CN213363708U

CN213363708U - Compound angle measurement circuit of multiaxis revolving stage

Info

Publication number: CN213363708U
Application number: CN202022434903.4U
Authority: CN
Inventors: 曾悠兵; 郑文彬; 丁德甫; 曹晓敏
Original assignee: Jiujiang Precision Measuring Technology Research Institute
Current assignee: Jiujiang Precision Measuring Technology Research Institute
Priority date: 2020-10-28
Filing date: 2020-10-28
Publication date: 2021-06-04
Anticipated expiration: 2030-10-28

Abstract

The utility model provides a compound angle measurement circuit of multiaxis revolving stage, this angle measurement circuit includes 3 differential signal converters of the same model, 6 RS485 signal converters of the same model, 1 16 bit level converters, 1 FPGA logic device, 48 bit level converters of the same model, 2 LDO power chip of the same model, a PCI interface chip and PCI golden finger. The circuit can realize the processing, decoding and transmission functions of the grating and encoder angle signals, has the characteristics of no code loss, wide application range and high transmission speed, and can meet the high-precision and high-speed angle measurement requirements of the rotary table of the inertia test equipment on multi-axis and multi-type composite angle sensors.

Description

Compound angle measurement circuit of multiaxis revolving stage

Technical Field

The utility model relates to a compound angle measurement circuit of multiaxis revolving stage, especially a be suitable for the compound high-speed angle measurement circuit of multiaxis of inertia test equipment revolving stage of angle feedback device for encoder and grating.

Background

The grating and the encoder are angle sensitive elements, and are commonly applied to a rotary transformer and a circular induction synchronizer as an angle feedback device in a rotary table of inertia test equipment. The rotary transformer has high adaptability to severe environment, high and low temperature resistance and strong shock vibration resistance, but the precision is lower; the circular induction synchronizer has higher precision, but the installation process is complex, the clearance between the rotor and the stator needs to be strictly controlled, the time drift is difficult to control, and the precision of the circular induction synchronizer can change along with the time; the grating and the encoder adopt advanced photoelectric and digital technologies, have high precision, simple use, convenient installation and small time drift, and are common and ideal angle feedback devices of the turntable of the inertia test equipment in a laboratory environment.

The turntable is an inertia test device used in a laboratory environment, and is an indispensable precision device for calibrating the gyro parameters of an inertia device. The conventional rotary table is generally divided into a single-axis rotary table, a double-axis rotary table, a three-axis rotary table and a five-axis rotary table and is used for providing standard attitude, position, speed information and the like for the gyroscope in a laboratory, so that the calibration of the gyroscope is realized.

In practical application, because the number of the axes of the rotary table is different, the types of the angle feedback devices adopted by each axis are also different, so that the rotary table is different in angle measuring circuits of the encoder and the grating, and currently, the rotary table is more applied, such as a single-axis encoder angle measuring circuit, a single-axis grating angle measuring circuit, a double-axis encoder angle measuring circuit, a double-axis grating angle measuring circuit, a three-axis encoder angle measuring circuit, a three-axis grating angle measuring circuit, a five-axis grating angle measuring circuit and the like.

The angle measuring circuit has the following problems:

1. the angle measuring circuit of a certain type can only be applied to a certain type of specific rotary table;

2. the angle measurement circuit boards are more, so that the design cost and the unreliable risk of the circuit are increased;

3. the angle measurement circuit board has single function and cannot be applied to occasions of multi-type multi-axis composite angle feedback devices;

4. the angle measuring circuit board mostly adopts an ISA interface or an RS232/422 serial interface to carry out data interaction with an upper computer, the transmission speed is slow, the ISA interface cannot be compatible with WIN7 and above systems, and the adaptability is poor.

SUMMERY OF THE UTILITY MODEL

The utility model discloses its aim at provides a compound angle measurement circuit of multiaxis revolving stage, the utility model provides a compound angle measurement circuit of multiaxis revolving stage based on PCI interface is owing to adopted 3 difference signal converter AM26LS32AIDR, 6 RS485 signal converter MAX3485ESA + and a PCI interface chip, the revolving stage condition and the wide fast PCI transmission technology who is high of adaptability that different angle feedback devices are adopted to the different number of axles and every axle of having fully considered, this angle measurement circuit can be in XP, WIN7 and above-mentioned system's PCI interface under realize the compound of multiaxis revolving stage and do not have the parallel high-speed angle measurement function of losing a yard, this application range that has greatly expanded angle measurement circuit has improved transmission speed, can solve the problem that above-mentioned current angle measurement circuit exists well.

The technical scheme adopted for achieving the purpose is that the multi-axis rotary table composite angle measuring circuit comprises an angle measuring circuit board, a three-axis rotary table and an upper computer with a PCI groove, wherein the three-axis rotary table comprises an inner axis angle feedback device, a middle axis angle feedback device and an outer axis angle feedback device, the inner axis angle feedback device is a grating, the outer axis angle feedback device is an encoder, the angle measuring circuit board is characterized by comprising an FPGA (field programmable gate array) logic device, a PCI interface chip, a PCI golden finger and an LDO (low dropout regulator) power supply chip, the angle measuring circuit board is inserted into the PCI groove of the upper computer, encoder signals of an inner axis, a middle axis grating and an outer axis of the three-axis rotary table are connected to the angle measuring circuit board, the angle measuring circuit board comprises the FPGA logic device, the FPGA logic device is connected with an encoder of an outer axis of the three-axis rotary table through 6 RS485 signal converters, the encoder of the outer axis provides angle data later, and after receiving the grating signals of the inner shaft and the middle shaft and the encoder signals of the outer shaft, the FPGA logic device respectively decodes the angles of the grating signals, completes the conversion between the FPGA 3.3V level and the PCI interface chip 5V level through 4 level converters with 8 bits after the decoding is completed, then realizes the PCI transmission protocol through the PCI interface chip, and completes the angle transmission with the upper computer through the PCI golden finger of the angle measuring circuit and the PCI slot of the upper computer, thereby realizing the high-speed and high-precision angle measurement.

Advantageous effects

Compared with the prior art, the utility model has the following advantages.

1. The application range is wide: the device can adapt to the situation that each axis of angle feedback devices are encoders or gratings and the composite angle of the turntable of up to 6 axes is measured in parallel, and can be used in PCI slots of industrial personal computers of XP and WIN7 systems at the same time, unlike the situation that an angle measuring circuit based on an ISA interface can only be used in ISA slots of industrial personal computers of XP systems (WIN 7 and the industrial personal computers have no ISA slots);

2. the angle measurement precision is high: decoding and transmitting angle without missing codes;

3. the transmission speed is fast: the transmission speed can reach 33 Mb/s.

Drawings

The present invention will be described in detail with reference to the accompanying drawings.

Fig. 1 is a logic diagram of the angle measuring circuit in the present invention;

fig. 2 is the angle measuring circuit of the present invention, which comprises a three-axis turntable, an upper computer, an encoder, and an angle feedback system with gratings, and a logic diagram.

Detailed Description

A multi-axis rotary table composite angle measuring circuit comprises an angle measuring circuit board, a three-axis rotary table and an upper computer with a PCI slot, wherein the three-axis rotary table comprises an inner axis angle feedback device which is a grating, a middle axis angle feedback device which is a grating and an outer axis angle feedback device which is an encoder, as shown in figures 1 and 2, the angle measuring circuit board comprises an FPGA (field programmable gate array) logic device, a PCI interface chip, a PCI golden finger and an LDO (low dropout regulator) power supply chip, the angle measuring circuit board is inserted into the PCI slot of the upper computer, encoder signals of the inner axis, the grating of the middle axis and the outer axis of the three-axis rotary table are connected to the angle measuring circuit board, the angle measuring circuit board comprises an FPGA logic device, the FPGA logic device is connected with an encoder of the outer axis of the three-axis rotary table through 6 RS485 signal converters, the encoder of the outer axis gives angle data later, and meanwhile, grating ABZ differential signals of the, the FPGA logic device respectively decodes the angle of the inner shaft, the middle shaft and the outer shaft after receiving the grating signals of the inner shaft and the middle shaft and the encoder signals of the outer shaft, the conversion of the FPGA 3.3V level and the PCI interface chip 5V level is completed through 4 level converters with 8 bits after the decoding is completed, then the PCI transmission protocol is realized through the PCI interface chip, and the angle transmission with an upper computer is completed through a PCI golden finger of an angle measuring circuit and a PCI slot of the upper computer, so that the high-speed and high-precision angle measurement is realized.

The 3 differential signal converters are differential signal converters of the same type, the differential signal converter is AM26LS32AIDR, the 6 RS485 signal converters are RS485 signal converters of the same type, the RS485 signal converter is MAX3485ESA +, the FPGA logic device is EP2C8T144I8N, the PCI interface chip is CH365P, the 4 8-bit level converters are 8-bit level converters of the same type, and the 2 LDO power chips are LDO power chips of the same type.

Examples

The model of the differential signal converter is AM26LS32AIDR, and the model of the RS485 signal converter is MAX3485ESA +. The differential signal converter converts an ABZ differential signal input by a grating into an ABZ single-ended signal, and the RS485 signal converter converts a data signal in an RS485 format input by the encoder into a 3.3V level pulse data signal on one hand and converts a 3.3V level pulse clock signal into a clock signal in an RS485 format on the other hand and outputs the clock signal to the encoder. The combination of 3 differential signal converters and 6 RS485 signal converters can realize the parallel angle signal processing function of up to 6 shafts of the rotary table, and can meet most of application occasions of the conventional rotary table for measuring the angles of the grating and the encoder.

The FPGA logic device is EP2C8T144I8N in model, and is used for carrying out angle counting decoding on 3 paths of grating ABZ signals output by a 16-bit level converter and carrying out angle decoding on encoder data signals input by an RS485 signal converter, so that no-missing-code decoding of a multi-axis encoder and grating angle signals is realized, and meanwhile, 3.3V/5V level conversion is carried out through 4 8-bit level converters and data interaction is carried out with a PCI interface chip.

The PCI interface chip is in a model number of CH365P and is used for converting an encoder and a grating angle signal transmission protocol which are decoded by the FPGA logic device into a PCI protocol. The 8-bit data line, the 8-bit address line, the read-write control line and the interrupt signal line of the CH365P are respectively connected with the corresponding IO pins of the FPGA logic device through 4 8-bit level shifters, so that the angle signal is transmitted to the upper computer in real time at high speed through the PCI interface.

As shown in FIG. 2, this embodiment includes angle measurement circuit board, triaxial revolving stage (interior axle angle feedback device be the grating, axis angle feedback device is the grating, outer axle angle feedback device is the encoder), take the host computer (industrial computer) in PCI groove.

And the angle measuring circuit board is inserted into a PCI slot of an upper computer, and the signals of the encoders of the inner shaft, the grating of the middle shaft and the outer shaft of the three-shaft turntable are connected to the angle measuring circuit board to electrify the system. After the power is on, an FPGA logic device in the angle measuring circuit board gives out a clock signal to the rotary table outer shaft encoder, the outer shaft encoder then gives out angle data, the angle data are input to the FPGA logic device through the RS485 converter, and meanwhile grating ABZ differential signals of the rotary table inner shaft and the rotary table middle shaft are converted into single-ended ABZ signals through the differential signal converter and input to the FPGA logic device. The FPGA logic device respectively decodes the angle of the inner shaft, the middle shaft and the outer shaft after receiving the grating signals of the inner shaft and the middle shaft and the encoder signals of the outer shaft, the conversion of the FPGA 3.3V level and the PCI interface chip 5V level is completed through 4 level converters with 8 bits after the decoding is completed, then the PCI transmission protocol is realized through the PCI interface chip, and the angle transmission with an upper computer is completed through a PCI golden finger of an angle measuring circuit and a PCI slot of the upper computer, so that the high-speed and high-precision angle measuring function is realized.

Claims

1. A multi-axis rotary table composite angle measuring circuit comprises an angle measuring circuit board, a three-axis rotary table and an upper computer with a PCI slot, wherein the three-axis rotary table comprises an inner axis angle feedback device which is a grating, a middle axis angle feedback device which is a grating and an outer axis angle feedback device which is an encoder, and the angle measuring circuit board comprises an FPGA (field programmable gate array) logic device, a PCI interface chip, a PCI golden finger and an LDO (low dropout regulator) power supply chip, the angle measuring circuit board is inserted into the PCI slot of the upper computer, the inner axis of the three-axis rotary table, the grating of the middle axis and the encoder of the outer axis are connected to the angle measuring circuit board through signals, the angle measuring circuit board comprises an FPGA logic device, the FPGA logic device is connected with the encoder of the outer axis of the three-axis rotary table through 6 RS485 signal converters, the encoder of the outer axis then gives angle data, and grating ABZ differential signals of the inner axis and, the FPGA logic device respectively decodes the angle of the inner shaft, the middle shaft and the outer shaft after receiving the grating signals of the inner shaft and the middle shaft and the encoder signals of the outer shaft, the conversion of the FPGA 3.3V level and the PCI interface chip 5V level is completed through 4 level converters with 8 bits after the decoding is completed, then the PCI transmission protocol is realized through the PCI interface chip, and the angle transmission with an upper computer is completed through a PCI golden finger of an angle measuring circuit and a PCI slot of the upper computer, so that the high-speed and high-precision angle measurement is realized.

2. The compound angle measuring circuit of claim 1, wherein the 3 differential signal converters are differential signal converters of the same type, the differential signal converter is AM26LS32AIDR, the 6 RS485 signal converters are RS485 signal converters of the same type, the RS485 signal converter is MAX3485ESA +, the FPGA logic device is EP2C8T144I8N, the PCI interface chip is CH365P, the 48 level converters are 8 level converters of the same type, and the 2 LDO power chips are LDO power chips of the same type.