Underground coal mine articulated unmanned vehicle transverse control system and method

Abstract

The invention provides a transverse control system and method for an underground coal mine articulated unmanned vehicle, and the system is characterized in that a steering parameter sensing device is used for obtaining the steering parameters of the vehicle, and the steering parameters comprise the actual articulated angle of the vehicle; the driving parameter sensing device is used for obtaining driving parameters of the vehicle, and the driving parameters comprise a front vehicle body course angle, a front vehicle body speed and a rear vehicle body speed; the load parameter sensing device is used for obtaining load parameters of the vehicle, and the load parameters comprise load capacity; the tracking parameter sensing device is used for obtaining the tracking parameters of the vehicle, and the tracking parameters comprise the driving track of the vehicle and the course error and the lateral error of the vehicle from the driving distance to the preview point; the vehicle decision controller is used for calculating an expected hinge angle based on a steering parameter, a driving parameter, a load parameter and a tracking parameter; the steering control device is used for adjusting the hinging angle of the vehicle based on the expected hinging angle so as to achieve vehicle transverse control.

Description

Technical Field

[0001] The present invention relates to the field of digital production and unmanned driving technology in coal mines, and in particular to a lateral control system and method for an articulated unmanned driving vehicle in a coal mine. Background Art

[0002] Coal mine intelligence is the core technical support for the high-quality development of coal mines. The underground transportation environment of coal mines is dark, the space is narrow, and the road environment is complex. In recent years, transportation accidents have occurred frequently. The application of unmanned driving technology to improve the level of intelligent transportation in coal mines is a key technology to solve transportation safety hazards.

[0003] The articulated vehicle consists of two parts, front and rear, connected by an articulated mechanism in the middle. This structure can reduce the turning radius and improve the vehicle's handling stability. It has good adaptability to the narrow driving environment of underground coal mine tunnels and is widely used for underground material transportation. The deployment and control of unmanned driving systems for articulated vehicles in coal mines is an important direction for the application of unmanned driving in coal mines. Articulated vehicles complete vehicle turns by controlling the articulation angle, and their lateral control methods and systems are insufficient, and trajectory control is relatively complex. At present, there is a lack of lateral control technology for articulated unmanned vehicles with high control accuracy. Summary of the invention

[0004] The present invention aims to solve one of the technical problems in the related art at least to a certain extent.

[0005] To this end, a first object of the present invention is to provide a lateral control system for an articulated unmanned vehicle in an underground coal mine, so as to improve the accuracy of lateral control of the articulated unmanned vehicle.

[0006] The second object of the present invention is to provide a lateral control method for an articulated unmanned vehicle in an underground coal mine.

[0007] To achieve the above-mentioned object, the first aspect of the present invention proposes a lateral control system for an articulated unmanned vehicle in a coal mine, comprising a steering parameter sensing device, a driving parameter sensing device, a load parameter sensing device, a tracking parameter sensing device, a vehicle decision controller, and a steering control device;

[0008] The steering parameter sensing device is used to obtain the steering parameters of the vehicle, and the steering parameters include the actual articulation angle of the vehicle;

[0009] The driving parameter sensing device is used to obtain the driving parameters of the vehicle, and the driving parameters include the front vehicle body heading angle, the front vehicle body speed and the rear vehicle body speed;

[0010] The load parameter sensing device is used to obtain the load parameters of the vehicle, and the load parameters include the load weight;

[0011] The tracking parameter sensing device is used to obtain the tracking parameters of the vehicle, and the tracking parameters include the vehicle's driving trajectory, and the heading error and lateral error of the vehicle from the preview point;

[0012] The vehicle decision controller is used to calculate the desired articulation angle based on the steering parameter, the driving parameter, the load parameter, and the tracking parameter;

[0013] The steering control device is used to adjust the articulation angle of the vehicle based on the desired articulation angle to achieve lateral control of the vehicle.

[0014] In the lateral control system of an articulated unmanned vehicle in an underground coal mine provided by the first aspect of the present invention, the steering parameter sensing device includes a first steering cylinder stroke sensor and a second steering cylinder stroke sensor; the first steering cylinder stroke sensor and the second steering cylinder stroke sensor are respectively installed in the corresponding steering control hydraulic cylinder, and are used to collect the cylinder stroke of the corresponding steering control hydraulic cylinder; the steering parameter sensing device calculates the actual articulation angle of the vehicle based on the cylinder stroke.

[0015] In the lateral control system of an articulated unmanned vehicle in an underground coal mine provided by the first aspect of the present invention, the first steering cylinder stroke sensor and the second steering cylinder stroke sensor are wire-drawing distance measuring sensors.

[0016] In the lateral control system of an articulated unmanned vehicle in an underground coal mine provided by the first aspect of the present invention, the driving parameter sensing device includes an inertial navigation device, a wheel speed meter and a radar device. The inertial navigation device is installed at the center of mass of the front vehicle body, and the wheel speed meter is arranged on both the front vehicle body and the rear vehicle body. The radar device is installed on the sides of the front vehicle body and the rear vehicle body. The radar device is used to detect the distance between the front vehicle body and the rear vehicle body and the coal wall of the driving lane respectively, so as to warn whether the vehicle hits the wall during lateral control. The driving parameters also include the distance between the front vehicle body and the rear vehicle body and the coal wall of the driving lane respectively.

[0017] In the lateral control system of an articulated unmanned vehicle in an underground coal mine provided by the first aspect of the present invention, the vehicle decision controller is also used to fine-tune the desired articulation angle based on the heading error and lateral error between the vehicle's current driving trajectory point position and the next preview point of the planned trajectory, as well as the distances between the front vehicle body and the rear vehicle body and the coal wall of the driving tunnel respectively.

[0018] In the lateral control system of an articulated unmanned vehicle in an underground coal mine provided by the first aspect of the present invention, the steering control device includes a first steering control hydraulic cylinder, a second steering control hydraulic cylinder, a controller, and a cylinder control valve. The controller calculates a first length of the first steering control hydraulic cylinder and a second length of the second steering control hydraulic cylinder based on the desired articulation angle, and adjusts the cylinder stroke of the corresponding steering control hydraulic cylinder through the cylinder control valve based on the first length and the second length to adjust the articulation angle of the vehicle.

[0019] In the lateral control system of an articulated unmanned vehicle in an underground coal mine provided by the first aspect of the present invention, the steering control device also includes a first steering pressure sensor, a second steering pressure sensor and a prediction model; the first steering pressure sensor and the second steering pressure sensor are used to collect the cylinder pressure of the corresponding steering control hydraulic cylinder; the input of the prediction model is the cylinder stroke and the cylinder pressure, and the output is the closing position and closing time of the cylinder control valve; when the first length and the second length are calculated, the cylinder stroke and the cylinder pressure at the corresponding time are sent to the prediction model to obtain the required closing position and closing time; when the position and time of the cylinder control valve reach the required closing position and closing time, the cylinder control valve is controlled to close.

[0020] In the lateral control system of an articulated unmanned vehicle in an underground coal mine provided by the first aspect of the present invention, the vehicle decision controller is also used to calculate the vehicle turning radius based on the expected articulation angle, and control the rotation of the wheels of the rear vehicle body based on the vehicle turning radius.

[0021] To achieve the above-mentioned purpose, the second aspect of the present invention proposes a lateral control method for an articulated unmanned vehicle in a coal mine, which is applicable to the lateral control system for an articulated unmanned vehicle in a coal mine provided in the first aspect, and the method comprises:

[0022] Obtaining the steering parameters, driving parameters, load parameters, and tracking parameters of the vehicle; the steering parameters include the actual articulation angle of the vehicle; the driving parameters include the heading angle of the front vehicle body, the front vehicle body speed, and the rear vehicle body speed; the load parameters include the load weight; the tracking parameters include the driving trajectory of the vehicle, and the heading error and lateral error of the vehicle from the preview point;

[0023] Calculate a desired articulation angle based on the steering parameter, the driving parameter, the load parameter, and the tracking parameter;

[0024] The articulation angle of the vehicle is adjusted based on the desired articulation angle to achieve lateral control of the vehicle.

[0025] In the lateral control method for an articulated unmanned vehicle in an underground coal mine provided in the second aspect of the present invention, the driving parameters also include the distances between the front vehicle body and the rear vehicle body and the coal wall of the driving tunnel respectively, and the method also includes fine-tuning the expected articulation angle based on the heading error and lateral error between the current driving trajectory point position of the vehicle and the next preview point of the planned trajectory, and the distances between the front vehicle body and the rear vehicle body and the coal wall of the driving tunnel respectively.

[0026] In the lateral control system and method for an articulated unmanned vehicle in an underground coal mine provided by the present invention, the system includes a steering parameter sensing device, a driving parameter sensing device, a load parameter sensing device, a tracking parameter sensing device, a vehicle decision controller, and a steering control device; the steering parameter sensing device is used to obtain the steering parameters of the vehicle, and the steering parameters include the actual articulation angle of the vehicle; the driving parameter sensing device is used to obtain the driving parameters of the vehicle, and the driving parameters include the heading angle of the front vehicle body, the front vehicle body speed, and the rear vehicle body speed; the load parameter sensing device is used to obtain the load parameters of the vehicle, and the load parameters include the load weight; the tracking parameter sensing device is used to obtain the tracking parameters of the vehicle, and the tracking parameters include the driving trajectory of the vehicle, and the heading error and lateral error of the vehicle from the preview point; the vehicle decision controller is used to calculate the expected articulation angle based on the steering parameter, driving parameter, load parameter, and tracking parameter; the steering control device is used to adjust the articulation angle of the vehicle based on the expected articulation angle to achieve lateral control of the vehicle. In this case, the expected articulation angle is calculated by comprehensively considering the steering parameters, driving parameters, load parameters and tracking parameters. The calculated expected articulation angle has higher accuracy. The expected articulation angle is used to adjust the articulation angle of the vehicle, thereby better improving the accuracy of lateral control of the articulated unmanned vehicle.

[0027] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0029] Figure 1 A block diagram of a lateral control system for an articulated unmanned vehicle in a coal mine provided by an embodiment of the present invention;

[0030] Figure 2 A schematic diagram of the arrangement of some components of a lateral control system for an articulated unmanned vehicle in an underground coal mine provided by an embodiment of the present invention;

[0031] Figure 3 A cross-sectional view of a steering control hydraulic cylinder provided in an embodiment of the present invention;

[0032] Figure 4 A schematic diagram of the connection between the front vehicle body and the rear vehicle body provided by an embodiment of the present invention;

[0033] Figure 5 The present invention is a flowchart of a method for lateral control of an articulated unmanned vehicle in an underground coal mine provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0034] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The implementations described in the following exemplary embodiments do not represent all implementations consistent with the embodiments of the present invention. Instead, they are merely examples of devices and methods consistent with some aspects of the embodiments of the present invention as detailed in the appended claims.

[0035] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0036] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined. It should also be understood that the term "and / or" used in the present invention refers to and includes any or all possible combinations of one or more associated listed items.

[0037] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0038] The present invention provides a lateral control system and method for an articulated unmanned vehicle in an underground coal mine, so as to improve the accuracy of lateral control of the articulated unmanned vehicle.

[0039] In a first embodiment, Figure 1 The block diagram of a lateral control system of an articulated unmanned vehicle in a coal mine provided by an embodiment of the present invention. The lateral control system of an articulated unmanned vehicle in a coal mine in the present invention can be referred to as a control system. Figure 1 As shown, the lateral control system of the articulated unmanned vehicle in the coal mine includes a vehicle perception system, an environmental perception system, a vehicle decision controller, and a steering control device. The vehicle decision controller is connected to the vehicle perception system, the environmental perception system, and the steering control device respectively. Among them, the vehicle perception system includes a steering parameter perception device, a driving parameter perception device, and a load parameter perception device. The vehicle parameters are obtained through the vehicle perception system, and the vehicle parameters include driving parameters, steering parameters, load parameters, etc., and sent to the vehicle decision controller. The environmental perception system includes a tracking parameter perception device.

[0040] In this embodiment, the steering parameter sensing device is used to obtain the steering parameters of the vehicle, and the steering parameters include the actual articulation angle of the vehicle.

[0041] In this embodiment, the steering parameter sensing device includes a first steering cylinder stroke sensor and a second steering cylinder stroke sensor; the first steering cylinder stroke sensor and the second steering cylinder stroke sensor are respectively installed in the corresponding steering control hydraulic cylinder, and are used to collect the cylinder stroke of the corresponding steering control hydraulic cylinder; the steering parameter sensing device calculates the actual articulation angle of the vehicle based on the cylinder stroke. Among them, the first steering cylinder stroke sensor and the second steering cylinder stroke sensor can adopt a wire distance measurement sensor.

[0042] Figure 2 This is a schematic diagram of the layout of some components of a lateral control system for an articulated unmanned vehicle in an underground coal mine provided by an embodiment of the present invention. Figure 3 A cross-sectional view of a steering control hydraulic cylinder provided in an embodiment of the present invention. Figure 4 A schematic diagram of the connection between the front vehicle body and the rear vehicle body provided in an embodiment of the present invention.

[0043] In this embodiment, if Figure 2 As shown, the articulated unmanned vehicle in a coal mine includes a front body and a rear body, which are hingedly connected, wherein the connection point between the front body and the rear body is a steering center, also called an articulation center. One end of a first steering control hydraulic cylinder 11 is hinged to the front body, and the other end of the first steering control hydraulic cylinder 11 is hinged to the rear body. One end of a second steering control hydraulic cylinder 12 is hinged to the front body, and the other end of the second steering control hydraulic cylinder 12 is hinged to the rear body. is the actual articulation angle of the vehicle.

[0044] The first steering cylinder stroke sensor 13 is installed in the first steering control hydraulic cylinder 11 and arranged inside one end of the first steering control hydraulic cylinder 11 hinged with the front vehicle body. The first steering cylinder stroke sensor 13 is used to collect the cylinder stroke of the first steering control hydraulic cylinder 11.

[0045] The second steering cylinder stroke sensor 14 is installed in the second steering control hydraulic cylinder 12 and arranged inside one end of the second steering control hydraulic cylinder 12 hinged with the front vehicle body. The second steering cylinder stroke sensor 14 is used to collect the cylinder stroke of the second steering control hydraulic cylinder 12 .

[0046] Taking the first steering cylinder stroke sensor 13 and the second steering cylinder stroke sensor 14 as an example, the position diagram of any steering cylinder stroke sensor of the first steering cylinder stroke sensor 13 and the second steering cylinder stroke sensor 14 in the corresponding steering control hydraulic cylinder is specifically shown in Figure 3 .like Figure 3 As shown, 1 is a steering control hydraulic cylinder, 2 is a piston rod of the steering control hydraulic cylinder, 3 is a pull-wire distance sensor, and 4 is a sensor pull wire. The sensor pull wire is used to connect the piston rod of the steering control hydraulic cylinder and the pull-wire distance sensor.

[0047] The actual articulation angle of the vehicle is calculated based on the cylinder stroke collected by the first steering cylinder stroke sensor 13 and the second steering cylinder stroke sensor 14. The calculation formula of the actual articulation angle of the vehicle satisfies:

[0048]

[0049] In the formula, is the actual articulation angle of the vehicle, L1 is the length of the first steering control hydraulic cylinder, L2 is the length of the second steering control hydraulic cylinder, and the length of the steering control hydraulic cylinder is the main length of the corresponding steering control hydraulic cylinder length. a is the distance from the hinge point of the first steering control hydraulic cylinder and the front body to the steering center, and b is the distance from the hinge point of the first steering control hydraulic cylinder and the rear body to the steering center (see Figure 4 ). In the present invention, the distance from the hinge point of the second steering control hydraulic oil cylinder and the front body to the steering center is equal to the distance from the hinge point of the first steering control hydraulic oil cylinder and the front body to the steering center, and the distance from the hinge point of the second steering control hydraulic oil cylinder and the rear body to the steering center is equal to the distance from the hinge point of the first steering control hydraulic oil cylinder and the rear body to the steering center.

[0050] In this embodiment, the driving parameter sensing device is used to obtain the driving parameters of the vehicle, and the driving parameters include the front vehicle body heading angle, the front vehicle body speed and the rear vehicle body speed.

[0051] In this embodiment, the driving parameter sensing device includes an inertial navigation device, a wheel speed meter and a radar device. The inertial navigation device is installed at the center of mass of the front vehicle body. Wheel speed meters are arranged on the front vehicle body and the rear vehicle body. The radar device is installed on the sides of the front vehicle body and the rear vehicle body. The radar device is used to detect the distance between the front vehicle body and the rear vehicle body and the coal wall of the driving lane, so as to warn whether the vehicle hits the wall during lateral control. The driving parameters also include the distance between the front vehicle body and the rear vehicle body and the coal wall of the driving lane.

[0052] like Figure 2 As shown, an inertial navigation device 21 is installed at the center of mass of the front vehicle body to obtain the heading angle of the front vehicle body. Multiple wheel speedometers 22 are installed on the front vehicle body to obtain the speed of the front vehicle body, and multiple wheel speedometers 22 (not shown) are also installed on the rear vehicle body to obtain the speed of the rear vehicle body. Multiple millimeter wave radars 23 are installed on the sides of the front vehicle body and the rear vehicle body to detect the distance between the front vehicle body and the rear vehicle body and the coal wall of the driving lane, so as to warn whether the vehicle hits the wall during lateral control.

[0053] In this embodiment, the load parameter sensing device is used to obtain the load parameters of the vehicle, which include the load weight and the center of mass position of the rear vehicle body. Figure 2 As shown, on the frame hinged at the bottom of the rear body load bucket, weighing sensors 31 are symmetrically arranged front and rear, with a total of 4 being arranged, so as to obtain the load weight and the center of mass position of the rear body.

[0054] In this embodiment, the tracking parameter sensing device is used to obtain the tracking parameters of the vehicle, which include the vehicle's driving trajectory, and the heading error and lateral error of the vehicle's driving distance from the preview point. Specifically, the tracking parameter sensing device uses a binocular camera to generate point cloud data to construct a positioning map, calculates the vehicle's unmanned driving control driving trajectory, and then obtains the heading error and lateral error of the vehicle's driving distance from the preview point. The tracking parameter sensing device sends the obtained vehicle's current driving position and the heading error and lateral error of the planned trajectory preview point to the vehicle decision controller.

[0055] In this embodiment, the vehicle decision controller is used to calculate the expected articulation angle based on the steering parameter, the driving parameter, the load parameter, and the tracking parameter. Specifically, the vehicle decision controller calculates the expected articulation angle based on the current position of the vehicle's driving trajectory and the heading error and lateral error of the preview point of the planned trajectory, the current speed of the vehicle, the heading angle, the articulation angle, etc., and sends the expected articulation angle to the steering control device.

[0056] In some embodiments, considering the risk of hitting the wall, the vehicle decision controller is also used to fine-tune the expected articulation angle based on the heading error and lateral error between the vehicle's current driving trajectory point position and the next preview point of the planned trajectory, as well as the distance between the front and rear bodies and the coal wall of the driving lane, so as to use the fine-tuned expected articulation angle to participate in subsequent control, so as to avoid hitting the wall while achieving precise control. Specifically, during the lateral control of the vehicle, the heading error and lateral error between the vehicle's driving trajectory point position and the next preview point of the planned trajectory are continuously obtained through the tracking parameter sensing device, and the distance between the front and rear bodies and the coal wall of the driving lane is monitored through the millimeter-wave radar of the driving parameter sensing device. The vehicle decision controller continuously calculates and adjusts the expected articulation angle of the vehicle to complete the lateral control of the vehicle laterally.

[0057] In this embodiment, the vehicle decision controller is also used to calculate the vehicle turning radius based on the expected articulation angle, and control the rotation of the wheels of the rear vehicle body based on the vehicle turning radius.

[0058] In this embodiment, the steering control device is used to adjust the articulation angle of the vehicle based on the desired articulation angle to achieve lateral control of the vehicle.

[0059] In this embodiment, the steering control device includes a first steering control hydraulic cylinder, a second steering control hydraulic cylinder, a controller, and a cylinder control valve. The controller calculates the first length of the first steering control hydraulic cylinder and the second length of the second steering control hydraulic cylinder based on the desired articulation angle, and adjusts the cylinder stroke of the corresponding steering control hydraulic cylinder through the cylinder control valve based on the first length and the second length to achieve precise adjustment of the vehicle's articulation angle.

[0060] The calculation formula for the first length and the second length is:

[0061]

[0062] Wherein, L1* is the first length, L2* is the second length, a is the distance from the hinge point of the first steering control hydraulic cylinder and the front body to the steering center, and b is the distance from the hinge point of the first steering control hydraulic cylinder and the rear body to the steering center. The distance from the hinge point of the second steering control hydraulic cylinder and the front body to the steering center is equal to the distance from the hinge point of the first steering control hydraulic cylinder and the front body to the steering center, and the distance from the hinge point of the second steering control hydraulic cylinder and the rear body to the steering center is equal to the distance from the hinge point of the first steering control hydraulic cylinder and the rear body to the steering center. is the desired articulation angle. α is the angle between the line between the articulation center and the hinge point of the first steering control hydraulic cylinder and the front body and the vertical line of the vehicle. The angle between the line between the articulation center and the hinge point of the first steering control hydraulic cylinder and the rear body and the vertical line of the vehicle, the angle between the line between the articulation center and the hinge point of the second steering control hydraulic cylinder and the front body and the vertical line of the vehicle, and the angle between the line between the articulation center and the hinge point of the second steering control hydraulic cylinder and the rear body and the vertical line of the vehicle are all equal to the angle α between the line between the articulation center and the hinge point of the first steering control hydraulic cylinder and the front body and the vertical line of the vehicle. In summary, after obtaining the desired articulation angle calculated by the vehicle decision controller, the controller calculates the first length and the second length, and controls the vehicle articulation angle through the cylinder control valve; and according to the data of the first steering cylinder stroke sensor and the second steering cylinder stroke sensor, when the first steering control hydraulic cylinder and the second steering control hydraulic cylinder reach the corresponding first length or second length, the cylinder control valve is closed to accurately control the articulation angle, thereby completing the lateral control of the underground articulated unmanned vehicle.

[0063] In this embodiment, considering that after the corresponding steering control hydraulic cylinder is controlled and adjusted to the first length and the second length, there is still a system inertia factor that makes the steering control hydraulic cylinder length not accurately equal to the first length or the second length, the steering control device also includes a first steering pressure sensor, a second steering pressure sensor and a prediction model; the first steering pressure sensor and the second steering pressure sensor are used to collect the cylinder pressure of the corresponding steering control hydraulic cylinder; the input of the prediction model is the cylinder stroke and the cylinder pressure, and the output is the closing position and closing time of the cylinder control valve; when the first length and the second length are calculated, the cylinder stroke and the cylinder pressure at the corresponding time are sent to the prediction model to obtain the required closing position and closing time; when the position and time of the cylinder control valve reach the required closing position and closing time, the cylinder control valve is controlled to close.

[0064] Specifically, the first steering cylinder stroke sensor, the first steering pressure sensor, the second steering cylinder stroke sensor, and the second steering pressure sensor are used as the input variables of the model. According to the cylinder stroke and cylinder pressure, the cylinder control valve is closed in advance when the cylinder length is about to reach the set length, and the cylinder length is precisely controlled through the inertia of the hydraulic system. The iterative control algorithm is used to train the model, and the closing position and closing time of the cylinder control valve at the set length are calculated to achieve precise control of the vehicle articulation angle.

[0065] The following is an embodiment of the method of the present invention. For details not disclosed in the embodiment of the method of the present invention, please refer to the system embodiment of the present invention. The method embodiment of the present invention proposes a method for lateral control of an articulated unmanned vehicle in a coal mine. The method for lateral control of an articulated unmanned vehicle in a coal mine utilizes the lateral control system of the articulated unmanned vehicle in a coal mine of the above system embodiment. The method for lateral control of an articulated unmanned vehicle in a coal mine of the present invention can be referred to as a control method.

[0066] Figure 5 The present invention is a flowchart of a method for lateral control of an articulated unmanned vehicle in an underground coal mine provided by an embodiment of the present invention.

[0067] like Figure 5 As shown, the lateral control method of the articulated unmanned vehicle in a coal mine comprises:

[0068] Step S101, obtaining the steering parameters, driving parameters, load parameters, and tracking parameters of the vehicle; the steering parameters include the actual articulation angle of the vehicle; the driving parameters include the heading angle of the front vehicle body, the front vehicle body speed, and the rear vehicle body speed; the load parameters include the load weight; the tracking parameters include the driving trajectory of the vehicle, and the heading error and lateral error of the vehicle from the preview point;

[0069] Step S102, calculating a desired articulation angle based on the steering parameter, the driving parameter, the load parameter, and the tracking parameter;

[0070] Step S103, adjusting the articulation angle of the vehicle based on the desired articulation angle to achieve lateral control of the vehicle.

[0071] In some embodiments, the driving parameters also include the distances between the front vehicle body and the rear vehicle body and the coal wall of the driving tunnel, and the control method also includes fine-tuning the desired articulation angle based on the heading error and lateral error between the current driving trajectory point position of the vehicle and the next preview point of the planned trajectory, and the distances between the front vehicle body and the rear vehicle body and the coal wall of the driving tunnel.

[0072] In some embodiments, the control method further includes calculating a turning radius of the vehicle based on the desired articulation angle, and controlling the rotation of the wheels of the rear vehicle body based on the turning radius of the vehicle.

[0073] In step S103, the articulation angle of the vehicle is adjusted based on the desired articulation angle, specifically including: calculating the first length of the first steering control hydraulic cylinder and the second length of the second steering control hydraulic cylinder based on the desired articulation angle, and adjusting the cylinder stroke of the corresponding steering control hydraulic cylinder through the cylinder control valve based on the first length and the second length to achieve adjustment of the articulation angle of the vehicle.

[0074] In some embodiments, the control method also includes sending the cylinder stroke and cylinder pressure at the corresponding moments to the prediction model to obtain the required closing position and closing time when the first length and the second length are calculated; when the position and time of the cylinder control valve reach the required closing position and closing time, controlling the cylinder control valve to close.

[0075] It should be noted that the aforementioned explanation of the embodiment of the lateral control system for an articulated unmanned vehicle in an underground coal mine is also applicable to the lateral control method for an articulated unmanned vehicle in an underground coal mine of this embodiment, and will not be repeated here.

[0076] The serial numbers of the above embodiments of the present invention are only for description and do not represent the advantages or disadvantages of the embodiments.

[0077] In the lateral control system and method of an articulated unmanned vehicle in an underground coal mine in an embodiment of the present invention, the system includes a steering parameter sensing device, a driving parameter sensing device, a load parameter sensing device, a tracking parameter sensing device, a vehicle decision controller, and a steering control device; the steering parameter sensing device is used to obtain the steering parameters of the vehicle, and the steering parameters include the actual articulation angle of the vehicle; the driving parameter sensing device is used to obtain the driving parameters of the vehicle, and the driving parameters include the heading angle of the front vehicle body, the front vehicle body speed, and the rear vehicle body speed; the load parameter sensing device is used to obtain the load parameters of the vehicle, and the load parameters include the load weight; the tracking parameter sensing device is used to obtain the tracking parameters of the vehicle, and the tracking parameters include the driving trajectory of the vehicle, and the heading error and lateral error of the vehicle from the preview point; the vehicle decision controller is used to calculate the expected articulation angle based on the steering parameter, driving parameter, load parameter, and tracking parameter; the steering control device is used to adjust the articulation angle of the vehicle based on the expected articulation angle to achieve lateral control of the vehicle. In this case, the expected articulation angle is calculated by integrating the steering parameters, driving parameters, load parameters, and tracking parameters. The calculated expected articulation angle has higher accuracy, and the expected articulation angle is used to adjust the articulation angle of the vehicle, thereby better improving the accuracy of lateral control of the articulated unmanned vehicle. The system and method of the present invention improve the unmanned driving trajectory control capability of coal mines and meet the unmanned driving control needs of coal mines.

[0078] The accompanying drawings show schematic diagrams of structures according to embodiments disclosed in the present invention. These figures are not drawn to scale, and some details are magnified and some details may be omitted for the purpose of clear expression. The shapes of various regions and layers shown in the figures and the relative sizes and positional relationships therebetween are only exemplary, and may deviate in practice due to manufacturing tolerances or technical limitations, and those skilled in the art may additionally design regions / layers with different shapes, sizes, and relative positions according to actual needs.

[0079] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution disclosed in the present invention can be achieved, and the present invention is not limited here.

[0080] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A lateral control system for an articulated unmanned vehicle in a coal mine, characterized in that: It includes a steering parameter sensing device, a driving parameter sensing device, a load parameter sensing device, a tracking parameter sensing device, a vehicle decision controller, and a steering control device; The steering parameter sensing device is used to obtain the steering parameters of the vehicle, and the steering parameters include the actual articulation angle of the vehicle; The driving parameter sensing device is used to obtain the driving parameters of the vehicle, and the driving parameters include the front vehicle body heading angle, the front vehicle body speed and the rear vehicle body speed; The load parameter sensing device is used to obtain the load parameters of the vehicle, and the load parameters include the load weight; The tracking parameter sensing device is used to obtain the tracking parameters of the vehicle, and the tracking parameters include the vehicle's driving trajectory, and the heading error and lateral error of the vehicle from the preview point; The vehicle decision controller is used to calculate the desired articulation angle based on the steering parameter, the driving parameter, the load parameter, and the tracking parameter; The steering control device is used to adjust the articulation angle of the vehicle based on the desired articulation angle to achieve lateral control of the vehicle.

2. The lateral control system of an articulated unmanned vehicle in a coal mine according to claim 1, characterized in that: The steering parameter sensing device includes a first steering cylinder stroke sensor and a second steering cylinder stroke sensor; the first steering cylinder stroke sensor and the second steering cylinder stroke sensor are respectively installed in the corresponding steering control hydraulic cylinder, and are used to collect the cylinder stroke of the corresponding steering control hydraulic cylinder; the steering parameter sensing device calculates the actual articulation angle of the vehicle based on the cylinder stroke.

3. The lateral control system of an articulated unmanned vehicle in a coal mine according to claim 2, characterized in that: The first steering cylinder stroke sensor and the second steering cylinder stroke sensor are wire-drawing distance measuring sensors.

4. The lateral control system of an articulated unmanned vehicle in a coal mine according to claim 1, characterized in that: The driving parameter sensing device includes an inertial navigation device, a wheel speed meter and a radar device. The inertial navigation device is installed at the center of mass of the front vehicle body. The wheel speed meter is arranged on the front vehicle body and the rear vehicle body. The radar device is installed on the sides of the front vehicle body and the rear vehicle body. The radar device is used to detect the distance between the front vehicle body and the rear vehicle body and the coal wall of the driving lane respectively, so as to warn whether the vehicle hits the wall during lateral control. The driving parameters also include the distance between the front vehicle body and the rear vehicle body and the coal wall of the driving lane respectively.

5. The lateral control system of an articulated unmanned vehicle in a coal mine according to claim 4, characterized in that: The vehicle decision controller is also used to fine-tune the expected articulation angle based on the heading error and lateral error between the vehicle's current driving trajectory point position and the next preview point of the planned trajectory, as well as the distances between the front and rear vehicle bodies and the coal wall of the driving lane respectively.

6. The lateral control system of an articulated unmanned vehicle in a coal mine according to claim 1, characterized in that: The steering control device includes a first steering control hydraulic cylinder, a second steering control hydraulic cylinder, a controller, and a cylinder control valve. The controller calculates a first length of the first steering control hydraulic cylinder and a second length of the second steering control hydraulic cylinder based on the desired articulation angle, and adjusts the cylinder stroke of the corresponding steering control hydraulic cylinder through the cylinder control valve based on the first length and the second length to achieve adjustment of the vehicle's articulation angle.

7. The lateral control system of an articulated unmanned vehicle in a coal mine according to claim 6, characterized in that: The steering control device also includes a first steering pressure sensor, a second steering pressure sensor and a prediction model; the first steering pressure sensor and the second steering pressure sensor are used to collect the cylinder pressure of the corresponding steering control hydraulic cylinder; the input of the prediction model is the cylinder stroke and the cylinder pressure, and the output is the closing position and closing time of the cylinder control valve; when the first length and the second length are calculated, the cylinder stroke and the cylinder pressure at the corresponding time are sent to the prediction model to obtain the required closing position and closing time; when the position and time of the cylinder control valve reach the required closing position and closing time, the cylinder control valve is controlled to close.

8. The lateral control system of an articulated unmanned vehicle in a coal mine according to claim 1, characterized in that: The vehicle decision controller is also used to calculate the vehicle turning radius based on the expected articulation angle, and control the rotation of the wheels of the rear vehicle body based on the vehicle turning radius.

9. A method for lateral control of an articulated unmanned vehicle in a coal mine, characterized in that: The method is applicable to the lateral control system of an articulated unmanned vehicle in an underground coal mine as claimed in any one of claims 1 to 8, and comprises: Obtaining the steering parameters, driving parameters, load parameters, and tracking parameters of the vehicle; the steering parameters include the actual articulation angle of the vehicle; the driving parameters include the heading angle of the front vehicle body, the front vehicle body speed, and the rear vehicle body speed; the load parameters include the load weight; the tracking parameters include the driving trajectory of the vehicle, and the heading error and lateral error of the vehicle from the preview point; Calculate a desired articulation angle based on the steering parameter, the driving parameter, the load parameter, and the tracking parameter; The articulation angle of the vehicle is adjusted based on the desired articulation angle to achieve lateral control of the vehicle.

10. The method for lateral control of an articulated unmanned vehicle in an underground coal mine according to claim 9, characterized in that: The driving parameters also include the distances between the front vehicle body and the rear vehicle body and the coal wall of the driving lane respectively. The method also includes fine-tuning the expected articulation angle based on the heading error and lateral error between the vehicle's current driving trajectory point position and the next preview point of the planned trajectory, and the distances between the front vehicle body and the rear vehicle body and the coal wall of the driving lane respectively.

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