A vehicle-mounted seismic data acquisition system and its signal acquisition method

Abstract

This invention discloses a vehicle-mounted seismic data acquisition system and its usage method. The system includes a seismic source vehicle and at least one set of sensor delivery devices towed by the seismic source vehicle. Each sensor delivery device includes a rotating arm and a sensor connected to a first end of the rotating arm. The rotating arm rotates in a vertical plane with a second end away from the sensor as its center. The second end of the rotating arm is also connected to a drive structure. The seismic source vehicle is equipped with a seismic source device and a seismic signal acquisition instrument. All sensors, the seismic source device, and the seismic signal acquisition instrument are electrically connected to each other. This invention aims to enable the seismic source vehicle to operate continuously without stopping during the acquisition system's operation.

Description

Technical Field

[0001] This invention relates to the field of seismic exploration technology, and in particular to a vehicle-mounted seismic data acquisition system and its signal acquisition method. Background Technology

[0002] Seismic exploration is a geophysical exploration method that utilizes the differences in elasticity and density of underground media to infer the properties and morphology of underground rock strata by observing and analyzing the Earth's response to artificially induced seismic waves. Currently, seismic exploration technology can be used to investigate public squares, roadbeds, and airport runways to detect potential hazards. An existing invention patent (CN105676271A) proposes a detection vehicle and its detection method for detecting roadbed hazards. However, this method requires an intermittent "go-stop-go" operation mode. During the "stop" action, the sensor is kept in a stable coupled state with the ground, and the vehicle continues to move forward only after the seismograph has completed one data acquisition. This "stop" action interrupts the continuity of seismic exploration operations to some extent, making continuous operation inconvenient and inefficient. Therefore, there is an urgent need to develop a sustainable data acquisition system. Summary of the Invention

[0003] The main objective of this invention is to provide a vehicle-mounted seismic data acquisition system and its signal acquisition method, aiming to solve the technical problem that existing seismic data acquisition systems cannot achieve continuous operation.

[0004] To achieve the above objectives, the present invention provides a vehicle-mounted seismic data acquisition system, the system comprising: a seismic source vehicle and at least one set of sensor delivery devices towed by the seismic source vehicle;

[0005] Each sensor delivery device includes a rotating arm and a sensor connected to a first end of the rotating arm. The rotating arm rotates in a vertical plane with a second end away from the sensor as its center.

[0006] The second end of the rotating arm is also connected to a drive structure. The seismic source vehicle is equipped with a seismic source device and a seismic signal acquisition instrument. The sensors, the seismic source device and the seismic signal acquisition instrument are electrically connected to each other.

[0007] Optionally, the sensor is connected to the first end of the rotating arm via a suspension rope.

[0008] Optionally, the hoisting rope is also connected to the first end of the rotating arm via a support beam.

[0009] Optionally, a support base is connected to the bottom of the sensor.

[0010] Optionally, a first damping structure is provided around the running path of each sensor.

[0011] Optionally, each set of sensor delivery devices is mounted on the traction arm of the seismic source vehicle or on the carrier vehicle, and the seismic source vehicle pulls the carrier vehicle.

[0012] Optionally, the rotating arm is a telescopic structure.

[0013] Optionally, the second end of the rotating arm is disposed on an auxiliary wheel, and the surface of the auxiliary wheel is covered with a second damping structure.

[0014] Optionally, the drive structure includes a drive shaft that passes through the center of the auxiliary wheel and is connected to the second end of the rotating arm.

[0015] Furthermore, to achieve the above objectives, the present invention also provides a signal acquisition method for a vehicle-mounted seismic data acquisition system, the method comprising the following steps:

[0016] A sensor delivery device is installed, and the sensor delivery device is also connected to the drive structure;

[0017] The seismic source vehicle is started and controlled to run within a preset speed. The seismic source vehicle pulls the sensor delivery device. The seismic source vehicle is equipped with a seismic source device and a seismic signal acquisition instrument. The sensor delivery device includes a rotating arm and sensors. Each sensor, the seismic source device and the seismic signal acquisition instrument are electrically connected to each other.

[0018] The control drive structure drives the sensor delivery device to operate, so that the seismic source device can excite vibration and transmit trigger signals to the seismic signal acquisition instrument for a preset duration based on the start information emitted by the sensor after it touches the ground, and each sensor can collect vibration signals at its touch position after the seismic source device vibrates and transmit them to the seismic signal acquisition instrument.

[0019] This invention provides a vehicle-mounted seismic data acquisition system and its usage method, comprising a seismic source vehicle and at least one set of sensor delivery devices towed by the seismic source vehicle. Each sensor delivery device includes a rotating arm and a sensor connected to a first end of the rotating arm. The rotating arm rotates in a vertical plane with a second end away from the sensor as its center. The second end of the rotating arm is also connected to a drive structure. The seismic source vehicle is equipped with a seismic source device and a seismic signal acquisition instrument. All sensors, the seismic source device, and the seismic signal acquisition instrument are electrically connected to each other. Furthermore, by adjusting the rotational speed of the drive structure, the operating speed of the seismic source vehicle, and the connection settings between the rotating arm and the sensor, the seismic source vehicle can operate continuously on the target roadbed without stopping, effectively improving data acquisition efficiency. Simultaneously, the entire system has a simple structure, is easy to adjust and maintain, effectively reduces cost, and is easy to promote and use. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of a first embodiment of a vehicle-mounted seismic data acquisition system according to the present invention;

[0021] Figure 2 This is a schematic diagram of the structure of a second embodiment of a vehicle-mounted seismic data acquisition system according to the present invention;

[0022] Figure 3 for Figure 1 or Figure 2 The sensor delivery device and its operational status are shown in the front view.

[0023] Figure 4 for Figure 1 or Figure 2 The sensor delivery device and its operational status are shown in a side view.

[0024] Figure 5 for Figure 4 The diagram shows the rotating arm operating in a vertically upward position.

[0025] Figure 6 for Figure 4 The diagram shows the rotating arm operating vertically downwards.

[0026] Figure 7 for Figure 3 A schematic diagram of the parameters of the corresponding sensor delivery device and its operating status;

[0027] Figure 8 for Figure 3 The corresponding schematic diagram shows whether the sensor is placed on the ground or off the ground when the rotating arm is horizontal.

[0028] The realization of the purpose, functional features and advantages of this utility model will be further explained in conjunction with the embodiments and with reference to the accompanying drawings.

[0029] Explanation of icon numbers:

[0030] label name label name 1 Earthquake source vehicle 2 Cargo carrier 3 Auxiliary wheel 4 Rotating arm 5 sensor 6 Support base 7 First damping structure 8 sling 9 Drive structure 11 Seismic source device 12 Seismic signal acquisition instrument 13 Traction arm 31 Second damping structure 41 Support beam 91 drive shaft 311 Damping fluff

[0031] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0032] It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0033] See Figure 1-8As shown, the present invention discloses a structural schematic diagram of an embodiment of a vehicle-mounted seismic data acquisition system. The system includes: a seismic source vehicle 1 and at least one set of sensor delivery devices towed by the seismic source vehicle 1; each set of sensor delivery devices includes a rotating arm 4 and a sensor 5 connected to a first end of the rotating arm 4. The rotating arm 4 rotates in a vertical plane with a second end away from the sensor 5 as the center; the second end of the rotating arm 4 is also connected to a drive structure 9. The seismic source vehicle 1 is equipped with a seismic source device 11 and a seismic signal acquisition instrument 12. Each sensor 5, the seismic source device 11, and the seismic signal acquisition instrument 12 are electrically connected to each other. Preferably, the seismic source device 11 is a mechanically electrically controlled seismic source. The signal at the moment the sensor touches the ground is responded to by a mechanical contact switch installed at the bottom of the sensor. This signal is transmitted to the seismic source device as a seismic source actuation signal via wired or wireless means.

[0034] Specifically, the seismic source vehicle 1 travels at a constant speed on the target roadbed, simultaneously driving the sensor delivery device at the same speed. When the speed of the seismic source vehicle 1 reaches the target preset speed, the drive structure 9 is activated. This drive structure 9 controls the rotating arm 4 to rotate in a vertical plane around its second end, initiating data acquisition. Simultaneously, the rotating arm 4 also drives the sensor 5 to rotate. Based on the pre-set connection length between the sensor 5 and the second end of the rotating arm 4, the sensor 5 does not rotate 360 ​​degrees under the action of the rotating arm 4, but instead touches the ground for a period of time during rotation. Figure 3 As shown, in structure A, sensor 5 begins to touch the ground; in structure B, sensor 5 and rotating arm 4 are in a vertical position; and in structure C, sensor 5 finishes touching the ground. During the transition from state A to state C, sensor 5 is in a grounded state, thus enabling stable coupling between sensor 5 and the ground. Preferably, the ground coupling time is 200ms, during which the seismic source vehicle 1 is in normal operation. Simultaneously, sensor 5 sends a ground contact time signal to the seismic source device 11. Generally, the seismic source device 11 will only excite seismic waves after sensor 5 has stabilized for time t after it begins to touch the ground. After receiving the ground contact signal, there is a certain preparation time for excitation. Preferably, the stabilization time t of sensor 5 is 20ms, which can also be regarded as the preparation time for excitation of the coordinating source device 11. After excitation, a trigger signal is sent to the seismic signal acquisition instrument 12 for data acquisition for a preset duration. Preferably, the acquisition time of the seismic signal acquisition instrument 12 is 200ms. The data acquired by the seismic signal acquisition instrument 12 is the vibration signal collected by sensor 5 at the ground contact position and transmitted to the seismic signal acquisition instrument 12. This enables the acquisition of seismic data on the roadbed without stopping the source vehicle 1, thereby determining the internal condition of the roadbed.

[0035] Furthermore, such as Figure 1 As shown, each set of sensor delivery devices is installed on the carrier vehicle 2, and the source vehicle 1 pulls the carrier vehicle 2 to run, thereby realizing that the source vehicle 1 pulls the sensor delivery device to run at a constant speed. There can be more than one carrier vehicle 2, and each carrier vehicle 2 is equipped with a corresponding sensor delivery device. Preferably, the sensor delivery devices can be connected to the source vehicle or the carrier vehicle in parallel or serial manner, thereby improving the coverage or detection accuracy of the acquisition system.

[0036] Furthermore, such as Figure 2 As shown, each set of sensor delivery devices is mounted on the traction arm 13 of the seismic source vehicle 1. The traction arm 13 is generally a rigid structure, which also satisfies the requirement that the seismic source vehicle 1 pulls the sensor delivery device to run at a uniform speed.

[0037] Furthermore, such as Figure 3 As shown, the sensor 5 can also be connected to the first end of the rotating arm 4 via a suspension rope 8. The suspension rope 8 has a certain length, and its placement can effectively adjust the sensor's ground position. During the grounding time period from state A to C, the seismic source device 11 can generate vibrations, and the seismic signal acquisition instrument 12 can collect the data reflected after the vibrations through the sensor 5, which is stationary at the grounding point.

[0038] Furthermore, the suspension rope 8 is also connected to the first end of the rotating arm 4 via a support beam 41. Specifically, the support beam 41 is configured such that the rotating arm 4 and the sensor 5 are not on the same vertical plane, resulting in a certain distance between them. In a specific embodiment, such as... Figure 4-5 As shown, one end of the support beam 41 is perpendicularly connected to the first end of the rotating arm 4, and the other end is connected to the suspension rope 8, thereby preventing the sensor 5 from colliding with the surface of the rotating arm 4.

[0039] Furthermore, the bottom of the sensor 5 is connected to the support base 6. Generally, the support base 6 is a rigid three-legged or multi-legged support structure. The sensor 5 is connected and fixed to the support base 6, which facilitates the acquisition of seismic wave signals by the sensor 5 and also avoids direct contact between the sensor 5 and the ground, thus affecting the service life of the sensor 5.

[0040] Furthermore, such as Figure 2 As shown, a first damping structure 7 is provided around the running path of each sensor 5. Specifically, the first damping structure 7 is made of materials such as soft hair, sponge, velvet, and spring, and is fixed to the side of the path through which the sensor 5 passes. That is, during the movement of the sensor 5, such as when it touches the ground, sits down, or is lifted, there is a first damping structure 7 around it. The purpose of setting the first damping structure 7 is to reduce the impact of the sensor 5 on its surroundings during rotation.

[0041] Furthermore, such as Figure 5-6 As shown, the rotating arm 4 is a telescopic structure. Thus, during the rotation of the sensor 5, when the arm is bent downward, it can extend downward a certain distance without colliding with the sensor body; when the arm is bent upward, it can retract a certain distance to reduce the height of the sensor 5 in the entire circular motion and reduce swaying.

[0042] Furthermore, the second end of the rotating arm 4 can also be mounted on the auxiliary wheel 3, and the surface of the auxiliary wheel 3 is covered with a second damping structure 31, specifically, as shown in... Figure 3 As shown, the auxiliary wheel 3 has a disc structure and is parallel to the plane containing the rotation path of the rotating arm 4, and as... Figure 4 As shown, the second damping structure 31 is composed of a certain number of damping fibers 311 arranged together. Generally, the damping fibers 311 are made of flexible material, which helps the wheel 3 to provide a certain protective buffer for the sensor 5 driven by the rotating arm 4, thereby preventing the sensor from swinging or falling over, and keeping it in a vertically downward direction.

[0043] Furthermore, the drive structure 9 includes a drive shaft 91 that passes through the center of the auxiliary wheel 3 and is connected to the second end of the rotating arm 4. Preferably, the drive structure 9 is one of a motor speed regulator, a servo motor, and a stepper motor.

[0044] Furthermore, based on the vehicle-mounted seismic data acquisition system disclosed above, its signal acquisition method is described in detail below, the method comprising the following steps:

[0045] First, a sensor delivery device is installed, which is also connected to a drive structure. Specifically, the sensor delivery device includes a rotating arm and a sensor. One end of the rotating arm is connected to the drive structure, and the sensor is placed at the other end of the rotating arm away from the drive structure. At the same time, the sensor delivery device is placed on the traction arm of the seismic source vehicle or on the carrier vehicle. The seismic source vehicle pulls the carrier vehicle, and the seismic source device and seismic signal acquisition instrument installed on the seismic source vehicle are installed. It is ensured that each sensor, the seismic source device, and the seismic signal acquisition instrument are electrically connected to each other.

[0046] Furthermore, such as Figure 7 As shown, the vertical height H of the rotation center of the rotating arm should be greater than the sum of the radius R of the rotating arm and the height h of the sensor after it touches the ground, i.e., H > (R + h).

[0047] Second, start the seismic source vehicle and control it to run within the preset speed;

[0048] Specifically, the operating speed v of the seismic source vehicle is related to the radius R of the rotating arm, the vertical height H of the rotating arm's rotation center, the length L of the suspension rope, and the height h of the sensor after it touches the ground. The specific formula for calculating the speed is as follows:

[0049] Where dT is the set time required for a single data acquisition by the seismic signal acquisition instrument, and t is the initial ground stabilization time of the sensor.

[0050] Third, the control drive structure drives the sensor deployment device to operate, so that the seismic source device excites vibration and transmits trigger signals to the seismic signal acquisition instrument for a preset duration based on the start-up information emitted by the sensor after it touches the ground, and each sensor collects vibration signals at its respective touch-down position after the seismic source device vibrates and transmits them to the seismic signal acquisition instrument. Specifically, as shown in the example... Figure 7 As shown, the drive structure drives the rotating arm to rotate in a vertical plane around the second end of the rotating arm, which is away from the sensor, and the angular velocity of the drive structure is... The angular velocity of the motor is approximately in The central angle of the rotating arm's movement corresponds to the sensor's ground-to-ground state during the rotation of the rotating arm. It can be seen that a larger effective length R of the deployment device's rotating arm, a slower forward speed V of the seismic source vehicle, or a slower angular velocity ω of the deployment device's motor can all ensure a longer sensor ground-contact time. Simultaneously, while ensuring the duration of a single seismic data acquisition, increasing the speed of the seismic source vehicle increases the sensor deployment interval between two adjacent seismic data acquisitions, reducing the spatial sampling rate of seismic exploration; conversely, slowing down the speed of the seismic source vehicle correspondingly reduces the deployment interval, increasing the spatial sampling rate of seismic exploration.

[0051] Furthermore, when the rotating arm is horizontal, the sensor is either on the ground or off the ground, and in this case, the central angle... It is 180 degrees, specifically as follows: Figure 8 As shown, the distance the seismic source vehicle travels is 2*R, and its speed is 2*R / (dT+t), which in turn drives the structure to rotate clockwise at an angular velocity of π / (dT+t). Generally, the radius R of the rotating arm is set to 10–50 cm, and the minimum data acquisition time for a single seismograph session is 75 ms, with a maximum of 200 ms. The minimum time required for the sensor to stabilize is 25 ms, with a maximum of 100 ms. The forward speed V of the seismic source vehicle is 2.4 km / h–36 km / h, corresponding to the angular velocity of the drive motor. The corresponding range is: 10π / 3s~10π / s.

[0052] Furthermore, in a specific embodiment, if the radius R of the rotating arm is set to 0.5m, then the maximum operating speed of the seismic source vehicle is v = 1m / 100ms = 10m / s = 36km / h.

[0053] Furthermore, in a specific embodiment, the vertical height H of the rotation center of the rotating arm can be set to 25cm, the sensor height h to 10cm, and the radius R of the rotating arm to 14.5cm, satisfying the requirement that H>(R+h). The seismograph is designed to acquire data for 200ms per session, and the sensor reaches stability 20ms after initial ground contact. Then, according to the formula: ω=2arccos{[H-(h+L)] / R} / (dT+t), the angular velocity ω of the adjustable speed motor used for the deployment device is set to be approximately 14.28 radians / s.

[0054] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or system. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or system that includes that element.

[0055] The sequence numbers of the above embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0056] The above are merely preferred embodiments of the present invention and do not limit the scope of the patent. Any equivalent structural or procedural transformations made based on the description and drawings of the present invention, or direct or indirect applications in other related technical fields, are similarly included within the scope of patent protection of the present invention.

Claims

1. A vehicle-mounted seismic data acquisition system, characterized in that, The system includes: a seismic source vehicle (1) and at least one sensor delivery device towed by the seismic source vehicle (1); Each sensor delivery device includes a rotating arm (4) and a sensor (5) connected to the first end of the rotating arm (4). The rotating arm (4) rotates in a vertical plane with the second end away from the sensor (5) as the center. The sensor (5) is connected to the first end of the rotating arm (4) by a suspension rope (8). The second end of the rotating arm (4) is also connected to the drive structure (9), which controls the rotation of the rotating arm (4) so ​​that the sensor (5) remains vertically stationary when it touches the ground, and the drive structure (9) controls the duration of the sensor (5) touching the ground. The seismic source vehicle (1) is equipped with a seismic source device (11) and a seismic signal acquisition instrument (12), and each sensor (5), the seismic source device (11) and the seismic signal acquisition instrument (12) are electrically connected to each other; The sensor (5) is configured to send a start signal to the seismic source device (11) after landing. The seismic source device (11) responds to the start signal to generate vibration and transmits a trigger signal to the seismic signal acquisition instrument (12) for data acquisition. A first damping structure (7) is provided around the running path of each sensor (5).

2. The vehicle-mounted seismic data acquisition system according to claim 1, characterized in that, The hoisting rope (8) is also connected to the first end of the rotating arm (4) via a support beam (41).

3. The vehicle-mounted seismic data acquisition system according to claim 1, characterized in that, The sensor (5) is connected to a support base (6) at its bottom.

4. The vehicle-mounted seismic data acquisition system according to any one of claims 1 to 3, characterized in that, Each set of sensor delivery devices is installed on the traction arm (13) of the source vehicle (1) or on the carrier vehicle (2), and the source vehicle (1) pulls the carrier vehicle (2) to run.

5. The vehicle-mounted seismic data acquisition system according to claim 4, characterized in that, The rotating arm (4) is a telescopic structure.

6. The vehicle-mounted seismic data acquisition system according to claim 4, characterized in that, The second end of the rotating arm (4) is mounted on the auxiliary wheel (3), and the surface of the auxiliary wheel (3) is covered with a second damping structure (31).

7. The vehicle-mounted seismic data acquisition system according to claim 6, characterized in that, The drive structure (9) includes a drive shaft (91) that passes through the center of the auxiliary wheel (3) and is connected to the second end of the rotating arm (4).

8. A signal acquisition method for a vehicle-mounted seismic data acquisition system as described in any one of claims 1 to 7, characterized in that, The method includes the following steps: A sensor delivery device is installed, and the sensor delivery device is also connected to the drive structure; The seismic source vehicle is started and controlled to run within a preset speed. The seismic source vehicle pulls the sensor delivery device. The seismic source vehicle is equipped with a seismic source device and a seismic signal acquisition instrument. The sensor delivery device includes a rotating arm and sensors. Each sensor, the seismic source device and the seismic signal acquisition instrument are electrically connected to each other. The control drive structure drives the sensor delivery device to operate, so that the rotating arm drives the sensor to rotate in the vertical plane and remains vertically stationary when the sensor touches the ground; After the sensor touches the ground, it sends a start-up message to the seismic source device. The seismic source device responds to the start-up message by generating vibrations and transmits a trigger signal to the seismic signal acquisition instrument for data acquisition for a preset duration. Each sensor collects vibration signals at its landing position after the seismic source device vibrates and transmits them to the seismic signal acquisition instrument.

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