CN219715755U - Laser ranging data acquisition device - Google Patents

Abstract

The utility model provides a laser ranging data collection device, which can be applied in the technical field of laser ranging. The device includes: signal acquisition and processing module and human-computer interaction module. Among them, the signal acquisition and processing module includes amplifiers, high-speed comparators, FPGA SOC chips, ADC chips, SD cards, crystal oscillator chips, level conversion interfaces and Ethernet data transmission interfaces. The FPGA SOC chip includes a programmable logic unit and a processing unit. The programmable logic unit includes a time window module, a time interval measurement module, a multi-pulse accumulation algorithm processing module, a data processing module, and a data transmission module. The laser ranging data acquisition device provided by the utility model can conduct real-time dynamic ranging of detection targets in two different modes, and transmit back the distance value in real time. It has the advantages of simple circuit, low cost, high real-time performance, long-distance detection, The advantage of low noise interference effectively improves the accuracy of ranging and the reliability of target monitoring.

Description

Laser ranging data acquisition device

Technical field

The utility model relates to the technical field of ranging, and in particular to a laser ranging data collection device.

Background technique

Laser ranging technology usually uses the laser pulse signal emitted by the system to irradiate the target object, and the laser echo signal is obtained by reflection on the target object. The laser echo signal is then received by the system. By calculating the flight time of the laser in the atmosphere, to calculate the measured distance. In recent years, with the rapid development of information technology, the application scope of laser ranging has become wider and wider, and it can be used in fields such as electric power, water conservancy, military, construction, and lidar.

Laser ranging devices generally consist of an optical-mechanical unit, a photoelectric receiving unit, a time interval measurement system, a data control and an acquisition and processing system. Existing laser ranging data acquisition devices basically use hardware circuits to filter out noise in real time, and the circuits are very It is complex, and the pointing of the ranging target is simple. It cannot intelligently judge the expected target or actively filter out unintended targets. It is prone to problems such as ranging errors when the signal-to-noise ratio is poor. The time interval measurement in the laser ranging data acquisition device includes analog method and digital insertion method. The analog method mostly uses ADC chip (ADC mode) to obtain the required information by measuring the voltage value converted into the analog signal after charging and discharging. The measurement accuracy is high. However, there are limitations on the measurement range. The digital insertion method mostly uses TDC chips (TDC mode) to time the time intervals through synchronous clock pulses. Although the digital insertion method does not have a measurement range limit, it may be affected by weak signals. Accurate results cannot be obtained due to the influence of noise. Therefore, it is necessary to provide a laser ranging data acquisition device that can combine ADC mode and TDC mode to achieve accurate distance measurement regardless of signal strength.

Utility model content

In view of the above problems, the present utility model provides a laser ranging data acquisition device to solve the problem of complicated circuits in the existing technology, simple ranging target pointing, inability to intelligently judge expected targets or actively filter out unintended targets, and signal noise. When it is relatively poor, it is easy to cause measurement errors.

The utility model provides a laser ranging data collection device, which includes:

Signal acquisition and processing module and human-computer interaction module, the signal acquisition and processing module is connected with the human-computer interaction module;

The signal acquisition and processing module includes amplifiers, high-speed comparators, FPGA SOC chips, ADC chips, SD cards, crystal oscillator chips, level conversion interfaces and Ethernet data transmission interfaces.

According to the embodiment of the present utility model, the amplifier is connected to the high-speed comparator and the ADC chip respectively, the ADC chip is connected to the level conversion interface, the amplifier is connected to the high-speed comparator, and the high-speed comparator, SD card, crystal oscillator chip, and level conversion interface are all connected. Connected to the FPGA SOC chip, the FPGA SOC chip is connected to the human-computer interaction module through the Ethernet data transmission interface, and the signal acquisition and processing module is set on the PCB substrate.

According to the embodiment of the present invention, the FPGA SOC chip includes a programmable logic unit and a processing unit. The programmable logic unit includes a time window module, a time interval measurement module, a multi-pulse accumulation algorithm processing module, a data processing module, and a data transmission module;

The time interval measurement module, data processing module and data transmission module are connected in sequence, and the time window module is connected to the time interval measurement module, multi-pulse accumulation algorithm processing module and data processing module respectively.

According to an embodiment of the present invention, the processing unit includes an SD card startup module and an Ethernet control module. The SD card startup module is connected to the SD card, and the Ethernet control module is connected to the Ethernet data transmission interface.

According to the embodiment of the present invention, the time interval measurement module includes a counter and a carry delay chain, and the counter and the carry delay chain are respectively connected to the data processing module.

According to the embodiment of the present invention, the PCB substrate includes 1 power layer, 2 ground layers and 3 signal layers. The signal lines on the PCB substrate are designed at equal intervals, and the wiring on the PCB substrate is a serpentine wiring.

According to an embodiment of the present invention, the PCB substrate further includes N impedance matching resistors, where N is an integer greater than 1.

According to an embodiment of the present invention, the laser ranging data collection device further includes a smart camera, and the smart camera is connected to the human-computer interaction module.

The laser ranging data collection device provided by the utility model can perform real-time dynamic ranging on the detection target in two modes, ADC and TDC, and transmit back the target image in real time. It has the advantages of simple circuit, low cost, high real-time performance and long distance. It has the advantages of small detection and noise interference, which effectively improves the reliability of target monitoring and the accuracy of ranging when the laser echo signal is weak.

Description of drawings

The above and other objects, features and advantages of the present invention will be more clearly described through the following description of the embodiments of the present invention with reference to the accompanying drawings, in which:

Figure 1 schematically shows a structural diagram of a laser ranging data acquisition device according to an embodiment of the present invention;

Figure 2 schematically shows a schematic structural diagram of an FPGA SOC chip according to an embodiment of the present invention;

Figure 3 schematically shows a schematic diagram of the time interval measurement principle according to an embodiment of the present invention;

Figure 4 schematically shows a circuit diagram of an amplifier according to an embodiment of the present invention;

Figure 5 schematically shows a circuit diagram of a high-speed comparator according to an embodiment of the present invention;

Figure 6 schematically shows a circuit pin diagram of an FPGA SOC chip according to an embodiment of the present invention;

Figure 7 schematically shows a schematic diagram of the circuit connection between the FPGA SOC chip and the SD card according to an embodiment of the present invention; and

Figure 8 schematically shows a circuit connection diagram between an FPGA SOC chip and an Ethernet data transmission interface according to an embodiment of the present invention.

Detailed ways

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are only exemplary and are not intended to limit the scope of the present invention. In the following detailed description, for convenience of explanation, numerous specific details are set forth to provide a comprehensive understanding of the embodiments of the invention. It will be apparent, however, that one or more embodiments may be practiced without these specific details. Furthermore, in the following description, descriptions of well-known structures and techniques are omitted to avoid unnecessarily confusing the concepts of the present invention.

The terminology used herein is for describing specific embodiments only and is not intended to limit the invention. The terms "comprising," "comprising," and the like, as used herein, indicate the presence of stated features, steps, operations, and/or components but do not exclude the presence or addition of one or more other features, steps, operations, or components.

All terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art, unless otherwise defined. It should be noted that the terms used here should be interpreted to have meanings consistent with the context of this specification and should not be interpreted in an idealized or overly rigid manner.

Where an expression similar to "at least one of A, B, C, etc." is used, it should generally be interpreted in accordance with the meaning that a person skilled in the art generally understands the expression to mean (e.g., "having A, B and C "A system with at least one of" shall include, but is not limited to, systems with A alone, B alone, C alone, A and B, A and C, B and C, and/or systems with A, B, C, etc. ).

Figure 1 schematically shows a structural diagram of a laser ranging data collection device according to an embodiment of the present invention. As shown in Figure 1, in this embodiment, the laser ranging data collection device provided by the present utility model includes: a signal collection and processing module and a human-computer interaction module. The signal collection and processing module is connected to the human-computer interaction module. Among them, the signal acquisition and processing module includes: amplifier, high-speed comparator, FPGA SOC chip, ADC chip, SD card, crystal oscillator chip, level conversion interface and Ethernet data transmission interface.

As shown in Figure 1, in this embodiment, the ADC chip is connected to the level conversion interface, the amplifier is connected to the high-speed comparator and the ADC chip respectively, and the high-speed comparator, SD card, crystal oscillator chip, and level conversion interface are all connected to the FPGA SOC For chip connection, the FPGA SOC chip is connected to the human-computer interaction module through the Ethernet data transmission interface, and the signal acquisition and processing module is entirely installed on the PCB substrate.

Specifically, the SD card provides system files for the FPGA SOC chip, and the crystal oscillator chip provides a clock signal for the FPGA SOC chip. The frequency range of the clock signal is 33.33MHz to 100MHz. The laser pulse signal emitted by the laser ranging device is reflected by the target object to obtain the laser echo signal. The photoelectric detector converts the laser echo signal into an analog echo electrical signal. The synchronization signal emitted by the laser ranging device is used as the reference signal. The signal and the simulated echo electrical signal are input into the laser ranging data acquisition device provided by the utility model, and the reference signal and the simulated echo electrical signal are respectively amplified through the amplifier. The amplified reference signal and the simulated echo electrical signal enter high-speed comparison. The reference signal and the analog echo electrical signal are converted into a digital reference signal and a digital echo electrical signal respectively through a high-speed comparator or ADC chip. When the level conversion interface receives the digital reference signal and digital echo signal sent by the ADC chip, After echoing the electrical signal, the digital reference signal and the digital echo electrical signal are level-converted to obtain a fixed-level digital reference signal and a digital echo electrical signal. The FPGA SOC chip performs level conversion on the fixed-level digital reference signal and digital echo signal. The echo electrical signal is processed to measure the distance value between the ranging device and the target object, and the distance value is transmitted to the human-human interaction module for display through the Ethernet data transmission interface. The digital echo electrical signal includes a first digital echo electrical signal and a second digital echo electrical signal.

The utility model forms a fully digital processing circuit based on FPGA, has high real-time performance, can perform real-time dynamic ranging of detection targets, and has the advantages of simple circuit and low cost.

Figure 2 schematically shows a schematic structural diagram of an FPGA SOC chip according to an embodiment of the present invention. As shown in Figure 2, in this embodiment, the FPGA SOC chip includes a programmable logic unit and a processing unit. The programmable logic unit includes a time window module, a time interval measurement module, a multi-pulse accumulation algorithm processing module, a data processing module and a data processing module. Transmission module. The time interval measurement module, data processing module and data transmission module are connected in sequence, and the time window module is connected to the time interval measurement module, multi-pulse accumulation algorithm processing module and data processing module respectively.

As shown in Figure 2, in this embodiment, the processing unit includes an SD card startup module and an Ethernet control module. The SD card startup module is connected to the SD card, and the Ethernet control module is connected to the Ethernet data transmission interface.

When the programmable logic unit receives the digital reference signal and the digital echo electrical signal, the time interval measurement module measures the time interval between the received digital echo electrical signal and the digital reference signal. The time window module receives the upper level of the human-computer interaction module. According to the instructions of the machine, preliminary noise filtering is performed on this time interval to reduce interfering noise points. The time interval is then transmitted to the data processing module, which converts the time interval into a distance value, and transmits the distance value to the processing unit through the data transmission module. The processing unit then transmits the distance value through the Ethernet data transmission interface. Send it to the human-human interaction module for display.

It should be noted that the time interval measurement module can also be replaced by an independent ASIC and/or a dedicated chip, which is not limited by the present invention.

Since the correlation of laser echo signals is extremely strong, but there is no correlation in noise signals, the utility model uses the multi-pulse accumulation algorithm processing module to convert multiple weak laser echo signals into digital echo electrical signals according to the correlation Correlation superposition can improve the signal-to-noise ratio of the superimposed signals, thereby obtaining accurate distance value measurement results. And the time window module receives the instructions given by the human-computer interaction module, and removes all the data outside the time window module to filter out the noise, which greatly increases the accuracy of the ranging results.

Figure 3 schematically shows a schematic diagram of the time interval measurement principle according to an embodiment of the present invention. As shown in Figure 3, in this embodiment, the time interval measurement module includes a counter and a carry delay chain, and the counter and the carry delay chain are respectively connected to the data processing module.

The counter starts, the reference signal converted from the laser pulse signal enters the FPGA SOC chip, the carry delay chain starts to work, and the t1 value is obtained; the laser pulse signal encounters the target and is reflected back to the laser echo signal, and the laser echo signal is converted into a digital The echo electrical signal enters the FPGA SOC chip, and the carry chain delay chain works again to obtain the t2 value; the period of the clock CLK is T, therefore, the time difference is Δt=Tclk+t1-t2, and the distance difference is d=△ t*3*108/2. Therefore, the distance value between the laser ranging data collection device and the detection target can be calculated by using the time difference between the laser pulse signal and the laser echo signal reaching the laser ranging data collection device.

In some embodiments, the PCB substrate includes 1 power layer, 2 ground layers and 3 signal layers, the signal lines on the PCB substrate are designed at equal intervals, and the traces on the PCB substrate are serpentine traces.

In some embodiments, the PCB substrate further includes N impedance matching resistors, where N is an integer greater than 1.

As shown in Figure 2, in this embodiment, the laser ranging data collection device also includes a smart camera, and the smart camera is connected to the human-computer interaction module.

Figure 4 schematically shows a circuit schematic diagram of an amplifier according to an embodiment of the present invention. Figure 5 schematically shows a circuit schematic diagram of a high-speed comparator according to an embodiment of the present invention. Figure 6 schematically shows a circuit schematic diagram of an amplifier according to an embodiment of the present invention. A schematic diagram of the circuit pins of the FPGA SOC chip according to the new embodiment. Figure 7 schematically shows a schematic diagram of the circuit connection between the FPGA SOC chip and the SD card according to the embodiment of the present utility model. Figure 8 schematically shows the circuit pin diagram of the FPGA SOC chip according to the embodiment of the present utility model. Schematic diagram of the circuit connection between the FPGASOC chip and the Ethernet data transmission interface.

As shown in Figure 4-8, the FPGA SOC chip uses Xilinx's Zynq series XC7Z020CLG400-2I, the ADC chip model is LS08D2000, the amplifier chip model is OPA855, the high-speed comparator chip model is TLV3501, and the Ethernet data transmission interface chip model for the RTL8211E.

The utility model reduces the reflection of the laser echo signal by increasing the impedance matching resistor to improve the signal quality of the digital echo electrical signal. While measuring distance in real time, the smart camera is used to capture the target image in real time and transmit it to the host computer of the human-human interaction module for display. It has high real-time performance and effectively improves the reliability of target monitoring.

Specifically, with reference to Figures 1-8, the specific distance measurement process of the laser ranging data acquisition device provided by the utility model is as follows: the laser pulse signal emitted by the laser ranging device is reflected by the target object to obtain a laser echo signal, and the photoelectric detector will The laser echo signal is converted into an analog echo electrical signal. The synchronization signal emitted by the laser ranging device is used as a reference signal. The reference signal and the analog echo electrical signal are input into the laser ranging data acquisition device provided by the utility model. The reference signal The analog echo electrical signal and the analog echo electrical signal are amplified by the amplifier and then transmitted to a high-speed comparator or ADC chip. The reference signal and analog echo electrical signal are converted into a digital reference signal and a digital echo electrical signal respectively through the high-speed comparator or ADC chip ( The high-speed comparator converts the analog echo electrical signal into the first digital echo electrical signal, which is applied in the TDC mode; the ADC chip converts the analog echo electrical signal into the second digital echo electrical signal, which is applied in the ADC mode). After the level conversion interface receives the digital reference signal and digital echo electrical signal sent by the ADC chip, it performs level conversion on the digital reference signal and digital echo electrical signal to obtain a fixed-level digital reference signal and digital echo electrical signal. Transmitted to the programmable logic unit in the FPGA SOC chip.

If the digital echo electrical signal is the first digital echo electrical signal, the time interval and time window between the first digital echo electrical signal and the digital reference signal are obtained through the carry delay chain and counter in the time interval measurement module. The module receives instructions from the host computer in the human-computer interaction module and performs noise filtering on the time interval to reduce interference noise points. The time interval is then transmitted to the data processing module, which converts the time interval into a distance value, and transmits the distance value to the processing unit through the data transmission module. The processing unit then transmits the distance value through the Ethernet data transmission interface. Send it to the human-human interaction module for display. At the same time, the smart camera photographs the detection target every preset time, and transmits the captured target image to the human-human interaction module for display. The preset time can be any time period, and the utility model does not limit this.

If it is found that the measured distance value is large, or there is a lot of ranging noise and interference, and the signal-to-noise ratio of the echo signal is low, it means that the laser echo signal is weak at this time, so the ADC mode is used, that is, the second digital The echo electrical signal, after obtaining the fixed-level digital reference signal and the second digital echo electrical signal through the level conversion interface, first passes through the multi-pulse accumulation algorithm processing module to the fixed-level digital reference signal and the second digital echo signal. The electrical signals are correlated and superimposed respectively, and then the superimposed digital reference signal and the second digital echo electrical signal are transmitted to the data processing module, and the digital reference signal and the second digital echo electrical signal are obtained through the data processing module. The time interval of the signal, then the time window module receives the instructions from the host computer in the human-computer interaction module, and performs noise filtering on the time interval to reduce interference noise points. The time interval is converted into a distance value through the data processing module. Then refer to the first digital echo electrical signal for distance value transmission and real-time target image shooting. It should be noted that the host computer of the human-computer interaction module is equipped with a program for selecting the TDC mode and the ADC mode. The TDC mode and the ADC mode can be selected through The program automatically selects or manually selects. When automatically selected, it can be compared with a preset threshold for judgment. The threshold can be distance or signal-to-noise ratio, and there is no limit here.

In summary, this utility model forms a fully digital processing circuit based on FPGA, which can perform real-time dynamic ranging of detection targets in two modes: ADC and TDC, and transmit back target images in real time. It does not rely on hardware circuits for noise filtering and reduces Noise interference avoids the problem of ranging errors when the signal-to-noise ratio is poor, greatly improves the accuracy of ranging and the reliability of target monitoring, and realizes real-time dynamic monitoring of detection targets.

The laser ranging data acquisition device provided by the utility model has the advantages of simple circuit, low cost, high real-time performance, long-distance detection, and small noise interference, which effectively improves the reliability of target monitoring and improves the reliability of target monitoring when the laser echo signal is weak. ranging accuracy.

Those skilled in the art will understand that the features described in the various embodiments and/or claims of the present invention can be combined and/or combined in various ways, even if such combinations or combinations are not explicitly described in the present invention. In particular, the features described in the various embodiments and/or claims of the present invention may be combined and/or combined in various ways without departing from the spirit and teachings of the present invention. All these combinations and/or combinations fall within the scope of the present invention.

The embodiments of the present invention have been described above. However, these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. Although each embodiment is described separately above, this does not mean that the measures in the various embodiments cannot be used in combination to advantage. The scope of the invention is defined by the appended claims and their equivalents. Without departing from the scope of the present utility model, those skilled in the art can make various substitutions and modifications, and these substitutions and modifications should all fall within the scope of the present utility model.

Claims (8)

1. A laser ranging data acquisition device, characterized in that it includes: a signal acquisition and processing module and a human-computer interaction module, the signal acquisition and processing module is connected to the human-computer interaction module; The signal acquisition and processing module includes an amplifier, a high-speed comparator, an FPGA SOC chip, an ADC chip, an SD card, a crystal oscillator chip, a level conversion interface and an Ethernet data transmission interface. 2. The laser ranging data acquisition device according to claim 1, characterized in that the amplifier is connected to the high-speed comparator and the ADC chip respectively, and the ADC chip is connected to the level conversion interface. The high-speed comparator, SD card, crystal oscillator chip, and level conversion interface are all connected to the FPGA SOC chip. The FPGA SOC chip is connected to the human-computer interaction module through the Ethernet data transmission interface. The signal acquisition and processing The module is installed on the PCB substrate. 3. The laser ranging data collection device according to claim 1 or 2, characterized in that the FPGA SOC chip includes a programmable logic unit and a processing unit, and the programmable logic unit includes a time window module, a time interval measurement module, Multi-pulse accumulation algorithm processing module, data processing module, data transmission module; The time interval measurement module, data processing module and data transmission module are connected in sequence, and the time window module is connected to the time interval measurement module, the multi-pulse accumulation algorithm processing module and the data processing module respectively. 4. The laser ranging data acquisition device according to claim 3, characterized in that the processing unit includes an SD card startup module and an Ethernet control module, the SD card startup module is connected to the SD card, and the The Ethernet control module is connected to the Ethernet data transmission interface. 5. The laser ranging data acquisition device according to claim 3, wherein the time interval measurement module includes a counter and a carry delay chain, and the counter and the carry delay chain are respectively connected to the data processing module. . 6. The laser ranging data collection device according to claim 2, characterized in that the PCB substrate includes 1 power layer, 2 ground layers and 3 signal layers, and the signal lines on the PCB substrate are equally spaced. Design, the wiring of the PCB substrate is a serpentine wiring. 7. The laser ranging data acquisition device according to claim 6, wherein the PCB substrate further includes N impedance matching resistors, and N is an integer greater than 1. 8. The laser ranging data collection device according to claim 1, characterized in that the laser ranging data collection device further includes a smart camera, and the smart camera is connected to the human-computer interaction module.