Detection circuit, detection method of digital level signal and related device

Abstract

The application relates to an output state detection circuit, a detection method and related devices of a digital level signal, which are connected with a microprocessor and a safety main controller, wherein the output state detection circuit comprises a signal output module, a signal energy discharge module and a signal voltage feedback module. By detecting whether the digital level signal can be closed in real time, a fault can be detected in advance and triggered, the safety risk is reduced, an energy discharge loop is added, the bus energy is discharged within a specified time, if the voltage of the digital level signal is detected to exceed a specified time and not to drop to a set value, a fault state is triggered, the whole personnel detection protection loop responds in time, and the fault can be detected in advance.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of circuit detection, and in particular to a detection circuit and method for a digital level signal and related devices. BACKGROUND

[0002] With the development of technology, robots have been applied in multiple fields. Robots belong to mobile equipment and are divided into mobile robots and fixed robots, and are equipment that can endanger personnel safety. Among them, personnel detection equipment for personnel detection usually outputs personnel detection results to a safety master controller in the form of a digital level signal (DO). In the scene of human-computer interaction, the human-computer interaction scene belongs to a situation with high safety requirements. Therefore, how to detect whether the digital level signal can be closed in real time, detect in advance and trigger a fault, or otherwise a danger may be caused due to slow response time of the equipment. SUMMARY

[0003] To overcome the problems in the related art, the present application provides a detection circuit and method for a digital level signal and related devices.

[0004] The first aspect of the present application provides an output state detection circuit for a digital level signal, which is connected to a microprocessor and a safety master controller, wherein the output state detection circuit comprises a signal output module, a signal energy discharge module and a signal voltage feedback module, wherein:

[0005] The signal output module is configured to receive a first control signal sent by the microprocessor and output a digital level signal to the safety master controller. The first control signal is a control signal for controlling the closing of the output level signal or a control signal for controlling the opening of the output level signal.

[0006] The signal energy discharge module is configured to obtain the digital level signal and discharge energy of the digital level signal when receiving a second control signal sent by the microprocessor.

[0007] The signal voltage feedback module is configured to collect voltage of the digital level signal in real time and feed back the voltage of the digital level signal to the microprocessor.

[0008] In some embodiments, a first end of the signal output module is connected to a first pin of the microprocessor, a second end of the signal output module is connected to a digital level signal input module of the safety main controller, a first end of the signal energy discharge module is connected to a second pin of the microprocessor, a second end of the signal energy discharge module is connected to the second end of the signal output module, a third end of the signal energy discharge module is connected to a first end of the signal voltage feedback module, and a second end of the signal voltage feedback module is connected to a third pin of the microprocessor.

[0009] In some embodiments, the signal output module comprises a first control circuit, a second control circuit, a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a first drive circuit, a first protection circuit, a second protection circuit, and a third protection circuit, wherein:

[0010] A first end of the first control circuit is connected to a first end of the second control circuit and connected through one end of the fourth resistor, another end of the fourth resistor is connected to VCC_DO, a second end of the second control circuit is connected to the first pin of the microprocessor as a first end of the signal output module, a second end of the first control circuit is connected to a third end of the second control circuit and grounded; a third end of the first control circuit is connected to a third end of the first drive circuit;

[0011] A fourth end of the first drive circuit is connected to VCC_DO, a third end is connected to VCC_DO through the second resistor; an eighth end of the first drive circuit is grounded through the third resistor; a fifth end of the first drive circuit is connected to the digital level signal input module of the safety main controller as a second end of the signal output module; a sixth end of the first drive circuit is connected to the second pin of the microprocessor as a feedback end of the signal output module, the sixth end of the first drive circuit is connected to the power supply VCC_3V3 through the first resistor, a seventh end of the first drive circuit is grounded through the fifth resistor; a ninth end of the first drive circuit is grounded;

[0012] A first end of the first protection circuit, a first end of the second protection circuit, and a first end of the third protection circuit are connected, and a common end thereof is connected to the fifth end of the first drive circuit; a second end of the first protection circuit, a second end of the second protection circuit, and a second end of the third protection circuit are connected, and a common end thereof is grounded.

[0013] In some embodiments, the first protection circuit is a capacitor.

[0014] In some embodiments, the second protection circuit is a freewheeling diode.

[0015] In some embodiments, the third protection circuit is a transient diode.

[0016] In some embodiments, the signal energy bleed module comprises a third control circuit, a first bleed circuit, a second bleed circuit, a third bleed circuit, a seventh resistor, a ninth resistor, a tenth resistor, an eleventh resistor, and a fourteenth resistor, wherein:

[0017] A first end of the first bleed circuit is connected to a second end of the signal energy bleed module and a second end of the signal output module, a second end of the first bleed circuit is connected to a fifth pin, a sixth pin, a seventh pin, and an eighth pin of the second bleed circuit, and a third end of the signal energy bleed module is connected to a first end of the signal voltage feedback module, a first pin, a second pin, and a third pin of the second bleed circuit are connected, and a common end thereof is connected to one end of the third bleed circuit, and the other end of the third bleed circuit is grounded;

[0018] One end of the fourteenth resistor is connected to a second pin of the microprocessor as a first end of the signal energy bleed module, and the other end thereof is connected to a gate of the third control circuit, and a common end thereof is connected to a power supply VCC_3V3 through the ninth resistor;

[0019] A first end of the third control circuit is connected to a power supply VCC_DO through the seventh resistor, and a common end thereof is connected to one end of the tenth resistor, a second end of the third control circuit is grounded, and the other end of the tenth resistor is connected to a fourth pin of the second bleed circuit, and a common end thereof is grounded through the eleventh resistor.

[0020] In some embodiments, the first bleed circuit is a bleed diode.

[0021] In some embodiments, the second bleed circuit is an NMOS switch tube.

[0022] In some embodiments, the third bleed circuit is a bleed resistor.

[0023] In some embodiments, the signal voltage feedback module comprises a sixth resistor, an eighth resistor, and a thirteenth resistor, wherein:

[0024] One end of the sixth resistor is connected to a third end of the signal energy bleed module as a first end of the signal voltage feedback module, the other end of the sixth resistor is connected to one end of the eighth resistor and the thirteenth resistor respectively, the other end of the thirteenth resistor is grounded, and the other end of the eighth resistor is connected to a third pin of the microprocessor as a second end of the signal voltage feedback module.

[0025] The second aspect of the application provides a method for detecting the output state of a digital level signal, based on an output state detection system, which comprises: the output state detection circuit for the digital level signal, a microprocessor and a safety main controller, wherein the output state detection circuit is connected to the microprocessor and the safety main controller respectively, and the method comprises:

[0026] When it is detected that there is an obstacle close to the digital level signal, the first control signal output by the microprocessor to the output state detection circuit is low, and the off state of the digital level signal takes effect;

[0027] The second control signal output by the microprocessor to the output state detection circuit is low, and the energy discharge is started;

[0028] The microprocessor acquires the voltage of the digital level signal in real time, and judges the output state of the digital level signal according to a preset condition.

[0029] The microprocessor acquires the voltage of the digital level signal in real time, and judges the output state of the digital level signal according to a preset condition, which comprises:

[0030] The microprocessor acquires the voltage of the digital level signal in real time, and compares the voltage of the digital level signal with a set power voltage;

[0031] When the off state of the digital level signal takes effect and the voltage of the digital level signal is greater than the set voltage, a first control instruction is sent to the safety main controller, and the first control instruction is used to control the safety main controller to execute a safety strategy;

[0032] When the off state of the digital level signal is invalid and the absolute value of the difference between the voltage of the digital level signal and the set voltage is greater than the set voltage, a first control instruction is sent to the safety main controller, and the first control instruction is used to control the safety main controller to execute a safety strategy;

[0033] When the off state of the digital level signal is invalid, a second control instruction is sent to the output state detection circuit, and the second control instruction is used to control the output state detection circuit to execute a periodic self-check of the digital level signal.

[0034] In some embodiments, the method further comprises:

[0035] When it is detected that there is no obstacle close to the digital level signal, the first control signal output by the microprocessor to the output state detection circuit is high, and the off state of the digital level signal is invalid;

[0036] The microprocessor acquires the voltage of the digital level signal in real time, and judges the output state of the digital level signal according to a second preset condition.

[0037] In some embodiments, the microprocessor acquires the voltage of the digital level signal in real time, and judges the output state of the digital level signal according to a second preset condition, including:

[0038] The microprocessor acquires the voltage of the digital level signal in real time, and judges whether the voltage of the digital level signal is within a set power supply voltage range.

[0039] When the voltage of the digital level signal is not within the set power supply voltage range, a first control instruction is sent to the safety main controller, and the first control instruction is used to control the safety main controller to execute a safety strategy.

[0040] When the voltage of the digital level signal is within the set power supply voltage range, a second control instruction is sent to the output state detection circuit, and the second control instruction is used to control the output state detection circuit to execute a digital level signal periodic self-check.

[0041] The third aspect of the present application provides an output state detection system, which comprises the output state detection circuit of the digital level signal, the microprocessor and the safety main controller as described above, and the output state detection circuit is connected with the microprocessor and the safety main controller respectively.

[0042] The fourth aspect of the present application provides a robot, which comprises a robot body and the output state detection system as described above arranged on the robot body.

[0043] The technical scheme provided by the present application can include the following beneficial effects:

[0044] This application provides a digital level signal output status detection circuit, detection method, and related apparatus. The output status detection circuit is connected to a microprocessor and a safety main controller. The circuit includes a signal output module, a signal energy discharge module, and a signal voltage feedback module. The signal output module receives a first control signal from the microprocessor and outputs a digital level signal to the safety main controller. This first control signal is a control signal to turn off the output level signal. The signal energy discharge module acquires the digital level signal and discharges energy from it upon receiving a second control signal from the microprocessor. The signal voltage feedback module collects the voltage of the digital level signal in real time and feeds it back to the microprocessor. This application, by detecting in real time whether the digital level signal can be turned off, can detect and trigger faults in advance, reducing safety risks. It also adds an energy discharge loop, allowing bus energy to be released within a specified time. If the voltage of the digital level signal does not drop to a set value after a specified time, a fault state is triggered, ensuring timely response of the entire personnel detection and protection circuit and early fault detection.

[0045] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description

[0046] The above and other objects, features and advantages of this application will become more apparent from the more detailed description of exemplary embodiments thereof in conjunction with the accompanying drawings, wherein the same reference numerals generally represent the same components in the exemplary embodiments thereof.

[0047] Figure 1 This is a schematic diagram of the output state detection circuit of the digital level signal shown in an embodiment of this application;

[0048] Figure 2 This is a schematic diagram of the signal output module shown in an embodiment of this application;

[0049] Figure 3 This is a schematic diagram of the signal energy discharge module shown in the embodiments of this application;

[0050] Figure 4 This is a schematic diagram of the signal voltage feedback module shown in an embodiment of this application;

[0051] Figure 5 This is a schematic diagram of the specific structure of the output state detection circuit of the digital level signal shown in the embodiment of this application;

[0052] Figure 6 This is a schematic diagram of the self-test process during state switching, as shown in the embodiments of this application;

[0053] Figure 7 is a periodic self-checking process diagram shown by the embodiment of the present application. DETAILED DESCRIPTION

[0054] The preferred embodiments of the present application will be described in more detail by referring to the attached drawings. Although the preferred embodiments of the present application are shown in the drawings, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided so that the present application can be more thoroughly and completely conveyed to those skilled in the art.

[0055] The terms used in the present application are merely for the purpose of describing particular embodiments and are not intended to limit the present application. The singular forms "a," "an," and "the" used in the present application and the appended claims are also intended to include the plural forms, unless the context clearly indicates otherwise. It should also be understood that the term "and / or" used in the present application means and includes any or all possible combinations of one or more associated listed items.

[0056] It should be understood that although the terms "first", "second", "third", etc. can be used in the present application to describe various information, these information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, the first information can also be referred to as the second information, and similarly, the second information can also be referred to as the first information without departing from the scope of the present application. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "a plurality of" is two or more, unless otherwise specifically limited.

[0057] The existing digital level signal control mode is divided into open loop control and monitoring whether the digital level signal output is normal, such as: using open loop control mode, that is, signal triggering controls signal output, and does not detect whether the output is normal, such as touch edge, which is disconnected in normal operation, and is closed when touching the obstacle. Using output closed loop detection mode, that is, signal triggering controls signal output, and whether the signal is normal is collected by AD sampling mode.

[0058] The applicant found in the research that, as a digital level signal in response to personnel detection, the open-loop control mode cannot meet the safety requirements because this digital level control mode only controls the turn-off of the digital level signal and does not detect whether the digital level signal is actually turned off. When the personnel detection device detects that a person is approaching, it needs to control the mobile equipment to stop operating in time. For example, when a person is actually approaching, the personnel detection device controls the digital level signal to turn off. If the digital level signal is not normally turned off at this time, the abnormality cannot be detected, and further safety measures cannot be taken, which will inevitably bring danger to the person.

[0059] As a digital level signal in response to personnel detection, the output closed-loop detection mode is used. This mode adds the output signal detection function on the basis of the open-loop mode, but does not perform real-time detection on the turn-off ability of the digital level signal. When the personnel detection device detects that a person is approaching, the digital level signal must drop to the voltage recognized by the safety main controller within a specified time, so as to notify the safety main controller to execute the safety strategy as soon as possible. If the equipment does not support real-time detection of whether the digital level signal can be normally turned off, when the personnel detection device detects that a person is approaching, the digital level signal is controlled to turn off, and the personnel detection device detects that the digital level signal is not turned off, and then controls the digital level signal for indicating a fault to turn off. The entire safety reaction link is relatively long, and there is still a safety risk.

[0060] The falling edge of the digital level signal when turning off cannot be controlled and detected in the above two modes. For example, the personnel detection equipment triggers the digital level signal of personnel detection. When no person is detected to approach, a 24V digital level signal is output to the safety main controller of the mobile equipment. When a person is detected to approach, the safety main controller considers that the digital level signal is valid only when the 24V digital level signal voltage drops to 10V. The time for the 24V to drop to 10V is related to the residual energy of the signal line and the energy discharge load. The human-machine interaction scene belongs to a scene with high safety requirements. The falling time of the digital level signal is very important. Otherwise, danger may be caused due to slow response time of the equipment.

[0061] In view of the above shortcomings, the application provides an output state detection circuit and a detection method of a digital level signal. By detecting whether the digital level signal can be turned off in real time, a fault can be detected in advance and triggered, the safety risk is reduced, and an energy discharge loop is added to release the bus energy within a specified time. If it is detected that the voltage of the digital level signal does not drop to the set value within the specified time, a fault state is triggered, so that the entire personnel detection protection loop responds in time, and the fault can be detected in advance.

[0062] The technical solutions of the embodiments of the application are described in detail below with reference to the drawings.

[0063] Figure 1is a schematic diagram of an output state detection circuit structure of a digital level signal according to an embodiment of the present application. Referring to Figure 1 The embodiment of the present application provides an output state detection circuit of a digital level signal, and the output state detection detection circuit 1 is connected with a microprocessor 2 and a safety main controller 3, wherein the output state detection circuit comprises a signal output module 11, a signal energy discharge module 12 and a signal voltage feedback module 13, and wherein:

[0064] The signal output module 11 is used for receiving a first control signal sent by the microprocessor 2 and outputting a digital level signal to the safety main controller 3, and the first control signal is a control signal for controlling to close the output level signal or a control signal for controlling to open the output level signal; the signal energy discharge module 12 is used for acquiring the digital level signal and discharging energy of the digital level signal when receiving a second control signal sent by the microprocessor 2; and the signal voltage feedback module 13 is used for collecting voltage of the digital level signal in real time and feeding back the voltage of the digital level signal to the microprocessor 2.

[0065] In specific embodiments, as shown in Figure 2 The first end of the signal output module 11 is connected with a first pin of the microprocessor 2, the second end of the signal output module 11 is connected with a digital level signal input module of the safety main controller 3, the first end of the signal energy discharge module 12 is connected with a second pin of the microprocessor 2, the second end of the signal energy discharge module 12 is connected with the second end of the signal output module 11, the third end of the signal energy discharge module 12 is connected with the first end of the signal voltage feedback module 13, and the second end of the signal voltage feedback module 13 is connected with a third pin of the microprocessor 2.

[0066] In specific embodiments, as shown in Figure 2 The signal output module 11 comprises a first control circuit Q1, a second control circuit Q2, a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a first driving circuit U1, a first protection circuit C1, a second protection circuit D2 and a third protection circuit TVS1, and wherein:

[0067] The gate of the first control circuit Q1 is connected with the source of the second control circuit Q2, and is connected with one end of the fourth resistor R4, the other end of the fourth resistor R4 is connected with VCC_DO, the gate of the second control circuit Q2 is connected with the first pin of the microprocessor 2 as the first end of the signal output module 11, the drain of the first control circuit Q1 is connected with the drain of the second control circuit Q2 and is grounded; the source of the first control circuit Q1 is connected with the third pin of the first drive circuit U1;

[0068] The fourth pin of the first drive circuit U1 is connected with VCC_DO, the third pin is connected with VCC_DO through the second resistor R2; the eighth pin of the first drive circuit U1 is grounded through the third resistor R3; the fifth pin of the first drive circuit U1 is connected with the digital level signal input module of the safety main controller 3 as the second end of the signal output module 11; the sixth pin of the first drive circuit U1 is connected with the second pin of the microprocessor 2 as the feedback end of the signal output module 11, the sixth pin of the first drive circuit U1 is connected with the power supply VCC_3V3 through the first resistor R1, the seventh pin of the first drive circuit U1 is grounded through the fifth resistor R5; the ninth pin of the first drive circuit U1 is grounded.

[0069] The first end of the first protection circuit C1, the first end of the second protection circuit D2 and the first end of the third protection circuit TVS1 are connected, and the common end is connected with the fifth pin of the first drive circuit U1; the second end of the first protection circuit C1, the second end of the second protection circuit D2 and the second end of the third protection circuit TVS1 are connected, and the common end is grounded.

[0070] It should be noted that the first control circuit Q1 and the second control circuit Q2 can be MOS tubes or triodes, and the specific connection ends can be connected according to actual needs, and the specific connection is not limited here.

[0071] In specific embodiments, as shown in Figure 2 The first protection circuit is a capacitor C1, the second protection circuit is a freewheeling diode D2, and the third protection circuit is a transient diode TVS1.

[0072] It should be noted that, as Figure 2As shown, the signal output module mainly consists of control circuit Q1, Q2, drive circuit U1, protection circuit C1, D2 and TVS1. Q1 and Q2 are NPN triodes, the control signal of the base stage of Q2 comes from the microcontroller, and Q1 is controlled by the collector of Q2. When the device is powered on, the microcontroller has not started yet, Q2 is not conductive, Q1 is conductive due to the pull-up of resistor R4 to VCC_DO, so that the 3-pin of U1 is connected to GND, thereby turning off the output, which is to ensure that DO is in the off state during the boot process. When the microcontroller starts normally, the microcontroller can control the opening and closing state of U1 because DO_Ctrl is connected to the GPIO pin of the microcontroller. U1 is a power switch chip in this circuit, which has over-temperature protection and over-current protection functions. The sixth pin is the feedback signal when the chip detects over-temperature or over-current fault. This pin is an open-drain output, and the internal MOS tube is conductive to ground to output 0V when there is a fault, and the internal MOS is closed when there is no fault. The DO_FAULT signal is pulled up to the power supply VCC_3V3 through the first resistor R1. The protection circuit D2 is a freewheeling diode, which provides a current freewheeling loop when the DO is connected to an inductive device. TVS1 provides voltage spike surge protection. The fifth resistor R5 is the output current limiting configuration resistor of chip U1, and the over-current protection current point of U1 is related to the resistance value of this resistor.

[0073] In specific embodiments, as shown in Figure 3 The signal energy discharge module 12 includes a third control circuit Q4, a first discharge circuit D1, a second discharge circuit Q3, a third discharge circuit R12, a seventh resistor R7, a ninth resistor R9, a tenth resistor R10, an eleventh resistor R11, and a fourteenth resistor R14, wherein:

[0074] The first end of the first discharge circuit D1 is connected to the second end of the signal energy discharge module 12 and the second end of the signal output module 11, the second end of the first discharge circuit D1 is connected to the fifth pin, the sixth pin, the seventh pin and the eighth pin of the second discharge circuit Q3, and the third end of the signal energy discharge module 12 is connected to the first end of the signal voltage feedback module 13, the first pin, the second pin and the third pin of the second discharge circuit Q3 are connected, and the common end is connected to one end of the third discharge circuit R12, the other end of the third discharge circuit R12 is grounded;

[0075] One end of the fourteenth resistor R14 is connected to the second pin of the microprocessor 2 as the first end of the signal energy discharge module 12, the other end is connected to the gate of the third control circuit Q4, and the common end is connected to the power supply VCC_3V3 through the ninth resistor R9;

[0076] The source of the third control circuit Q4 is connected with the power supply VCC_DO through the seventh resistor R7, the common end is connected with one end of the tenth resistor R10, the drain of the third control circuit Q4 is grounded, and the other end of the tenth resistor R10 is connected with the fourth pin of the second discharge circuit Q3, and the common end is grounded through the eleventh resistor R11.

[0077] In specific embodiments, as shown in Figure 3 The first discharge circuit is a discharge diode D1, the second discharge circuit is an NMOS switch tube Q3, and the third discharge circuit is a discharge resistor R12.

[0078] It should be noted that, as shown in Figure 3 The above-mentioned signal energy discharge module is mainly composed of a control circuit Q4, discharge circuits D1, Q3 and R12. When the system is powered on, the MCU has not yet worked, Q4 is turned on to GND due to the pull-up of the ninth resistor R9, that is, the gate of Q3 is connected to GND through R10, so the NMOS tube Q3 is not turned on, and the module is in the default closed state when the system is powered on. Only when the MCU controls the DO to be closed, the microcontroller controls DO_TEST_Ctrl to be low, and the voltage division of the fourteenth resistor R14 is not enough to turn on Q4, so that Q3 is turned on through the voltage division of the seventh resistor R7, the tenth resistor R10 and the eleventh resistor R11, and the DO discharges energy through the discharge resistor R12.

[0079] In specific embodiments, as shown in Figure 4 The signal voltage feedback module 13 includes a sixth resistor R6, an eighth resistor R8 and a thirteenth resistor R13, wherein:

[0080] One end of the sixth resistor R6 is connected with the third end of the signal energy discharge module 12 as the first end of the signal voltage feedback module 13, the other end of the sixth resistor R6 is connected with one end of the eighth resistor R8 and one end of the thirteenth resistor R13 respectively, the other end of the thirteenth resistor R13 is grounded, and the other end of the eighth resistor R8 is connected with the third pin of the microprocessor 2 as the second end of the signal voltage feedback module 13.

[0081] Through the above description, the structure of the output state detection circuit of the digital level signal provided by the embodiment of the application can be referred to as a whole. Figure 5

[0082] ​The embodiment of the present application provides an output state detection circuit of a digital level signal, which can detect and trigger a fault in advance, reduce a safety risk, and increase an energy discharge loop, so that bus energy is discharged within a specified time, and if it is detected that the voltage of the digital level signal does not drop to a set value within the specified time, a fault state is triggered, so that the whole personnel detection protection loop responds in time, and the fault can be detected in advance.

[0083] On the basis of the output state detection circuit of the digital level signal provided in the above, the embodiment of the present application further discloses an output state detection method of a digital level signal, which periodically closes an output signal for a short time to test whether the output of the control signal can be normally closed within a specified time.

[0084] It should be noted that the output state detection method of the digital level signal can be divided into self-detection at state switching and periodic self-detection, please refer to Figure 6 for the self-detection at state switching, the purpose is to ensure that the switching can be successful within a specified time, and if the switching is not successful, a fault state is entered. As shown in Figure 6 the self-detection process at state switching includes:

[0085] whether there is personnel close to the robot is detected by a personnel detection sensor;

[0086] If the first control signal output by the microprocessor to the output state detection circuit is low when it is detected that there is personnel close, the closing state of the digital level signal takes effect;

[0087] The second control signal output by the microprocessor to the output state detection circuit is low after waiting for a first set time length, and energy discharge is started.

[0088] The microprocessor acquires the voltage of the digital level signal in real time after waiting for a second set time length, and judges the output state of the digital level signal according to a preset condition.

[0089] The microprocessor acquires the voltage of the digital level signal in real time, and judges the output state of the digital level signal according to a preset condition, including:

[0090] The microprocessor acquires the voltage of the digital level signal in real time, and compares the voltage of the digital level signal with a set power supply voltage; here, the set power supply voltage can be set to 0.1 times the power supply voltage.

[0091] When the off state of the digital level signal is effective, and the voltage of the digital level signal is greater than the set voltage, a first control instruction is sent to the safety main controller, the first control instruction being used to control the safety main controller to execute a safety strategy;

[0092] When the off state of the digital level signal is ineffective, and the absolute value of the difference between the voltage of the digital level signal and the set voltage is greater than the set voltage, a first control instruction is sent to the safety main controller, the first control instruction being used to control the safety main controller to execute a safety strategy;

[0093] When the off state of the digital level signal is ineffective, a second control instruction is sent to the output state detection circuit, the second control instruction being used to control the output state detection circuit to execute a periodic self-check of the digital level signal.

[0094] If the microprocessor outputs a first control signal at a high level to the output state detection circuit when no person is detected to be close, the off state of the digital level signal is ineffective;

[0095] The microprocessor acquires the voltage of the digital level signal in real time after waiting for a third set time length, and judges the output state of the digital level signal according to a second preset condition.

[0096] The microprocessor acquires the voltage of the digital level signal in real time, and judges the output state of the digital level signal according to a second preset condition, including:

[0097] The microprocessor acquires the voltage of the digital level signal in real time, and judges whether the voltage of the digital level signal is within a set power supply voltage range; here, the set power supply voltage range can be set as ±10% of the power supply voltage.

[0098] When the voltage of the digital level signal is not within the set power supply voltage range, a first control instruction is sent to the safety main controller, the first control instruction being used to control the safety main controller to execute a safety strategy;

[0099] When the voltage of the digital level signal is within the set power supply voltage range, a second control instruction is sent to the output state detection circuit, the second control instruction being used to control the output state detection circuit to execute a periodic self-check of the digital level signal.

[0100] During state switching and self-testing, the first set duration TL1 is the delay from the microcontroller outputting the control signal to the actual control of the digital level signal being turned off by the DO driver chip. It is necessary to ensure that the DO is turned off before opening the bleeder circuit. The second set duration TL2 of the bleeder circuit is determined according to design requirements. The second set duration TL2 is related to the load capacitance of the DO line and the bleeder resistor R12 of the bleeder circuit. It should be noted that in actual design, once the second set duration TL2 and the bleeder resistor R12 are determined, the load capacitance of the bus will have a maximum value. If this maximum value is exceeded, the digital level signal cannot reduce its voltage to the specified range within the second set duration TL2. This voltage can be acquired through DO_TEST_AD. This detection method allows for fault detection at the initial stage of equipment installation and commissioning, solving the problem of the digital level signal not reliably turning off within the specified time.

[0101] Furthermore, such as Figure 7 The diagram shows a method for periodically detecting digital level signals during operation, compared to... Figure 6 As can be seen, some self-tests related to state switching are similar. In the system design, when the digital level signal is in the off state, the system is in a non-working state, i.e., a safe state. It is only necessary to periodically check that the output voltage of the digital level signal does not exceed 10% of the power supply voltage. When DO is in the output state, i.e., the system is working, the reliability of DO switching from the output state to the off state needs to be detected in real time. If the inability to shut down normally is only detected when shutdown is required, the reaction time of the entire safety link will be longer.

[0102] Therefore, in this embodiment, the digital level signal is periodically turned off for short periods during normal operation. This off-time is insufficient for the device to detect and stop; theoretically, shorter is better. In this design, the time TL1+TL2+TH2 is defaulted to 1ms. The first set duration TL1 is related to the characteristics of the DO driver chip and is generally around 100us. The second set duration TL2 is related to the DO line's capacitor and bleeder resistor R12. In this embodiment, it is defaulted to 100us, and the bleeder resistor R12 = 10Ω. Calculations show that the DO's load capacitance cannot exceed 2.7uF; otherwise, the digital level signal voltage may not be reduced to 0.1 times the nominal power supply voltage within 500us. The third set duration TH1 is related to the DO driver chip's transmission delay and output rise time, and is designed to be 600us, meaning the entire self-test process is 800us, leaving a 200us margin from the designed 1ms. Therefore, at the receiving end of the digital level signal, pulse signals within 1ms of the digital level signal need to be ignored.

[0103] like Figure 7The periodic self-checking process includes:

[0104] Real-time detection of whether the current is in the DO self-checking time range; if not, end the process;

[0105] If yes, determine whether the DO closed state is effective;

[0106] In the case where the DO closed state is effective, the microprocessor real-time acquires the voltage of the digital level signal, and compares the voltage of the digital level signal with the set power supply voltage; here, the set power supply can be set to 0.1 times the power supply voltage.

[0107] When the voltage of the digital level signal is greater than the set power supply voltage, a first control instruction is sent to the safety main controller, and the first control instruction is used to control the safety main controller to execute the safety strategy.

[0108] When the voltage of the digital level signal is less than or equal to the set power supply voltage, it is determined whether DO_FAULT is low; if yes, a first control instruction is sent to the safety main controller, and the first control instruction is used to control the safety main controller to execute the safety strategy; if not, the process is ended.

[0109] In the case where the DO closed state is not effective, the first control signal output by the output state detection circuit is low, after waiting for a first set time length, the second control signal output by the output state detection circuit is low, after waiting for a second set time length, the second control signal output by the output state detection circuit is high, the voltage of the digital level signal is real-time acquired, the first control signal output by the output state detection circuit is high, and after waiting for a third set time length, the low voltage of the digital level signal is real-time acquired, and the low voltage of the digital level signal is compared with the set power supply voltage; here, the set power supply voltage can be set to 0.1 times the power supply voltage; when the voltage of the digital level signal is greater than the set power supply voltage, a first control instruction is sent to the safety main controller, and the first control instruction is used to control the safety main controller to execute the safety strategy; when the voltage of the digital level signal is less than or equal to the set power supply voltage, the high voltage of the digital level signal is real-time acquired, and it is determined whether the high voltage of the digital level signal is not within the range of the nominal power supply voltage ± 10%; if yes, a first control instruction is sent to the safety main controller, and the first control instruction is used to control the safety main controller to execute the safety strategy; if not, it is determined whether DO_FAULT is low; if yes, a first control instruction is sent to the safety main controller, and the first control instruction is used to control the safety main controller to execute the safety strategy; if not, the process is ended.

[0110] The application also discloses an output state detection system, which comprises Figure 1As shown, the system comprises the output state detection circuit of the digital level signal, the microprocessor and the safety main controller provided in the embodiments of the present application, and the output state detection circuit is connected with the microprocessor and the safety main controller. Figure 1 As shown, the output state detection circuit is connected with the microprocessor and the safety main controller.

[0111] The embodiments of the present application also disclose a robot comprising a robot body and the output state detection system described above arranged on the robot body.

[0112] The detection circuit, the detection method and the related device of the digital level signal provided in the embodiments of the present application can detect whether the digital level signal can be closed within a specified time at the beginning of the detection circuit debugging installation, so as to ensure that the braking distance of the robot is within a specified range. It should be noted that the present application can ensure that the digital level signal is closed within a specified time. For example, when the specified time is designed to be 1ms, assuming that the robot travels at 10m / s, the response time of 1ms only walks 1cm, if the falling edge time of the digital level signal cannot be controlled, because the load capacitance is too large, it takes about 100ms for the digital level signal to drop to the trigger voltage that can be recognized by the back-end system, and in this time, the robot has walked 1M, which is easy to cause danger. At the same time, the present application can also detect whether the digital level signal can be normally closed during the operation of the equipment, so as to ensure the safety response time in an emergency, thereby ensuring that the braking distance of the robot is within a specified range, and avoiding the occurrence of safety accidents.

[0113] The solutions of the present application have been described in detail above with reference to the drawings. In the above embodiments, the description of each embodiment has its own focus, and the parts not described in detail in a certain embodiment can be referred to the relevant description of other embodiments. It should be known by those skilled in the art that the actions and modules involved in the specification are not necessarily required by the present application. In addition, it can be understood that the steps in the embodiments of the present application can be adjusted, combined and reduced in sequence according to actual needs, and the modules in the embodiments of the present application can be combined, divided and reduced according to actual needs.

[0114] The computer software can be coded using any suitable machine code or computer language that can be subject to well- defined and repetitive processing. Note that the computer software can be written in an interpreted language or can be written in a compiled language that is converted into a computer independent intermediate representation code or object code suitable for usage on a variety of computers (i.e., different machines) or that is converted into a proprietary

[0115] Embodiments of the present application have been described above, with the understanding that these embodiments are exemplary only, and not exhaustive, and are not limited to the embodiments disclosed. Many modifications and variations of the described embodiments are possible, without departing from the scope and spirit of the described embodiments. The selection of terms to be used in the description is intended to best explain the principles of the embodiments, practical application, or improvement over the technology in the art, or to enable other ordinary skilled in the art to understand the embodiments disclosed herein.

Claims

1. A digital level signal output state detection circuit, characterized in that, The output status detection circuit is connected to the microprocessor and the security main controller respectively. The output status detection circuit includes: a signal output module, a signal energy discharge module, and a signal voltage feedback module. The signal output module is used to receive a first control signal sent by the microprocessor and output a digital level signal to the safety main controller. The first control signal is a control signal to control the output level signal to be turned off or a control signal to control the output level signal to be turned on. The signal energy discharge module is used to acquire the digital level signal and discharge energy from the digital level signal when it receives the second control signal sent by the microprocessor. The signal voltage feedback module is used to acquire the voltage of the digital level signal in real time and feed the voltage of the digital level signal back to the microprocessor.

2. The output status detection circuit according to claim 1, characterized in that, The first terminal of the signal output module is connected to the first pin of the microprocessor, the second terminal of the signal output module is connected to the digital level signal input module of the safety main controller, the first terminal of the signal energy discharge module is connected to the second pin of the microprocessor, the second terminal of the signal energy discharge module is connected to the second terminal of the signal output module, the third terminal of the signal energy discharge module is connected to the first terminal of the signal voltage feedback module, and the second terminal of the signal voltage feedback module is connected to the third pin of the microprocessor.

3. The output status detection circuit according to claim 2, characterized in that, The signal output module includes: a first control circuit, a second control circuit, a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a first drive circuit, a first protection circuit, a second protection circuit, and a third protection circuit, wherein: The first terminal of the first control circuit is connected to the first terminal of the second control circuit, and is also connected through one end of the fourth resistor. The other end of the fourth resistor is connected to VCC_DO. The second terminal of the second control circuit serves as the first terminal of the signal output module and is connected to the first pin of the microprocessor. The second terminal of the first control circuit is connected to the third terminal of the second control circuit and grounded. The third terminal of the first control circuit is connected to the third terminal of the first drive circuit. The fourth terminal of the first driving circuit is connected to VCC_DO, and the third terminal is connected to VCC_DO through the second resistor; the eighth terminal of the first driving circuit is grounded through the third resistor; the fifth terminal of the first driving circuit serves as the second terminal of the signal output module and is connected to the digital level signal input module of the safety main controller; the sixth terminal of the first driving circuit serves as the feedback terminal of the signal output module and is connected to the second pin of the microprocessor, and the sixth terminal of the first driving circuit is connected to the power supply VCC_3V3 through the first resistor; the seventh terminal of the first driving circuit is grounded through the fifth resistor; the ninth terminal of the first driving circuit is grounded. The first terminal of the first protection circuit, the first terminal of the second protection circuit, and the first terminal of the third protection circuit are connected together, and their common terminal is connected to the fifth terminal of the first driving circuit; the second terminal of the first protection circuit, the second terminal of the second protection circuit, and the second terminal of the third protection circuit are connected together, and their common terminal is grounded.

4. The output status detection circuit according to claim 3, characterized in that, The first protection circuit is a capacitor.

5. The output status detection circuit according to claim 3, characterized in that, The second protection circuit is a freewheeling diode.

6. The output status detection circuit according to claim 3, characterized in that, The third protection circuit is a transient diode.

7. The output state detection circuit according to claim 2, characterized in that, The signal energy discharge module includes: a third control circuit, a first discharge circuit, a second discharge circuit, a third discharge circuit, a seventh resistor, a ninth resistor, a tenth resistor, an eleventh resistor, and a fourteenth resistor, wherein: The first terminal of the first discharge circuit is connected to the second terminal of the signal output module as the second terminal of the signal energy discharge module. The second terminal of the first discharge circuit is connected to the fifth, sixth, seventh and eighth pins of the second discharge circuit, and is connected to the first terminal of the signal voltage feedback module as the third terminal of the signal energy discharge module. The first, second and third pins of the second discharge circuit are connected, and their common terminal is connected to one end of the third discharge circuit. The other end of the third discharge circuit is grounded. One end of the fourteenth resistor serves as the first end of the signal energy discharge module and is connected to the second pin of the microprocessor. The other end is connected to the gate of the third control circuit, and its common terminal is connected to the power supply VCC_3V3 through the ninth resistor. The first terminal of the third control circuit is connected to the power supply VCC_DO through the seventh resistor, and its common terminal is connected to one end of the tenth resistor. The second terminal of the third control circuit is grounded, and the other end of the tenth resistor is connected to the fourth pin of the second bleeder circuit. Its common terminal is grounded through the eleventh resistor.

8. The output status detection circuit according to claim 7, characterized in that, The first discharge circuit is a discharge diode.

9. The output status detection circuit according to claim 7, characterized in that, The second discharge circuit is an NMOS switch.

10. The output state detection circuit according to claim 7, characterized in that, The third bleeder circuit is a bleeder resistor.

11. The output state detection circuit according to claim 1, characterized in that, The signal voltage feedback module includes: a sixth resistor, an eighth resistor, and a thirteenth resistor, wherein: One end of the sixth resistor is connected to the third end of the signal energy discharge module as the first end of the signal voltage feedback module. The other end of the sixth resistor is connected to one end of the eighth resistor and one end of the thirteenth resistor. The other end of the thirteenth resistor is grounded. The other end of the eighth resistor is connected to the third pin of the microprocessor as the second end of the signal voltage feedback module.

12. A method for detecting the output state of a digital level signal, characterized in that, Based on an output status detection system, the system includes: an output status detection circuit for a digital level signal as described in any one of claims 1-11, a microprocessor, and a security main controller, wherein the output status detection circuit is connected to the microprocessor and the security main controller respectively, and the method includes: When an obstacle is detected approaching, the microprocessor outputs a first control signal to the output state detection circuit at a low level, and the digital level signal is turned off. The second control signal output by the microprocessor to the output status detection circuit is low, which initiates energy discharge. The microprocessor acquires the voltage of the digital level signal in real time and determines the output state of the digital level signal according to preset conditions.

13. The method according to claim 12, characterized in that, The microprocessor acquires the voltage of the digital level signal in real time and determines the output state of the digital level signal according to preset conditions, including: The microprocessor acquires the voltage of the digital level signal in real time and compares the voltage of the digital level signal with the set power supply voltage. When the digital level signal is in the off state and the voltage of the digital level signal is greater than the set voltage, a first control command is sent to the security main controller. The first control command is used to control the security main controller to execute the security policy. When the off state of the digital level signal fails, and the absolute value of the difference between the voltage of the digital level signal and the set voltage is greater than the set voltage, a first control command is sent to the safety main controller. The first control command is used to control the safety main controller to execute the safety policy. When the off state of the digital level signal fails, a second control command is sent to the output state detection circuit. The second control command is used to control the output state detection circuit to perform periodic self-test of the digital level signal.

14. The method according to claim 12, characterized in that, Also includes: When no obstacle is detected approaching, the microprocessor outputs a first control signal to the output state detection circuit at a high level, thus disabling the off state of the digital level signal. The microprocessor acquires the voltage of the digital level signal in real time and determines the output state of the digital level signal according to the second preset condition.

15. The method according to claim 14, characterized in that, The microprocessor acquires the voltage of the digital level signal in real time and determines the output state of the digital level signal according to a second preset condition, including: The microprocessor acquires the voltage of the digital level signal in real time and determines whether the voltage of the digital level signal is within the set power supply voltage range. When the voltage of the digital level signal is not within the set power supply voltage range, a first control command is sent to the safety main controller. The first control command is used to control the safety main controller to execute the safety policy. When the voltage of the digital level signal is within the set power supply voltage range, a second control command is sent to the output status detection circuit. The second control command is used to control the output status detection circuit to perform periodic self-test of the digital level signal.

16. An output status detection system, characterized in that, The system includes: an output status detection circuit for a digital level signal as described in any one of claims 1-11, a microprocessor, and a security main controller, wherein the output status detection circuit is connected to the microprocessor and the security main controller respectively.

17. A robot, characterized in that, include: The robot body and the output state detection system as described in claim 16, which is mounted on the robot body.

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