumination detection also detected a target, the final output result is controlled to be valid.

10. The control method according to claim 2, wherein, The process of controlling the final output result based on the judgment result includes: If the current illumination detection detects one target, the previous illumination detection detects two targets including the first target and the second target, and the difference is not equal to the measured value of the first target detected in the previous illumination detection, the final output result is controlled to be valid.

Images