A sine-cosine encoder signal processing device compatible with multiple protocols and types

Abstract

The present invention relates to a sine-cosine encoder signal processing device compatible with multiple protocols and multiple types. The device is compatible with multiple protocols and multiple types of sine-cosine encoder signals, and uses different signal paths to process sine-cosine encoder signals to obtain high-resolution position information. It solves the problem that different encoders in the application system need to be connected to different types of encoder signal processing devices, and the circuits are complex and difficult to disconnect. The device includes an encoder signal input interface, an electrical signal processing circuit, and a single-chip general-purpose processor. The electrical signal processing circuit includes a reference point signal processing circuit, an incremental sine-cosine signal processing circuit, a single-turn sine-cosine signal processing circuit, a synchronous serial signal processing circuit, and an asynchronous serial signal processing circuit. The single-chip general-purpose processor processes the input signal through different signal paths to obtain cycle counting information, position subdivision information, and single-turn absolute position information, and obtains high-resolution real-time position information after splicing and integration.

Description

Technical Field

[0001] The present invention relates to the fields of numerically controlled machine tools, robots and servo control technology, and in particular to a sine-cosine encoder signal processing device compatible with multiple protocols and types. Background Art

[0002] Photoelectric encoders are sensors that convert mechanical geometric displacement into electrical signals such as pulses or digital quantities. They are widely used in industrial fields such as CNC machine tools, robots, and servo control technology to obtain position and speed information.

[0003] The sine-cosine encoder obtains high-resolution position information by performing specific subdivision operations on the output sine-cosine signals. Compared with the square wave incremental sine-cosine encoder, it can obtain more detailed position information under the same physical scale line, and the resolution of the operation speed is higher. The rotation speed is not affected by the signal frequency. Therefore, it is widely used in the CNC machine tool industry.

[0004] When the sine-cosine encoder is powered on, it is necessary to first obtain the initial position information of the rotor. This can be achieved through different design technologies. The single-reference point or multi-reference sine-cosine signal encoder obtains the single-turn absolute position information based on the reference point Z signal, while some modern encoders use a serial protocol interface to directly obtain the single-turn absolute position information by parsing the serial protocol signal. These lead to differences in sine-cosine encoders, and the signals output by different sine-cosine encoders are also very different. Therefore, in the application system, different types of encoder signal processing devices need to be connected to process the encoder signals, which makes the hardware circuit more complicated and inconvenient to use. Summary of the invention

[0005] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a sine-cosine encoder signal processing device that is compatible with multiple protocols and multiple types. The device is compatible with multiple protocols and multiple types of sine-cosine encoder signals. According to the software parameter configuration of the signal type selection module, different signal paths are used to process the sine-cosine encoder signals, thereby obtaining high-resolution position information. This effectively solves the problem that different encoders in the application system need to be connected to different types of encoder signal processing devices, simplifies the hardware circuit, and is easy to use.

[0006] The invention discloses a sine-cosine encoder signal processing device compatible with multiple protocols and types, comprising an encoder signal input interface, an electric signal processing circuit and a single-chip general-purpose processor; the encoder signal input interface is connected to the electric signal processing circuit, and the electric signal processing circuit is connected to the single-chip general-purpose processor.

[0007] The encoder signal input interface is used to connect to the sine-cosine encoder and obtain the position signal output by it. The encoder signal input interface supports the access to the encoder incremental sine-cosine AB signal, reference point Z signal, single-turn sine-cosine CD signal, synchronous serial protocol signal and asynchronous serial protocol signal; the electrical signal processing circuit includes a reference point signal processing circuit, an incremental sine-cosine signal processing circuit, a single-turn sine-cosine signal processing circuit, a synchronous serial signal processing circuit and an asynchronous serial signal processing circuit, which are connected to the encoder signal input interface and process and adjust the input reference point Z signal, incremental sine-cosine AB signal, single-turn sine-cosine CD signal and serial protocol signal; the single-core A general-purpose processor is connected to the electrical signal processing circuit, including a quadruple frequency unit, an analog-to-digital conversion unit, a synchronous serial port unit, an asynchronous serial port unit, a cycle counting module, a position subdivision module, a single-turn position protocol parsing module, a single-turn absolute high-resolution position information acquisition module and an encoder signal type selection module. According to the software parameter configuration of the encoder signal type selection module, different signal paths are selected to process the signal sent by the above-mentioned electrical signal processing circuit, so as to obtain cycle counting information, position subdivision information and single-turn absolute position information, and then the single-turn absolute high-resolution position information acquisition module is used to splice and integrate the above information to obtain accurate real-time position information.

[0008] The above-mentioned electrical signal processing circuit is composed of an operational amplifier module, a comparator module, a voltage reference module and an RS485 interface chip; the operational amplifier module filters and amplifies the input differential sine and cosine signals, and conditions them into single-ended sine and cosine signals, and the single-ended sine and cosine signals use the voltage provided by the voltage reference module as the center level; the comparator module compares the single-ended sine and cosine signals with the voltage provided by the reference voltage to obtain a square wave signal, and the processing of the reference point signal is to directly compare the differential reference point signal to obtain a square wave signal; the voltage reference module provides a reference voltage for the operational amplifier module and the comparator module; the RS485 interface chip is controlled by the serial port unit of the single-chip general processor and the single-turn position protocol parsing module to send and receive data; different module combinations constitute the reference point signal processing circuit, the incremental sine and cosine signal processing circuit, the single-turn sine and cosine signal processing circuit, the synchronous serial protocol signal processing circuit and the asynchronous serial signal processing circuit, and the software parameter configuration of the module can be selected according to the signal type, and different signal processing circuits can be selected to process the various signals input by the encoder signal input interface.

[0009] The single-chip processor processes the square wave signal output by the comparator module and the single-ended sine and cosine signals output by the operational amplifier module to obtain single-turn absolute position information, position subdivision information and cycle count information, which are then spliced ​​and integrated through the single-turn absolute high-resolution position information acquisition module to obtain high-resolution position information.

[0010] Compared with the prior art, the beneficial effects of the present invention are: the present invention provides a signal processing device that is compatible with and can process multiple protocols and multiple types of sine-cosine encoder signals, supports access to multiple protocols and multiple types of sine-cosine encoder signals, has flexible software parameter configuration, can realize the processing of multiple protocols and multiple types of sine-cosine encoder signals and the acquisition of position information, and has strong practicality. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a structural schematic diagram of a sine-cosine encoder signal processing device compatible with multiple protocols and types of the present invention.

[0012] Figure 2 Schematic diagram of a CDABZ (single reference point and multi-reference point ABZ) sine-cosine encoder signal processing circuit according to an embodiment of the present invention.

[0013] Figure 3 The present invention is a schematic diagram of a synchronous serial protocol sine-cosine encoder signal processing circuit according to an embodiment of the present invention.

[0014] Figure 4 The present invention is a schematic diagram of an asynchronous serial protocol sine-cosine encoder signal processing circuit according to an embodiment of the present invention. DETAILED DESCRIPTION

[0015] like Figure 1As shown, a multi-protocol and multi-type sine-cosine encoder signal processing device of the present invention includes an encoder signal input interface 1, an electrical signal processing circuit 2, and a single-chip general-purpose processor 3. The encoder signal input interface 1 is connected to the electrical signal processing circuit 2, and the electrical signal processing circuit 2 is connected to the single-chip general-purpose processor 3. The encoder signal input interface 1 is used to obtain the position signal connected and output by the sine-cosine encoder. The encoder signal input interface 1 supports access to the encoder incremental sine-cosine AB signal, reference point Z signal, single-turn sine-cosine CD signal, synchronous serial protocol signal, and asynchronous serial protocol signal; the electrical signal processing circuit 2 includes a reference point signal processing circuit, an incremental sine-cosine signal processing circuit, a single-turn sine-cosine signal processing circuit, a synchronous serial signal processing circuit, and an asynchronous serial signal processing circuit, and processes and adjusts the reference point Z signal, incremental sine-cosine AB signal, single-turn sine-cosine CD signal, and serial protocol signal input by the encoder signal input interface 1; The single-chip general-purpose processor 3 includes a quadruple frequency unit, an analog-to-digital conversion unit, a synchronous serial port unit, an asynchronous serial port unit, a cycle counting module, a position subdivision module, a single-turn position protocol parsing module, a single-turn absolute high-resolution position information acquisition module and an encoder signal type selection module. According to the software parameter configuration of the encoder signal type selection module, different signal paths are selected to process the signal sent by the above-mentioned electrical signal processing circuit 2, so as to obtain cycle counting information, position subdivision information and single-turn absolute position information, and then the single-turn absolute high-resolution position information acquisition module is used to splice and integrate the above information to obtain accurate real-time position information.

[0016] Several sine-cosine encoder signal processing and position acquisition methods are described below in conjunction with the accompanying drawings.

[0017] 1. CDABZ sine-cosine encoder, single reference point and multi-reference point ABZ sine-cosine encoder signal processing:

[0018] Figure 2In the embodiment shown, the electrical signal processing circuit 201 includes an operational amplifier module, a voltage reference module and a comparator module, and the CDABZ encoder outputs a differential single-turn sine-cosine CD signal, a differential incremental sine-cosine AB signal and a differential reference point Z signal. The processing method is as follows: the differential reference point Z signal is processed by the comparator module of the electrical signal processing circuit 201 to obtain a square wave signal, which is sent to the quadruple frequency unit of the single-chip general-purpose processor 3; the differential sine-cosine CD signal is filtered and amplified by the operational amplifier module of the electrical signal processing circuit 201, conditioned into a single-ended sine-cosine CD signal, and sent to the analog-to-digital conversion unit of the single-chip general-purpose processor 3; the differential sine-cosine AB signal is filtered and amplified by the operational amplifier module of the electrical signal processing circuit 201, conditioned into a single-ended sine-cosine AB signal, which is directly sent to the analog-to-digital conversion unit of the single-chip general-purpose processor 3 on the one hand, and sent to the comparator module of the electrical signal processing circuit 201 on the other hand, and is compared with the reference voltage of the electrical signal processing circuit 201 to obtain an orthogonal square wave signal, which is sent to the quadruple frequency unit of the single-chip general-purpose processor 3. After the initial power-on, the single-chip general processor 3 samples and quantizes the single-ended sine and cosine CD signal and subdivides the approximate single-turn absolute position information, and samples and quantizes the single-ended sine and cosine AB signal and subdivides the position subdivision information. The two cooperate to obtain the approximate high-resolution single-turn absolute position information. After the encoder runs through the reference point Z, it is corrected to the accurate high-resolution single-turn absolute position information. The quadruple frequency unit and the cycle counting module of the single-chip general processor 3 count the quadruple frequency cycle of the square wave signal output by the comparator module of the electrical signal processing circuit 201, and correct the cycle quadruple frequency count value according to the current accurate position to obtain accurate cycle counting information. Subsequently, the cycle counting information and the position subdivision information can be directly spliced ​​and integrated into the real-time position information. The processing method of the single reference point and multi-reference point ABZ sine and cosine encoder is similar to that of the CDABZ sine and cosine encoder, except that these two encoders have no CD signal and obtain the approximate single-turn absolute position information with the initial power-on position as the zero point; the multi-reference point ABZ sine and cosine encoder is different in that the cycle counting information is obtained by counting the distance between the two reference point Z signals that have been rotated the closest.

[0019] 2. Synchronous serial protocol sine and cosine encoder signal processing:

[0020] Figure 3In the embodiment shown, the electrical signal processing circuit 202 includes an operational amplifier module, a voltage reference module, a comparator module and an RS485 interface chip circuit. The synchronous serial protocol sine and cosine encoder outputs differential clock and data signals in addition to the differential sine and cosine AB signals. The processing method is that the differential clock and data signals are sent to the synchronous serial port unit of the single-chip general processor 3 through the RS485 interface chip circuit of the synchronous serial protocol signal processing circuit 202; the differential sine and cosine AB signals are filtered and amplified by the operational amplifier of the electrical signal processing circuit 202, and conditioned into single-ended sine and cosine AB signals, which are directly sent to the analog-to-digital conversion unit of the single-chip general processor 3 on the one hand, and sent to the comparator module of the electrical signal processing circuit 202 on the other hand, and compared with the reference voltage of the electrical signal processing circuit 202 to obtain an orthogonal square wave signal, which is sent to the quadrature unit of the single-chip general processor 3. After the initial power-on, the single-turn position analysis module and synchronous serial port unit of the single-chip general processor 3 control the RS485 interface chip of the electrical signal processing circuit 202 to send and receive data according to the protocol of the selected encoder type, and analyze the single-turn absolute position information. The analog-to-digital conversion unit and position subdivision module of the single-chip general processor 3 sample and quantize the single-ended sine and cosine AB signal and subdivide the high-resolution position information, which is integrated with the single-turn absolute position information to obtain the high-resolution single-turn absolute position information. According to the current single-turn position information, the periodic quadruple frequency count value is corrected to obtain the periodic count information, which can be directly spliced ​​and integrated into the real-time position information according to the periodic count information and the position subdivision information. The synchronous serial protocol analysis module selects the analyzable protocols EnDat, BISS, FeeDat, and SSI according to the encoder signal type. If other synchronous serial protocols need to be analyzed, the single-chip general processor 3 can be modified to add programs, and the hardware already supports it.

[0021] 3. Asynchronous serial protocol sine-cosine encoder signal processing:

[0022] Figure 4 In the illustrated embodiment, the electrical signal processing circuit 203 includes an operational amplifier module, a voltage reference module, a comparator module, and an RS485 interface chip circuit. The processing flow of the asynchronous serial protocol sine-cosine encoder is similar to the processing flow of the synchronous serial protocol sine-cosine encoder above, except that the asynchronous serial port unit of the single-chip general processor 3 is used. The asynchronous serial protocol parsing module can parse the protocol HIPERFSCE. If other asynchronous serial protocols need to be parsed, the software of the single-chip general processor 3 can be modified to add a program, and the hardware already supports it.

Claims

1. A sine-cosine encoder signal processing device compatible with multiple protocols and types, comprising an encoder signal input interface, an electrical signal processing circuit and a single-chip general-purpose processor; the encoder signal input interface is connected to the electrical signal processing circuit, and the electrical signal processing circuit is connected to the single-chip general-purpose processor, characterized in that: The encoder signal input interface includes the encoder incremental sine and cosine AB signal input interface, the reference point Z signal input interface, the single-turn sine and cosine CD signal input interface, the synchronous serial protocol signal input interface and the asynchronous serial protocol signal input interface, which supports the access of multi-protocol and multi-type sine and cosine encoder signals; The electrical signal processing circuit includes a reference point signal processing circuit, an incremental sine and cosine signal processing circuit, a single-turn sine and cosine signal processing circuit, a synchronous serial protocol signal processing circuit, and an asynchronous serial protocol signal processing circuit, and processes and adjusts the electrical signal input from the encoder signal input interface through different circuits; The single-chip general-purpose processor includes a quadruple frequency unit, an analog-to-digital conversion unit, a synchronous serial port unit, an asynchronous serial port unit, a cycle counting module, a position subdivision module, a single-turn position protocol analysis module, a single-turn absolute high-resolution position information acquisition module, and an encoder signal type selection module. According to the software parameter configuration of the encoder signal type selection module, different signal paths are selected to process the signal input from the encoder signal processing interface, and different sine and cosine encoder signals are processed to finally obtain accurate high-resolution position information; The electrical signal processing circuit is composed of an operational amplifier module, a comparator module, a voltage reference module and an RS485 interface chip; wherein the operational amplifier module, the comparator module and the voltage reference module are used to process the encoder incremental sine and cosine AB signals, the single-turn sine and cosine CD signals and the reference point Z signal; the RS485 interface chip is controlled by a synchronous serial port unit or an asynchronous serial port unit of a single-chip general-purpose processor to receive and transmit differential data signals; The sine-cosine encoder signal processing device processes the differential single-turn sine-cosine CD signal, the differential incremental sine-cosine AB signal and the differential reference point Z signal output by the CDABZ encoder in the following manner: the differential reference point Z signal is subjected to a comparator to obtain a square wave signal, which is sent to the quadruple frequency unit of the single-chip general-purpose processor; the differential sine-cosine CD signal is filtered and amplified by an operational amplifier module, conditioned into a single-ended sine-cosine CD signal, and sent to the analog-to-digital conversion unit of the single-chip general-purpose processor; the differential sine-cosine AB signal is filtered and amplified by an operational amplifier module, conditioned into a single-ended sine-cosine AB signal, which is directly sent to the analog-to-digital conversion unit of the single-chip general-purpose processor on the one hand, and sent to the comparator module on the other hand, and compared with the reference voltage to obtain an orthogonal square wave signal, which is sent to the quadruple frequency unit of the single-chip general-purpose processor; after initial power-on, the single-chip general-purpose processor samples and quantizes the single-ended sine-cosine CD signal and subdivides the approximate single-turn absolute position information At the same time, the single-ended sine and cosine AB signals are sampled and quantized and the position segmentation information is subdivided. The two cooperate to obtain the approximate high-resolution single-turn absolute position information. After the encoder runs through the reference point Z, it is corrected to the accurate high-resolution single-turn absolute position information. The quadruple frequency unit and the cycle counting module count the quadruple frequency cycle of the square wave signal output by the comparator module, and correct the cycle quadruple frequency count value according to the current accurate position to obtain accurate cycle counting information. Subsequently, the cycle counting information and position segmentation information can be directly spliced ​​and integrated into the real-time position information; the processing method of the single reference point and multi-reference point ABZ sine and cosine encoder is similar to that of the CDABZ sine and cosine encoder, except that these two encoders have no CD signal, and the initial power-on position is used as the zero point to obtain the approximate single-turn absolute position information; the difference between the multi-reference point ABZ sine and cosine encoder is that the cycle counting information is obtained by counting the distance between the two reference point Z signals that have passed the closest rotation; The processing flow of the sine-cosine encoder signal processing device for the asynchronous serial protocol sine-cosine encoder is similar to that for the synchronous serial protocol sine-cosine encoder, the only difference being the use of an asynchronous serial port unit of a single-chip general-purpose processor; the asynchronous serial protocol parsing module can parse the protocol HIPERFSCE, and if other asynchronous serial protocols need to be parsed, the single-chip general-purpose processor software can be modified to add a program, which is already supported by the hardware.

2. The multi-protocol and multi-type sine-cosine encoder signal processing device according to claim 1, characterized in that: The processing method for the synchronous serial protocol sine and cosine encoder signal is as follows: the differential clock and data signal are sent to the synchronous serial port unit of the single-chip general-purpose processor through the RS485 interface chip circuit; the differential sine and cosine AB signal is filtered and amplified by the operational amplifier and conditioned into a single-ended sine and cosine AB signal, which is directly sent to the analog-to-digital conversion unit of the single-chip general-purpose processor on the one hand, and sent to the comparator module on the other hand. After comparison with the reference voltage, an orthogonal square wave signal is obtained and sent to the quadrature frequency unit of the single-chip general-purpose processor; after initial power-on, the single-turn position analysis module and the synchronous serial port unit of the single-chip general-purpose processor control the RS485 interface chip to send and receive data according to the protocol of the selected encoder type, and analyze The single-turn absolute position information is output. The analog-to-digital conversion unit and position subdivision module of the single-chip general-purpose processor sample and quantize the single-ended sine and cosine AB signals and subdivide the high-resolution position information, which is integrated with the single-turn absolute position information to obtain the high-resolution single-turn absolute position information. The periodic quadruple frequency count value is corrected according to the current single-turn position information to obtain the periodic count information, which can be directly spliced ​​and integrated into the real-time position information based on the periodic count information and the position subdivision information. The synchronous serial protocol parsing module selects the parseable protocols EnDat, BISS, FeeDat, and SSI according to the encoder signal type. If other synchronous serial protocols need to be parsed, the single-chip general-purpose processor software can be modified to add programs, and the hardware already supports it.

3. A multi-protocol and multi-type sine-cosine encoder signal processing device according to claim 1 or 2, characterized in that: The single-chip general-purpose processor is a DSP chip processor or an ARM chip processor.

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