Safety torque sensor detection circuit

Abstract

The utility model discloses a safety type torque sensor detection circuit, which relates to the technical field of torque sensors, and comprises two detection channels, each detection channel comprises a sensor bridge, a diagnosis circuit and a diagnosis driving circuit connected with the sensor bridge and the diagnosis circuit; the serial digital interface circuit is respectively connected with the diagnosis driving circuit and the sensor bridge and diagnosis circuit in the two detection channels; and the functional safety interface circuit is connected with the serial digital interface circuit and comprises two microcontrollers which are connected with each other. According to the utility model, two paths of detection channels which are electrically isolated from each other are arranged, and the system can reach a higher safety level through detection and diagnosis of two paths of signals.

Description

Technical Field

[0001] The utility model relates to the technical field of torque sensors, and particularly to a safety-type torque sensor detection circuit. Background Art

[0002] Torque sensors are widely used in many fields, such as industrial automation, automotive engine control, robotics, etc. Especially in robotic applications, torque sensors can monitor torque in real time, provide accurate load information for system control, and help improve the accuracy of robot motion control. However, existing torque sensors do not meet the safety level requirements, cannot be applied to industrial robots with high safety requirements, and are even less applicable to collaborative robots with higher safety level requirements. Therefore, further improvement and perfection are needed.

[0003] In traditional torque sensors, the sensing element usually consists of a contact sensor such as a strain gauge or a Hall element to form a Wheatstone bridge, and the signal is conditioned and amplified by a peripheral signal processing circuit to complete the detection of torque. Once there is a problem in any link from the sensor to the signal output terminal, it will affect the detection result. At the lightest, it will cause control deviation, and at the heaviest, it will cause problems in functions such as control and safety protection that rely on torque, resulting in a series of safety risks. Summary of the Utility Model

[0004] The technical problem to be solved by the utility model is to overcome the shortcomings of the prior art and provide a safety-type torque sensor detection circuit.

[0005] To solve the above technical problems, the technical solution of the utility model is as follows:

[0006] A safety-type torque sensor detection circuit, characterized by comprising:

[0007] Detection channels, two are provided, and each detection channel includes a sensor bridge, a diagnostic circuit, and a diagnostic drive circuit connected to the sensor bridge and the diagnostic circuit;

[0008] A serial digital interface circuit, which is respectively connected to the diagnostic drive circuits in the two detection channels and the sensor bridge and the diagnostic circuit;

[0009] A functional safety interface circuit, connected to the serial digital interface circuit, and includes two microcontrollers connected to each other;

[0010] Wherein, both of the two microcontrollers are used to transmit control instructions to the diagnostic drive circuit through the serial digital interface circuit;

[0011] The diagnostic drive circuit is used to receive the control instructions transmitted by the host computer and change the range of the torque signal output by itself;

[0012] The sensor bridge and the diagnostic circuit are used to detect torque signals, convert the detected torque signals into electrical signals, and transmit them to the host computer through the serial digital interface circuit;

[0013] The two microcontrollers are also used to receive the torque signals transmitted by the two detection channels and perform cross-checking.

[0014] As a preferred embodiment of the safety torque sensor detection circuit of the present invention, each of the detection channels further includes a filtering and amplifying circuit connected between the sensor bridge and the diagnostic circuit and the serial digital interface circuit, and the filtering and amplifying circuit is used to filter and amplify the torque signals output by the sensor bridge and the diagnostic circuit.

[0015] As a preferred embodiment of the safety torque sensor detection circuit of the present invention, each of the detection channels further includes an analog-to-digital conversion circuit connected between the filtering and amplifying circuit and the serial digital interface circuit, and the analog-to-digital conversion circuit is used to convert the torque analog signal after passing through the filtering and amplifying circuit into a digital signal.

[0016] As a preferred embodiment of the safety torque sensor detection circuit of the present invention, each detection channel further includes a parameter storage and temperature detection circuit, and the parameter storage and temperature detection circuit is connected to the serial digital interface circuit;

[0017] The parameter storage and temperature detection circuit is used to store sensor calibration parameters and temperature compensation parameters, and collect real-time temperature data, and the host computer is used to compensate the collected torque signals according to the stored parameters and the real-time temperature data.

[0018] As a preferred embodiment of the safety torque sensor detection circuit of the present invention, the parameter storage and temperature detection circuit includes a programmable read-only memory and a temperature sensor connected to the I2C interface.

[0019] As a preferred embodiment of the safety torque sensor detection circuit of the present invention, the sensor bridge and the diagnostic circuit include a Wheatstone bridge circuit.

[0020] The beneficial effects of the present invention are:

[0021] (1) The present invention provides two electrically isolated detection channels. By performing two-channel signal detection and diagnosis, the system can achieve a higher safety level.

[0022] (2) Each detection channel in the present utility model further includes a parameter storage and temperature detection circuit. The parameter storage and temperature detection circuit is used to store the sensor calibration parameters and temperature compensation parameters, and collect real-time temperature data. The host computer can compensate the torque signal collected by the sensor bridge and the diagnostic circuit according to the stored sensor calibration parameters, temperature compensation parameters and real-time temperature data to achieve higher detection accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions of the embodiments of the present utility model, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained according to these drawings.

[0024] Figure 1 Schematic diagram of the safety torque sensor detection circuit provided by the present utility model;

[0025] Wherein: 101, sensor bridge and diagnostic circuit; 102, diagnostic drive circuit; 103, filtering and amplifying circuit; 104, analog-to-digital conversion circuit; 105, parameter storage and temperature detection circuit; 106, serial digital interface circuit; 107, functional safety interface circuit; 108, microcontroller. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0026] To make the content of the present utility model easier to be clearly understood, the following further detailed description of the present utility model is made according to the specific embodiments and in conjunction with the drawings.

[0027] Figure 1 Schematic diagram of the safety torque sensor detection circuit provided by the embodiments of the present application. The detection circuit includes two detection channels, a serial digital interface circuit 106, and a functional safety interface circuit 107. Among them, signal detection and diagnosis work are simultaneously carried out through two electrically isolated detection channels, so that the system reaches a higher safety level.

[0028] Specifically, refer to Figure 1 , each detection channel includes a sensor bridge and diagnostic circuit 101, a diagnostic drive circuit 102, a filtering and amplifying circuit 103, and an analog-to-digital conversion circuit 104. In each detection channel, the sensor bridge and diagnostic circuit 101 are connected to the serial digital interface circuit 106 through the filtering and amplifying circuit and the analog-to-digital conversion circuit 104. The sensor bridge and diagnostic circuit 101 are also connected to the serial digital interface circuit 106 through the diagnostic drive circuit 102. The functional safety interface circuit 107 is connected to the serial digital interface circuit 106.

[0029] Among them, the sensor bridge and diagnostic circuit 101 is used to detect the torque signal and convert the detected torque signal into an electrical signal. The filtering and amplification circuit 103 is used to filter and amplify the torque signal output by the sensor bridge and diagnostic circuit 101. The analog-to-digital conversion circuit 104 is used to convert the filtered and amplified torque analog signal into a digital signal, and transmit the torque digital signal to the functional safety interface circuit 107 through the serial digital interface circuit 106. The functional safety interface circuit 107 transmits control instructions to the diagnostic drive circuit 102 through the serial digital interface circuit 106, so that the diagnostic drive circuit 102 changes the range of the torque signal it outputs, thereby changing the torque signal detected by the sensor bridge and diagnostic circuit 101, so as to achieve the purpose of identifying whether the torque signal is normal.

[0030] The functional safety interface circuit 107 is a control unit with a safety redundant architecture, responsible for cross-checking the torque signals of the two detection channels and communicating with the user terminal or the host computer. Among them, the functional safety interface circuit 107 includes two interconnected microcontrollers 108.

[0031] Among them, both of the two microcontrollers 108 are used to transmit control instructions to the diagnostic drive circuit 102 through the serial digital interface circuit 106, so that the diagnostic drive circuit 102 changes the range of the torque signal it outputs. At the same time, the two microcontrollers 108 are also used to receive the torque signals transmitted by the two detection channels respectively and perform cross-checking, so as to make the system reach a higher safety level.

[0032] Preferably, each detection channel further includes a parameter storage and temperature detection circuit 105. The parameter storage and temperature detection circuit 105 is connected to the serial digital interface circuit 106. The parameter storage and temperature detection circuit 105 is used to store the sensor calibration parameters and temperature compensation parameters, and collect real-time temperature data. The host computer can compensate the torque signal collected by the sensor bridge and diagnostic circuit 101 according to the stored sensor calibration parameters, temperature compensation parameters and real-time temperature data, so as to achieve higher detection accuracy.

[0033] It should be noted that when the host computer has the cross-checking function, the functional safety interface circuit 107 part can be not used, and the data of the torque sensor can be directly transmitted through the signal and power interface in the serial digital interface circuit 106 to complete the safe torque detection function.

[0034] In this embodiment, the sensor bridge and diagnostic circuit 101 includes a Wheatstone bridge circuit. The parameter storage and temperature detection circuit 105 includes a programmable read-only memory and a temperature sensor connected to the I2C interface.

[0035] Thus, the technical solution of this application simultaneously performs signal detection and diagnosis through two electrically isolated detection channels, enabling the system to reach a higher safety level.

[0036] In addition to the above embodiments, the present utility model may also have other implementation manners; all technical solutions formed by equivalent substitution or equivalent transformation fall within the protection scope required by the present utility model.

Claims

1. A safety type torque sensor detection circuit, characterized in that: Including: Two detection channels are provided. Each detection channel includes a sensor bridge and a diagnostic circuit (101), and a diagnostic drive circuit (102) connected to the sensor bridge and the diagnostic circuit (101); A serial digital interface circuit (106) is respectively connected to the diagnostic drive circuit (102) and the sensor bridge and diagnostic circuit (101) in the two detection channels; A functional safety interface circuit (107) is connected to the serial digital interface circuit (106) and includes two microcontrollers (108) connected to each other; Among them, both of the two microcontrollers (108) are used to transmit control instructions to the diagnostic drive circuit (102) through the serial digital interface circuit (106); The diagnostic drive circuit (102) is used to receive control instructions transmitted by a host computer and change the range of the torque signal output by itself; The sensor bridge and diagnostic circuit (101) is used to detect a torque signal, convert the detected torque signal into an electrical signal, and transmit it to the host computer through the serial digital interface circuit (106); The two microcontrollers (108) are also used to receive torque signals transmitted by the two detection channels and perform cross-checking.

2. The safety torque sensor detection circuit according to claim 1, characterized in that: Each detection channel further includes a filtering and amplification circuit (103) connected between the sensor bridge and diagnostic circuit (101) and the serial digital interface circuit (106). The filtering and amplification circuit (103) is used to filter and amplify the torque signal output by the sensor bridge and diagnostic circuit (101).

3. The safety torque sensor detection circuit according to claim 2, wherein: Each detection channel further includes an analog-to-digital conversion circuit (104) connected between the filtering and amplification circuit (103) and the serial digital interface circuit (106). The analog-to-digital conversion circuit (104) is used to convert the torque analog signal after passing through the filtering and amplification circuit (103) into a digital signal.

4. The safety type torque sensor detection circuit according to claim 1, characterized in that: Each detection channel further includes a parameter storage and temperature detection circuit (105). The parameter storage and temperature detection circuit (105) is connected to the serial digital interface circuit (106); The parameter storage and temperature detection circuit (105) is used to store sensor calibration parameters and temperature compensation parameters, and collect real-time temperature data. The host computer is used to compensate the collected torque signal according to the saved parameters and the real-time temperature data.

5. The safety torque sensor detection circuit according to claim 4, characterized in that: The parameter storage and temperature detection circuit (105) includes a programmable read-only memory and a temperature sensor connected to an I2C interface.

6. The safety type torque sensor detection circuit according to claim 1, characterized in that: The sensor bridge and diagnostic circuit (101) includes a Wheatstone bridge circuit.

Images