A Longitudinal Low-Speed Smooth Control Method and System for Driverless Mining Trucks

Abstract

The present invention provides a longitudinal low-speed stable control method and system for an unmanned mining truck. The method includes: obtaining real-time driving data of the unmanned mining truck; establishing a minimum throttle statistical table based on throttle, throttle feedback, and torque feedback data, and calculating the minimum throttle value through processing the minimum throttle statistical table; obtaining a control signal; judging the driving state of the unmanned mining truck according to the pitch angle and gear. When the driving state is uphill or on flat road, performing main throttle control according to the minimum throttle value, expected throttle / expected brake, expected speed, and the speed of the mining truck; when the driving state is downhill, performing main brake control according to the expected throttle / expected brake, expected speed, and the speed of the mining truck. Through online processing of the minimum throttle statistical table, the minimum throttle value is calculated and can be updated in real time, which can ensure the stable power and versatility of vehicle operation for different mining trucks.

Description

Technical Field

[0001] The present invention belongs to the field of construction machinery and relates to a longitudinal low-speed stable control method and system for unmanned mining trucks. Background Art

[0002] Unmanned mining trucks are usually used in open-pit mines and are responsible for the task of transporting mining materials. With the development of science and technology and the maturity of driverless technology, the demand for unmanned mining trucks is increasing in open-pit mines with harsh or remote regional environments. The longitudinal control effect of unmanned mining trucks is directly related to the driving stability, transportation efficiency and energy consumption. Compared with ordinary cars, mining trucks are heavier and carry more loads. Especially for large mining trucks in mines, the throttle feedback and torque feedback are slow, and even zero torque occurs at low throttle. Whether using traditional PID control or longitudinal algorithms based on motor characteristics, unmanned mining trucks will experience insufficient throttle or frequent switching between throttle and braking during low-speed driving.

[0003] There are mainly the following three problems:

[0004] 1. When the throttle feedback is below a certain value, the torque feedback is zero, and the minimum throttle value of each mining truck is different;

[0005] 2. When the throttle value calculated by the longitudinal algorithm is less than the minimum throttle value, the unmanned mining truck has no power output, resulting in unstable driving of the unmanned mining truck, which has a greater impact on the unmanned mining truck during low-speed driving;

[0006] 3. When the speed error of the unmanned mining truck is small and no throttle output is required, due to the slow throttle feedback lagging behind the throttle output, there will be a phenomenon that the output torque is still large when the throttle output is zero, resulting in frequent switching between throttle and braking. Especially during low-speed driving, the unmanned mining truck drives unstably, with low efficiency and energy waste. Summary of the Invention

[0007] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a longitudinal low-speed stable control method and system for unmanned mining trucks. By online processing of the minimum throttle statistical table, the minimum throttle value is calculated and can be updated in real time, which can ensure stable power and universality for different mining trucks.

[0008] To achieve the above object, the present invention is implemented by the following technical solutions:

[0009] In the first aspect, the present invention provides a longitudinal low-speed stable control method for unmanned mining trucks, including the following steps:

[0010] Obtain real-time driving data of the unmanned mining truck; the unmanned mining truck driving data includes throttle, throttle feedback, torque feedback data, truck speed and pitch angle;

[0011] Establish a minimum throttle statistical table based on the throttle, throttle feedback, and torque feedback data, and calculate the minimum throttle value through processing the minimum throttle statistical table;

[0012] Obtain a control signal, where the control signal includes the desired throttle / desired brake, desired speed, and gear;

[0013] Judge the driving state of the unmanned mining truck according to the pitch angle and gear. When the driving state is uphill or on flat ground, perform main throttle control according to the minimum throttle value, desired throttle / desired brake, desired speed, and truck speed; when the driving state is downhill, perform main brake control according to the desired throttle / desired brake, desired speed, and truck speed.

[0014] Furthermore, establishing a minimum throttle statistical table based on the throttle, throttle feedback, and torque feedback data, and calculating the minimum throttle value through processing the minimum throttle statistical table includes:

[0015] S1. Collect the data of throttle, throttle feedback, and torque feedback in each operation cycle when the unmanned mining truck is driving at low speed, and store them in the minimum throttle statistical table;

[0016] S2. Filter out the driving data in the minimum throttle statistical table where the throttle error exceeds the preset value or the torque feedback is zero; the throttle error is the difference between the throttle and the throttle feedback;

[0017] S3. Re-arrange the minimum throttle statistical table in ascending order with the throttle feedback as the index;

[0018] S4. Take out the throttle data of the first several rows of the minimum throttle statistical table, and the calculated average value is the minimum throttle value;

[0019] S5. Update the minimum throttle statistical table in real time and calculate the minimum throttle value.

[0020] Furthermore, the method for judging the driving state of the unmanned mining truck according to the pitch angle and gear includes:

[0021] Judge the driving state of the unmanned mining truck based on the average pitch angle and gear collected in consecutive n operation cycles, where n is the number of operation cycles when the continuous driving distance of the unmanned mining truck is the wheelbase of the truck.

[0022] Furthermore, the calculation method of n is:

[0023] L≤L(V1+V2+…+V n )

[0024] where L is the distance between the front and rear axles of the truck, T is the operation cycle, and V n is the truck speed collected in each operation cycle;

[0025] When the accumulated distance is greater than L, calculate the average pitch angle of these n operating cycles.

[0026] Furthermore, determine the driving state of the driverless mining truck based on the average pitch angle and gear position collected in consecutive n operating cycles, including:

[0027] When the average pitch angle is greater than zero and the gear is in the forward position, the driving state of the driverless mining truck is downhill;

[0028] When the average pitch angle is less than or equal to zero and the gear is in the forward position, the driving state of the driverless mining truck is uphill or on a flat road;

[0029] When the average pitch angle is greater than or equal to zero and the gear is in the reverse position, the driving state of the driverless mining truck is uphill or on a flat road;

[0030] When the average pitch angle is less than zero and the gear is in the reverse position, the driving state of the driverless mining truck is downhill.

[0031] Furthermore, when the driving state is uphill or on a flat road, perform main throttle control based on the minimum throttle value, desired throttle / desired brake, desired speed, and the speed of the mining truck, including:

[0032] Judge whether the desired throttle is less than the minimum throttle value. If so, the throttle is the minimum throttle value; if not, the throttle is the desired throttle;

[0033] Judge whether the speed error is less than the main throttle speed error threshold. If so, the brake is the desired brake; if not, the brake is zero; the speed error is the difference between the desired speed and the speed of the mining truck;

[0034] Send the throttle / brake to the power system of the mining truck body for control;

[0035] When the driving state is downhill, perform main brake control based on the desired throttle / desired brake, desired speed, and the speed of the mining truck, including:

[0036] Judge whether the speed error is greater than the main brake speed error threshold. If so, the throttle is the desired throttle and the brake is the desired brake; if not, the throttle is zero and the brake is the desired brake;

[0037] Send the throttle / brake to the power system of the mining truck body for control.

[0038] Furthermore, the main throttle speed error threshold and the main brake speed error threshold are set according to the on-site commissioning effect of the driverless mining truck.

[0039] Second aspect, the present invention provides a longitudinal low-speed stable control system for an unmanned mining truck. The system is connected to a control module to obtain control signals; the system is connected to the mining truck body to obtain the driving data of the unmanned mining truck and output control information; the mining truck body includes an inertial navigation system and a power system; the driving data of the unmanned mining truck includes throttle, throttle feedback, torque feedback data, truck speed, and pitch angle; the control signals include desired throttle / desired brake, desired speed, and gear.

[0040] The system includes a minimum throttle online statistics module, a slope state module, a main throttle control module, and a main brake control module.

[0041] The minimum throttle online statistics module is used to establish a minimum throttle statistics table based on the throttle, throttle feedback, and torque feedback data, and calculate the minimum throttle value through the processing of the minimum throttle statistics table.

[0042] The slope state module is used to judge the driving state of the unmanned mining truck according to the pitch angle and gear. When the driving state is uphill or flat road, it sends the desired throttle / desired brake and desired speed to the main throttle control module. When the driving state is downhill, it sends the desired throttle / desired brake and desired speed to the main brake control module.

[0043] The main throttle control module is used to perform main throttle control according to the minimum throttle value, desired throttle / desired brake, desired speed, and truck speed, and output throttle / brake to the power system of the mining truck body.

[0044] The main brake control module is used to perform main brake control according to the desired throttle / desired brake, desired speed, and truck speed, and output throttle / brake to the power system of the mining truck body.

[0045] Furthermore, the control method of the system includes:

[0046] When the unmanned mining truck is driving at a low speed, the system receives the desired throttle / desired brake, desired speed, gear, truck speed, pitch angle, and throttle feedback.

[0047] The minimum throttle online statistics module establishes a minimum throttle statistics table based on the received throttle, throttle feedback, and torque feedback, and updates the minimum throttle value in real time and sends it to the main throttle control module.

[0048] The slope state module judges the driving state of the unmanned mining truck according to the gear and the average pitch angle. If the driving state is uphill or flat road, it sends the desired throttle / desired brake to the main throttle control module. If the driving state is downhill, it sends the desired throttle / desired brake to the main brake control module.

[0049] If the driverless mining truck is driving at a low speed on an uphill or flat road, the main throttle control module determines whether the desired throttle is less than the minimum throttle value. If so, the throttle is the minimum throttle value; if not, the throttle is the desired throttle. It determines whether the speed error is less than the main throttle speed error threshold. If so, the brake is the desired brake; if not, the brake is zero. Then it sends the throttle / brake to the powertrain of the mining truck body.

[0050] If the driverless mining truck is driving at a low speed downhill, the main brake control module determines whether the speed error is greater than the main brake speed error threshold. If so, the throttle is the desired throttle and the brake is the desired brake; if not, the throttle is zero and the brake is the desired brake. Then it sends the throttle / brake to the powertrain of the mining truck body.

[0051] Furthermore, the method for the minimum throttle online statistics module to calculate the minimum throttle value includes:

[0052] S1. Collect the data of throttle, throttle feedback, and torque feedback for each operation cycle during the low-speed driving of the driverless mining truck, and store them in the minimum throttle statistical table;

[0053] S2. Filter out the driving data in the minimum throttle statistical table where the throttle error exceeds the preset value or the torque feedback is zero. The throttle error is the difference between the throttle and the throttle feedback;

[0054] S3. Rearrange the minimum throttle statistical table in ascending order with the throttle feedback as the index;

[0055] S4. Take out the throttle data of the first several rows in the minimum throttle statistical table, and calculate the mean value as the minimum throttle value;

[0056] S5. Update the minimum throttle statistical table in real time and calculate the minimum throttle value.

[0057] Furthermore, the method for the slope state module to determine the driving state of the driverless mining truck according to the pitch angle and gear includes:

[0058] Determine the driving state of the driverless mining truck based on the mean pitch angle and gear collected in consecutive n operation cycles. n is the number of operation cycles when the consecutive driving distance of the driverless mining truck is the wheelbase of the mining truck. The calculation formula of n is:

[0059] L ≤ T(V1 + V2 + … + V n )

[0060] where L is the distance between the front and rear axles of the mining truck, T is the operation cycle, and V n is the speed of the mining truck collected in each operation cycle. When the accumulated distance is greater than L, calculate the mean pitch angle of these n operation cycles.

[0061] When the mean pitch angle is greater than zero and the gear is in forward, the driving state of the driverless mining truck is downhill;

[0062] When the average pitch angle is less than or equal to zero and the gear is in the forward position, the driving state of the driverless mining truck is uphill or on flat ground;

[0063] When the average pitch angle is greater than or equal to zero and the gear is in the reverse position, the driving state of the driverless mining truck is uphill or on flat ground;

[0064] When the average pitch angle is less than zero and the gear is in the reverse position, the driving state of the driverless mining truck is downhill.

[0065] Compared with the prior art, the beneficial effects achieved by the present invention are as follows:

[0066] 1. By processing the minimum throttle statistical table, the minimum throttle value is calculated and can be updated in real time, which can ensure stable power and universality for different mining trucks.

[0067] 2. The present invention accurately locates the driving state of the driverless mining truck by calculating the average pitch angle and judging the gear for the bumpy transportation route in the mine, avoiding overly frequent control switching caused by rough mountain roads.

[0068] 3. By controlling with the main throttle when driving uphill or on flat ground and with the main brake when driving downhill, the frequent switching of the throttle and brake is avoided, ensuring the smoothness of the low-speed driving of the driverless mining truck and achieving the purpose of high efficiency and energy saving. BRIEF DESCRIPTION OF THE DRAWINGS

[0069] Figure 1 It is a longitudinal low-speed smooth control system diagram of a driverless mining truck;

[0070] Figure 2 It is a longitudinal low-speed smooth control method flowchart of a driverless mining truck. DETAILED DESCRIPTION OF THE INVENTION

[0071] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present invention and cannot be used to limit the protection scope of the present invention.

[0072] Embodiment 1:

[0073] This embodiment provides a longitudinal low-speed smooth control method for a driverless mining truck. This method is based on a driverless mining truck system, which includes a control module for outputting control signals and a mining truck body for providing driving data of the driverless mining truck and executing the control method.

[0074] As Figure 2 shown, this control method includes the following steps:

[0075] Obtain real-time driving data of the driverless mining truck; the driving data of the driverless mining truck includes throttle, throttle feedback, torque feedback data, mining truck speed, and pitch angle;

[0076] Establish a minimum throttle statistics table based on throttle, throttle feedback, and torque feedback data, and calculate the minimum throttle value through processing the minimum throttle statistics table;

[0077] Obtain control signals, which include desired throttle / desired brake, desired speed, and gear position;

[0078] Judge the driving state of the unmanned mining truck according to the pitch angle and gear position. When the driving state is uphill or on flat road, perform main throttle control according to the minimum throttle value, desired throttle / desired brake, desired speed, and the speed of the mining truck; when the driving state is downhill, perform main brake control according to the desired throttle / desired brake, desired speed, and the speed of the mining truck.

[0079] Specifically, establishing a minimum throttle statistics table based on throttle, throttle feedback, and torque feedback data, and calculating the minimum throttle value through processing the minimum throttle statistics table includes:

[0080] S1. Collect the data of throttle, throttle feedback, and torque feedback in each operation cycle when the unmanned mining truck is driving at low speed, and store them in the minimum throttle statistics table;

[0081] S2. Filter out the driving data in the minimum throttle statistics table where the throttle error exceeds the preset value or the torque feedback is zero; the throttle error is the difference between the throttle and the throttle feedback; the preset value can be adjusted according to the actual situation.

[0082] S3. Rearrange the minimum throttle statistics table in ascending order with the throttle feedback as the index;

[0083] S4. Take out the throttle data of the first several rows of the minimum throttle statistics table, and calculate the mean value as the minimum throttle value;

[0084] S5. Update the minimum throttle statistics table in real time and calculate the minimum throttle value.

[0085] Specifically, the method for judging the driving state of the unmanned mining truck according to the pitch angle and gear position includes:

[0086] Judge the driving state of the unmanned mining truck based on the mean pitch angle and gear position collected in consecutive n operation cycles, where n is the number of operation cycles when the continuous driving distance of the unmanned mining truck is the wheelbase of the mining truck.

[0087] The calculation method of n is:

[0088] L≤L(V1+V2+…+V n )

[0089] where L is the distance between the front and rear axles of the mining truck, T is the operation cycle, and V n is the speed of the mining truck collected in each operation cycle;

[0090] When the accumulated distance is greater than L, calculate the average pitch angle of these n operating cycles.

[0091] Use the average pitch angle and gear position collected in consecutive n operating cycles to determine the driving state of the driverless mining truck, including:

[0092] When the average pitch angle is greater than zero and the gear position is forward, the driving state of the driverless mining truck is downhill;

[0093] When the average pitch angle is less than or equal to zero and the gear position is forward, the driving state of the driverless mining truck is uphill or flat road;

[0094] When the average pitch angle is greater than or equal to zero and the gear position is reverse, the driving state of the driverless mining truck is uphill or flat road;

[0095] When the average pitch angle is less than zero and the gear position is reverse, the driving state of the driverless mining truck is downhill.

[0096] Specifically, when the driving state is uphill or flat road, perform main throttle control according to the minimum throttle value, desired throttle / desired brake, desired speed, and the speed of the mining truck, including:

[0097] Judge whether the desired throttle is less than the minimum throttle value. If so, the throttle is the minimum throttle value; if not, the throttle is the desired throttle;

[0098] Judge whether the speed error is less than the main throttle speed error threshold. If so, the brake is the desired brake; if not, the brake is zero; the speed error is the difference between the desired speed and the speed of the mining truck;

[0099] Send the throttle / brake to the power system of the mining truck body for control;

[0100] When the driving state is downhill, perform main brake control according to the desired throttle / desired brake, desired speed, and the speed of the mining truck, including:

[0101] Judge whether the speed error is greater than the main brake speed error threshold. If so, the throttle is the desired throttle and the brake is the desired brake; if not, the throttle is zero and the brake is the desired brake;

[0102] Send the throttle / brake to the power system of the mining truck body for control.

[0103] Specifically, the main throttle speed error threshold and the main brake speed error threshold are set according to the on-site commissioning effect of the driverless mining truck.

[0104] Embodiment 2:

[0105] This embodiment provides a longitudinal low-speed stable control system for a driverless mining truck. The following is an explanation of the present invention in conjunction with the attached Figure 1-2 and specific embodiments:

[0106] An unmanned mining truck longitudinal low-speed stable control system, as Figure 1 shown. This system is respectively connected to the mining truck body and the longitudinal control algorithm module. The mining truck body includes a power system and an inertial navigation system.

[0107] Taking the driving and transportation of an unmanned mining truck in an open-pit mine as an example. The power system of the mining truck body includes the engine, generator, frequency converter, discharge resistor, in-wheel motor, accelerator pedal, and brake pedal of the mining truck. The inertial navigation system receives the positioning base station signal in the form of inertial navigation plus radio station combination, and can accurately provide the speed and pitch angle of the unmanned mining truck. The longitudinal control algorithm module can use a common mining truck control module, adopt control based on motor characteristics, calculate the expected throttle and expected brake to be mutually exclusive, and does not allow both the expected throttle and the expected brake to have values greater than zero at the same time. The maximum speed error in the speed stable stage is controlled within 2 km / h.

[0108] This system includes:

[0109] The minimum throttle online statistics module is used to establish a minimum throttle statistical table with the received throttle, throttle feedback, and torque feedback data when the unmanned mining truck is driving at a low speed, and statistically calculate the minimum throttle value through the processing of the minimum throttle statistical table and send it to the main throttle control module.

[0110] The slope state module is used to receive the expected throttle / expected brake, expected speed, gear, and the pitch angle sent by the mining truck body sent by the longitudinal control algorithm module, and judge the driving state of the unmanned mining truck based on the average pitch angle and gear collected in consecutive n operating cycles. When the driving state is uphill or flat road, send the expected throttle / expected brake and expected speed to the main throttle control module. When the driving state is downhill, send the expected throttle / expected brake and expected speed to the main brake control module

[0111] The main throttle control module is used to receive the expected throttle / expected brake and expected speed sent by the slope state module, judge whether the throttle is the expected throttle or the minimum throttle value according to the expected throttle, and judge that the brake is the expected brake or zero according to the speed error and the main throttle speed error threshold, and output the throttle / brake to the power system of the mining truck body.

[0112] The main brake control module is used to receive the expected throttle / expected brake and expected speed sent by the slope state module, judge that the throttle is the expected throttle or zero according to the speed error and the main brake speed error threshold, and the brake is the expected brake. Output the throttle / brake to the power system of the mining truck body.

[0113] Specifically, when the unmanned mining truck is driving at a low speed, the minimum throttle online statistics module receives driving data such as throttle, throttle feedback, and torque feedback in each operating cycle, and establishes a minimum throttle statistical table with throttle error, throttle feedback, and torque feedback. The processing of the minimum throttle statistical table includes the following steps:

[0114] S1. The minimum throttle online statistics module collects the data of throttle, throttle feedback, and torque feedback for each operation cycle during the low-speed driving of the unmanned mining truck, and stores them in the minimum throttle statistics table;

[0115] S2. Filter the driving data in the minimum throttle statistics table where the throttle error exceeds the preset value or the torque feedback is zero;

[0116] S3. Rearrange the minimum throttle statistics table in ascending order with the throttle feedback as the index;

[0117] S4. Take out the throttle data of the first several rows in the minimum throttle statistics table, and calculate the mean value as the minimum throttle value;

[0118] S5. Update the minimum throttle statistics table in real time and calculate the minimum throttle value.

[0119] Specifically, the slope state module judges the driving state of the unmanned mining truck based on the mean pitch angle and gear collected in continuous n operation cycles. n is the number of operation cycles when the continuous driving distance of the unmanned mining truck is the wheelbase of the truck. The operation cycle of the unmanned mining truck is 0.1 second, and the wheelbase is 4 meters. According to the formula:

[0120] 4 ≤ 0.1 * (V1 + V2 + … + V n )

[0121] Calculate n. For example, when the unmanned mining truck is driving at a constant speed of 15 km / h, at the 10th operation cycle, the driving distance of the unmanned mining truck is greater than the wheelbase, and n is 10.

[0122] When the mean pitch angle is greater than zero and the gear is forward, the driving state of the unmanned mining truck is downhill;

[0123] When the mean pitch angle is less than or equal to zero and the gear is forward, the driving state of the unmanned mining truck is uphill or flat road;

[0124] When the mean pitch angle is greater than or equal to zero and the gear is reverse, the driving state of the unmanned mining truck is uphill or flat road;

[0125] When the mean pitch angle is less than zero and the gear is reverse, the driving state of the unmanned mining truck is downhill;

[0126] Specifically, when the unmanned mining truck is driving at low speed on an uphill or flat road, it is mainly controlled by the throttle. The main throttle control module receives the desired throttle / desired brake and desired speed sent by the slope state module, judges whether the throttle is the desired throttle or the minimum throttle value according to the desired throttle, and judges that the brake is the desired brake or zero according to the speed error and the main throttle speed error threshold, and outputs the throttle / brake to the power system of the truck body.

[0127] Specifically, when the driverless mining truck is driving at a low speed downhill, it is mainly controlled by braking. The braking control module receives the expected throttle / expected brake and expected speed sent by the slope state module, and determines whether the throttle is the expected throttle or zero, and the brake is the expected brake according to the speed error and the main braking speed error threshold. The throttle / brake is output to the power system of the mining truck body.

[0128] This embodiment also provides a longitudinal low-speed stable control method for a driverless mining truck, based on the longitudinal low-speed stable control system of the driverless mining truck, as Figure 2 shown, including the following steps:

[0129] S1. When the driverless mining truck is driving at a low speed, the system receives the driving data such as the expected throttle / expected brake, expected speed, gear, the speed of the mining truck collected by the mining truck body, pitch angle, and throttle feedback sent by the longitudinal control algorithm module.

[0130] S2. The minimum throttle online statistics module establishes a minimum throttle statistics table according to the received throttle, throttle feedback, and torque feedback, and updates the minimum throttle value in real time and sends it to the main throttle control module.

[0131] S3. The slope state module judges the driving state of the driverless mining truck according to the gear and the average value of the pitch angle. If the driving state is uphill or flat road, it sends the expected throttle / expected brake to the main throttle control module. If the driving state is downhill, it sends the expected throttle / expected brake to the main braking control module.

[0132] S4. If the driverless mining truck is driving at a low speed uphill or on a flat road, the driving of the driverless mining truck is mainly controlled by the throttle. The main throttle control module judges whether the expected throttle is less than the minimum throttle value according to the size of the expected throttle. If so, the throttle is the minimum throttle value. If not, the throttle is the expected throttle. It judges whether the speed error is less than the main throttle speed error threshold. If so, the brake is the expected brake. If not, the brake is zero. The throttle / brake is sent to the power system of the mining truck body.

[0133] S5. If the driverless mining truck is driving at a low speed downhill, the driving of the driverless mining truck is mainly controlled by braking. The main braking control module judges whether the speed error is greater than the main braking speed error threshold. If so, the throttle is the expected throttle and the brake is the expected brake. If not, the throttle is zero and the brake is the expected brake. The throttle / brake is sent to the power system of the mining truck body.

[0134] The method of this embodiment calculates the minimum throttle value through the processing of the minimum throttle statistics table, and can be updated in real time, which can ensure the stable power and versatility of the vehicle operation for different mining trucks.

[0135] For the bumpy transportation route in the mine, by calculating the average value of the pitch angle and judging the gear, the driving state of the driverless mining truck can be accurately located.

[0136] By adopting the control strategy of using the main throttle for driving on uphill or flat roads and the main brake for driving downhill, frequent switching between the throttle and the brake is avoided, ensuring the smoothness of the low-speed driving of the driverless mining truck and achieving the purpose of high efficiency and energy conservation.

[0137] The un-disclosed part of the present invention belongs to the prior art.

[0138] Those skilled in the art should understand that the embodiments of the present application can be provided as a method, a system, or a computer program product. Therefore, the present application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0139] The present application is described with reference to the flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or block in the flowchart and / or block diagram can be implemented by computer program instructions, and the combination of the processes and / or blocks in the flowchart and / or block diagram can also be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing devices generate a device for realizing the functions specified in one Figure 1 one process or multiple processes and / or blocks Figure 1 one block or multiple blocks.

[0140] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer-readable memory generate a manufactured product including an instruction device, and the instruction device realizes the functions specified in one Figure 1 one process or multiple processes and / or blocks Figure 1 one block or multiple blocks.

[0141] These computer program instructions can also be loaded onto a computer or other programmable data processing device, so that a series of operation steps are executed on the computer or other programmable device to generate a computer-implemented process, and thus the instructions executed on the computer or other programmable device provide steps for realizing the functions specified in one Figure 1 one process or multiple processes and / or blocks Figure 1 one block or multiple blocks.

[0142] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the technical principle of the present invention, several improvements and modifications can be made, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A longitudinal low-speed stable control method for driverless mining trucks, characterized in that, Including the following steps: Obtain real-time driving data of driverless mining trucks; the driverless mining truck driving data includes throttle, throttle feedback, torque feedback data, truck speed, and pitch angle; Establish a minimum throttle statistical table based on the throttle, throttle feedback, and torque feedback data, and calculate the minimum throttle value through processing of the minimum throttle statistical table; Obtain a control signal, the control signal including desired throttle / desired brake, desired speed, and gear; Judge the driving state of the driverless mining truck according to the pitch angle and gear. When the driving state is uphill or flat, perform main throttle control according to the minimum throttle value, desired throttle / desired brake, desired speed, and truck speed; when the driving state is downhill, perform main brake control according to the desired throttle / desired brake, desired speed, and truck speed; When the driving state is uphill or flat, performing main throttle control according to the minimum throttle value, desired throttle / desired brake, desired speed, and truck speed includes: Judge whether the desired throttle is less than the minimum throttle value. If so, the throttle is the minimum throttle value; if not, the throttle is the desired throttle; Judge whether the speed error is less than the main throttle speed error threshold. If so, the brake is the desired brake; if not, the brake is zero; the speed error is the difference between the desired speed and the truck speed; Send the throttle / brake to the power system of the truck body for control; When the driving state is downhill, performing main brake control according to the desired throttle / desired brake, desired speed, and truck speed includes: Judge whether the speed error is greater than the main brake speed error threshold. If so, the throttle is the desired throttle and the brake is the desired brake; if not, the throttle is zero and the brake is the desired brake; Send the throttle / brake to the power system of the truck body for control.

2. The longitudinal low-speed stable control method for driverless mining trucks according to claim 1, characterized in that Establishing a minimum throttle statistical table based on the throttle, throttle feedback, and torque feedback data, and calculating the minimum throttle value through processing of the minimum throttle statistical table includes: S1. Collect the data of throttle, throttle feedback, and torque feedback in each operation cycle when the driverless mining truck is driving at a low speed, and store them in the minimum throttle statistical table; S2. Filter out the driving data in the minimum throttle statistical table where the throttle error exceeds the preset value or the torque feedback is zero; the throttle error is the difference between the throttle and the throttle feedback; S3. Rearrange the minimum throttle statistical table in ascending order with the throttle feedback as the index; S4. Take out the throttle data of the first several rows of the minimum throttle statistical table, and the calculated average value is the minimum throttle value; S5. Update the minimum throttle statistical table in real time and calculate the minimum throttle value.

3. The longitudinal low-speed smooth control method for driverless mining trucks according to claim 1, characterized in that, The method for judging the driving state of the driverless mining truck according to the pitch angle and gear includes: Judge the driving state of the driverless mining truck based on the average pitch angle and gear collected in consecutive n operation cycles, where n is the number of operation cycles when the consecutive driving distance of the driverless mining truck is the wheelbase of the truck.

4. The longitudinal low-speed stable control method for driverless mining trucks according to claim 3, wherein, The calculation method of n is: L ≤ T(V1 + V2 + … + V n ) where L is the distance between the front and rear axles of the mining truck, T is the operating cycle, and V1 to V n are the speeds of the mining truck collected in the 1st to the nth operating cycles; When the accumulated distance is greater than L, calculate the average pitch angle of these n operation cycles.

5. The longitudinal low-speed smooth control method for driverless mining trucks according to claim 4, characterized in that Judging the driving state of the driverless mining truck based on the average pitch angle and gear collected in consecutive n operation cycles includes: When the average pitch angle is greater than zero and the gear is forward, the driving state of the driverless mining truck is downhill; When the average pitch angle is less than or equal to zero and the gear is forward, the driving state of the driverless mining truck is uphill or flat; When the average pitch angle is greater than or equal to zero and the gear is in reverse, the driving state of the driverless mining truck is uphill or on flat ground; When the average pitch angle is less than zero and the gear is in reverse, the driving state of the driverless mining truck is downhill.

6. A longitudinal low-speed stable control system for unmanned mining trucks, characterized in that, The system is connected to the control module to obtain control signals; the system is connected to the mining truck body to obtain the driving data of the driverless mining truck and output control information; the mining truck body includes an inertial navigation system and a power system; the driving data of the driverless mining truck includes throttle, throttle feedback, torque feedback data, truck speed, and pitch angle; the control signals include desired throttle / desired brake, desired speed, and gear; The system includes a minimum throttle online statistics module, a slope state module, a main throttle control module, and a main brake control module; The minimum throttle online statistics module is used to establish a minimum throttle statistical table based on the throttle, throttle feedback, and torque feedback data, and calculate the minimum throttle value through the processing of the minimum throttle statistical table; The slope state module is used to judge the driving state of the driverless mining truck according to the pitch angle and gear. When the driving state is uphill or on flat ground, it sends the desired throttle / desired brake and desired speed to the main throttle control module; when the driving state is downhill, it sends the desired throttle / desired brake and desired speed to the main brake control module; The main throttle control module is used to perform main throttle control according to the minimum throttle value, desired throttle / desired brake, desired speed, and truck speed, and output throttle / brake to the power system of the mining truck body; The main brake control module is used to perform main brake control according to the desired throttle / desired brake, desired speed, and truck speed, and output throttle / brake to the power system of the mining truck body; If the driverless mining truck is driving slowly uphill or on flat ground, the main throttle control module judges whether the desired throttle is less than the minimum throttle value according to the size of the desired throttle. If so, the throttle is the minimum throttle value; if not, the throttle is the desired throttle; it judges whether the speed error is less than the main throttle speed error threshold. If so, the brake is the desired brake; if not, the brake is zero; it sends the throttle / brake to the power system of the mining truck body; If the driverless mining truck is driving slowly downhill, the main brake control module judges whether the speed error is greater than the main brake speed error threshold. If so, the throttle is the desired throttle and the brake is the desired brake; if not, the throttle is zero and the brake is the desired brake; it sends the throttle / brake to the power system of the mining truck body.

7. The longitudinal low-speed stable control system for driverless mining trucks according to claim 6, wherein, The control method of the system includes: When the driverless mining truck is driving slowly, the system receives the desired throttle / desired brake, desired speed, gear, truck speed, pitch angle, and throttle feedback; The minimum throttle online statistics module establishes a minimum throttle statistical table according to the received throttle, throttle feedback, and torque feedback, and updates the minimum throttle value in real time and sends it to the main throttle control module; The slope state module judges the driving state of the driverless mining truck according to the gear and the average pitch angle; if the driving state is uphill or on flat ground, it sends the desired throttle / desired brake to the main throttle control module; if the driving state is downhill, it sends the desired throttle / desired brake to the main brake control module.

8. The longitudinal low-speed stable control system for unmanned mining trucks according to claim 7, characterized in that, The method for the minimum throttle online statistics module to calculate the minimum throttle value includes: S1. Collect the data of throttle, throttle feedback, and torque feedback for each operation cycle during the low-speed driving of the unmanned mining truck, and store them in the minimum throttle statistical table; S2. Filter out the driving data in the minimum throttle statistical table where the throttle error exceeds the preset value or the torque feedback is zero. The throttle error is the difference between the throttle and the throttle feedback; S3. Rearrange the minimum throttle statistical table in ascending order with the throttle feedback as the index; S4. Take out the throttle data of the first several rows of the minimum throttle statistical table, and calculate the mean value as the minimum throttle value; S5. Update the minimum throttle statistical table in real time and calculate the minimum throttle value.

9. The longitudinal low-speed stable control system for driverless mining trucks according to claim 7, wherein, The method for the slope state module to judge the driving state of the unmanned mining truck according to the pitch angle and the gear includes: Judge the driving state of the unmanned mining truck based on the mean pitch angle and the gear collected in consecutive n operation cycles. n is the number of operation cycles when the continuous driving distance of the unmanned mining truck is the wheelbase of the mining truck. The calculation formula of n is: L ≤ T(V1 + V2 + … + V n ) Where L is the distance between the front and rear axles of the mining truck, T is the operating cycle, and V1 to V n are the speeds of the mining truck collected in the 1st to nth operating cycles; when the accumulated distance is greater than L, calculate the average pitch angle of these n operating cycles; When the mean pitch angle is greater than zero and the gear is forward, the driving state of the unmanned mining truck is downhill; When the mean pitch angle is less than or equal to zero and the gear is forward, the driving state of the unmanned mining truck is uphill or flat road; When the mean pitch angle is greater than or equal to zero and the gear is reverse, the driving state of the unmanned mining truck is uphill or flat road; When the mean pitch angle is less than zero and the gear is reverse, the driving state of the unmanned mining truck is downhill.

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