Economic torque determination method and apparatus in expressway slope scenario, and medium

Abstract

The present invention belongs to the technical field of vehicle control and relates to an economic torque determination method and apparatus in an expressway slope scenario, and a medium. The method comprises: on the basis of road types corresponding to slope segments, merging the slope segments, and determining an integrated slope after merging, wherein the slope segments are obtained by means of slicing the road ahead of a vehicle; on the basis of the gradient and length of the integrated slope, determining the acceleration of the vehicle; and on the basis of the acceleration, determining an economic torque. By means of the economic torque determination method in an expressway slope scenario provided in the present invention, a complete integrated slope is accurately identified in a complex slope environment; on the basis of the gradient and length of the integrated slope, the acceleration of a vehicle in the integrated slope is calculated; and then on the basis of the acceleration and a vehicle dynamics equation, a required economic torque is calculated. The economic torque is the torque required by the vehicle to maintain the optimal fuel economy on the slope. Thus, the travelling requirements are met and the fuel efficiency is also improved.

Description

Methods, devices, and media for determining economic torque in highway slope scenarios Technical Field

[0001] This invention relates to the field of vehicle control technology, and in particular to a method, device and medium for determining economic torque in a high-speed road slope scenario. Background Technology

[0002] Vehicle fuel efficiency is an important indicator used to measure the extent to which a vehicle can save fuel during operation. Different types of vehicles and different technologies can achieve different levels of fuel efficiency.

[0003] Existing methods propose a slope cruise speed control approach based on high-precision maps. By setting a trigger speed adjustment distance, the vehicle speed is controlled based on a speed adjustment threshold and slope using a lookup table when the distance is reached, maximizing fuel efficiency. However, this method relies on information from high-precision maps for economical cruise speed planning on slopes. The distance of the road information provided by high-precision maps is insufficient, making comprehensive planning impossible in complex slope environments such as those with significant gradient changes or extremely long inclines. Summary of the Invention

[0004] In view of this, it is necessary to provide a method, device and medium for determining economic torque in high-speed road slope scenarios, so as to realize the planning of vehicle economic torque in complex slope environments.

[0005] To achieve the above objectives, the present invention provides a method for determining economic torque in a highway ramp scenario, comprising:

[0006] The ramp slices are merged based on the road type corresponding to the ramp slices to determine the merged ramp; the ramp slices are obtained by slicing the road in front of the vehicle.

[0007] The vehicle's acceleration is determined based on the slope and length of the fusion ramp.

[0008] Based on the acceleration, the economic torque is determined.

[0009] In one possible implementation, merging the ramp slices based on the road type corresponding to the ramp slices to determine the merged integrated ramp includes:

[0010] Traverse the ramp slices, and when it is determined that the road type of the current ramp slice is uphill, determine the sequence number of the current ramp slice as the starting sequence number;

[0011] Based on the starting number, the slope slices are traversed. When it is determined that the road type of the next slope slice is uphill, the next slope slice is merged with the current slope slice, and the number of the next slope slice is determined as the end number.

[0012] The traversal stops when the road type of the next slope slice is either downhill or flat, and the merged slope is obtained.

[0013] In one possible implementation, before determining the vehicle's acceleration based on the slope and length of the fused ramp, the method further includes:

[0014] Based on the start number and the end number, the slope and length of the fusion ramp are determined.

[0015] In one possible implementation, determining the vehicle's acceleration based on the slope and length of the fused ramp includes:

[0016] The preset slope is divided into segments to obtain multiple slope values;

[0017] The preset slope length is divided into segments to obtain multiple slope length values;

[0018] Each slope value is associated with a different slope length value, and the corresponding acceleration value is determined through a simulation model; the simulation model is a vehicle dynamics model built based on Trucksim and MATLAB.

[0019] An acceleration table is constructed based on the correspondence between the slope value, the slope length value, and the acceleration value;

[0020] The vehicle's acceleration is determined in the acceleration table based on the slope and length of the fusion ramp.

[0021] In one possible implementation, determining the economic torque based on the acceleration includes:

[0022] Based on the acceleration, determine the acceleration resistance;

[0023] The driving force is determined based on the vehicle's rolling resistance, air resistance, gradient resistance, and acceleration resistance.

[0024] The economic torque is determined based on the driving force.

[0025] In one possible implementation, the economic torque is expressed as follows:

[0026] Where T represents economic torque, F tη1 represents the driving force, r represents the wheel radius, η2 represents the gear ratio, η3 represents the final drive ratio, and η3 represents the transmission efficiency.

[0027] The present invention also provides an economic torque determination device for highway ramp scenarios, comprising:

[0028] The merging module is used to merge the ramp slices based on the road type corresponding to the ramp slices, and determine the merged and integrated ramp; the ramp slices are obtained by slicing the road in front of the vehicle.

[0029] The first determining module is used to determine the vehicle's acceleration based on the slope and length of the fusion ramp;

[0030] The second determining module is used to determine the economic torque based on the acceleration.

[0031] On the other hand, the present invention also provides an electronic device, including a memory and a processor, wherein,

[0032] The memory is used to store programs;

[0033] The processor, coupled to the memory, is used to execute the program stored in the memory to implement the method for determining economic torque in a high-speed road slope scenario as described in any of the above implementations.

[0034] On the other hand, the present invention also provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the method for determining economic torque in a high-speed road slope scenario as described in any of the above implementations.

[0035] On the other hand, the present invention also provides a computer program product, including a computer program that, when executed by a processor, implements the method for determining economic torque in a high-speed road slope scenario as described in any of the above implementations.

[0036] The beneficial effects of this invention are as follows: The method, device, and medium for determining economic torque in highway slope scenarios provided by this invention obtain slope slices by slicing the road in front of the vehicle, and merge the slope slices according to the road type corresponding to the slope slices to obtain a continuous and complete fused slope. This enables accurate identification of the complete fused slope in complex slope environments. Based on the slope and length of the fused slope, the acceleration of the vehicle under the fused slope conditions is calculated. Then, based on the acceleration and vehicle dynamics equations, the required economic torque is calculated. The economic torque is the torque required for the vehicle to maintain optimal fuel economy on the slope. This not only meets driving needs but also improves fuel efficiency. Thus, autonomous vehicles can accurately cope with complex slope conditions on highways to optimize vehicle performance and fuel economy, improving driving efficiency and contributing to a more environmentally friendly driving experience. Attached Figure Description

[0037] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0038] Figure 1 is a flowchart of one embodiment of the method for determining economic torque in a highway slope scenario provided by the present invention.

[0039] Figure 2 is a schematic diagram of ramp slice merging provided by the present invention;

[0040] Figure 3 is a schematic diagram of the co-simulation provided by the present invention;

[0041] Figure 4 is a second method flowchart of an embodiment of the method for determining economic torque in a highway slope scenario provided by the present invention.

[0042] Figure 5 is a schematic diagram of an embodiment of the economic torque determination device for a highway slope scenario provided by the present invention.

[0043] Figure 6 is a schematic diagram of an embodiment of the electronic device provided by the present invention. Detailed Implementation

[0044] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0045] In the description of the embodiments of the present invention, unless otherwise stated, "multiple" means two or more. "And / or" describes the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can represent three situations: A exists alone, A and B exist simultaneously, and B exists alone.

[0046] The terms "first," "second," etc., used in the embodiments of this invention are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a technical feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature.

[0047] Figure 1 is a flowchart of an embodiment of the method for determining economic torque in a highway slope scenario provided by the present invention. As shown in Figure 1, the method for determining economic torque in a highway slope scenario includes:

[0048] S101. Merge the ramp slices based on the road type corresponding to the ramp slices to determine the merged ramp; the ramp slices are obtained by slicing the road in front of the vehicle.

[0049] S102. Determine the vehicle's acceleration based on the slope and length of the fusion ramp;

[0050] S103. Based on the acceleration, determine the economic torque.

[0051] It should be noted that, based on the road map information provided by Tbox, the road in front of the vehicle can be sliced ​​to obtain several ramp slices. Each ramp slice represents a section of road with a certain slope and length. The road type of the ramp slice can be determined based on its slope, and the road type can include uphill, downhill, and flat road types.

[0052] Compared with existing technologies, the method for determining economic torque in highway slope scenarios provided by this invention slices the road in front of the vehicle to obtain slope slices, and merges the slope slices according to the road type corresponding to the slope slices to obtain a continuous and complete merged slope. This enables accurate identification of the complete merged slope in complex slope environments. Based on the slope and length of the merged slope, the acceleration of the vehicle under the merged slope conditions is calculated. Then, based on the acceleration and vehicle dynamics equations, the required economic torque is calculated. The economic torque is the torque required for the vehicle to maintain optimal fuel economy on the slope. This not only meets driving needs but also improves fuel efficiency. Thus, autonomous vehicles can accurately cope with complex slope conditions on highways to optimize vehicle performance and fuel economy, improving driving efficiency and contributing to a more environmentally friendly driving experience.

[0053] In some embodiments of the present invention, merging the ramp slices based on the road type corresponding to the ramp slices to determine the merged fused ramp includes:

[0054] Traverse the ramp slices, and when it is determined that the road type of the current ramp slice is uphill, determine the sequence number of the current ramp slice as the starting sequence number;

[0055] Based on the starting number, the slope slices are traversed. When it is determined that the road type of the next slope slice is uphill, the next slope slice is merged with the current slope slice, and the number of the next slope slice is determined as the end number.

[0056] The traversal stops when the road type of the next slope slice is either downhill or flat, and the merged slope is obtained.

[0057] For example, the slope node data can be initialized and classified based on the road map information provided by Tbox, and sliced ​​and initially merged according to the differences in slope types.

[0058] Traverse all ramp slices of the road ahead and identify the road type for each ramp slice:

[0059] If the road type of the current ramp slice is invalid, an error is returned and an error message is output to the console;

[0060] If the current slope slice is a flat road or a downhill road, skip to the next one.

[0061] If the current slope slice's road type is uphill, record the current slice's index as the starting index, and continue traversing backward from the starting index to identify the road type of each slice:

[0062] If the road type of the next slope slice is not downhill or flat, then the next slope slice is added to the previous slope slice, and the end sequence number is updated to the sequence number of the next slope slice.

[0063] If the road type of the next slope slice is flat or downhill, then the traversal ends.

[0064] This allows us to obtain one or more consecutive road slices, which can be considered as a complete uphill slope, i.e., a merged ramp. Figure 2 is a schematic diagram of ramp slice merging provided by the present invention, and the merged ramp is shown in Figure 2. Furthermore, the initial sequence number, end sequence number, and total length of this uphill slope are known.

[0065] In some embodiments of the present invention, before determining the vehicle acceleration based on the slope and length of the fused ramp, the method further includes:

[0066] Based on the start number and the end number, the slope and length of the fusion ramp are determined.

[0067] A merged ramp is composed of one or more consecutive road segments. The slope length of the merged ramp is obtained by summing the slope lengths of each road segment according to the initial and end numbers of the road segments.

[0068] The slope of the fusion ramp is determined based on its initial and final serial numbers. The calculation process is as follows:

[0069] If the initial sequence number is zero and equal to the end sequence number, meaning the current merged ramp consists of a single slice and is the first segment, it indicates that the vehicle is going uphill. In this case, the slope of the merged ramp is the slope of the current slice.

[0070] If the initial sequence number is zero and the initial sequence number is not equal to the end sequence number, that is, the current fusion ramp consists of multiple slices and starts from the first segment, it means that the vehicle is going uphill. At this time, the slope of the fusion ramp is the weighted average slope of all slices (calculated and accumulated for each slice in the fusion ramp: slope of a single slice * slope length of a single slice / total length of the ramp).

[0071] If the initial sequence number is not zero and the initial sequence number is equal to the end sequence number, that is, the current fusion ramp consists of a single slice and is not the first segment, it means that the fusion ramp is in front of the vehicle. At this time, the slope of the fusion ramp is the slope of the current slice, and the distance between the vehicle and the fusion ramp is the sum of the lengths of all slices before the initial slice.

[0072] If the initial sequence number is not zero and the initial sequence number is not equal to the end sequence number, that is, the current merging ramp consists of multiple slices and does not start from the first segment, it means that the merging ramp is in front of the vehicle. At this time, the slope of the merging ramp is the weighted average slope of all slices (calculated and accumulated for each slice in the merging ramp: slope of a single slice * slope length of a single slice / total length of the ramp). The distance between the vehicle and the merging ramp is the sum of the lengths of all slices before the initial slice.

[0073] The method for determining economic torque in highway slope scenarios provided in this invention embodiment designs a slope fusion method based on slope slices, which can correctly identify complete slopes and perform smoothing processing, facilitating calculation.

[0074] In some embodiments of the present invention, determining the vehicle's acceleration based on the slope and length of the fused ramp includes:

[0075] The preset slope is divided into segments to obtain multiple slope values;

[0076] The preset slope length is divided into segments to obtain multiple slope length values;

[0077] Each slope value is associated with a different slope length value, and the corresponding acceleration value is determined through a simulation model; the simulation model is a vehicle dynamics model built based on Trucksim and MATLAB.

[0078] An acceleration table is constructed based on the correspondence between the slope value, the slope length value, and the acceleration value;

[0079] The vehicle's acceleration is determined in the acceleration table based on the slope and length of the fusion ramp.

[0080] In this embodiment of the invention, a vehicle dynamics model, i.e. a simulation model, can be pre-built using Trucksim and MATLAB. The simulation model can simulate vehicle scenarios under various working conditions. Figure 3 is a schematic diagram of the joint simulation process of the simulation model provided by the present invention.

[0081] The simulation model provided in this embodiment of the invention comprises two parts:

[0082] First, the controlled object model: In order to accurately simulate the real dynamics of the vehicle and accurately calculate the vehicle's fuel consumption, the controlled object model of the algorithm is built in TruckSim using detailed vehicle data.

[0083] Second, a mathematical model of the vehicle's driving process is constructed based on vehicle dynamics to facilitate the derivation of the control law. The controller model is constructed in Simulink.

[0084] In addition, the selection of the bottom speed is based on the recommended speed in the regulations, and combined with the speed range that allows the vehicle's engine to operate in the economic speed range under the current operating conditions, the final economic cruising speed is taken as the bottom speed.

[0085] The speed at the crest of a hill is categorized into two cases: If no gear shifting is required, the speed at the crest of a hill should be set to the lowest speed the vehicle can maintain without shifting, i.e., the lowest speed the vehicle can achieve in the current gear. If the vehicle must downshift, the speed at the crest of a hill should be set to the speed at the shift point corresponding to the final gear.

[0086] Once the economical slope bottom and slope top velocities are determined, the slope length and slope of the fusion ramp are obtained in the above embodiments, and the corresponding acceleration values ​​can be calculated through the simulation model.

[0087] However, in practical use, it is obviously impractical to call the model for calculation every time. Therefore, the solution of this method is as follows:

[0088] Create a table of discrete data, dividing the preset slope into 6 segments {1,2,3,4,5,6}, resulting in 6 slope values. Divide the preset slope length into 15 segments {200,400,600,800,1000,1200,1400,1600,1800,2000,2200,2400,2600,2800,3000}, resulting in 15 slope length values.

[0089] Each slope value is associated with a different slope length value, resulting in a total of 6*15 sets of corresponding data. The acceleration values ​​for each of the 6*15 cases are calculated using a simulation model. Based on the correspondence between slope value, slope length value, and acceleration value, an acceleration table is constructed.

[0090] For example, the appropriate slope length and slope setting can be selected based on the slope and length of the fusion ramp.

[0091] Since the actual length of a slope is often not exactly equal to the designated slope lengths, it is necessary to select an appropriate gear based on the actual slope length. The strategy is to choose the smallest possible deceleration value to avoid the vehicle losing speed too quickly. If the slope length is less than 200, set it to gear 200; if the slope length is greater than 3000, set it to gear 3000; if it is between the two gears, choose the smaller one.

[0092] Similar to slope length, slope is also mostly not exactly an integer value, so it also needs to be handled. If the slope is greater than 0 and less than 1, select the slope 1 setting, multiply the corresponding deceleration by the slope value, and then multiply by a scaling factor to ensure a smooth transition for small slopes; if the slope is greater than 6%, select the 6 setting; if the slope value is between the two settings, select the smaller setting.

[0093] Therefore, based on the slope and length of the fusion ramp, the corresponding acceleration value can be obtained by looking up the table.

[0094] The method for determining economic torque in a high-speed road slope scenario provided in this invention uses a simulation model built with heavy truck vehicle information to better simulate the dynamic characteristics of the research object. It also proposes a method for determining uphill acceleration, simplifying the acceleration data calculated by the simulation model into a table. The corresponding economic acceleration can be obtained by querying the table in a specified way.

[0095] In some embodiments of the present invention, determining the economic torque based on the acceleration includes:

[0096] Based on the acceleration, determine the acceleration resistance;

[0097] The driving force is determined based on the vehicle's rolling resistance, air resistance, gradient resistance, and acceleration resistance.

[0098] The economic torque is determined based on the driving force.

[0099] In some embodiments of the present invention, the expression for the economic torque is as follows:

[0100] Where T represents economic torque, F t η1 represents the driving force, r represents the wheel radius, η2 represents the gear ratio, η3 represents the final drive ratio, and η3 represents the transmission efficiency.

[0101] Once the acceleration is determined, the acceleration resistance can be calculated by multiplying the acceleration by the vehicle's mass.

[0102] When a wheel rolls, the elastic tire deforms on a hard surface, and internal friction causes elastic hysteresis loss, thus forming rolling resistance. The formula for calculating the rolling resistance Ff of a vehicle is: Ff = vehicle mass * g * vehicle resistance coefficient.

[0103] The component of the air force acting on a car when it is traveling in a straight line is called air resistance. It is proportional to the dynamic pressure of the relative velocity of the airflow. The specific formula for calculating air resistance Fw is: Fw = air resistance coefficient * air density * frontal area * square of relative velocity with air / 2.

[0104] Gradient resistance is the loss of a car's weight along a slope when driving uphill. Because Chinese highway regulations stipulate that even in mountainous and hilly areas the maximum longitudinal slope cannot exceed 6%, the gradient of most roads is relatively small. Therefore, the sine of the gradient angle is approximately equal to the tangent, which is the slope value. The specific formula for calculating gradient resistance Fi is: Fi = vehicle mass * g * gradient.

[0105] According to the vehicle dynamics equation, the driving force equals the sum of rolling resistance, air resistance, and gradient resistance minus acceleration resistance. That is, the formula for calculating the driving force Ft is as follows: Ft=Ff+Fw+Fi–(vehicle mass*acceleration).

[0106] Therefore, the calculation method for economic torque T is: T = Ft * wheel radius / (gear ratio * final reducer ratio * transmission efficiency).

[0107] The expression for the economic torque T is as follows:

[0108] Where T represents economic torque, F t η1 represents the driving force, r represents the wheel radius, η2 represents the gear ratio, η3 represents the final drive ratio, and η3 represents the transmission efficiency.

[0109] Since the actual situation is generally more complex than theoretical calculations, a 5% increase in torque can be used as backup power.

[0110] The method for determining economic torque in a high-speed road slope scenario provided in this invention combines information such as the vehicle's current speed, target speed, slope and length of the road ahead in the high-speed road slope scenario, obtains the corresponding deceleration through a simulation model, and finally calculates the final economic torque based on the vehicle dynamics equation, thereby improving the fuel-saving rate.

[0111] Figure 4 is a second flowchart of an embodiment of the method for determining economic torque in a highway slope scenario provided by the present invention. As shown in Figure 4, the method for determining economic torque in a highway slope scenario includes:

[0112] S401, Ramp Segment Classification.

[0113] Based on the road map information provided by Tbox, the slope node data is initialized and classified to determine the slope type. Then, the slope nodes are traversed, and sliced ​​and initially merged according to the differences in slope type.

[0114] According to my country's highway route design specifications, the maximum longitudinal slope for expressways in plains and hilly areas is 3%, and for mountainous and hilly areas it is 5%; the maximum slope for first-class highways in plains and hilly areas is 4%, and for mountainous and hilly areas it is 6%. Therefore, it can be concluded that the slope of general roads will not exceed 6%. Thus, the following classification method is adopted:

[0115] (1) Invalid ramp type (default value, used for validity checks)

[0116] (2) 0% <= slope < 0.2%: flat road;

[0117] (3) 0.2% <= slope < 1%: uphill, slope is considered to be 1%;

[0118] (4) 1% <= slope < 2%: uphill, slope is considered to be 2%;

[0119] (5) 2% <= slope < 3%: uphill, slope is considered to be 3%;

[0120] (6) 3% <= slope < 4%: uphill, slope is considered to be 4%;

[0121] (7) 4% <= slope < 5%: uphill, slope is considered to be 5%;

[0122] (8) 5% <= slope < 6%: uphill, slope is considered to be 6%;

[0123] (9) Slope < 0%: Uphill, slope is considered 5%;

[0124] S402, ramp slice merging.

[0125] Based on the slope of the road ahead, the information of the next slope is obtained according to the road type of the slice. Then, starting from the slice, the end point of the slope is found. Finally, the entire slice is merged into a complete slope for subsequent processing.

[0126] S402.1 Find the starting slice of the first ramp ahead.

[0127] The upper layer initializes and categorizes the slope node data based on the road map information provided by tbox, slices the slopes according to their similarities and differences, and performs preliminary fusion before outputting the results to this layer. It then iterates through the slope slices of the road ahead, identifying the road type of each slice: if it is an invalid type, it returns an error and outputs an error message to the console; if it is a flat road or downhill type, it skips the step and continues to the next slice; if it is an uphill type, it records the current slice number as the starting slice number and proceeds to S402.2.

[0128] S402.2, Find the end slice of the first ramp ahead.

[0129] Starting from the initial slice number recorded in step S402.1, the process iterates backwards. If the current slice type is neither downhill nor flat, the current slope length is added to the merged slice, and the ending slice number is updated to the current slice number. If the current slice type is both flat and downhill, the traversal ends. This process yields one or more consecutive road slices, which are treated as a complete uphill slope, and the initial slice number, ending slice number, and total slope length of this uphill slope are known.

[0130] S403, Extracting information from the first ramp. Calculate the ramp gradient and the distance from the first ramp.

[0131] If the initial slice number is zero and equal to the ending slice number, meaning the current ramp consists of a single slice and is the first segment, it indicates that the vehicle is going uphill. In this case, the slope of the ramp is the slope of the current slice.

[0132] If the initial slice number is zero and the initial slice number is not equal to the end slice number, meaning the current ramp consists of multiple slices and starts from the first segment, it indicates that the vehicle is going uphill. At this time, the slope of the ramp is the weighted average slope of all slices (calculated and accumulated for each slice in the ramp: slope of a single slice * slope length of a single slice / total length of the ramp).

[0133] If the initial slice number is not zero and the initial slice number is equal to the end slice number, meaning the current ramp consists of a single slice and is not the first segment, it indicates that the ramp is in front of the vehicle. In this case, the slope of the ramp is the slope of the current slice, and the distance from the ramp is the sum of the lengths of all slices before the initial slice.

[0134] If the initial slice number is not zero and is not equal to the ending slice number, meaning the current ramp consists of multiple slices and does not start from the first segment, it indicates that the ramp is in front of the vehicle. In this case, the slope of the ramp is the weighted average slope of all slices (calculated and accumulated for each slice within the ramp: slope of a single slice * slope length of a single slice / total length of the ramp), and the distance from the ramp is the sum of the lengths of all slices before the initial slice.

[0135] S404, Calculate economic acceleration.

[0136] S404.1 Construct a simulation model to simulate the target vehicle driving under various operating conditions. The simulation model consists of two parts.

[0137] Based on the obtained fusion slope information, combined with the simulation model (using Trucksim and MATLAB co-simulation, using Trucksim to build the controlled object model of the heavy truck, and using SimLink to build the cruise controller model, which can better simulate uphill and downhill conditions), the corresponding vehicle deceleration is determined.

[0138] S404.2, Speed ​​confirmation at the bottom and top of the slope.

[0139] The selection of the bottom speed is based on the recommended speed in the regulations, and also takes into account the speed range that allows the vehicle's engine to operate in the economic speed range under the current operating conditions. The final economic cruising speed is then used as the bottom speed.

[0140] The speed at the crest of a hill needs to be discussed on a case-by-case basis. If no gear shifting is required, the speed at the crest of a hill should be set to the lowest speed the vehicle can maintain without shifting, i.e., the lowest speed the vehicle can achieve in the current gear. If the vehicle must downshift, the speed at the crest of a hill should be set to the speed at the shift point corresponding to the final gear.

[0141] S404.3 Acceleration Confirmation.

[0142] Once the economical velocities at the bottom and top of the slope are determined, the corresponding acceleration values ​​can be calculated using the model by combining the slope length and gradient data obtained from S403. However, in practical applications, calling the model for calculation every time is obviously impractical. The solution provided by this method is as follows:

[0143] S404.3.1. Create a table of discrete data, dividing the slope into 6 segments {1,2,3,4,5,6} and the slope length into 15 segments {200,400,600,800,1000,1200,1400,1600,1800,2000,2200,2400,2600,2800,3000}. Use the model to obtain the values ​​for the corresponding 6*15 cases and create a deceleration table.

[0144] S404.3.2 Select the appropriate gear for the slope length. Since the actual slope length is often not exactly equal to the designated lengths, it's necessary to select the appropriate gear based on the actual slope length. The strategy is to choose the smallest possible deceleration value to avoid excessive vehicle deceleration. If the slope length is less than 200, select gear 200; if the slope length is greater than 3000, select gear 3000; if it falls between two gears, choose the smaller one.

[0145] S404.3.3 Select the appropriate slope setting. Similar to slope length, slope is often not exactly an integer value, so it also needs to be handled. If the slope is greater than 0 and less than 1, select the slope setting of 1, and multiply the corresponding deceleration by the slope value, and then multiply by a scaling factor to ensure a smooth transition for small slopes; if the slope is greater than 6%, select the setting of 6; if the slope value is between the two settings, select the smaller setting.

[0146] S404.3.4. Look up the corresponding acceleration value in the table.

[0147] S405, Calculate the economic torque.

[0148] By calculating the vehicle's rolling resistance, air resistance, and slope resistance using the vehicle dynamics equations, the driving force of the vehicle can be obtained, thus determining the optimal economic torque for the slope.

[0149] S405.1 Calculate vehicle resistance.

[0150] S405.1.1 Calculate the rolling resistance of a vehicle. When the wheels roll, the elastic tire deforms on a hard surface, and internal friction causes elastic hysteresis loss, thus forming rolling resistance. The specific calculation formula is: Ff = vehicle mass * g * vehicle resistance coefficient.

[0151] S405.1.2 Calculate the air resistance of a vehicle. The component of the air force acting on a car in the direction of travel when the car is traveling in a straight line is called air resistance, which is directly proportional to the dynamic pressure relative to the airflow velocity. The specific calculation formula is: Fw = air resistance coefficient * air density * frontal area * square of relative velocity with air / 2.

[0152] S405.1.3 Calculate the vehicle's gradient resistance. Gradient resistance is the separation of a vehicle's weight along a slope when driving uphill. Due to regulations in my country that limit the maximum longitudinal slope even in mountainous areas to 6%, the gradients of most roads are relatively small. Therefore, the sine of the gradient angle is approximately equal to the tangent, which is the gradient value. The specific calculation formula is: Fi = Vehicle mass * g * Gradient.

[0153] S405.2 Calculate the economic torque.

[0154] S405.2.1 According to the vehicle dynamics equation, the driving force is equal to the sum of rolling resistance, air resistance, and gradient resistance, minus acceleration resistance, that is: Ft=Ff+Fw+Fi–(vehicle mass*acceleration).

[0155] S405.2.2 Calculate torque: T = Ft * wheel radius / (gear ratio * final reducer ratio * transmission efficiency).

[0156] S405.2.3 Since the actual situation is generally more complex than the theoretical calculation, the torque can be increased by 5% as a backup power.

[0157] The autonomous vehicle categorizes the received ramp slices, merges them according to their type, and extracts the information for the first ramp. Then, combined with a simulation model, it calculates the economic deceleration, and finally, based on the vehicle dynamics equations, calculates the economic torque and outputs it to the control layer.

[0158] The method for determining economic torque provided by this invention has the following advantages:

[0159] (1) The information provided by Tbox is used for the economic torque planning of the slope, which can obtain road information 3km ahead and make the planning more comprehensive;

[0160] (2) The simulation model built using heavy truck vehicle information can better simulate the dynamic characteristics of the research object;

[0161] (3) A ramp fusion method based on ramp slices was designed, which can correctly identify complete ramps and perform smoothing processing, which is convenient for calculation;

[0162] (4) A method for determining uphill deceleration was designed. The deceleration data calculated by the simulation model was simplified into a table. The corresponding economic deceleration can be obtained by querying the table in a specified way.

[0163] To better implement the economic torque determination method for highway slope scenarios in this embodiment of the invention, based on the economic torque determination method for highway slope scenarios, this embodiment of the invention also provides an economic torque determination device for highway slope scenarios. Figure 5 is a structural schematic diagram of an embodiment of the economic torque determination device for highway slope scenarios provided by this invention. As shown in Figure 5, the economic torque determination device 500 for highway slope scenarios includes:

[0164] The merging module 510 is used to merge the ramp slices based on the road type corresponding to the ramp slices, and determine the merged fused ramp; the ramp slices are obtained by slicing the road in front of the vehicle.

[0165] The first determining module 520 is used to determine the vehicle's acceleration based on the slope and length of the fusion ramp;

[0166] The second determining module 530 is used to determine the economic torque based on the acceleration.

[0167] The economic torque determination device 500 for highway slope scenarios provided in the above embodiments can realize the technical solutions described in the embodiments of the economic torque determination method for highway slope scenarios. The specific implementation principles of each module or unit can be found in the corresponding content of the embodiments of the economic torque determination method for highway slope scenarios, which will not be repeated here.

[0168] As shown in Figure 6, the present invention also provides an electronic device 600. The electronic device 600 includes a processor 601, a memory 602, and a display 603. Figure 6 only shows some components of the electronic device 600; however, it should be understood that it is not required to implement all the components shown, and more or fewer components may be implemented alternatively.

[0169] In some embodiments, processor 601 may be a central processing unit (CPU), microprocessor, or other data processing chip, used to run program code stored in memory 602 or process data, such as the method for determining economic torque in a highway ramp scenario in this invention.

[0170] In some embodiments, processor 601 may be a single server or a group of servers. The server group may be centralized or distributed. In some embodiments, processor 601 may be local or remote. In some embodiments, processor 601 may be implemented on a cloud platform. In some embodiments, the cloud platform may include a private cloud, public cloud, hybrid cloud, community cloud, distributed cloud, internal cloud, multi-cloud, or any combination thereof.

[0171] In some embodiments, memory 602 may be an internal storage unit of electronic device 600, such as a hard disk or memory of electronic device 600. In other embodiments, memory 602 may also be an external storage device of electronic device 600, such as a plug-in hard disk, smart media card (SMC), secure digital (SD) card, flash card, etc. equipped on electronic device 600.

[0172] Furthermore, the memory 602 may include both internal storage units of the electronic device 600 and external storage devices. The memory 602 is used to store application software and various types of data installed on the electronic device 600.

[0173] In some embodiments, display 603 may be an LED display, a liquid crystal display, a touch-sensitive liquid crystal display, or an organic light-emitting diode (OLED) touchscreen. Display 603 is used to display information from electronic device 600 and to display a visual user interface. Components 601-603 of electronic device 600 communicate with each other via a system bus.

[0174] In one embodiment, when processor 601 executes the economic torque determination program for a high-speed road ramp scenario stored in memory 602, the following steps can be implemented:

[0175] The ramp slices are merged based on the road type corresponding to the ramp slices to determine the merged ramp; the ramp slices are obtained by slicing the road in front of the vehicle.

[0176] The vehicle's acceleration is determined based on the slope and length of the fusion ramp.

[0177] Based on the acceleration, the economic torque is determined.

[0178] It should be understood that when the processor 601 executes the economic torque determination program for the high-speed road ramp scenario in the memory 602, in addition to the functions mentioned above, it can also perform other functions, as detailed in the description of the corresponding method embodiments above.

[0179] Furthermore, this embodiment of the invention does not specifically limit the type of electronic device 600 mentioned. Electronic device 600 can be a mobile phone, tablet computer, personal digital assistant (PDA), wearable device, laptop computer, or other portable electronic device. Exemplary embodiments of portable electronic devices include, but are not limited to, portable electronic devices running iOS, Android, Microsoft, or other operating systems. The aforementioned portable electronic device can also be other portable electronic devices, such as a laptop computer with a touch-sensitive surface (e.g., a touch panel). It should also be understood that in some other embodiments of the invention, electronic device 600 may not be a portable electronic device, but rather a desktop computer with a touch-sensitive surface (e.g., a touch panel).

[0180] Accordingly, embodiments of the present invention also provide a computer-readable storage medium for storing a computer-readable program or instruction. When the program or instruction is executed by a processor, it can implement the steps or functions of the method for determining economic torque in a high-speed road slope scenario provided in the above-described method embodiments.

[0181] On the other hand, the present invention also provides a computer program product, which includes a computer program that can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer is able to perform the steps or functions of the economic torque determination method in the high-speed road slope scenario provided in the above-described method embodiments.

[0182] Those skilled in the art will understand that all or part of the processes of the methods described in the above embodiments can be implemented by a computer program instructing related hardware (such as a processor, controller, etc.), and the computer program can be stored in a computer-readable storage medium. The computer-readable storage medium may be a disk, optical disk, read-only memory, or random access memory, etc.

[0183] The above provides a detailed description of the method, device, and medium for determining economic torque in a high-speed road slope scenario provided by the present invention. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. An economic torque determination method in a highway ramp scenario, characterized by, The method comprises the following steps: Merging the ramp slices based on the road types corresponding to the ramp slices to determine a merged fusion ramp; The ramp slices are obtained by slicing the road in front of the vehicle; Determining the acceleration of the vehicle based on the slope and slope length of the fusion ramp; Determining the economic torque based on the acceleration.

2. The method of claim 1, wherein, The method comprises the following steps: Traversing the ramp slices, and determining the sequence number of the current ramp slice as a starting sequence number when it is determined that the road type of the current ramp slice is an uphill type; Traversing the ramp slices based on the starting sequence number, merging the next ramp slice with the current ramp slice when it is determined that the road type of the next ramp slice is an uphill type, and determining the sequence number of the next ramp slice as an ending sequence number; Stopping the traversal and obtaining the merged fusion ramp when it is determined that the road type of the next ramp slice is a downhill type or a flat road type.

3. The method of claim 2, wherein, Before the step of determining the acceleration of the vehicle based on the slope and slope length of the fusion ramp, the method further comprises the following steps: Determining the slope and slope length of the fusion ramp based on the starting sequence number and the ending sequence number.

4. The method of claim 3, wherein, The step of determining the acceleration of the vehicle based on the slope and slope length of the fusion ramp comprises the following steps: Segmenting a preset slope to obtain a plurality of slope values; Segmenting a preset slope length to obtain a plurality of slope length values; Corresponding each slope value with a different slope length value to determine a corresponding acceleration value through a simulation model; the simulation model is a vehicle dynamics model constructed based on trucksim and matlab; Constructing an acceleration table based on the corresponding relationship among the slope values, the slope length values and the acceleration values; Determining the acceleration of the vehicle in the acceleration table based on the slope and slope length of the fusion ramp.

5. The method of claim 4, wherein, The step of determining the economic torque based on the acceleration comprises the following steps: Determining an acceleration resistance based on the acceleration; Determining a driving force based on the rolling resistance, the air resistance, the slope resistance and the acceleration resistance of the vehicle; Determining the economic torque based on the driving force.

6. The method of claim 5, wherein, The expression of the economic torque is as follows: where T represents the economic torque, F t represents the driving force, r represents the wheel radius, η1 represents the gear transmission ratio, η2 represents the main reducer transmission ratio, and η3 represents the transmission efficiency.

7. An economic torque determination device in a highway ramp scenario, characterized by, The method comprises the following steps: A merging module is configured to merge the ramp slices based on the road types corresponding to the ramp slices to determine a merged fusion ramp; The ramp slices are obtained by slicing the road in front of the vehicle; A first determining module is configured to determine the acceleration of the vehicle based on the slope and slope length of the fusion ramp; A second determining module is configured to determine the economic torque based on the acceleration.

8. An electronic device, comprising: The computer program is executed by the processor to implement the method for determining the economic torque in the high-speed road ramp scenario. The computer program is executed by the processor to implement the method for determining the economic torque in the high-speed road ramp scenario. The computer program is executed by the processor to implement the method for determining the economic torque in the high-speed road ramp scenario.

9. A computer readable storage medium having stored thereon a computer program, characterized in that, ​ 10. A computer program product comprising a computer program, characterized in that, ​

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