An unmanned mining truck anti-skid system and control method

Abstract

The present invention discloses an unmanned mine truck start-up anti-slip system and control method, including a start-up acceleration statistics module and a start-up anti-slip control module; the start-up acceleration statistics module is used to collect the real-time speed of the unmanned mine truck at different expected speeds when starting on a flat road, calculate the start-up acceleration based on the real-time speed, and count the corresponding relationship between different expected speeds and the start-up acceleration, generate a start-up acceleration table and send it to the start-up anti-slip control module; the start-up anti-slip control module calculates the expected driving force based on the received expected speed and the start-up acceleration table, as well as the pitch angle of the unmanned mine truck and the unmanned mine truck loading weight, and further obtains the throttle amount or brake amount, and adds the obtained throttle amount or brake amount to the throttle amount or brake amount of the previous operation cycle and sends it to the power system of the unmanned mine truck. The present invention can ensure that the unmanned mine truck does not slip when starting and the speed control is stable.

Description

Technical Field

[0001] The present invention belongs to the field of engineering machinery, and in particular relates to an unmanned mining truck starting anti-skid system and a control method. Background Art

[0002] Unmanned mining trucks are becoming more and more popular in open-pit mines, and they are responsible for the transportation tasks of mines. Compared with manned mining trucks, unmanned mining trucks are more dangerous when they slip when starting. The traditional control method for unmanned vehicles starting on a slope is to multiply the error between the expected speed and the actual speed by a coefficient as the expected acceleration, and then query the corresponding throttle opening / brake pressure table through the expected acceleration and expected speed to determine the final throttle or brake output. Although this method can make the unmanned vehicle start quickly, it also has the following problems:

[0003] 1. The expected acceleration is calculated by multiplying the same coefficient under different expected accelerations. This coefficient is an empirical value and is not combined with the longitudinal control speed characteristics of the vehicle. This calculation method is not accurate enough and has no reference standard. Especially for vehicles such as mining trucks with large mass, heavy load, large inertia and slow starting speed, the first thing to do is to ensure the safety of starting without slipping, and the second is to ensure the stability of speed control when switching to the driving state after starting.

[0004] 2. Querying the corresponding throttle opening / brake pressure table by the expected acceleration and expected speed to determine the final throttle or brake output requires a lot of experimental tests, and requires high acceleration accuracy for the test vehicle. However, for unmanned mining trucks driving on bumpy roads in mining areas, it is very difficult to accurately collect acceleration, especially at high speeds, which leads to inaccurate tabulation. Once it is inaccurate, the vehicle may slip. Summary of the invention

[0005] In view of the above problems, the present invention proposes an unmanned mining truck starting anti-skid system and control method. Combined with the speed characteristics of the longitudinal control of the unmanned mining truck, the speed of starting on a flat road under different expected speeds is collected to make a starting acceleration table; the throttle amount or braking amount is calculated according to the driving force error, ensuring that the unmanned mining truck does not skid when starting and the speed is controlled smoothly.

[0006] In order to achieve the above technical objectives and the above technical effects, the present invention is implemented through the following technical solutions:

[0007] In a first aspect, the present invention provides an unmanned mining truck anti-skid system when starting, comprising: a starting acceleration statistics module and a starting anti-skid control module;

[0008] The starting acceleration statistics module is used to collect the real-time speed of the unmanned mining truck when starting at different expected speeds, calculate the starting acceleration based on the real-time speed, and calculate the corresponding relationship between different expected speeds and starting acceleration, generate a starting acceleration table and send it to the starting anti-slip control module;

[0009] The starting anti-skid control module calculates the expected driving force based on the received expected speed, the starting acceleration table, the pitch angle of the unmanned mining truck and the loading weight of the unmanned mining truck, and further obtains the throttle amount or the braking amount, and accumulates the obtained throttle amount or the braking amount with the throttle amount or the braking amount of the previous operation cycle and sends it to the power system of the unmanned mining truck.

[0010] Optionally, the start-up anti-slip control module includes: a desired acceleration submodule, a driving force error submodule, a driving force control submodule and an accumulation submodule connected in sequence;

[0011] The expected acceleration submodule is used to receive the expected speed sent by the decision module and the starting acceleration table sent by the starting acceleration statistics module, obtain the expected acceleration through a two-dimensional linear interpolation method, and transmit it to the driving force error submodule;

[0012] The driving force error submodule is used to receive the expected acceleration, the pitch angle of the unmanned mining truck and the loading weight of the unmanned mining truck, calculate the expected driving force required by the unmanned mining truck according to the vehicle dynamics model, and compare it with the received actual driving force of the unmanned mining truck to obtain the driving force error; judge whether the driving force error is greater than zero, if so, send the driving force error to the driving force control submodule, if not, send a control instruction to the hydraulic system, the hydraulic system releases the hydraulic brake device, and the unmanned mining truck enters the driving state;

[0013] The driving force control submodule is used to receive the driving force error sent by the driving force error submodule, obtain the throttle amount or the braking amount through the PID controller, and send it to the accumulation submodule;

[0014] The accumulation submodule is used to receive the throttle amount or brake amount sent by the driving force control submodule, accumulate the throttle amount or brake amount with the throttle amount or brake amount of the previous operation cycle to obtain the final throttle amount or brake amount, and send it to the power system of the unmanned mining truck.

[0015] Optionally, the calculation formula of the starting acceleration is:

[0016]

[0017] Where a is the starting acceleration, V n It is the speed collected when the unmanned mining truck starts the nth operation cycle, and T is the operation cycle of the unmanned mining truck.

[0018] Optionally, the statistical method for the corresponding relationship between the expected speed and the starting acceleration is:

[0019] The starting acceleration statistics module collects driving data once every set operating cycle, takes the actual speed of the unmanned mining truck from rest to driving t, and the acceleration calculated by the kinematic formula is the starting acceleration at the expected speed.

[0020] Optionally, the calculation formula of the driving force error is:

[0021] m=m 车 +m 载

[0022] F g =m·g·sinθ

[0023] F drive =F g +m·a

[0024] F error =F drive -F drive_now

[0025] Among them, m is the total mass of the unmanned mining truck, m 车 is the weight of the unmanned mining truck, m 载 F is the loading weight of the unmanned mining truck. drive is the expected driving force, F g is the component of gravity on the ramp, g is the acceleration of gravity, θ is the pitch angle of the unmanned mining truck, a is the starting acceleration, and F error is the driving force error, F drive_now The actual driving force of the unmanned mining truck uploaded by the mining truck’s main power system.

[0026] Optionally, the driving force error sent by the receiving driving force error submodule is used to obtain a throttle amount or a brake amount through a PID controller, and the calculation formula of the throttle amount or the brake amount is:

[0027]

[0028] Among them, U n is the throttle amount or brake amount calculated in the nth cycle, K P is the proportionality coefficient, K I is the integration coefficient, K D is the differential coefficient, F error (t) is the driving force error of the nth cycle, t = n·T, T is the operation cycle of the unmanned mining truck;

[0029] The calculation formula of the final throttle amount or brake amount is:

[0030] U total=U 1 +U 2 +…+U n

[0031] Among them, U total Calculate the accumulated value of the throttle amount or the brake amount for n operating cycles.

[0032] In a second aspect, the present invention provides a control method for an unmanned mining truck start-up anti-skid system, comprising:

[0033] The starting acceleration statistics module is used to collect the real-time speed of the unmanned mining truck when starting at different expected speeds on a flat road, the starting acceleration is calculated based on the real-time speed, and the corresponding relationship between different expected speeds and starting acceleration is statistically calculated. After generating a starting acceleration table, it is sent to the starting anti-slip control module;

[0034] The starting anti-skid control module calculates the expected driving force based on the received expected speed, starting acceleration table, pitch angle and loading weight of the unmanned mining truck, and further obtains the throttle amount or braking amount. The obtained throttle amount or braking amount is added to the throttle amount or braking amount of the previous operation cycle and sent to the power system of the unmanned mining truck.

[0035] Optionally, the start-up anti-slip control module includes: a desired acceleration submodule, a driving force error submodule, a driving force control submodule and an accumulation submodule connected in sequence;

[0036] The expected acceleration submodule is used to receive the expected speed sent by the decision module and the starting acceleration table sent by the starting acceleration statistics module, obtain the expected acceleration through a two-dimensional linear interpolation method, and transmit it to the driving force error submodule;

[0037] The driving force error submodule is used to receive the expected acceleration, the pitch angle of the unmanned mining truck and the loading weight of the unmanned mining truck, calculate the expected driving force required by the unmanned mining truck according to the vehicle dynamics model, and compare it with the received actual driving force of the unmanned mining truck to obtain the driving force error; judge whether the driving force error is greater than zero, if so, send the driving force error to the driving force control submodule, if not, send a control instruction to the hydraulic system, the hydraulic system releases the hydraulic brake device, and the unmanned mining truck enters the driving state;

[0038] The driving force control submodule is used to receive the driving force error sent by the driving force error submodule, obtain the throttle amount or the braking amount through the PID controller, and send it to the accumulation submodule;

[0039] The accumulation submodule is used to receive the throttle amount or brake amount sent by the driving force control submodule, accumulate the throttle amount or brake amount with the throttle amount or brake amount of the previous operation cycle to obtain the final throttle amount or brake amount, and send it to the power system of the unmanned mining truck.

[0040] Optionally, the calculation formula of the starting acceleration is:

[0041]

[0042] Where a is the starting acceleration, V n It is the speed collected when the unmanned mining truck starts the nth operation cycle, and T is the operation cycle of the unmanned mining truck.

[0043] Optionally, the statistical method for the corresponding relationship between the expected speed and the starting acceleration is:

[0044] The starting acceleration statistics module collects driving data once every set operating cycle, takes the actual speed of the unmanned mining truck from rest to driving t, and the acceleration calculated by the kinematic formula is the starting acceleration at the expected speed.

[0045] Optionally, the calculation formula of the driving force error is:

[0046] m=m 车 +m 载

[0047] F g =m·g·sinθ

[0048] F drive =F g +m·a

[0049] F error =F drive -F drive_now

[0050] Among them, m is the total mass of the unmanned mining truck, m 车 is the weight of the unmanned mining truck, m 载 F is the loading weight of the unmanned mining truck. drive is the expected driving force, F g is the component of gravity on the ramp, g is the acceleration of gravity, θ is the pitch angle of the unmanned mining truck, a is the starting acceleration, and F error is the driving force error, F drive_now The actual driving force of the unmanned mining truck uploaded by the mining truck’s main power system.

[0051] Optionally, the driving force error sent by the receiving driving force error submodule is used to obtain a throttle amount or a brake amount through a PID controller, and the calculation formula of the throttle amount or the brake amount is:

[0052]

[0053] Among them, U n is the throttle amount or brake amount calculated in the nth cycle, KP is the proportionality coefficient, K I is the integration coefficient, K D is the differential coefficient, F error (t) is the driving force error of the nth cycle, t = n·T, T is the operation cycle of the unmanned mining truck;

[0054] The calculation formula of the final throttle amount or brake amount is:

[0055] U total =U 1 +U 2 +…+U n

[0056] Among them, U total Calculate the accumulated value of the throttle amount or the brake amount for n operating cycles.

[0057] Compared with the prior art, the present invention has the following beneficial effects:

[0058] Since different longitudinal control algorithms have different data in the starting acceleration table, only by combining the speed characteristics of the unmanned vehicle's longitudinal control can the expected acceleration at the start be calculated more accurately. Moreover, when the starting state enters the driving state, it can be better integrated into the longitudinal control, and the starting to driving process is smoother.

[0059] The present invention realizes a starting mode in which the unmanned mine truck uses the flat road as a reference for starting on a slope through data collection and statistics of flat road starting, and the speed control is more stable.

[0060] The starting acceleration collection and statistical process of the present invention is simple and does not require a large number of tests, thus saving experimental costs;

[0061] The present invention performs PID control on the driving force error, so that the unmanned mining truck does not slip when starting, and the safety is guaranteed. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] In order to make the content of the present invention more clearly understood, the present invention is further described in detail below based on specific embodiments and in conjunction with the accompanying drawings, wherein:

[0063] Figure 1 This is a structural diagram of an unmanned mining truck anti-skid when starting according to an embodiment of the present invention;

[0064] Figure 2 This is a schematic diagram of the acceleration statistics module structure of an embodiment of the present invention;

[0065] Figure 3 The present invention is a flow chart of an unmanned mining truck anti-skid control method when starting. DETAILED DESCRIPTION

[0066] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the scope of protection of the present invention.

[0067] The application principle of the present invention is described in detail below in conjunction with the accompanying drawings.

[0068] Example 1

[0069] like Figure 1 As shown, an embodiment of the present invention provides an unmanned mining truck anti-skid system when starting, including a starting acceleration statistics module and a starting anti-skid control module;

[0070] The starting acceleration statistics module is used to collect the real-time speed of the unmanned mining truck when starting on a flat road at different expected speeds, calculate the starting acceleration based on the real-time speed, and calculate the corresponding relationship between different expected speeds and starting acceleration, generate a starting acceleration table and send it to the starting anti-slip control module; in the specific implementation process, the expected speed is sent from the decision module to the starting acceleration statistics module; the statistical method of the corresponding relationship between the expected speed and the starting acceleration is: the starting acceleration statistics module collects driving data once every set operation cycle, takes the actual speed of the unmanned mining truck from rest to driving t, and the acceleration calculated by the kinematic formula is the starting acceleration under the expected speed, and a two-dimensional table (starting acceleration table) corresponding to the expected speed and the starting acceleration is made; the calculation formula of the starting acceleration is:

[0071]

[0072] Among them, a is the starting acceleration, Vn is the speed collected at the time of the nth operation cycle of the unmanned mining truck, and T is the operation cycle of the unmanned mining truck.

[0073] The starting anti-skid control module calculates the expected driving force based on the received expected speed, the starting acceleration table, the pitch angle of the unmanned mining truck and the loading weight of the unmanned mining truck, and further obtains the throttle amount or the braking amount, and accumulates the obtained throttle amount or the braking amount with the throttle amount or the braking amount of the previous operation cycle and sends it to the power system of the unmanned mining truck; in the specific implementation process, the expected speed is sent from the decision module to the starting anti-skid control module, and the starting acceleration table is sent from the starting acceleration statistics module to the starting anti-skid control module.

[0074] In a specific implementation of the embodiment of the present invention, Figure 1 As shown, the start-up anti-slip control module includes: a desired acceleration submodule, a driving force error submodule, a driving force control submodule and an accumulation submodule connected in sequence;

[0075] The expected acceleration submodule is used to receive the expected speed sent by the decision module and the starting acceleration table sent by the starting acceleration statistics module, obtain the expected acceleration through a two-dimensional linear interpolation method, and transmit it to the driving force error submodule;

[0076] The driving force error submodule is used to receive the expected acceleration, the pitch angle of the unmanned mining truck and the loading weight of the unmanned mining truck, calculate the expected driving force required by the unmanned mining truck according to the vehicle dynamics model, and compare it with the received actual driving force of the unmanned mining truck to obtain the driving force error; judge whether the driving force error is greater than zero, if so, send the driving force error to the driving force control submodule, if not, send a control instruction to the hydraulic system, the hydraulic system releases the hydraulic brake device, and the unmanned mining truck enters the driving state; specifically, the calculation formula of the driving force error is:

[0077] m=m 车 +m 载

[0078] F g =m·g·sinθ

[0079] F drive =F g +m·a

[0080] F error =F drive -F drive_now

[0081] Among them, m is the total mass of the unmanned mining truck, m 车 is the weight of the unmanned mining truck, m 载 F is the loading weight of the unmanned mining truck. drive is the expected driving force, F g is the component of gravity on the ramp, g is the acceleration of gravity, θ is the pitch angle of the unmanned mining truck, a is the starting acceleration, and F error is the driving force error, F drive_now The actual driving force of the unmanned mining truck uploaded by the mining truck’s main power system.

[0082] The driving force control submodule is used to receive the driving force error sent by the driving force error submodule, obtain the throttle amount or the braking amount through the PID controller, and send it to the accumulation submodule; the driving force error sent by the driving force error submodule is received, and the throttle amount or the braking amount is obtained through the PID controller. The specific process is:

[0083]

[0084] Among them, U n is the throttle amount or brake amount calculated in the nth cycle, K P is the proportionality coefficient, KI is the integration coefficient, K D is the differential coefficient, F error (t) is the driving force error of the nth cycle, t = n·T, T is the operation cycle of the unmanned mining truck.

[0085] The accumulation submodule is used to receive the throttle amount or brake amount sent by the driving force control submodule, accumulate the throttle amount or brake amount with the throttle amount or brake amount of the previous operation cycle to obtain the final throttle amount or brake amount, and send it to the power system of the unmanned mining truck; the calculation formula of the final throttle amount or brake amount is:

[0086] U total =U 1 +U 2 +…+U n

[0087] Among them, U total Calculate the accumulated value of the throttle amount or the brake amount for n operating cycles.

[0088] The unmanned mining truck anti-skid system when starting in the embodiment of the present invention is described in detail below in conjunction with a specific implementation.

[0089] Take the start of an unmanned mining truck in an open-pit mine as an example. The unmanned mining truck body includes a power system, a hydraulic system, a weighing system and an inertial navigation system. The power system includes the engine, generator, inverter, discharge resistor, wheel-side motor, throttle, electric brake and hydraulic brake device of the mining truck. The wheel-side motor collects the actual driving force and transmits it to the driving force error submodule. The hydraulic system is connected to the hydraulic brake device to control the low-speed braking and parking of the unmanned mining truck. The gear adopts the automatic gear mode. The inertial navigation system adopts the form of an inertial navigation plus radio combination, which can accurately provide information such as the real-time speed and pitch angle of the unmanned mining truck. The weighing system installs multiple weighing sensors between the carriage and the frame, measures the weight of the carriage, obtains the loading weight of the unmanned mining truck, and transmits it to the driving force error submodule after processing.

[0090] The unmanned mining truck anti-skid system at the start in the embodiment of the present invention comprises: a start acceleration statistics module and a start anti-skid control module;

[0091] The decision-making module sends the expected speed and expected gear to the starting anti-slip control module according to the road conditions and work requirements.

[0092] The starting speed characteristics of the unmanned mining truck in the longitudinal control state are collected and counted. For details, see Figure 2. On the flat section of the transport route, release the hydraulic brake device and start at the expected speeds of 5km / h, 10km / h, 15km / h, 20km / h, 25km / h, 30km / h, 35km / h and 40km / h respectively. The decision module is used to issue the expected speed of 5km / h, and the longitudinal control module is used to control the throttle connected to it to drive in a straight line. The starting acceleration statistics module collects driving data once every 0.1s operation cycle, and takes the actual speed of the unmanned mining truck from rest to driving for 1s. The acceleration calculated by the kinematic formula is the starting acceleration at the expected speed. According to the aforementioned starting acceleration calculation process, the starting acceleration at other expected speeds is calculated, and a two-dimensional table (starting acceleration table) corresponding to the expected speed and starting acceleration is made.

[0093] When the unmanned mining truck needs to start on a slope, the decision module is used to send the expected speed and expected gear position. The expected acceleration submodule queries the starting acceleration table according to the expected speed and uses two-dimensional linear interpolation to obtain the expected acceleration. The driving force error submodule calculates the resultant external force according to the expected acceleration (i.e., starting acceleration) and the total weight of the unmanned mining truck. The resultant external force refers to the sum of all external forces acting on an object. The total weight of the unmanned mining truck refers to the sum of the weight of the unmanned mining truck body and the weight of the unmanned mining truck load; the sliding force (i.e., the component of gravity on the slope) is calculated based on the collected pitch angle of the unmanned mining truck and the weight of the unmanned mining truck load, and the expected gear position is used to determine whether to move forward or backward. The driving force error is finally calculated based on the actual driving force collected. The calculation formula for the expected driving force is:

[0094] m=m 车 +m 载

[0095] F g =m·g·sinθ

[0096] F drive =F g +m·a

[0097] Among them, F drive is the expected driving force, m is the total mass of the unmanned mining truck, and m 车 is the weight of the unmanned mining truck, m 载 is the loading weight of the unmanned mining truck, g is the acceleration of gravity, θ is the pitch angle of the unmanned mining truck, a is the starting acceleration, F g is the component of gravity on the ramp, m·a represents the resultant external force;

[0098] The calculation formula of the driving force error is:

[0099] F error =F drive -F drive_now

[0100] Among them, F error is the driving force error, F drive_now The actual driving force of the unmanned mining truck uploaded by the mining truck’s main power system.

[0101] The driving force control submodule calculates the output throttle or brake amount through the PID controller according to the driving force error. The accumulation submodule accumulates the throttle or brake amount calculated in the previous operation cycle and sends it to the unmanned mining truck main power system. When the driving force error is zero, the driving force error submodule sends a control instruction to the hydraulic system, the hydraulic system releases the hydraulic brake device, and the unmanned mining truck enters the driving state. The calculation formula of the throttle or brake amount is:

[0102]

[0103] Among them, U n is the throttle amount or brake amount calculated in the nth cycle, K P is the proportionality coefficient, K I is the integration coefficient, K D is the differential coefficient, Ferror(t) is the driving force error of the nth cycle, t = n·T, T is the operation cycle of the unmanned mining truck;

[0104] The calculation formula of the final throttle amount or brake amount is:

[0105] U total =U 1 +U 2 +…+U n

[0106] Among them, U total Calculate the accumulated value of the throttle amount or the brake amount for n operating cycles.

[0107] The working process of the unmanned mining truck anti-skid system in the embodiment of the present invention is as follows:

[0108] S1. Release the hydraulic brake device on a flat road and collect the actual speed of the unmanned mining truck when starting at different expected speeds.

[0109] S2, counting the actual speed v of the unmanned mining truck from rest to driving t, calculating the starting acceleration, and making a starting acceleration table corresponding to the expected speed;

[0110] S3, when the unmanned mining truck enters the starting state, the expected acceleration is obtained by looking up the expected speed and starting acceleration table.

[0111] S4. According to the expected acceleration, the expected gear position, the pitch angle of the unmanned mining truck and the loading weight of the unmanned mining truck, the expected driving force required by the unmanned mining truck is calculated through the vehicle dynamics model, and the driving force error is obtained by comparing with the actual driving force, and it is determined whether the driving force error is greater than zero. If so, execute step S5, if not, execute step S6.

[0112] S5. According to the calculated driving force error, the PID controller calculates the throttle amount or the braking amount and adds it with the previous cycle and sends it to the power system of the mining truck body, and then continues to execute the step S4.

[0113] S6. Send a control command to the hydraulic system, the hydraulic system releases the hydraulic brake device, and the unmanned mining truck enters the driving state.

[0114] When the unmanned mining truck enters the driving state, a longitudinal control module connected to the power system of the mining truck body is used. The longitudinal control module stores a speed control algorithm based on the motor characteristics. When starting, the anti-skid system controls the throttle. When driving, the longitudinal control module controls the throttle and brakes to enter the driving state. During specific use, the longitudinal control module calculates the throttle amount or brake amount based on the expected speed and expected gear received from the decision module, and sends the throttle amount or brake amount to the power system of the unmanned mining truck to control the driving speed of the unmanned mining truck.

[0115] Example 2

[0116] The embodiment of the present invention provides a control method for an unmanned mining truck anti-skid system when starting, comprising the following steps:

[0117] The starting acceleration statistics module is used to collect the real-time speed of the unmanned mining truck on a flat road when starting at different expected speeds, the starting acceleration is calculated based on the real-time speed, and the corresponding relationship between different expected speeds and the starting acceleration is statistically calculated. After generating a starting acceleration table, it is sent to the starting anti-slip control module; in the specific implementation process, the expected speed is sent from the decision module to the starting acceleration statistics module; the statistical method of the corresponding relationship between the expected speed and the starting acceleration is: the starting acceleration statistics module collects driving data once every set operation cycle, takes the actual speed of the unmanned mining truck from rest to driving t, and the acceleration calculated by the kinematic formula is the starting acceleration under the expected speed, and a two-dimensional table (starting acceleration table) corresponding to the expected speed and the starting acceleration is made; the calculation formula of the starting acceleration is:

[0118]

[0119] Among them, a is the starting acceleration, Vn is the speed collected at the time of the nth operation cycle of the unmanned mining truck, and T is the operation cycle of the unmanned mining truck.

[0120] The starting anti-skid control module calculates the expected driving force based on the received expected speed, starting acceleration table, pitch angle and loading weight of the unmanned mining truck, and further obtains the throttle amount or braking amount. The obtained throttle amount or braking amount is added to the throttle amount or braking amount of the previous operation cycle and sent to the power system of the unmanned mining truck.

[0121] In a specific implementation of the embodiment of the present invention, Figure 1 As shown, the start-up anti-slip control module includes: a desired acceleration submodule, a driving force error submodule, a driving force control submodule and an accumulation submodule connected in sequence;

[0122] The expected acceleration submodule is used to receive the expected speed sent by the decision module and the starting acceleration table sent by the starting acceleration statistics module, obtain the expected acceleration through a two-dimensional linear interpolation method, and transmit it to the driving force error submodule;

[0123] The driving force error submodule is used to receive the expected acceleration, the pitch angle of the unmanned mining truck and the loading weight of the unmanned mining truck, calculate the expected driving force required by the unmanned mining truck according to the vehicle dynamics model, and compare it with the received actual driving force of the unmanned mining truck to obtain the driving force error. It is judged whether the driving force error is greater than zero. If so, the driving force error is sent to the driving force control submodule. If not, a control instruction is sent to the hydraulic system, and the hydraulic system releases the hydraulic brake device, and the unmanned mining truck enters the driving state;

[0124] Specifically, the calculation formula of the driving force error is:

[0125] m=m 车 +m 载

[0126] F g =m·g·sinθ

[0127] F drive =F g +m·a

[0128] F error =F drive -F drive_now

[0129] Among them, m is the total mass of the unmanned mining truck, m 车 is the weight of the unmanned mining truck, m 载 F is the loading weight of the unmanned mining truck. drive is the expected driving force, F g is the component of gravity on the ramp, g is the acceleration of gravity, θ is the pitch angle of the unmanned mining truck, a is the starting acceleration, and F error is the driving force error, Fdrive_now The actual driving force of the unmanned mining truck uploaded by the mining truck’s main power system.

[0130] The driving force control submodule is used to receive the driving force error sent by the driving force error submodule, obtain the throttle amount or the braking amount through the PID controller, and send it to the accumulation submodule; the driving force error sent by the driving force error submodule is received, and the throttle amount or the braking amount is obtained through the PID controller. The specific process is:

[0131]

[0132] Among them, U n is the throttle amount or brake amount calculated in the nth cycle, K P is the proportionality coefficient, K I is the integration coefficient, K D is the differential coefficient, F error (t) is the driving force error of the nth cycle, t = n·T, T is the operation cycle of the unmanned mining truck.

[0133] The accumulation submodule is used to receive the throttle amount or brake amount sent by the driving force control submodule, accumulate the throttle amount or brake amount with the throttle amount or brake amount of the previous operation cycle to obtain the final throttle amount or brake amount, and send it to the power system of the unmanned mining truck; the calculation formula of the final throttle amount or brake amount is:

[0134] U total =U 1 +U 2 +…+U n

[0135] Among them, U total Calculate the accumulated value of the throttle amount or the brake amount for n operating cycles.

[0136] The unmanned mining truck anti-skid system when starting in the embodiment of the present invention is described in detail below in conjunction with a specific implementation.

[0137] Take the start of an unmanned mining truck in an open-pit mine as an example. The unmanned mining truck body includes a power system, a hydraulic system, a weighing system and an inertial navigation system. The power system includes the engine, generator, inverter, discharge resistor, wheel-side motor, throttle, electric brake and hydraulic brake device of the mining truck. The wheel-side motor collects the actual driving force and transmits it to the driving force error submodule. The hydraulic system is connected to the hydraulic brake device to control the low-speed braking and parking of the unmanned mining truck. The gear adopts the automatic gear mode. The inertial navigation system adopts the form of an inertial navigation plus radio combination, which can accurately provide information such as the real-time speed and pitch angle of the unmanned mining truck. The weighing system installs multiple weighing sensors between the carriage and the frame, measures the weight of the carriage, obtains the loading weight of the unmanned mining truck, and transmits it to the driving force error submodule after processing.

[0138] The unmanned mining truck anti-skid system at the start in the embodiment of the present invention comprises: a start acceleration statistics module and a start anti-skid control module;

[0139] The decision-making module sends the expected speed and expected gear to the starting anti-slip control module according to the road conditions and work requirements.

[0140] The starting speed characteristics of the unmanned mining truck in the longitudinal control state are collected and counted. For details, see Figure 2 . On the flat section of the transport route, release the hydraulic brake device and start at the expected speeds of 5km / h, 10km / h, 15km / h, 20km / h, 25km / h, 30km / h, 35km / h and 40km / h respectively. The decision module is used to issue the expected speed of 5km / h, and the longitudinal control module is used to control the throttle connected to it to drive in a straight line. The starting acceleration statistics module collects driving data once every 0.1s operation cycle, and takes the actual speed of the unmanned mining truck from rest to driving for 1s. The acceleration calculated by the kinematic formula is the starting acceleration at the expected speed. According to the aforementioned starting acceleration calculation process, the starting acceleration at other expected speeds is calculated, and a two-dimensional table (starting acceleration table) corresponding to the expected speed and starting acceleration is made.

[0141] When the unmanned mining truck needs to start on a slope, the decision module is used to send the expected speed and expected gear position. The expected acceleration submodule queries the starting acceleration table according to the expected speed and uses two-dimensional linear interpolation to obtain the expected acceleration. The driving force error submodule calculates the resultant external force according to the expected acceleration (i.e., starting acceleration) and the total weight of the unmanned mining truck. The resultant external force refers to the sum of all external forces acting on an object. The total weight of the unmanned mining truck refers to the sum of the weight of the unmanned mining truck body and the weight of the unmanned mining truck load; the sliding force (i.e., the component of gravity on the slope) is calculated based on the collected pitch angle of the unmanned mining truck and the weight of the unmanned mining truck load, and the expected gear position is used to determine whether to move forward or backward. The driving force error is finally calculated based on the actual driving force collected. The calculation formula for the expected driving force is:

[0142] m=m 车 +m 载

[0143] F g =m·g·sinθ

[0144] F drive =F g +m·a

[0145] Among them, F drive is the expected driving force, m is the total mass of the unmanned mining truck, and m 车 is the weight of the unmanned mining truck, m载 is the loading weight of the unmanned mining truck, g is the acceleration of gravity, θ is the pitch angle of the unmanned mining truck, a is the starting acceleration, F g is the component of gravity on the ramp, m·a represents the resultant external force;

[0146] The calculation formula of the driving force error is:

[0147] F error =F drive -F drive_now

[0148] Among them, F error is the driving force error, F drive_now The actual driving force of the unmanned mining truck uploaded by the mining truck’s main power system.

[0149] The driving force control submodule calculates the output throttle or brake amount through the PID controller according to the driving force error. The accumulation submodule accumulates the throttle or brake amount calculated in the previous operation cycle and sends it to the unmanned mining truck main power system. When the driving force error is zero, the driving force error submodule sends a control instruction to the hydraulic system, the hydraulic system releases the hydraulic brake device, and the unmanned mining truck enters the driving state. The calculation formula of the throttle or brake amount is:

[0150]

[0151] Among them, U n is the throttle amount or brake amount calculated in the nth cycle, K P is the proportionality coefficient, K I is the integration coefficient, K D is the differential coefficient, F error (t) is the driving force error of the nth cycle, t = n·T, T is the operation cycle of the unmanned mining truck;

[0152] The calculation formula of the final throttle amount or brake amount is:

[0153] U total =U 1 +U 2 +…+U n

[0154] Among them, U total Calculate the accumulated value of the throttle amount or the brake amount for n operating cycles.

[0155] The working process of the unmanned mining truck anti-skid system in the embodiment of the present invention is as follows:

[0156] S1. Release the hydraulic brake device on a flat road and collect the actual speed of the unmanned mining truck when starting at different expected speeds.

[0157] S2, counting the actual speed v of the unmanned mining truck from rest to driving t, calculating the starting acceleration, and making a starting acceleration table corresponding to the expected speed;

[0158] S3, when the unmanned mining truck enters the starting state, the expected acceleration is obtained by looking up the expected speed and starting acceleration table.

[0159] S4. According to the expected acceleration, the expected gear position, the pitch angle of the unmanned mining truck and the loading weight of the unmanned mining truck, the expected driving force required by the unmanned mining truck is calculated through the vehicle dynamics model, and the driving force error is obtained by comparing with the actual driving force, and it is determined whether the driving force error is greater than zero. If so, execute step S5, if not, execute step S6.

[0160] S5. According to the calculated driving force error, the PID controller calculates the throttle amount or the braking amount and adds it with the previous cycle and sends it to the power system of the mining truck body, and then continues to execute the step S4.

[0161] S6. Send a control command to the hydraulic system, the hydraulic system releases the hydraulic brake device, and the unmanned mining truck enters the driving state.

[0162] When the unmanned mining truck enters the driving state, a longitudinal control module connected to the power system of the mining truck body is used. The longitudinal control module stores a speed control algorithm based on the motor characteristics. When starting, the anti-skid system controls the throttle. When driving, the longitudinal control module controls the throttle and brakes to enter the driving state. During specific use, the longitudinal control module calculates the throttle amount or brake amount based on the expected speed and expected gear received from the decision module, and sends the throttle amount or brake amount to the power system of the unmanned mining truck to control the driving speed of the unmanned mining truck.

[0163] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. An unmanned mining truck anti-skid system, characterized in that: include: Starting acceleration statistics module and starting anti-slip control module; The starting acceleration statistics module is used to collect the real-time speed of the unmanned mining truck when starting at different expected speeds, calculate the starting acceleration based on the real-time speed, and calculate the corresponding relationship between different expected speeds and starting acceleration, generate a starting acceleration table and send it to the starting anti-slip control module; The starting anti-slip control module calculates the expected driving force based on the received expected speed, the starting acceleration table, the pitch angle of the unmanned mining truck and the unmanned mining truck load weight, and further obtains the throttle amount or the braking amount, and accumulates the obtained throttle amount or the braking amount with the throttle amount or the braking amount of the previous operation cycle and sends the accumulated amount to the power system of the unmanned mining truck; The start-up anti-slip control module includes: a desired acceleration submodule, a driving force error submodule, a driving force control submodule and an accumulation submodule connected in sequence; The expected acceleration submodule is used to receive the expected speed sent by the decision module and the starting acceleration table sent by the starting acceleration statistics module, obtain the expected acceleration through a two-dimensional linear interpolation method, and transmit it to the driving force error submodule; The driving force error submodule is used to receive the expected acceleration, the pitch angle of the unmanned mining truck and the loading weight of the unmanned mining truck, calculate the expected driving force required by the unmanned mining truck according to the vehicle dynamics model, and compare it with the received actual driving force of the unmanned mining truck to obtain the driving force error; judge whether the driving force error is greater than zero, if so, send the driving force error to the driving force control submodule, if not, send a control instruction to the hydraulic system, the hydraulic system releases the hydraulic brake device, and the unmanned mining truck enters the driving state; The driving force control submodule is used to receive the driving force error sent by the driving force error submodule, obtain the throttle amount or the braking amount through the PID controller, and send it to the accumulation submodule; The accumulation submodule is used to receive the throttle amount or brake amount sent by the driving force control submodule, accumulate the throttle amount or brake amount with the throttle amount or brake amount of the previous operation cycle to obtain the final throttle amount or brake amount, and send it to the power system of the unmanned mining truck.

2. The unmanned mining truck anti-skid system when starting according to claim 1, characterized in that: The calculation formula of the starting acceleration is: Where a is the starting acceleration, V n It is the speed collected when the unmanned mining truck starts the nth operation cycle, and T is the operation cycle of the unmanned mining truck.

3. The unmanned mining truck anti-skid system when starting according to claim 1, characterized in that: The statistical method for the corresponding relationship between the expected speed and the starting acceleration is: The starting acceleration statistics module collects driving data once every set operating cycle, takes the actual speed of the unmanned mining truck from rest to driving t, and the acceleration calculated by the kinematic formula is the starting acceleration at the expected speed.

4. The unmanned mining truck anti-skid system when starting according to claim 1, characterized in that: The calculation formula of the driving force error is: m=m 车 +m 载 F g =m·g·sinθ F drive =F g +m·a F error =F drive -F drive_now Among them, m is the total mass of the unmanned mining truck, m 车 is the weight of the unmanned mining truck, m 载 F is the loading weight of the unmanned mining truck. drive is the expected driving force, F g is the component of gravity on the ramp, g is the acceleration of gravity, θ is the pitch angle of the unmanned mining truck, a is the starting acceleration, and F error is the driving force error, F drive_now The actual driving force of the unmanned mining truck uploaded by the mining truck’s main power system.

5. The unmanned mining truck anti-skid system when starting according to claim 1, characterized in that: The driving force error sent by the receiving driving force error submodule is used to obtain the throttle amount or the braking amount through the PID controller. The calculation formula of the throttle amount or the braking amount is: Among them, U n is the throttle amount or brake amount calculated in the nth cycle, K P is the proportionality coefficient, K I is the integration coefficient, K D is the differential coefficient, F error (t) is the driving force error of the nth cycle, t = nT, T is the operation cycle of the unmanned mining truck; The calculation formula of the final throttle amount or brake amount is: U total =U1+U2+…+U n Among them, U total Calculate the accumulated value of the throttle amount or the brake amount for n operating cycles.

6. A control method for an unmanned mining truck anti-skid system when starting, characterized in that: include: The starting acceleration statistics module is used to collect the real-time speed of the unmanned mining truck when starting at different expected speeds on a flat road, the starting acceleration is calculated based on the real-time speed, and the corresponding relationship between different expected speeds and starting acceleration is statistically calculated. After generating a starting acceleration table, it is sent to the starting anti-slip control module; The starting anti-slip control module is used to calculate the expected driving force based on the received expected speed, the starting acceleration table, the pitch angle of the unmanned mining truck, and the unmanned mining truck loading weight, and further obtain the throttle amount or braking amount, and the obtained throttle amount or braking amount is accumulated with the throttle amount or braking amount of the previous operation cycle and sent to the power system of the unmanned mining truck; The start-up anti-slip control module includes: a desired acceleration submodule, a driving force error submodule, a driving force control submodule and an accumulation submodule connected in sequence; The expected acceleration submodule is used to receive the expected speed sent by the decision module and the starting acceleration table sent by the starting acceleration statistics module, obtain the expected acceleration through a two-dimensional linear interpolation method, and transmit it to the driving force error submodule; The driving force error submodule is used to receive the expected acceleration, the pitch angle of the unmanned mining truck and the loading weight of the unmanned mining truck, calculate the expected driving force required by the unmanned mining truck according to the vehicle dynamics model, and compare it with the received actual driving force of the unmanned mining truck to obtain the driving force error; judge whether the driving force error is greater than zero, if so, send the driving force error to the driving force control submodule, if not, send a control instruction to the hydraulic system, the hydraulic system releases the hydraulic brake device, and the unmanned mining truck enters the driving state; The driving force control submodule is used to receive the driving force error sent by the driving force error submodule, obtain the throttle amount or the braking amount through the PID controller, and send it to the accumulation submodule; The accumulation submodule is used to receive the throttle amount or brake amount sent by the driving force control submodule, accumulate the throttle amount or brake amount with the throttle amount or brake amount of the previous operation cycle to obtain the final throttle amount or brake amount, and send it to the power system of the unmanned mining truck.

7. The control method of the unmanned mining truck anti-skid system when starting according to claim 6 is characterized in that: The calculation formula of the starting acceleration is: Among them, a is the starting acceleration, Vn is the speed collected at the start of the nth operating cycle of the unmanned mining truck, and T is the operating cycle of the unmanned mining truck.

8. The control method of the unmanned mining truck anti-skid system when starting according to claim 6 is characterized in that: The statistical method for the corresponding relationship between the expected speed and the starting acceleration is: The starting acceleration statistics module collects driving data once every set operating cycle, takes the actual speed of the unmanned mining truck from rest to driving t, and the acceleration calculated by the kinematic formula is the starting acceleration at the expected speed.

9. The control method of the unmanned mining truck anti-skid system when starting according to claim 6, characterized in that: The calculation formula of the driving force error is: m=m 车 +m 载 F g =m·g·sinθ F drive =F g +m·a F error =F drive -F drive_now Among them, m is the total mass of the unmanned mining truck, m 车 is the weight of the unmanned mining truck, m 载 F is the loading weight of the unmanned mining truck. drive is the expected driving force, F g is the component of gravity on the ramp, g is the acceleration of gravity, θ is the pitch angle of the unmanned mining truck, a is the starting acceleration, and F error is the driving force error, F drive_now The actual driving force of the unmanned mining truck uploaded by the mining truck’s main power system.

10. The control method of the unmanned mining truck anti-skid system when starting according to claim 6, characterized in that: The driving force error sent by the receiving driving force error submodule is used to obtain the throttle amount or the braking amount through the PID controller. The calculation formula of the throttle amount or the braking amount is: Among them, U n is the throttle amount or brake amount calculated in the nth cycle, K P is the proportionality coefficient, K I is the integration coefficient, K D is the differential coefficient, Ferror(t) is the driving force error of the nth cycle, t=nT, T is the operation cycle of the unmanned mining truck; The calculation formula of the final throttle amount or brake amount is: U total =U1+U2+…+U n Among them, U total Calculate the accumulated value of the throttle amount or the brake amount for n operating cycles.

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